Дисертації: "Ultrasounds assisted extraction"

1

Belghith, Yosra. "Eco-extraction de biomolécules à haute valeur ajoutée à partir de grignons d’olive." Electronic Thesis or Diss., Avignon, 2023. http://www.theses.fr/2023AVIG0119.

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Анотація:

Le grignon d’olive est le coproduit principal généré par le procédé d’extraction de l’huile d’olive. Bien que délétère pour l’environnement, le grignon d’olive est une source potentielle de molécules naturelles bénéfiques pour la santé humaine. Une partie de nos travaux a été consacrée à la caractérisation d’un extrait éthanolique de grignon d’olive. L’analyse par UPLC/MS nous a permis d’identifier 59 métabolites secondaires dont les plus abondants sont l’hydroxytyrosol, le tyrosol, l’oleuropéine aglycone, l’oléoside, l’acide caféique et l’acide pcoumarique. Des tests biologiques ont montré que l’extrait éthanolique était doté d’activité antioxydante, antidiabétique et analgésique. Une deuxième partie s’est focalisée sur l’optimisation des rendements d’extraction des polyphénols du grignon d’olive à l’aide de technologies d’extraction éco-responsables. Ces travaux nous ont amené à conclure que les conditions optimales d’extraction ont été obtenues pour un ratio de (60/40) (EtOH/H2O) à l’aide du procédé d’extraction accélérée par solvant. Dans une dernière partie, une nouvelle approche a été développée visant l’optimisation de l’extraction des composés phénoliques en considérant des huiles végétales comme solvant d’extraction. Basé sur un plan factoriel complet à trois facteurs (type d’huile, température et technique d’extraction), nous avons pu montrer que les conditions optimales de l’extraction des polyphénols du grignon étaient l’extraction assistée par ultrasons dans l’huile d’olive à 65°C
Olive pomace is the main by-product generated through olive oil extraction. Although toxic to the environment, olive pomace is an important source of natural products beneficial to human health. Part of our work focuses on an ethanolic extract of pomace. UPLC/MSanalyses allowed us to identify 59 secondary metabolites, the most abundant of which are hydroxytyrosol, tyrosol, oleuropein aglycone, oléoside, caffeic acid and p-coumaric acid. In addition, biological tests have shown that the ethanolic extract has antioxidant, anti-diabetic and analgesic activities. A second part based on the optimization of polyphenol extraction yields from olive pomace was carried out. This work led us to conclude that 60:40 EtOH: H2O was the best extraction solvent ratio and that “accelerated solvent extraction” was the best extraction process. In the last part, a new approach was developed to optimize the extraction of phenolic compounds using vegetable oils as extraction solvent. Based on a complete factorial design with three factors (type of oil, temperature and extraction technique), we have concluded that the optimal conditions for the extraction of polyphenols from pomace are as follows: extraction with olive oil at 65°C using ultrasound-assisted extraction

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2

Duhayon, Christophe. "Copper solvent extraction by ultrasound-assisted emulsification." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210155.

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The goal of this research is to improve an extractive metallurgy process based

on solvent extraction. This process should fit the exploitation of small local

copper-rich deposits. In these conditions, the plant has to be as compact as

possible in order to be easily transported from one location to a subsequent

one. Improved extraction kinetics could ensure a high throughput of the

plant despite its compactness. In addition, the extraction reagent should

not be damaging for the environnement. On this basis, we propose to use

ultrasound-assisted solvent extraction. The main idea is to increase the

extraction kinetics by forming an emulsion in place of a dispersion thanks to

the intense cavitation produced by ultrasound. The benefit of this method

is to improve the copper extraction kinetics by increasing the interfacial

surface area and decreasing the width of the diffusion layer. We studied the

implementation of an highly branched decanoic acid (known as Versatic-

10®acid) as a copper extraction reagent dispersed in kerosene.

Emulsification is monitored through the Sauter diameter of the organic

phase droplets in aqueous phase. This diameter is measured during pulsed

and continuous ultrasound irradiation via a static light scattering technique.

The phenomenon of emulsification of our system by ultrasound is effective,

and the emulsification process carried out in the pulsed ultrasound mode is

at least as efficient as the emulsification obtained under continuous mode.

No improvement of emulsification is observed beyond a threshold time of

the ultrasound impulse. This may be attributed to a competition between

disruption and coalescence. The use of mechanical stirring combined with

pulsed ultrasound allows to control the droplet size distribution.

In presence of ultrasound, the extraction kinetics of Versatic-10 acid is

multiplied by a factor ten, and therefore reached a value similar to the kinetics

observed without ultrasound with an industrial extractant such as

LIX-860I®(Cognis). Extraction kinetics measurements are carried out by

monitoring the copper ion concentration in the aqueous phase with an electrochemical

cell.

We conclude that ultrasound-assisted emulsification can be implemented

under certain conditions. Emulsification is a first step, and the following

destabilization step has to be studied. The device using ultrasound-assisted

emulsification should be followed by an efficient settling-coalescing device. A

possible solution would be to promote emulsion destabilization by increasing

the ionic strength with an addition of MgSO4, a salt that is not extracted

by the extraction reagent in the considered range of pH.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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3

Ozcan, Evren. "Ultrasound Assisted Extraction Of Phenolics From Grape Pomace." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12606908/index.pdf.

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Grape pomace is a by-product of wineries. It is one of the most potent antioxidant sources due to its high phenolic content. In this thesis study, ultrasound assisted extraction of phenolic compounds from Merlot grape pomace has been studied. The effects of sonication time, subsequent extraction time in shaking water bath at 45°
C and composition of the solvent on extraction efficiency and recovery of phenolics were studied by response surface methodology. Folin-Ciocalteu colorimetric method was used to analyze effects of process parameters on the total phenolic content of the extracts. The best recovery (47.2 mg gallic acid equivalents of total phenolics per g of dried grape pomace) was obtained using 30 % aqueous ethanol and applying 6 minutes of sonication followed by 12 minutes of shaking in water bath at 45°
C.

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4

Melikoglu, Mehmet. "Ultrasound Assisted Extraction Of Lipids And Antioxidants From Wheat Germ." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12605799/index.pdf.

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The aim of this thesis work was to extract lipids and antioxidants from wheat germ using an ultrasonic bath. Alternative solvents: Ethanol, isopropanol and acetone were used for the extraction purposes and for the fat content determination hexane was used. Alternative solvents dissolve wax, phospholipids and some other proteins because of their polar nature which increased the yield. Since waxes and some proteins can be added to the soaps and creams which were made from carrier oils, obtaining these substances together with the oil in the extract was very useful. For isopropanol a linear relation was found between the extract ratio and ultrasonication time. The highest extract ratios were achieved with ethanol. For 30 minutes of ultrasonication 0.10 g extract / g germ was obtained. After the extraction in order to enhance the phase separation between the solid phase (germ and other solids) and the extract phase, combinations of centrifugation, storage in the refrigerator and decantation were tested. The technique involving storage the extracts in the refrigerator for 24 hours and centrifugation at 2800 rpm for 20 minutes gave the second highest yield but the best phase separation. Ethanol extracts from both roasted and nonroasted wheat germs were characterized in terms of their total polyphenol contents. For non roasted wheat germs total polyphenol contents of 200 mg gallic acid / L solution and for roasted wheat germs an average of 170 mg gallic acid / L solution were obtained for 30 minutes of ultrasonic extraction. For nonroasted wheat germs weak but significant linear relations were found between total polyphenol contents of the extracts and ultrasonication time.

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5

Latheef, Mohsin Bin. "Pulsed ultrasound-assisted solvent extraction of oil from soybeans and microalgae." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107890.

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The two biological oils used in this study come from two distinctly different sources; soybeans and microalgae. Yet, both are economically important due to the similarities in their nutritional and industrial value. Besides being the top sources for health-promoting polyunsaturated fatty acids (PUFA), both oils are becoming increasingly important in the production of biodiesel (through transesterification). The microalgal species chosen for the current study was Nannochloropsis oculata, a small marine microalga known for its unusually high lipid content. Conventionally, soybean and microalgal oils are extracted using the organic solvents n-hexane and chloroform-methanol (CM), respectively. However, both solvents have several drawback associated with them; n-hexane is highly volatile and flammable, while CM poses high toxicity and safety concerns (due to the presence of chloroform). The alternative solvent mixture of hexane-isopropanol (HIP), as a result of its better safety and efficiency qualities, has been used as the primary solvent in this study. Ultrasound-assisted solvent extraction or UASE has recently become popular as a novel alternative to traditional standalone solvent extraction, offering numerous advantages such as shorter treatment times, simpler sample preparation and higher efficiency. Hence, pulsed UASE with HIP (3:2 v/v) as solvent was the principal technique investigated in this study. Ultrasonic processing was carried out using an immersed probe (or sonotorode) resonating at a maximum amplitude of 124 µm. Two parameters related to UASE were studied; resonance amplitude and effective treatment time. The oil yields (assessed gravimetrically) and fatty acid profiles (from GC) of the extracted oils were analysed. The study showed that pulsed UASE resulted in high extraction efficiency (upto 19.92% oil yield was obtained for soybeans and upto 69.53% oil was extracted from N. oculata). Both amplitude and treatment time were found to have significant effects on oil yield. However, the study also showed that high resonance amplitude and treatment time did not necessarily produce high yields. For soybeans, the oil extracted by pulsed UASE was found to be comparable in fatty acid composition to that extracted by traditional methods such as Soxhlet and room temperature shaking. In contrast, the extracted microalgal oil had a superior PUFA profile compared to these two traditional methods.
Dans cette étude, deux huiles de sources très différentes sont utilisées; les graines de soja et les microalgues. Chacune de ces huiles possèdent un intérêt économique important en raison de sa valeur nutritive et industrielle. Elles sont connues pour être une des principales sources en acides gras polyinsaturés (AGPI), et deviennent de plus en plus utilisées dans la production de biodiesel (par transestérification). L'espèce de microalgues choisie pour l'étude était Nannochloropsis oculata, une petite microalgue marine connue pour sa teneur en lipides anormalement élevés. Traditionnellement, les huiles de soja et de microalgues sont extraites en utilisant respectivement, les solvants n-hexane et le chloroforme-méthanol (CM). Toutefois, ces deux solvants ont plusieurs inconvénients; le n-hexane est très volatil et inflammable, tandis que le CM possède une toxicité élevée et des problèmes de sécurité (en raison de la présence de chloroforme). Un solvant alternatif, l'hexane-isopropanol (HIP), a donc été utilisé comme solvant principal dans cette étude en raison de sa moins grande nocivité et de son efficacité. L'extraction assistée par ultrason avec solvant ou EAUS est de plus en plus utilisée comme nouvelle alternative à l'extraction par solvant traditionnelle, offrant de nombreux avantages tels qu'un temps de traitement plus court, une préparation de l'échantillon plus simple et une meilleure efficacité. Ainsi, la principale technique utilisée dans cette étude a été la technique EAUS avec HIP (3:2 v/v) comme solvant. Le traitement par ultrasons a été réalisée en utilisant une sonde immergée (ou sonotorode) résonnant à une amplitude maximale de 124 µm. Deux paramètres ont été étudiés; l'amplitude de résonance et la durée de traitement. Les rendements en huile (évaluée par gravimétrie) et la composition en acides gras (par CG) des huiles extraites ont été analysées. L'étude a montré que l'EAUS abouti à des taux d'extraction élevés (jusqu'à 19.92% de rendement en huile pour les graines de soja et jusqu'à 69.53% d'huile extraite à partir de N. oculata). L'amplitude et la durée de traitement ont tous deux des effets significatifs sur le rendement en huile. Cependant, l'étude a également montré qu'une amplitude de résonance et un temps de traitement élevé ne donnent pas nécessairement un fort rendement. Pour les graines de soja, la composition en acide gras de l'huile extraite par EAUS est comparable à celle extraite par des méthodes traditionnelles telles que Soxhlet et l'extraction par agitation à température ambiante. En revanche, l'huile extraite des microalgues a une teneur en AGPI plus élevé par rapport à ces deux méthodes traditionnelles.

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6

Yu, Dajun. "Ultrasound-assisted enzymatic extraction of protein hydrolysates from brewer's spent grain." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/97875.

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Brewer's spent grain (BSG) is the most abundant by-product of the brewing industry and its main application is limited to low-value cattle feed. Since BSG contains 20 to 25% of proteins, it has the potential to provide a new protein source to the food industry. In this research, an ultrasound-assisted enzymatic extraction was designed to extract protein hydrolysates from BSG. Original BSG and ultrasound pretreated BSG were hydrolyzed under different enzyme (Alcalase) loadings and incubation times. Centrifugation was applied to separate solubilized proteins from insoluble BSG residue. When the enzyme loading increased from 1 to 40 uL /g BSG, the solubilized proteins increased from 34% to 64.8%. The application of ultrasound further increased the solubilized proteins from 64.8% to 69.8%. Solubilized proteins from ultrasound pretreated BSG was significantly higher (p < 0.05) than that from the original BSG. Particle size distribution analysis showed that the application of ultrasound pretreatment reduced the BSG particle size from 331.2 to 215.7 um. Scanning electron microscopy images revealed that the BSG particle surface was partially ruptured by the ultrasound pretreatment. These two phenomena might have contributed to the increased protein separation efficiency with ultrasound pretreatment. The solubility (pH 1.0 to 11.0) of protein hydrolysate increased by the application of ultrasound and the ultrasound did not lead to the change of the amino acid composition of the separated protein hydrolysates. Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile, the protein was degraded to peptides which had molecular weights lower than 15 kDa. The color of the separated protein hydrolysates by enzymatic hydrolysis was brighter and lighter than the original BSG. The application of ultrasound did not affect the color of the separated protein hydrolysates. Overall, the ultrasound pretreatment prior to enzymatic hydrolysis enhanced the extraction of proteins from BSG in terms of higher protein separation efficiency, lower enzyme loadings, and reduced incubation time. This study developed a novel and green method to effectively extract value-added protein hydrolysates from the low-value food processing byproducts.
MSLFS

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7

Gelmez, Nilufer. "Ultrasound Assisted And Supercritical Carbon Dioxide Extraction Of Antioxidants From Roasted Wheat Germ." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609364/index.pdf.

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This study covers the extraction of antioxidants from wheat germ
which is the byproduct of the flour-milling industry and a rich source of antioxidants
with Ultrasound Assisted (UAE) and Supercritical Carbon Dioxide (SC-CO2) extractions. Extraction conditions were ultrasonication time (1&ndash
11 min), temperature (20&ndash
60°
C) and ethanol level (5&ndash
95%) for UAE, and pressure (148&ndash
602 bar), temperature (40&ndash
60°
C) and time (10&ndash
60 min) for SC-CO2 extraction. The extraction conditions were optimized based on yield (%), total phenolic contents (TPC, mg GAE/g extract) and antioxidant activities (AA, mg scavenged DPPH&
#729
/g extract) of the extracts, using Central Composite Rotatable Design. Total tocopherol contents (TTC) of the extracts were determined, as well. UAE (at 60°
C) with low ethanol level (~5-30%) and short times (1-3 min) provided protein rich extracts with high yield, medium TPC and AA. On the other hand, with high ethanol level (~90%) and long times (6-11 min), waxy structured extracts with low yield but high TPC and AA were obtained. SC-CO2 extraction at 442 bar, 40º
C and 48 min. enabled almost 100% recovery of wheat germ oil (9% yield) but TPC and AA of the extracts were low. On the contrary, the extracts obtained at lower pressures (~150bar) and shorter times (~10 min) at 50-60º
C had high TPC and AA since the oil yield was low. However, TPC and AA of these extracts were only half of those extracted by UAE. Maximum tocopherol (7.142 mg tocopherol/g extract) extraction was achieved at 240 bar, 56º
C for 20 min. Both of the methods extracted high amounts of tocopherols from roasted wheat germ (SC-CO2 extraction
0.31 mg tocopherol/g germ, UAE
0.33 mg tocopherol/g germ) but TTC of the extracts obtained by SC-CO2 extraction was superior compared to 1.170 mg tocopherol/g extract obtained by UAE at 9 min, 58º
C and 95% ethanol level. All these extracts with different characteristics have potential uses in cosmetic and food industry depending on the targeted specific application.

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8

Markevicius, Gediminas. "Pressure Variation Assisted Fiber Extraction and Development of High Performance Natural Fiber Composites and Nanocomposites." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/117.

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It is believed, that due to the large surface areas provided by the nano scale materials, various composite properties could be enhanced when such particles are incorporated into a polymer matrix. There is also a trend of utilizing natural resources or reusing and recycling materials that are already available for the fabrication of the new composite materials. Cellulose is the most abundant natural polymer on the planet, and therefore it is not surprising to be of interest for composite fabrication. Basic structures of cellulose, comprised of long polysaccharide chains, are the building blocks of cellulose nano fibers. Nano fibers are further bound into micro fibrils and macro fibers. Theoretically pure cellulose nano fibers have tremendous strengths, and therefore are some of the most sought after nano particles. The fiber extraction however is a complex task. The ultrasound, which creates pressure variation in the medium, was employed to extract nano-size cellulose particles from microcrystalline cellulose (MCC). The length and the intensity of the cavitations were evaluated. Electron microscopy studies revealed that cellulose nanoparticles were successfully obtained from the MCC after ultrasound treatment of just 30 minutes. Structure of the fractionated cellulose was also analyzed with the help of X-ray diffraction, and its thermal properties were evaluated with the help of differential scanning calorimetry (DSC). Ultrasound treatment performed on the wheat straw, kenaf, and miscanthus particles altered fiber structure as a result of the cavitation. The micro fibers were generated from these materials after they were subjected to NaOH treatment followed by the ultrasound processing. The potential of larger than nano-sized natural fibers to be used for composite fabrication was also explored. The agricultural byproducts, such as wheat or rice straw, as well as other fast growing crops as miscanthus or kenaf, are comprised of three basic polymers. Just like in wood the polymers are: cellulose, hemicelluloses, and lignin. When subjected to elevated pressures and temperatures, we are able to get access to some of these natural polymers and use them as a matrix material for composite fabrication. Therefore, fabrication of composite materials without addition of synthetic polymers is possible. Thermal and mechanical properties of such composites are evaluated with the help of electron microscopy, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and flexural strength measurements. The chemical changes in the composites are also probed with the help of Fourier transform infrared (FTIR) analysis. Various additives introduced into composite materials provide different properties. The addition of small amounts of synthetic polymers further enhances the properties of natural fiber composites and do not require high fabrication pressures. Calcium sulfite crystals, which are one of the coal combustion products, were combined with the natural fibers and recycled HDPE polymer to form wood substitute composites. The introduction of these additives resulted in composites with the properties similar to those of the natural wood. Coal combustion products, often used in composite material fabrication, contain mercury which may be rereleased during composite fabrication. Mercury behavior under composite fabrication conditions, such as elevated pressures and temperatures were evaluated. Sulfite rich scrubber material, generated during the flue gas desulphurization process was the main target of the study. It was observed that the release of the mercury is highly dependent on the composite fabrication pressure as well as the temperature.

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Pacetta, Cosmo Fernando. "Estudo de diferentes metodologias para a obtenção de extratos de folhas de oliveira (Olea europaea) contendo oleuropeína." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-05052014-135759/.

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A oleuropeína é o mais abundante biofenol presente nas folhas de oliveira (Olea Europaea), com importantes funções antimicrobiana e antioxidante. Estudos visando à obtenção deste composto têm sido conduzidos, porém, muitos deles utilizam solventes tóxicos e métodos caros. A presente dissertação teve por objetivo estudar diferentes metodologias para a obtenção de extratos de folhas de oliva contendo quantidades significativas de oleuropeína. Os extratos foram obtidos a partir de folhas de oliva micronizadas, com ou sem pré-tratamento para redução do teor de clorofila, submetidas a contatos simples ou múltiplos com diferentes solventes, como dietil éter, clorofórmio, acetona, etanol, 1-propanol, 2-propanol, água e soluções hidroalcoólicas com diferentes concentrações. O contato das folhas micronizadas com os solventes foi promovido pelos seguintes métodos: agitação manual em temperatura ambiente, agitação mecânica a 50 ºC, ultrassom ou uma combinação desses dois últimos, totalizando 38 experimentos, sendo que em 17 destes os extratos foram produzidos na forma líquida e 21 na forma sólida. Os resultados mostraram que, de maneira geral, a etapa prévia de redução do teor da clorofila (realizada através de sucessivos contatos com hexano, diclorometano ou ainda, com CO2 supercrítico) não foi vantajosa, devido à elevada quantidade de solventes utilizados em relação às quantidades de extratos obtidos. Nestes experimentos, a maior concentração de oleuropeína, 1,88%, foi detectada no procedimento em que as folhas micronizadas foram previamente umedecidas com etanol e limpas com CO2 supercrítico, e posteriormente colocadas em contato com a mistura etanol e água, na proporção 1:1, utilizando o ultrassom combinado com a agitação mecânica como método de extração. Nos experimentos finais do trabalho, foi estudada ainda a adição de ácidos orgânicos (cítrico ou acético), juntamente com os solventes hidroalcoólicos (diferentes teores de água) no momento da extração da oleuropeína em banho de ultrassom, utilizando amostras que não foram previamente tratadas para remoção da clorofila. A combinação do ácido acético com a solução etanólica contendo 30 % de água resultou em um extrato com 2,17 % de oleuropeína, em apenas 1 contato com o solvente. Quando três contatos foram utilizados, nestas mesmas condições, o teor de oleuropeína aumentou para 4,8 %, maior do que alguns valores encontrados na literatura, utilizando o mesmo método de extração, indicando que processo ainda pode ser otimizado, utilizando técnicas simples e solventes que não agridam o meio ambiente.
Oleuropein is the most abundant biofenol present in olive leaves (Olea europaea), presenting important antioxidant and antimicrobial functions. Studies focusing on obtaining this compound have been conducted; however, many of them use toxic solvents and expensive methods. The present work aimed to study different methodologies for obtaining extracts from olive leaves containing significant amounts of oleuropein. The extracts were obtained from micronized olive leaves, with or without pretreatment for reducing the chlorophyll content, submitted to single and multiple contacts with different solvents such as diethyl ether, chloroform, acetone, ethanol, 1- propanol, 2 -propanol, water and hydroalcoholic solutions at different concentrations. The contact between the micronized leaves and the solvents was promoted by the following methods: manual shaking at room temperature, mechanical agitation at 50 °C, ultrasound or a combination of these last two methods, totaling 38 experiments, from which in 17 of them the extracts were produced in the liquid form, and in 21 in the solid form (as a powder). The results show that, in general, previous step of reducing the content of chlorophyll (performed by successive contacts with hexane, dichloromethane or with supercritical CO2) was not advantageous due to the high amount of solvent used in relation to amounts of extracts. In these experiments, the highest concentration of oleuropein, 1.88 % was detected in the procedure in which the micronized leaves were previously soaked with ethanol and cleaned with supercritical CO2 and then placed in contact with the mixture of ethanol and water in the proportion 1:1, using ultrasound combined with mechanical agitation as extraction method. In the last experiments of the work, the addition of organic acids (citric or acetic acid) together with hydroalcoholic solvents (different water contents) in the extraction of oleuropein in ultrasound was studied, using samples that have not previously been treated for removal of chlorophyll. The combination of acetic acid to the ethanolic solution containing 30 % of water resulted in an extract with 2.17 % of oleuropein, with only one contact to the solvent. When three contacts were used, under the same conditions, the oleuropein content increased to 4.8 %, larger than some values found in the literature, using the same extraction method, indicating that the process can be further optimized using simple techniques and solvents that do not harm the environment.

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10

Dary, Chhavarath. "Mise au point des espèces du genre Stephania au Cambodge : études systématique, phytochimique et pharmacologique." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5502/document.

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L’objectif de la thèse est une mise au point des espèces de Stephania répertoriées au Cambodge par l’étude systématique, phytochimique et pharmacologique. Du point de vue systématique, les travaux ont permis de répertorier sept espèces et deux variétés de Stephania au Cambodge : S. cambodica, S. japonica var. discolor et var. timoriensis, S. oblata, S. pierrei, S. rotunda (espèce-type), S. suberosa, et S. venosa. La clef de détermination établie lors de ce travail de thèse permet d’identifier ces espèces. D’après les résultats phylogénétiques, seul S. pierrei est monophylétique, ce qui représente moins de 10% des espèces de Stephania. L’étude chimique de cinq espèces a été réalisée par des méthodes chromatographiques (CLHP, UCLHP) et des méthodes spectroscopiques. Différents alcaloïdes ont été proposés comme marqueurs : la palmatine, la roémérine et la tétrahydropalmatine pour S. cambodica et S. rotunda, la cépharanthine, la tétrahydropalmatine et la xylopinine pour S. suberosa, la cépharanthine pour S. pierrei, la crébanine, et la tétrahydropalmatine pour S. venosa. Neuf alcaloïdes ont été isolés à partir du tubercule de S. cambodica, dont un nouveau composé dénommé «angkorwatine ». Une méthode d’éco-extraction des alcaloïdes assistée par ultrasons a été mise au point et optimisée par un plan d’expérience pour cette espèce. Une méthode analytique par UCLHP a été développée et validée pour le contrôle qualité de S. cambodica. Les résultats montrent que les extraits hydroéthanoliques obtenus par macération à partir du tubercule de S. suberosa, S. venosa et S. rotunda présentent une activité anti-inflammatoire importante (in vitro) avec un ratio anti-inflammatoire élevé
The thesis aims to provide update on species of the genus Stephania recorded in Cambodia by systematic, phytochemical and pharmacological studies.The systematic study allowed to list seven species and two varieties of Stephania in Cambodia: S. cambodica, S. japonica var. discolor and var. timoriensis, S. oblata, S. pierrei, S. rotunda (type species), S. suberosa and S. venosa. The presence of S. japonica var. timoriensis and S. oblata is reported for the first time in Cambodia. According to the phylogenetic results, only S. pierrei is monophyletic, which represents less than 10% of species in the genus Stephania. Chemical studies on the tubers of five species were carried out using chromatographic methods (HPLC, UHPLC) and spectroscopic methods. Different isolated alkaloids have been proposed as markers: palmatine, roemerine and tetrahydropalmatine for S. cambodica and S. rotunda, cepharanthine, tetrahydropalmatine, and xylopinine for S. suberosa, cepharanthine for S. pierrei, crebanine, and tetrahydropalmatine for S. venosa. Nine alkaloids belonging to five classes were isolated from the tuber of S. cambodica and a new compound namely "angkorwatine" was described. Ultrasound assisted extraction of alkaloids was developed and optimized by Design of Experiment for this species. This innovative extraction is a good alternative to conventional methods. An analytical UHPLC method was developed and validated for the quality control of S. cambodica. Results show that hydroethanolic extracts obtained by maceration of S. suberosa, S. rotunda and S. venosa exhibit significant anti-inflammatory activity with high anti-inflammatory ratio (selectivity index)

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Mendez, Lina Maria Rayo. "Isolamento de polissacarídeos não amiláceos da banana (musa cavendishii L. variedade Nanicão) e seu potencial uso como ingrediente funcional." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-03102018-101135/.

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Neste trabalho, polissacarídeos não amiláceos (PNAs) da banana madura com potencial de propriedades imunomoduladoras foram obtidos por meio da remoção dos açúcares solúveis (glicose, frutose e sacarose) do purê de banana submetido a duas técnicas de extração: sólido-líquido (ESL) com agitação mecânica e assistida por ultrassom (EAU) usando etanol a 99,5 g/100 g como solvente. Para o estudo em batelada, diferentes razões da matéria-prima/solvente (1:5, 1:7 e 1:10) g/mL, tempos de extração (30, 60 e 90) min e duas temperaturas de (25 e 65) °C foram estudados. No estudo cinético, o impacto da redução da razão matéria-prima/solvente de 1:5 para 1:3 g/mL foi estudado até 90 min, nas mesmas condições estudadas na extração em batelada. O teor de açúcares solúveis (AS) medido nos extratos foi superior na temperatura de 65°C, porém às razões de 1:7 e 1:10, não resultou em maior quantidade de AS nos extratos, portanto, menores quantidades de etanol podem ser usadas diminuindo custos. Com o emprego da técnica EAU à 25 °C e tempo de extração de 30 min, foi observado que uma redução da razão matéria-prima/solvente até 1:3 g/mL produz maior rendimento de processo. No entanto, foi observado que maiores tempos de extração promoveram degradação da parede celular da matéria-prima. Entre os modelos cinéticos testados, o ajuste do modelo de Patricelli aos dados experimentais indicou que a ESL é regida pela fase de lavagem em que ocorreu 85 % da extração dos AS. Frações molares de glicose, ácidos galacturônicos, manose, arabinose, xilose, galactose de conteúdo monossacarídeo foram observadas nos rafinados, indicando possivelmente serem parte de polissacarídeos do tipo ?-glicanos, xilomananos glucomananos, arabinogalactanos e arabinoxilanos.
In this work, non-starch polysaccharides (PNAs) of ripe bananas with potential for immunomodulatory properties were obtained by means removing the soluble sugars (glucose, fructose and sucrose) from banana puree submitted to two extraction techniques: solid-liquid (SLE) with mechanical stirring and ultrasonic assisted (UAE) using 99.5 g/ 100 g ethanol as solvent. For the batch study, different ratios of the raw material/ solvent (1:5, 1:7 and 1:10) g/ mL, extraction times of (30, 60 and 90) min and two temperatures of (25 and 65 ) °C were studied. In the kinetic study, the impact of reducing the raw material/ solvent ratio from 1:5 to 1:3 g/ mL was studied up to 90 min, under the same conditions studied in batch extraction. The soluble sugar content (AS) measured in the extracts was higher at temperature of 65 °C, however, at the ratios of 1:7 and 1:10, did not result in higher amount of AS in the extracts, therefore, smaller amounts of ethanol can be costs. With the use of the UAE technique at 25 °C and extraction time of 30 min, it was observed that a reduction of the raw material / solvent ratio up to 1:3 g / mL produces a higher process yield. However, it was observed that longer extraction times promoted degradation of the cell wall of the raw material. Among the kinetic models tested, the adjustment of Patricelli model to the experimental data indicated that the SLE the predominance is by the washing phase in which 85% of the AS extractions occurred. Glucose molar fractions, galacturonic acids, mannose, arabinose, xylose, galactose of monosaccharide content were observed in the raffinates, indicating possibly being part of polysaccharides as ?-glycan, xylomannans, glucomannans, arabinogalactans and arabinoxylans.

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Khan, Muhammad Kamran. "Polyphénols d’agrumes (flavanones) : extraction de glycosides de la peau d’orange, synthèse de métabolites chez l’homme (glucuronides) et étude physico-chimique de leur interaction avec la sérum albumine." Thesis, Avignon, 2010. http://www.theses.fr/2010AVIG0238/document.

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Un groupe d'études épidémiologiques fournit une bonne preuve de la relation inverse associé à la consommation de fruits et légumes et les maladies chroniques important comme maladies cardiovasculaires et certains types de cancers. Après les longues années d'études sur phytomacronutrients, le rôle de phytomicronutrients tels que les polyphénols est désormais très étudiée et appréciée dans le contrôle de ces maladies dégénératives. La présente étude combine les études d'extraction, de synthèse et d'analyse sur les principaux polyphénols des fruits d'agrumes, FLAVANONES. Connaissance de nutritionnels et de santé a augmenté la production d'agrumes en provenance des dernières décennies. Ces productions plus générer des bye-produits. Pour leur utilisation alternative à des antioxydants extraits riches, l'extraction assistée par ultrasons (UAE) des polyphénols en particulier flavanones de l'orange (Citrus sinensis L.) par son peau en utilisant l'éthanol comme solvant de qualité alimentaire a été prouvé son efficacité en comparaison avec la méthode conventionnelle . Un plan composite central (CCD) a révélé que l'approche des conditions optimisées pour UAE ont une température de 40 ° C, une puissance de 150W sonication et un 4:1 (v / v) d'éthanol: ratio de l'eau. En outre, l'activité antioxydante déterminée par les tests DPPH et ORAC a confirmé la pertinence des UAE pour la préparation d'extraits de plantes riches en antioxydants.Les glucuronides de flavanone sont les principaux métabolites phénoliques détectés dans le plasma humain après la consommation d'agrumes. Jusqu'à maintenant, toutes les études sur les cellules liées au cancer ou les maladies cardiovasculaires ont été réalisées soit sur les aglycones ou sur leurs glycosides. Par conséquent, il ya grand besoin de glucuronides flavanone pure pour démontrer le potentiel réel de flavanones dans la prévention de ces maladies. Dans ce travail, glucuronides de naringénine (4'- et 7-O-β-D-glucuronides) et de hespérétine (3'- et 7-O-β-D-glucuronides), les aglycones flavanone majeur dans le pamplemousse et d'orange, respectivement, ont été synthétisés chimiquement par une protection et la déprotection sélective des groupements d'acide glucuronique et de flavanone. La caractérisation structurale complète de composés purifiés a été réalisée par résonance magnétique nucléaire et spectrométrie de masse.L'affinité des quatre glucuronides pour l'albumine sérum d’humaine (HSA) a été testée par leur capacité à éteindre la fluorescence intrinsèque de HSA (Trp, seul résidu de sous-domaine IIA). Leurs constantes de fixation (K) ont été estimées de l'ordre de 30 à 60 × 103 M-1 et comparées à celles de l'aglycones (70 à 90 × 103 M-1). Les enquêtes de la liaison compétitive ou non compétitive de la glucuronides dans la présence de sondes fluorescentes (sarcosine dansyl) nous a permis d'obtenir un aperçu dans les sites de liaison. L'étude a également été étendue aux chalcones hespérétine et naringénine (synthétisés en utilisant des conditions alcalines optimisée), qui sont les précurseurs de biosynthèse des flavanones
A bunch of epidemiological studies provides good evidence on the inverse relationship associated with the consumption of fruits and vegetables and the chronic diseases importantly cardiovascular diseases and some types of cancers. After the long years of study on phytomacronutrients, the role of phytomicronutrients such as polyphenols is now highly studied and appreciated in the control of such degenerative diseases. The present study combines the extraction, synthetic and analytical studies on the major polyphenols of citrus fruits, FLAVANONES.Awareness of nutritional and health facts has increased the production of citrus fruits from last few decades. These higher productions generate higher by-products. For their alternative utilisation to have antioxidants rich extracts, the ultrasound-assisted extraction (UAE) of polyphenols especially flavanones from orange (Citrus sinensis L.) peel by using ethanol as afood grade solvent has been proved its efficiency when compared with the conventional method. A central composite design (CCD) approach revealed that the optimized conditions for UAE were a temperature of 40°C, a sonication power of 150W and a 4:1 (v/v) ethanol:water ratio. Furthermore, the antioxidant activity determined by the DPPH and ORAC tests confirmed the suitability of UAE for the preparation of antioxidant-rich plant extracts. Flavanone glucuronides are the major phenolic metabolites detected in human plasma after consumption of citrus fruits. Up to now all cell studies related to cancer or cardiovascular diseases were conducted either on the aglycones or on their glycosides. Hence, there is great need of pure flavanone glucuronides to demonstrate the real potential of flavanones in the prevention of these diseases. In this work, glucuronides of naringenin (4′- and 7-O-β-D-glucuronides) and hesperetin (3′- and 7-O-β-D-glucuronides), the major flavanone aglycones in grapefruit and orange respectively, have been chemically synthesized by selective protection and deprotection of flavanone and glucuronic acid moieties. The complete structural characterisation of purified compounds were realised by nuclear magnetic resonance and mass spectrometry.The affinity of the four glucuronides for human serum albumin (HSA) was tested via their ability to quench the intrinsic fluorescence of HSA (single Trp residue in sub-domain IIA). Their binding constants (K) were estimated in the range of 30 – 60 × 103 M-1 and compared with those of the aglycones (70 – 90 × 103 M-1). Investigations of competitive or noncompetitive binding of the glucuronides in the presence of fluorescent probes (dansyl sarcosine) allowed us to get some insight in the binding sites. The study was also extended to the hesperetin and naringenin chalcones (synthesised using optimized alkaline conditions), which are the biosynthetic precursors of flavanones

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Pasquel, Reátegui José Luis 1985. "Extração de compostos do bagaço de amora-preta (Rubus sp.) usando CO2 supercrítico assistido por ultrassom." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254632.

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Orientador: Julian Martínez
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A amora-preta (Rubus sp.) tem chamado a atenção de produtores e consumidores nos últimos anos, por ser uma boa fonte de compostos bioativos que oferece benefícios para a saúde. Os resíduos agroindustriais do processamento de amora geralmente têm demonstrado ser uma boa fonte de flavonoides, que são compostos fenólicos amplamente conhecidos pela sua atividade antioxidante. O presente trabalho teve como principal objetivo obter extratos a partir do bagaço de amora-preta usando CO2 supercrítico assistido por ultrassom. Assim, para a extração supercrítica com CO2 puro foi feito um desenho de tipo Box-Behnken, com três variáveis independentes, sendo elas a temperatura (40, 50 e 60 °C), pressão (15, 20 e 25 MPa) e potência ultrassônica (0, 200 e 400 Watts). A vazão de CO2 foi mantida constante em 2,77 x 10-4 kg/s, para todos os experimentos feitos com CO2 puro. O maior rendimento foi encontrado a 50 °C, 25 MPa e 400 Watts de potência ultrassônica. Após selecionada a melhor condição, foi realizado um estudo para determinar os parâmetros cinéticos do processo de extração supercrítica. A composição dos extratos foi avaliada por espectrofotometria, pela qual os maiores teores de fenólicos foram observados a 60 °C, 20 MPa e sem uso de ultrassom. Além disso, observou-se um aumento da atividade antioxidante a 60 °C, 15 MPa e 200 Watts de potência em relação aos demais resultados obtidos pela de extração supercrítica. A fim de comparar o rendimento e composição dos extratos foi adicionado cossolvente na extração supercrítica, na condição de 60 °C, 15 MPa e ultrassom de 200 Watts, selecionada com base na atividade antioxidante presente nos extratos obtidos com CO2 puro. Na avaliação do comportamento dos extratos obtidos pela extração supercrítica com cossolvente, observou-se uma melhoria no rendimento global quando foi empregado etanol a (10 % v/v). Por outro lado, o emprego de água a (10 % v/v) como cossolvente foi mais adequado para a recuperação de compostos fenólicos e atividade antioxidante a partir do bagaço de amora-preta seca triturada. Também foi observado que a matéria-prima sem pré-tratamento algum apresentou maior conteúdo de antocianinas nos extratos obtidos pela extração supercrítica com (5 % v/v) de água como cossolvente. A partir da análise por UPLC-QTOF-MS, foi possível identificar quatro antocianinas; duas majoritárias (Cianidina-3-glucosídeo e Cianidina-3-rutinosídeo) e duas minoritárias (Cianidina-3-malonil-glucosídeo e Cianidina-3-dioxalil-glucosídeo), presentes no bagaço de amora-preta. Por último, observou-se que o emprego de ultrassom provoca efeitos físicos nas paredes das células quando foi analisada a morfologia da matéria-prima antes e após as extrações por microscopia eletrônica de varredura (MEV)
Abstract: Blackberry (Rubus sp.) has attracted the attention of producers and consumers in recent years, since it is a good source of bioactive compounds that offers health benefits. Agro-industrial wastes resulting from blackberry processing have demonstrated to be a good source of flavonoids, which are phenolic compounds widely known for their antioxidant activity. The objective of this work was to produce extracts from blackberry bagasse using supercritical fluid extraction assisted by ultrasound. For the supercritical fluid extraction a Box-Behnken design was performed with extraction pressure (15, 20 and 25 MPa), temperature (40, 50 and 60 °C) and ultrasound output power (0, 200 and 400 W) as independent variables. The CO2 flow rate (2.77 x 10-4 kg/s) was maintained constant for all experiments done with pure CO2. The highest yield was found at 50 °C and 25 MPa with an ultrasound output power of 400 W. After selecting the best process condition, a study was done to determine the kinetic parameters of the supercritical extraction process. The composition of the extracts was estimated by spectrophotometry, and the highest quantities of phenolics compounds were observed at 60 °C and 20 MPa without ultrasound. Furthermore, an increase of the antioxidant activity was observed at 60 °C, 15 MPa and 200 W of ultrasound power in comparison to other results obtained by supercritical extraction. With the objective to compare the yield and the composition of the extracts a cosolvent was added in the supercritical extraction process, at the extraction conditions of 60°C, 15 MPa and 200 W; these process conditions were selected based on the antioxidant activity present in the extracts obtained with pure CO2. An enhancement in the overall yield was observed when ethanol (10 % v/v) was applied as cosolvent. On the other hand, the use of water (10 % v/v) as cosolvent was more appropriate for the recovery of phenolic compounds, anthocyanins and antioxidant activity from dried milled blackberry bagasse. It was also observed that the raw material without any pretreatment showed higher content of anthocyanins in the extracts obtained by supercritical extraction with water (5 % v/v) as cosolvent. From the UPLC-QTOF-MS analyses, it was possible to identify four anthocyanins, two major anthocyanins (cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside) and two minor anthocyanins (cyanidin-3-malil-glucoside and cyanidin-3-diaxial-rutinoside), present in the blackberry bagasse. Finally, when the morphology of the raw material was analyzed before and after the extraction by scanning electron microscopy (SEM), it was observed that the use of ultrasound produced physical changes in the cell walls
Mestrado
Engenharia de Alimentos
Mestre em Engenharia de Alimentos

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Santil, Darlan da Silva. "Determinação de elementos maiores e traço em tecidos de moluscos bivalves por espectrometria de emissão óptica com plasma indutivamente acoplado." Instituto de Química, 2010. http://repositorio.ufba.br/ri/handle/ri/20240.

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O presente estudo propõe a determinação de elementos maiores e traço em invertebrados marinhos por Espectrometria de Emissão Óptica com Plasma Indutivamente Acoplado (ICP OES) após um procedimento assistido por radiação ultrassom e centrífuga, empregando ácidos diluídos. Um planejamento Doehlert de três fatores foi aplicado para otimizar a extração dos elementos nas amostras de bivalves (Mytella guyanensis, Anomalocardia brasiliana e Crassostrea rhizophorae). Os fatores foram: concentração da mistura ácida (HCl + HNO3 + H3CCOOH; 1-3 mol L-1), tempo de centrifugação (10-40 min.), e velocidade de rotação (6000-10000 rpm). A eficiência de extração expressa em percentual foi escolhida como resposta analítica no processo de otimização. Além disso, todos os experimentos foram realizados analisando o material de referência certificado NIST 1566b (tecido de ostra). O percentual de recuperação obtida nas amostras de material de referência certificado pela martiz Doehlert variou de 45-95, 8-52, 35-71, 67-102, 38-78, 61-92, 58-100, 39-85 e 51-91%, respectivamente, para Ca, Cd, Cu, K, Mg, Mn, Na, Sr, e Zn. Todavia, ponto de máximo não foi obtido. Portanto, a resposta múltipla foi escolhida para obtenção dos valores máximos de extração dos metais. As seguintes condições experimentais da resposta múltipla foram selecionadas: 20 min de tempo de extração, 9000 rpm de velocidade de rotação e 1,0 mol L-1 da mistura ácida. A fim de avaliar o efeito do ultrassom na extração dos elementos, uma porção de tecido de ostra certificado foi sonicada por 15 min em um banho de ultrassom à temperatura ambiente e a solução foi centrifugada nas condições otimizadas. Os resultados mostraram que o uso da sonicação antes da centrifugação promoveu um aumento na porcentagem de recuperação dos elementos estudados. A repetitividade do procedimento auxiliado por centrífuga e ultrassom foi avaliada pela determinação de elementos maiores e traço em 10 replicatas do material certificado. Os desvios padrões relativos (RSD) para o procedimento proposto variam entre 1,8 a 4,7. A exatidão do método foi confirmada pela análise de tecido de ostra certificado (NIST 1566b) e por comparação de método analítico de referência com procedimento de digestão ácida para o tratamento das amostras (microondas com cavidade). Os resultaldos da análise da exatidão de alguns elementos estudados mostraram que não havia diferenças significativas (p<0,05) entre o método proposto e o método de referência. Concomitantemente ao desenvolvimento do método analítico, as concentrações dos elementos menores e maiores em amostras dos bivalves coletados ao longo da Baía de Todos os Santos, Bahia, Brasil foram determinadas por ICP OES após o procedimento de digestão ácida em bombas Parr. Os resultados da determinação revelaram que as concentrações de As, Cu e Zn nos bivalves estavam acima dos limites máximos estabelecidos pela ANVISA e por agências especializadas em saúde internacionais. Esses valores de concentração sugerem que deve ser feita uma análise de risco a
The present study proposes the determination of major and trace elements in marine invertebrates by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP OES) after a procedure assisted by ultrasound radiation and centrifugal, employing diluted acids. A three factor Doehlert design was applied to optimize the extraction of elements in bivalves (Mytella guyanensis, Anomalocardia brasiliana and Crassostrea rhizophorae). The factors were: concentration of acid mixture (HCl + HNO3 + H3CCOOH; 1-3 mol L-1), centrifugation time (10-40 min.), and rotation velocity (6000-10000 rpm). The extraction efficiency, expressed as a percentage, was chosen as the analytical response in the optimization process. In addition, all experiments were performed by analyzing the certified reference material NIST 1566b (oyster tissue). The percentage of recovery obtained in the samples of certified reference material by Doehlert varied from 45-95, 8-52, 35-71, 67-102, 38-78, 61-92, 58-100, 39-85 and 51-91%, respectively, for Ca, Cd, Cu, K, Mg, Mn, Na, Sr, and Zn. However, maximum point wasn’t obtained. So, the multiple response was chosen to obtain the maximum extraction of the metals. The following experimental conditions of multiple response were selected: 20 min of extraction time, 9000 rpm of the speed centrifuge and 1.0 mol L-1 of the acid mixture. In order to evaluate the ultrasound effect on the extraction of trace elements a portion of the certified oyster tissue sample was sonicated for 15min in an ultrasonic bath at ambient temperature, and then the solution was centrifuged at the optimized conditions. Results showed that the use of the sonication prior to the centrifugation promoted an increase in the percentage of recovery for most studied elements. The repeatability of the centrifugation and ultra- sound assisted procedure was evaluated by the determination of trace and major elements in 10 replicates of the oyster tissue certified material. The relative standard deviations (RSD) for the centrifugation and ultrasound assisted procedure varied between 1.8 and 4.7%. The accuracy of the method was confirmed by analysis of the certified oyster tissue (NIST 1566b) and by reference analytical method comparison with acid digestion procedure for the sample treatment (microwave cavity). The results of the analysis of the accuracy of some elements studied showed that there were no significant differences (p <0.05) between the proposed method and the reference method. Concurrent with the development of the acid extraction procedure, the major and trace concentrations of elements in mussel, oyster and clams samples collected from along coastal the zones of Todos os Santos Bay were determined by ICP OES after Parr acid digestion bombs. The results of determination showed that concentrations of As, Cu and Zn in the bivalves were above the limits established by ANVISA and international agencies specializing in health. These concentration values suggest that must be a health risk analysis mainly in the communities that collect the shellfish as a subsistence activity.

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Neves, Mônica Araujo das. "DESENVOLVIMENTO E APLICAÇÃO DE METODOLOGIA ANALÍTICA (CLAE/FL) PARA DETERMINAÇÃO DE FLUOROQUINOLONAS EM SEDIMENTO ESTUARINO DA ILHA DO MARANHÃO." Universidade Federal do Maranhão, 2014. http://tedebc.ufma.br:8080/jspui/handle/tede/1000.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Drugs in the planet have increased during last decades. Such compounds can cause adverse impact on ecosystems. Soon, more effective analytical methods are essential for the study of new pollutants, especially in magazines whose headquarters are very complex as mangrove sediments. Therefore, this study aimed to improve an analytical method to assess the occurrence of fluoroquinolone antibiotics, ciprofloxacin (CIP), levofloxacin (LEV) and norfloxacin (NOR), in sediment samples from the Paciência river located on the Maranhão island using the technique of ultrasound-assisted extraction, extraction phase solid and liquid chromatography (HPLC/FD). According to the study, the method was linear (r²> 0.99), recovery ranging from 73.73 to 88.85%, precise (RSD <20%), selective and sensitive (detection limit for CIP, LEV and NOR 9.32; 17.78 and 4.42 µg.kgˉ¹, respectively, and limit of quantitation of 20 µg.kgˉ¹ for all three drugs) for quantification of fluoroquinolones in estuarine sediments. Other relevant aspects of the method developed in this work were the simplicity, low cost and absence of interfering to a very complex environmental matrix as are the mangrove sediments. When evaluating the sediment at various points of the river there was contamination at three points by CIP ranging from 56.55 to 70.45 µg.kgˉ¹ These results are similar to those found around the planet to polluted regions and they are of concern due to the effects of these antibiotics in the ecosystem.
É crescente a utilização de fármacos no planeta nas últimas décadas. Tais compostos podem causar impacto negativo nos ecossistemas. Logo, métodos analíticos mais eficazes são fundamentais para o estudo de novos poluentes, especialmente em compartimentos cujas matrizes são muito complexas como sedimentos de manguezal. Sendo assim, este trabalho teve por objetivo aprimorar um método analítico para avaliar a ocorrência de antibióticos fluoroquinolônicos, ciprofloxacino (CIP), levofloxacino (LEV) e norfloxacino (NOR), em amostras de sedimento do rio Paciência localizadas na ilha do Maranhão utilizando a técnica de extração assistida por ultrassom, extração em fase sólida e a cromatografia líquida (CLAE/FL). Segundo o estudo, o método mostrou-se linear (r²>0,99), recuperação variando 73,73-88,85%, preciso (DPR < 20%), seletivo e sensível (Limite de detecção para CIP, LEV e NOR de 9,32; 17,78 e 4,42 µg.kgˉ¹, respectivamente e limite de quantificação de 20 µg.kgˉ¹ para todos os três analitos) para quantificação de fluoroquinolonas em sedimento estuarino. Outros aspectos relevantes do método desenvolvido nesse trabalho foram à simplicidade, o baixo custo e ausência de interferentes para uma matriz ambiental muito complexa como são os sedimentos de manguezal. Ao avaliar o sedimento em vários pontos do rio observou-se contaminação em três pontos por CIP variando entre 56,55 70,45 µg.kgˉ¹. Esses resultados são similares ao encontrados ao redor do planeta para regiões poluídas e são motivos de preocupação em função dos efeitos desses antibióticos no ecossistema.

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Rohanifar, Ahmad. "Conductive Polymers for Electrochemical Analysis and Extraction." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544809010837595.

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Santos, Kátia Andressa. "Estudo dos processos de extração do óleo de candeia (Eremanthus erythropappus) com fluidos pressurizados e solvente assistido por ultrassom." Universidade Estadual do Oeste do Paraná, 2018. http://tede.unioeste.br/handle/tede/3579.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Candeia (Eremanthus erythropappus) is a native species of the Brazilian Atlantic forest from which an essential oil with high concentration of sesquiterpene α-bisabolol is extracted. α-Bisabolol is an active principle of important application in the cosmetic and pharmaceutical industries due to its anti-inflammatory, antispasmodic, sedative, antiallergic, anti-irritant, cicatrizant and vermifugal properties. Steam distillation is the most common method used to obtain this oil, with requires long periods of time extraction besides the degradation of thermosensitive compounds. Within this context, the aim of this study was to evaluate the quality of the candeia wood oils obtained by non-conventional methods of extraction (supercritical technology by using carbon dioxide and cosolvents, pressurized liquid and ultrasound-assisted extraction), in terms of oil yield, bisabolol content and antioxidant activity. In addition, the oil re-extraction from the industrial residue was also evaluated. The extractions were carried out with CO2 at temperatures of 40, 55 and 70 oC and pressures of 160, 200 and 240 bar, with a solvent mass flow rate of 1.96 x 10−3 kg min−1 and 120 min of total extraction. The highest extraction yield obtained was 1.42 wt% for the candeia wood and 0.41 wt% for the residue, both at 70 oC and 240 bar, and this condition was selected to perform the extractions using cosolvents. Ethanol and ethyl acetate were added to supercritical CO2 at concentrations of 1, 3 and 5 % (v/v), obtaining up to 2.35 wt% of yield. The Soxhlet (360 min) and pressurized liquid (40, 55 and 70 oC; 100 bar and 20 min) extractions showed the affinity of the candeia compounds for polar solvents and the positive effect of the temperature on the yield, which varied from 0.53 to 7.23 wt%. A Box-Benhken design was employed to evaluate the effect of the variables temperature (40, 50 and 60 oC), n-hexane volume to wood mass (10, 15 and 20 mL g-1) and nominal power (150, 300 and 450 W) on the yield of ultrasound-assisted extractions, obtaining in 7 minutes of extraction, up to 83% of the yield obtained in the conventional technique in Soxhlet (1.57 wt%), with a solvent volume 2.5 times smaller. The major compounds identified in the candeia oil were the sesquiterpenes α-bisabolol, eremanthin and costunolide, and the α-bisabolol content in the oil is favored by the lowest CO2 density, with 74.45 % being obtained for the candeia wood and 50.62 % for the residue, in both cases in oil extracted at 70 oC and 160 bar. The addition of ethanol and ethyl acetate cosolvents to CO2 increased the α-bisabolol yield by 41 %. Also, the cosolvents increased the amount of total phenolic content in the oil, and consequently, its antioxidant capacity. The oil fractionation by column chromatography was efficient for α-bisabolol isolation. However, unlike the candeia wood oil, this compound was not effective in inhibiting the Staphylococcus aureus growth. In relation to the supercritical extractions, the Sovová mathematical model presented a good adjustment to the experimental data for all the conditions used.
A candeia (Eremanthus erythropappus) é uma árvore nativa da Mata Atlântica da qual se extrai um óleo essencial com elevada concentração do sesquiterpeno α-bisabolol, princípio ativo de grande aplicação nas indústrias de cosméticos e farmacêutica devido às suas propriedades anti-inflamatória, antiespasmódica, sedativa, antialérgica, anti-irritante, cicatrizante e vermífuga. A obtenção deste óleo em escala industrial é realizada pelo processo de destilação por arraste a vapor, com elevado tempo de extração, além da degradação de compostos termossensíveis. Neste contexto, o presente trabalho tem como objetivo avaliar a qualidade dos óleos da madeira de candeia, obtidos por métodos não convencionais de extração (tecnologia supercrítica com dióxido de carbono e cossolventes, líquidos pressurizados e solvente assistido por ultrassom), em termos de rendimento, teor de α-bisabolol e atividade antioxidante. Ainda, avaliar a re-extração do óleo do resíduo industrial. As extrações foram realizadas com CO2 nas temperaturas de 40, 55 e 70 oC e pressões de 160, 200 e 240 bar, com vazão mássica de solvente de 1,96 x 10-3 kg min-1 e tempo total de 120 minutos. O maior rendimento obtido para o óleo da candeia nas extrações supercríticas foi de 1,42 % e de 0,41 % para o resíduo, ambos em 70 oC e 240 bar, condição selecionada para os experimentos com cossolventes. Os solventes etanol e acetato de etila foram utilizados nas concentrações de 1, 3 e 5 % (v/v) junto ao CO2, proporcionando rendimentos de até 2,35 %. As extrações Soxhlet (360 min) e com líquidos pressurizados (40, 55 e 70 oC; 100 bar e 20 min) evidenciaram a afinidade dos compostos por solventes polares e o efeito positivo da temperatura sobre o rendimento, de 0,53 a 7,23 %. Um planejamento Box-Behnken foi empregado para avaliar efeitos da temperatura (40, 50 e 60 oC), razão volume de n-hexano/massa de madeira (10, 15 e 20 mL g-1) e potência ultrassônica nominal do equipamento (150, 300 e 450 W) sobre rendimento em óleo, obtendo-se, em 7 minutos de extração, até 83 % do rendimento obtido na técnica convencional em Soxhlet (1,57 %), com volume de solvente 2,5 vezes menor. Os compostos majoritários identificados no óleo da candeia foram os sesquiterpenos α-bisabolol, eremantina e costunolida, e o conteúdo do α-bisabolol no óleo foi favorecido pela menor densidade do CO2 supercrítico, sendo de até 74,5 % para a madeira de candeia e 50,6 % para o resíduo, ambos extraídos na condição de 70 oC e 160 bar. A adição dos cossolventes etanol e acetato de etila ao CO2 elevou o rendimento de α-bisabolol em até 41 %. Também aumentaram a quantidade de fenólicos totais no óleo e, consequentemente, sua capacidade antioxidante. O fracionamento do óleo por cromatografia em coluna foi eficiente para o isolamento do α-bisabolol. No entanto, diferentemente do óleo da madeira de candeia, este composto não foi efetivo na inibição do crescimento de Staphylococcus aureus. Em relação às cinéticas das extrações supercríticas, o modelo matemático de Sovová se ajustou aos dados experimentais em todas as condições utilizadas.

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Khadhraoui, Boutheina. "éco-extraction assistée par ultrasons des plantes médicinales : mécanisme(s), intensification et industrialisation ULTRASOUND TECHNOLOGY FOR FOOD PROCESSING, PRESERVATION AND EXTRACTION Histo-cytochemistry and scanning electron microscopy for studying spatial and temporal extraction of metabolites induced by ultrasound. Towards chain detexturation mechanism Microscopic imaging as a tool to target spatial and temporal extraction of bioactive compounds through ultrasound intensificationUltrason. Review of Alternative Solvents for Green Extraction of Food and Natural Green solvents for analytical chemistry." Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG0715.

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Le retour à la naturalité a favorisé le développement des compléments alimentaires à base de ressources végétales qui apparaissent comme un réservoir quasi-infini de nutriments et de substances naturelles bioactives. Ceci fait de l’extraction solide/liquide une étape incontournable au sein des industries intéressées par ce type de molécules. Avec les préoccupations environnementale set sociétales, il est devenu nécessaire d’inventer et développer de nouveaux procédés qui répondent aux six principes de l’éco-extraction. Cette démarche a totalement inspiré cette thèse qui a pour principal objectif le développement d’une technique d’éco-extraction assistée par ultrasons en substitution de la technique conventionnelle. Ce travail a permis de montrer qu’il était possible d’intensifier l’extraction de composés d’intérêt en utilisant les ultrasons avec une meilleure sélectivité et de meilleurs rendements d’extraction. Une attention particulière a été accordée à la compréhension des mécanismes d’action des ultrasons via une étude macroscopique et microscopique approfondie des structures végétales. Cette investigation a prouvé que les ultrasons agissent différemment en fonction des structures végétales et de leurs propriétés morphologiques et chimiques qui leur confèrent un degré de résistance plus ou moins important face à l’action des ultrasons. Partant de ces résultats, l’étude macroscopique et microscopique a été définie comme un outil de décision pour une extraction ciblée. Cette variabilité a été aussi constatée à l’échelle industrielle prouvant davantage l’importance de l’analyse microscopique. Enfin, le procédé d’extraction par ultrasons a été adopté à l’échelle industrielle pour ses performances d’extraction et pour son empreinte environnementale significativement réduite par rapport au procédé CV. Ce travail a également conduit à des travaux complémentaires sur l’étude du potentiel de solubilisation des produits naturels en vue d’une utilisation pour l’extraction de composés végétaux difficiles à solubiliser dans l’eau. Des résultats prometteurs ont été obtenus en termes de pouvoirs de solubilisation et d’extraction notamment à partir de la matière végétale broyée. Les résultats de cette dernière partie soulèvent cependant des questions qui pourraient faire l’objet de futures recherches et de perspectives pour ce travail qui sont principalement liés à l’étude des problèmes liés au changement du solvant et au prétraitement de la matière première et de la faisabilité industrielle de ce nouveau procédé
With recent trends in the increasing interest to environmental, economic and safety considerations,extraction techniques have largely focused on finding solutions with sustainable and green values toimplement in food processing, cosmetic and pharmaceutical industries. In this context, new “green”extraction techniques were developed such as Ultrasound-Assisted Extraction (UAE). The mainobjective of this thesis is industrial implementation of this new process in substitution to theconventional (CV) process. It has been shown in this work that the extraction of compounds ofinterest from rosemary and other plant matrices could be intensified using ultrasound, and thatdifferent performance gain could be achieved according to the plant matrix structural properties.Indeed, macroscopic and microscopic investigation of untreated and treated raw materials provedthat US act through different mechanisms and its resulting impacts can be extremely limited by plantstructural morphological and chemical properties, especially those of the specialized structures.Significant variability in performance gain was also observed at the industrial scale. Overall, USappears as a promising technique with a significant performance gain in terms of extraction yield andselectivity. Moreover, this process presents low environmental footprint compared to the CV one.Finally, it has been shown that natural products, such as honey and fruit juices, can be used toimprove solubilization and extraction of molecules that are poorly soluble in water. Encouragingresults were obtained in terms of solubilization and extraction abilities, especially from ground rawmaterials. However, these results raise questions related to the feasibility of industrialimplementation of this new process

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Veggi, Priscilla Carvalho. "Obtenção de compostos fenólicos de plantas brasilieras via tecnologia supercrítica utilizando cossolventes e extração assistida por ultrassom." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254865.

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Orientador: Maria Angela de Almeida Meireles
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este estudo teve como finalidade utilizar a extração supercrítica (SFE = supercritical fluid extraction) para obtenção de compostos fenólicos presentes em plantas nativas brasileiras de elevado potencial econômico. As plantas estudadas foram: Cipó-de-são-joão (Pyrostegia venusta), Nó-de-cachorro (Heteropteris aphrodisiaca O. Mach), Ingá Cipó (Inga edulis), Jatobá (Hymenaea courbaril var. stilbocarpa) e Feijão (Phaseolus vulgaris L.). Experimentos de rendimento global (X0,S/F=50) utilizando CO2 puro, CO2 + etanol (10 %, massa) e CO2 + água (10 %, massa) como solventes foram realizados a 35 MPa e 323 K; a razão da massa de CO2 para a massa de alimentação foi mantida constante (50 kg/kg). Posteriormente os extratos foram analisados por cromatografia em camada delgada (CCD); foram determinadas também a atividade antioxidante, o teor de polifenóis e o de flavonoides totais. Após a avaliação do comportamento dos extratos quanto ao tipo de solvente utilizado e análises realizadas, observou-se que o solvente CO2 + H2O resultou em maior rendimento em extrato, especialmente para os de jatobá; adicionalmente, o extrato desta planta teve excelentes características antioxidantes. Desta forma, os estudos posteriores foram realizados com o jatobá. Para selecionar a temperatura e a pressão ótimas de operação, isotermas de rendimento global (IRG's) foram determinadas nas temperaturas de 323 e 333 K e pressões de 15, 25 e 35 MPa. Em função do maior teor de polifenóis e taninos totais obtidos, foi selecionada a pressão de 15 MPa e temperatura de 323 K para estudos da cinética de extração. Curvas cinéticas (OEC = overall extraction curve) foram construídas visando à determinação dos parâmetros de processo através do ajuste das OECs a um spline linear com 3 retas. Em seguida, realizou-se um estudo do aumento de escala, mantendo constantes a razão entre massa de solvente e massa de matéria-prima (S/F) e tempo de processo. As análises químicas dos extratos obtidos por SFE foram realizadas por Cromatografia Líquida de Ultra Eficiência acoplada ao Espectrômetro de Massas em série (UPLC-MS/MS) e Espectrometria de Massas com Ionização por Eletrospray (IES-MS/MS). De acordo com os resultados, os extratos apresentaram perfil químico de procianidinas. Por último, foi determinado o custo de manufatura (COM) dos extratos das cinco plantas obtidos nos ensaios de rendimento global (X0, S/F=50) para os três solventes: CO2 puro, CO2 + etanol (10 %, massa) e CO2 + água (10 %, massa), e do extrato de jatobá no processo otimizado (OEC's) para o solvente CO2 + H2O. O COM estimado demonstrou a viabilidade do processo SFE para unidades industriais com extratores de 50 e 500 L, dependendo da matéria-prima a ser processada. Segundo o COM estimado, a obtenção de extratos ricos em taninos das cascas de jatobá foi economicamente viável para o solvente CO2 + H2O. Adicionalmente, extratos da casca de jatobá foram obtidos utilizando a extração assistida por ultrassom (UAE). As extrações foram realizadas com potência de ultrassom de 20 e 60 W durante 40 min, utilizando a água em uma razão S/F igual a 20 (otimizada em um ensaio de extração por maceração). Maior quantidade de polifenóis foi obtida com a potência de 60 W. A eficiência da UAE na extração de polifenóis foi avaliada através de extrações em corrente cruzada em três estágios; foi estudado o aumento de escala em extrator de 3 litros. Os resultados foram comparados com os obtidos com extração por agitação (AGE) e sonda de ultrassom (UP) utilizando as mesmas condições da UAE. Foi realizado ainda um estudo cinético avaliando a obtenção de polifenóis da casca de jatobá para os processos UAE e AGE. Os extratos foram analisados por CCD; a atividade antioxidante e teor de polifenóis dos extratos foram determinados. Os resultados provaram que a UAE é um método eficiente para obter extratos ricos em compostos fenólicos e com elevada atividade antioxidante. Através da análise química com Cromatografia de Alta Eficiência com detecção por arranjo de diodos (CLAE/DAD), o perfil de compostos fenólicos da casca de jatobá obtidos por UAE constituiu de procianidinas, a (+)-catequina e a (-)-epicatequina
Abstract: The objective of this study was to use supercritical fluid extraction (SFE) to extract phenolic compounds from indigenous Brazilian plants with high economic potential. The plants studied were: Flame wine (Pyrostegia venusta), Dog's knot (Heteropteris aphrodisiaca O. Mach), Ice-cream bean tree (Inga edulis), Jatoba (Hymenaea courbaril var. stilbocarpa) and beans (Phaseolus vulgaris L.). Global yields experiments (X0,S/F=50) using pure CO2, CO2 + ethanol (10 %, mass) and CO2 + water (10 %, mass) as solvents were performed 35 MPa and 323 K; the ratio of the CO2 mass to feed mass was maintained constant (50 kg/kg). The extracts were analyzed by thin layer chromatography (TLC). Their antioxidant activity, total polyphenolic and flavonoids content were also determined. After evaluating the behavior of the yield and chemical composition of the extracts, it was observed that the solvent mixture CO2 + H2O provided higher yield, especially for jatobá. Additionally, this extract presented high antioxidant activity. Based on these results, global yields isotherms (GYI) of jatoba were determined at temperature of 323 and 333 K and pressures of 15, 25 and 35 MPa in order to select the optimum operational conditions. Due to the higher polyphenols and tannins content, the optimum conditions selected were 15 MPa and 323 K. Overall extraction curves (OEC¿s) were obtained under these conditions in order to determine the kinetic parameters by fitting the OECs to a linear spline with three straight lines. For the scale-up study, the criterion adopted was keeping constant the solvent to feed ratio (S/F) and process time. The chemical analyses of SFE extracts were performed by Ultra performance liquid chromatography - diode array detection (UPLC-MS/MS) and electrospray ionization mass spectrometry (ESI-MS/MS). According to the results, the extracts showed chemical profile of procyanidins. Finally, it was evaluated the cost of manufacturing (COM) of the extracts for all five plants obtained in the GYI experiment (X0, S/F=50) for the three solvent: CO2 pure, CO2 + ethanol (10 %, mass) e CO2 + water (10 %, mass); and for the jatobá extract obtained at optimized process conditions using CO2 + water (10 %, mass). The estimated COM demonstrated the feasibility of the SFE process for industrial scale extractors of 50 and 500 L, depending on the raw material to be processed. Moreover, according to the estimated COM, obtaining jatobá bark extracts rich in tannins was economically feasible with CO2 + H2O. Jatoba extracts were also obtained using ultrasound assisted extraction (UAE). The extractions were performed at the potency of 20 and 60 W during 40 min, using water at S/F ratio of 20 (optimized in a maceration extraction assay). High content of polyphenols were obtained using the potency of 60 W. The efficiency of UAE in extracting polyphenols was evaluated using crosscurrent extraction in three stages. The scale-up of the UAE process was studied in an extractor of three liters. It was also performed a kinetic study to evaluate the extraction of polyphenols from jatobá via UAE and AGE. The results were compared to those obtained by extraction under agitation (AGE) and ultrasound probe (UP), in the same conditions used for the UAE experiment. The extracts were analyzed by TLC. The antioxidant activity and polyphenols content of the extracts were also determined. The results proved that UAE is an efficient method to obtain extracts rich in phenolic compounds and with high antioxidant activity. The chemical analysis of the extracts by high performance liquid chromatography - diode array detection (HPLC-DAD), showed that the phytochemical profile of jatobá bark extracts presented procyanidins, (+)-catechin and (-)-epicatechin
Doutorado
Engenharia de Alimentos
Doutora em Engenharia de Alimentos

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Péroumal, Armelle. "Caractérisation des fruits et de la pulpe de six accessions de Mammea americana : Aptitude à la transformation des fruits et caractérisation des composés phénoliques de la pulpe." Thesis, Antilles-Guyane, 2014. http://www.theses.fr/2014AGUY0702/document.

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Dans cette étude, nous nous sommes intéressés aux propriétés physiques et chimiques de six accessions de Mammea americana afin de pouvoir identifier les accessions les plus prometteuses pour la vente en frais ou la transformation. Nous avons également cherché à évaluer l’activité antioxydante de la pulpe, identifier et quantifier ses composés phénoliques et optimiser leur extraction à l’aide de la technique assistée par ultrasons.Nos résultats montrent que les accessions étudiées présentent des caractéristiques physiques, physico-chimiques et fonctionnelles significativement différentes. Pavé 11, Lézarde et Ti Jacques sont intéressants pour la vente en frais, en raison de leurs fruits sucrés avec une teneur élevée en caroténoïdes et composés phénoliques totaux. Sonson, Pavé 11 et Lézarde présentent une adaptabilité à la transformation. La composition polyphénolique de la pulpe déterminée par HPLC-DAD et UPLC-MS, a mis en évidence la présence d’acides phénoliques, de tanins condensés, de flavonols et flavanols dans nos échantillons. D’autre part, les tests d’activité antioxydante (DPPH et ORAC) révèlent que Ti jacques est l’extrait le plus actif. Un plan d’expérimentation a été mis en œuvre afin d’optimiser l’extraction des polyphénols à l’aide d’une technique d’extraction assistée par ultrasons. Les résultats montrent que l’extrait obtenu est riche en polyphénols et contient les mêmes teneurs en acides phénoliques et flavonols comparé à celui obtenu par la méthode conventionnelle. De plus, l’extrait obtenu à l’aide d’un solvant « vert » possède de bonnes propriétés organoleptiques
Our work focuses on the physical and chemical properties of six mamey apple cultivars in order to select elite cultivars suitable for food processing or as table fruit. The antioxidant activity of the fruit pulp, the identification and quantification of the polyphenols responsible for it, and ultrasound assisted extraction method were also investigated.According to our results, the postharvest routes for every cultivar could be different. Pavé 11, Lézarde and Ti Jacques were found to be good for consumption, giving sweeter fruits with high total phenolic and carotenoid contents. Sonson, pavé 11 and Lézarde had suitable characteristics for the manufacturing of mamey products. The polyphenolic composition of the pulp determined by HPLC-DAD and UPLC-MS showed the presence of phenolic acids, condensed tannins, flavonols and flavanols. The results of the antioxidant test (DPPH and ORAC) point out that the most antioxidant cultivar was Ti Jacques. The design and optimization of the ultrasound assisted extraction method has done for polyphenols extraction. The results showed that the polyphenols rich extract contains the same content of phenolic acids and flavonols in comparison to the conventional method. Additionally, the dry extract obtained with a “green” solvent, had good organoleptic properties

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Aleksandra, Gavarić. "Savremene metode ekstrakcije očajnice (Marrubium vulgare L.) i sušenje odabranih ekstrakata, hemijski sastav i biološke aktivnosti." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=114456&source=NDLTD&language=en.

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U okviru ove disertacije ispitane su mogućnosti primene savremenih metoda za dobijanje tečnih ekstrakata (ultrazvučna ekstrakcija, mikrotalasna ekstrakcija i ekstrakcija subkritičnom vodom) i lipofilnih ekstrakata (ekstrakcija superkritičnim ugljendioksidom) bogatih polifenolima iz nadzemnog dela očajnice (Marrubium vulgare L.). Tečni ekstrakti su optimizovani primenom eksperimentalnog dizajna i metode odzivne površine, i podvrgnuti su spray drying tehnici sušenja. Tečni i suvi ekstrakti su detaljno ispitani po pitanju hemijskog sastava i biološke aktivnosti, antimikrobne i in vitro antihiperglikemijske aktivnosti.Za svaku od navedenih ekstrakcionih tehnika ispitan je uticaj glavnih parametara: ultrazvučna ekstrakcija (temperatura, vreme ekstrakcije i snaga ultrazvuka), mikrotalasna ekstrakcija (koncentracija etanola, vreme ekstrakcije i snaga mikrotalasa) i ekstrakcija subkritičnom vodom (temperatura, vreme ekstrakcije i koncentracija HCl u ekstragensu). Kod tečnih ekstrakata dobijenih ultrazvučnom i mikrotalasnom ekstrakcijom na optimizovanim uslovima utvrđeno je prisustvo hlorogenske kiseline i kvercetina koji nisu detektovani u maceratima. Ispitana je antimikrobna aktivnost oba ekstrakta i utvrđeno da je B. cereus najosetljiviji bakterijski soj, dok je u slučaju kvasaca S. cerevisiae posebno osetljiv na oba ekstrakta. Pored ove aktivnosti ispitana je i in vitro antihiperglikemijska aktivnost oba ekstrakta prema α-amilazi i α-glukozidazi, pri čemu ultrazvučni ekstrakt pokazuje veću antihiperglikemijsku aktivnost (50,63% inhibira α-amilazu i 48,67% inhibira α-glukozidazu) što se potencijalno može objasniti prisustvom hlorogenske kiseline (33,11 μg/mL) i kvercetina (34,88 μg/mL). U subkritičnom ekstraktu, dobijenom na optimalnim uslovima, detektovano je jedino prisustvo hidroksi metilfurfurala usled čega ovaj ekstrakt nije podvrgnut ispitivanju antimikrobne i antihiperglikemijske aktivnosti.U cilju ekstrakcije lipofilnih komponenata M. vulgare primenjene su destilacija etarskog ulja (0,05%), Soxhlet ekstrakcija (3,23%) i ekstrakcija superkritičnim ugljendioksidom na pritiscima 100, 200 i 300 bar i temperaturama 40, 50 i 60 °C. Najdominantnija komponenta u svim dobijenim superkritičnim ekstraktima je hemotaksonomski marker marubiin koji nije identifikovan u Soxhlet ekstraktu.Tečni ekstrakti dobijeni ultrazvučnom i mikrotalasnom ekstrakcijom na optimizovanim uslovima i macerat su osušeni spray drying tehnikom (uz dodatak 10 i 50% maltodekstrina) u cilju dobijanja stabilnije forme suvog ekstrakta. Suvim ekstraktima su određene najznačajnije fizičke osobine i hemijski sastav kao i antimikrobna i antihiperglikemijska aktivnost kako bi se procenila mogućnost njihove inkorporacije u funkcionalnu hranu, dijetetske suplemente ili u formulaciji različitih gotovih proizvoda koji se primenjuju preventivno ili radi poboljšanja zdravlja ljudi.
Within the scope of this dissertation, the possibilities of applying modern methods for obtaining liquid (ultrasonic extraction, microwave extraction and subcritical water extraction) and lipophilic extracts (extraction with supercritical carbon dioxide) rich in polyphenols from the aboveground part of white horehound (Marrubium vulgare L.) were examined. Liquid extracts were optimized using an experimental design and response surface method, and subjected to spray drying. Liquid and dry extracts have been extensively examined for their chemical composition and biological activity, antimicrobial and in vitro antihyperglycaemic activities.For each of these extraction techniques, the influence of the main parameters was examined: ultrasonic extraction (temperature, extraction time and ultrasound power), microwave extraction (ethanol concentration, extraction time and microwave power) and subcritical water extraction (temperature, extraction time and HCl concentration in the extractant). Liquid extracts obtained by ultrasonic and microwave extraction under optimized conditions revealed the presence of chlorogenic acid and quercetin, which were not detected in macerates. The antimicrobial activity of both extracts was examined and B. cereus was found to be the most sensitive bacterial strain, whereas in the case of yeast S. cerevisiae was particularly sensitive to both extracts. In addition to this activity, the in vitro antihyperglycaemic activities of both extracts against α-amylase and α-glucosidase were investigated, with ultrasound extract showing higher antihyperglycemic activity (50.63% inhibited α-amylase and 48.67% inhibited α-glucosidase) which could potentially be explained by the presence of chlorogenic acid (33.11 μg/mL) and quercetin (34.88 μg/mL). In the subcritical extract, obtained under optimal conditions, only the presence of hydroxy methylfurfural was detected, and this extract was not subjected to antimicrobial and antihyperglycemic activity.For the extraction of lipophilic components of M. vulgare, distillation of essential oil (0.05%), Soxhlet extraction (3.23%) and extraction with supercritical carbon dioxide at pressures of 100, 200 and 300 bar and at temperatures of 40, 50 and 60 ° C were applied. The most dominant component in all the supercritical extracts obtained is the chemotaxonomic marker marubiin, which was not identified in the Soxhlet extract.The liquid extracts obtained by the ultrasound and microwave extraction under optimized conditions and the macerate were spray dried (with the addition of 10 and 50% maltodextrin) to obtain a more stable form of the dry extract. Dry extracts underwent determination of the most important physical properties and chemical composition as well as antimicrobial and antihyperglycemic activities to evaluate their incorporation into functional foods, dietary supplements or in the formulation of various finished dosage forms that are administered preventively or to improve human health.

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Santos, Anai Loreiro dos. "Recuperação de compostos bioativos do resíduo do processamento do café (silverskin) : otimização do processo de extração; caracterização química, capacidade antioxidante e toxicidade dos extratos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180650.

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O silverskin é um resíduo, rico em compostos antioxidantes, como o ácido 5-cafeoilquínico (5-CQA) e a cafeína (CAF), produzido durante a torrefação dos grãos de café. O objetivo deste estudo foi desenvolver uma metodologia de extração, aliando a extração assistida por ultrassom e o planejamento de experimentos, para a recuperação simultânea do 5-CQA e da CAF da silverskin. Os extratos gerados foram caracterizados e tiveram a capacidade antioxidante e a toxicidade investigadas. A metodologia de superfície de resposta e a função Desejabilidade foram empregadas na otimização da extração. A LC-DAD/MSn foi utilizada para a caracterização dos extratos, os métodos de sequestro do radical DPPH e de redução do ferro (FRAP), para avaliar a capacidade antioxidante; enquanto o ensaio da Artemia salina foi usando para avaliar a toxicidade. As condições ótimas de extração foram: 45 % de etanol em água como solvente de extração, razão amostra-solvente 1/20, extração por 7 min a 59 °C, com rendimentos de 5-ACQ e CAF de respectivamente 2,00 e 6,26 mg g-1. No total, 9 derivados clorogênicos foram tentativamente identificados. Os teores de teofilina, ácido cafeico e derivados clorogênicos foram respectivamente: 0,53, 0,06 e 4,40 mg g-1. O extrato demonstrou considerável capacidade antioxidante, com concentração eficiente de 46,87 mg L-1 e capacidade redutora de ferro de 152,71 μM de FeSO4 g-1, além de alta toxicidade. O método desenvolvido obteve rendimento similar ao da extração sólido-líquido para o 5-ACQ.
Silverskin is a waste generated during the coffee beans roasting. This residue has been showing antioxidant compounds, mainly 5-caffeoylquinic acid (5-CQA) and caffeine (CAF). The aim of this study was used the design of experiments and ultrasound-assisted extraction to develop an extraction method for the efficient recovery of 5-CQA and CAF from silverskin, simultaneously. In addition, the optimized extract was characterized, and its antioxidant capacity and acute toxicity were investigated. The response surface methodology and Desirability function were employed to optimize the extraction. The chemical characterization was carry out by LC-DAD/ESI-MSn. Antioxidant capacity was evaluated by DPPH (2, 2-diphenyl-1 picryl hydrazyl) and FRAP (ferric reducing antioxidant power) methods and the acute toxicity by Artemia salina assay. The optimal extraction conditions were 45.0 % ethanol in water, the solid-to-liquid ratio was 1:20, and extraction for 7.0 min at 59 °C. Under optimal conditions, the yield of 5-CQA and CAF were 2.00 and 6.26 mg g-1, respectively. Theophylline, caffeic acid, and total chlorogenic acid concentrations were 0.53, 0.06 e 4.40 mg g-1, respectively and 9 chlorogenic acids were identified in the extract. The extract showed considerable antioxidant capacity, with efficient concentration value of 46,87 mg L-1 in the DPPH assay and 152,71 μM FeSO4 g-1 (FRAP) and high toxicity. The developed extraction methodology showed similar performance as solid-liquid extraction to 5-CQA yield.

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Vardanega, Renata 1988. "Obtenção de saponinas de raízes de ginseng brasileiro (Pfaffia glomerata) por extração dinâmica a baixa pressão assistida por ultrassom." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254915.

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Orientadores: Maria Angela de Almeida Meireles, Diego Tresinari dos Santos
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Espécies do gênero Pfaffia (Amaranthaceae) têm sido comercializadas como substitutas para Panax (ginseng, Araliaceae) e em função da morfologia similar de suas raízes são popularmente conhecidas como ginseng brasileiro. Dentre as espécies de Pfaffia conhecidas, a Pfaffia glomerata é a mais importante, uma vez que esta é a única que possui o composto ?-ecdisona, o qual representa a saponina de maior interesse desta planta, devido a seus efeitos terapêuticos. Atualmente, cápsulas contendo extratos de P. glomerata são comercializadas sob indicação de auxiliar da memória e tônico. Além destas indicações, as raízes desta planta apresentam teores expressivos de saponinas (10-17%), o que faz com que o extrato das raízes de P. glomerata apresente um grande potencial para aplicação como emulsificante/surfactante. Comercialmente, extratos de P. glomerata são obtidos por percolação em leito fixo, no entanto, com baixos rendimentos. O objetivo deste estudo foi obter um extrato de ginseng brasileiro (P. glomerata) rico em saponinas empregando o processo de extração por percolação a baixa pressão, o qual é um processo de extração já estabelecido comercialmente, sob a assistência do ultrassom, que vem se destacando como uma técnica emergente na melhoria de processos de extração. Deste modo, as variáveis resposta estudadas foram o rendimento global de extração (X0) e as propriedades emulsificantes/surfactantes dos extratos obtidos: Índice de emulsificação (E24) e redução da tensão superficial da água (RTSA); os parâmetros avaliados foram: método de extração (percolação, PE; percolação assistida por ultrassom durante toda extração, PEU; percolação assistida por ultrassom durante o início da extração, PEUI e percolação assistida por ultrassom com pulsos, PEUP), temperatura (40 e 60°C) e solventes (água; etanol:água [35:65, v/v]; etanol:água [70:30, v/v], isopropanol:água [35:65, v/v] e isopropanol:água [70:30, v/v]). As condições de extração que proporcionaram maiores valores de X0 (62,8%), E24 (54,4%) e RTSA (36,3%) foram água, 60°C, PEUP; isopropanol:água (70:30, v/v), 60°C, PEUP e isopropanol:água (70:30, v/v), 60°C, PEUI, respectivamente. Estas condições foram selecionadas para estudo cinético e obtenção de parâmetros cinéticos ajustados que mostraram que, quando água foi empregada como solvente de extração sob ultrassom, obteve-se a maior recuperação de extrato com menor tCER (período de taxa de extração constante). Portanto, a condição de extração com água, 60°C, PE, representa a condição ótima em termos de rendimento. Ainda, realizou-se a quantificação do teor de ?- ison nos xtr tos o ti os n s in ti s on o t v -s -14% (base seca) de ?-ecdisona nos extratos das raízes de P. glomerata. A condição de extração que proporcionou os extratos com maior teor de ?-ecdisona foi a isopropanol:água (70:30), 60°C, PEUI, comprovando a maior seletividade de extração da mistura de solventes isopropanol:água (70:30, v/v), já que este foi também o solvente que apresentou extratos com maiores propriedades surfactantes. Portanto, pode-se concluir que ao final deste estudo, ao empregar o método de percolação em leito fixo assistida por ultrassom no início da extração utilizando isopropanol:água (70:30) como solvente de extração a 60°C, obteve-se uma condição de extração otimizada que fornece extratos das raízes de P. glomerata com alta recuperação de compostos bioativos
Abstract: Species of the genus Pfaffia (Amaranthaceae) have been commercialized as substitute to Panax (ginseng, Araliaceae). Due to the similar morphology of its roots to those of ginseng, they are popularly known as Brazilian ginseng. Among the species of Pfaffia, the P. glomerata is the most important because it is the only one that contains ?- ecdysone; which is the most important saponin from this plant due their therapeutic effects. Nowadays, capsules containing P. glomerata roots extracts are commercialized under indication to of improving the memory and as a tonic. Besides these indications, the P. glomerata roots exhibit expressive saponins content (10-17%); therefore, its extract can potentially be used as an emulsifier/ surfactant. Commercially, P. glomerata roots extracts are obtained by low-pressure solvent extraction in fixed bed extractors, however, with low yields. The aim of this study was to obtain an extract from Brazilian ginseng roots (P. glomerata) rich in saponins applying the process of low-pressure solvent extraction, which is an extraction process commercially established, assisted by ultrasound ; ultrasound assisted extraction is an emerging technique used to improve extraction process. The effects of the following parameters were evaluated on the overall extraction yield (X0) and surfactant properties (Emulsification index, E24 and reduction of water surface tension, RTSA) of P. glomerata roots extracts: extraction method (percolation, PE; ultrasound assisted percolation during the entire process, PEU; ultrasound assisted percolation at the beginning of the process, PEUI and ultrasound assisted percolation with pulses, PEUP), temperature (40 and 60°C) and extracting solvents (water, ethanol:water [35:65], ethanol:water [70:30], isopropanol:water [35:65] and isopropanol:water [70:30]). The extraction conditions that provided higher values to X0 (water, 60°, PEUP), E24 (isopropanol:water [70:30], 60°C, PEUP) and RTSA (isopropanol:water [70:30], 60°C, PEUI) were selected for the kinetic study; the kinetic parameters were estimated fitting the experimental data to a linear spline with 3 straight lines. The kinetic parameters showed that when water was used as extracting solvent assisted by ultrasound, the higher extract recovery was obtained with the shortest tCER (constant extraction rate period). Therefore, the extraction condition with water, 60°C, PEUP is the optimum condition with respect to the X0. The content of ?-ecdysone was evaluated on the extracts obtained from kinetic study. The content of ?-ecdysone in the P. glomerata roots xtr ts w r -14% (dry base, d.b.). The extraction condition that provided the higher extraction of ?-ecdysone was that using isopropanol:water [70:30], 60°C, PEUI; the extracts with the best surfactant properties were obtained in this extracting condition . Therefore, it was concluded that applying ultrasound at the beginning of process using IsoC3OH:water (70:30) as extracting solvent at 60°C, was the optimized extraction condition to obtain extracts from P. glomerata roots
Mestrado
Engenharia de Alimentos
Mestra em Engenharia de Alimentos

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Chandrasekaran, Vigna Nivetha. "Development and characterisation of starch and polyphenols for functional enhancement in high value food products from lontan vegetables." Thesis, La Réunion, 2020. http://www.theses.fr/2020LARE0023.

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Les cultures de racines et tubercules jouent un rôle important, diversifié et complexe dans l'alimentation des populations. Ces cultures ont le potentiel d'éradiquer la pauvreté et d'améliorer la sécurité alimentaire. L'amidon est le principal composant des racines et des tubercules. L'importance de l'amidon en tant que matière première dans les industries alimentaires et non alimentaires augmente. Dans la présente étude, l'efficacité de l'extraction assistée par ultrasons (EAU) pour augmenter le rendement d’extraction de l’amidon et des polyphénols à partir des légumes lontan (Canna et manioc) a été analysée ainsi que son influence sur les propriétés physico-chimiques des composés extraits. Les paramètres d'extraction (température, temps, rapport solide : liquide) ont été optimisés grâce à la conception de surface de réponse Box Behnken (BBD). Les propriétés physicochimiques et fonctionnelles de l'amidon et des polyphénols ont été étudiées par SEM, indice de gonflement et de solubilité, indice d'absorption d'huile et d'eau, rendement total en polyphénols, dosage DPPH et ORAC. Les rendements en amidon obtenu à partir du canna et du manioc aux conditions d'extraction optimales (Canna : température 40 ° C, durée 10 min, rapport solide : liquide 1:30 g / ml ; Manioc : température 40 ° C, durée 10 min, rapport solide : liquide 1:25 g / ml) étaient respectivement de 19,81% et 16,51%. Nous avons mis en évidence que le rendement en amidon obtenu était significativement plus élevé que le rendement atteint par la méthode d'extraction conventionnelle sans aucun changement significatif ou défavorable de ses propriétés physico-chimiques et fonctionnelles. Les rendements d’extraction des polyphénols du canna et du manioc étaient de 1061,72 mg GAE / & 100g et 7644,46 mg GAE / & 100g respectivement. Le rendement total en polyphénols obtenu par EAU s'est révélé significativement plus élevé que pour la méthode conventionnelle. L'activité antioxydante des composés bioactifs analysés par DPPH et ORAC s'est avérée être directement proportionnelle au rendement en polyphénol. Les résultats que nous avons obtenus suggèrent que les EAU augmenter les rendements d’extraction en amidon et en polyphénols sans altérer les propriétés des composés isolés
Roots and Tuber crops plays an eminent, countless and complex part in feeding the world. These crops have the potential to eradicate poverty and improve food security. Starch is the principal component of roots and tuber crops. The significance of starch as a raw material in both food and non-food industries are increasing. In present study efficiency of ultrasound assisted extraction (UAE) to increase the yield of starch and polyphenols from lontan (Canna and Cassava) crops were analysed along with its influence on the physiochemical properties of extracted compounds. Extraction parameters (Temperature, time, solid: liquid ratio) were optimized through Box Behnken response surface design (BBD). Physiochemical and functional properties of starch and polyphenols were investigated through SEM, swelling and solubility index, oil and water absorption index, Total polyphenol yield, DPPH and ORAC assay. Starch yield obtained from canna and cassava at the optimum extraction conditions (Canna: temperature 40°C, time 10 min, solid: liquid ratio 1:30 g/ml; Cassava: temperature 40°C, time 10 min, solid: liquid ratio 1:25 g/ml) were 19.81% and 16.51% respectively. Obtained starch yield was found to be significantly higher than the yield attained through conventional extraction method without any significant or adverse changes in the physicochemical and functional properties. Total polyphenol yield from canna and cassava rhizome was 1061.72 mg GAE/&100g and 7644.46 mg GAE/&100g respectively. Total polyphenol yield obtained through UAE was found to be significantly higher than conventional method. Antioxidant activity of bioactive compounds analysed through DPPH and ORAC was found to be directly proportional to the attained polyphenol yield. From the obtained results it can be observed that UAE has the efficiency to increase the yield of starch and polyphenols without altering the properties of isolated compounds

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Klein, Elissandro Jair. "Obtenção de compostos bioativos de folhas de uvaia (Eugenia pyriformis Cambess.) utilizando CO2 supercrítico e extração com solvente assistida por ultrassom." Universidade Estadual do Oeste do Paraná, 2016. http://tede.unioeste.br/handle/tede/3729.

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Eugenia pyriformis Cambess. (Uvaia), typical of the Atlantic Forest belongs to the Myrtaceae family, the same family of cherry, jabuticaba and other plants, currently studied due to their antioxidant, antimicrobial and medicinal properties. The interest in bioactive compounds obtained from natural sources has led to an increase in researches aiming to find these compounds in plant extracts. The extractions using conventional methods generally have some drawbacks, and an interesting alternative has been the use of non-conventional extraction technologies, such as the supercritical fluid and the ultrasound-assisted extraction. This work aims to study unconventional methods of obtaining uvaia extracts in order to obtain extracts rich in bioactive compounds. Factors such as the influence of type of extraction (supercritical fluid and ultrasound) and the used conditions on the yield and composition were evaluated. The results were compared to those obtained using the extraction by maceration, a conventional extraction method. After drying and milling the uvaia leaves, the plant material was subjected to extraction with the supercritical CO2 solvent under different conditions of temperature (40, 50 and 60 °C) and pressure (100, 150 and 200 bar), with a fixed flow of 2.0 kg min-1. In the ultrasound-assisted extraction, the effects of temperature (40, 50 and 60 °C), power (150, 250 and 350 W) and ratio between the mass of leaves and the volume of solvent (1:10, 1:15 and 1:20) were evaluated. The extracts obtained were chemically characterized by GC-MS giving β-amyrin (53.72 % for SFE and 71.25 % for UAE) and α-amyrin (24.63 % for SFE and 22.69 % for UAE) as main compounds. In the supercritical extraction, the pressure and the interaction between pressure and temperature showed statistically significant effects on the yield, with the best result being achieved at 200 bar and 60 °C, reaching 1.69%. The data obtained from the supercritical fluid extraction were used to adjust the extraction curves simulated by using two empirical models available in the literature. The tested models adjusted well to the experimental data and the analysis of the estimated parameters allowed to define which model best describes the kinetics of each experimental condition. For the ultrasound-assisted extraction, the best yield result found in the determination of the kinetics was 1.81% in 40 minutes, although in the experimental design a 3 minute time extraction was used due to the better characteristics showed by the extracts at this time. The best result obtained in experimental design with ultrasound was 1.79% provided 30% power, 60 °C and mas/solvent ratio 1:20. Statistical analysis of the experimental design of the ultrasound-assisted extraction indicated significant effects from the variables temperature, mass/solvent ratio and the interaction between power and mass/solvent ratio. The best results for amyrin content by extract weight was found for supercritical extraction, with 97.43%. The ultrasound-assisted extraction showed the best amyrin amount per mass of leaves, 12.13 g of the mixture of isomers per kg of dry leaf.
Eugenia pyriformis Cambess. (Uvaia), típica da Mata Atlântica pertence à família Myrtaceae, mesma família da pitanga, jabuticaba e outras plantas, atualmente estudadas devido às suas propriedades antioxidantes, antimicrobianas e medicinais. O interesse por compostos bioativos obtidos de fontes naturais tem levado ao aumento no número de pesquisas que visam encontrar esses compostos em extratos de plantas. As extrações que utilizam os métodos convencionais geralmente apresentam inconvenientes, e uma alternativa interessante tem sido a utilização de tecnologias não convencionais de extração, como a extração utilizando fluidos supercríticos e a extração assistida por ultrassom. O presente trabalho tem como objetivo estudar métodos não convencionais de obtenção de extratos de uvaia visando obter-se extratos ricos em compostos bioativos. Foram avaliados fatores como influência do tipo de extração (fluido supercrítico e ultrassom) e das condições utilizadas no rendimento e na composição. Os resultados foram comparados com os obtidos utilizando a extração por maceração, um método convencional de extração. Após secagem e moagem das folhas de uvaia, o material vegetal foi submetido à extração com o solvente CO2 supercrítico sob diferentes condições de temperatura (40, 50 e 60 oC) e de pressão (100,150 e 200 bar), com vazão fixa de 2,0x10-3 kg min-1. Na extração assistida por ultrassom, foram avaliados os efeitos da temperatura (40, 50 e 60 oC), da potência (150, 250 e 350 W) e razão entre massa de folhas e volume de solvente (1:10, 1:15 e 1:20). Os extratos obtidos foram caracterizados quimicamente por CG-EM apresentando com principais compostos β-amirina (53,72 % para EFS e 71,25 % para EAU) e α-amirina (24,63 % para EFS e 22,69 % para EAU). Na extração supercrítica, a pressão e a interação entre pressão e temperatura apresentaram efeitos estatisticamente significativos em relação ao rendimento, sendo que o melhor resultado foi encontrado com 200 bar e 60 oC, obtendo-se 1,69 %. Os dados obtidos na extração com fluido supercrítico foram utilizados para ajustar as curvas de extração simuladas utilizando dois modelos empíricos disponíveis na literatura. Os modelos testados ajustaram-se de forma satisfatória aos dados experimentais e a análise dos parâmetros estimados permitiu definir qual dos modelos melhor se ajustou à cinética de cada condição experimental. Para a extração assistida por ultrassom o melhor resultado de rendimento encontrado na determinação da cinética foi 1,81 % com 40 minutos, porém no planejamento experimental foi utilizado um tempo de extração de 3 minutos pois com esse tempo os extratos apresentavam melhores características, sendo portanto o melhor resultado obtido igual a 1,79 % na condição de 30 % de potência, 60 oC e razão massa/solvente de 1:20. A análise estatística do planejamento experimental da extração assistida por ultrassom indicou efeitos significativos das variáveis temperatura, razão massa/solvente e a interação entre potência e razão massa/solvente. Os melhores resultados de teor de amirina por massa de extrato foi encontrada para a extração supercrítica, com 97,43 %. A extração assistida por ultrassom apresentou a melhor quantidade de amirina por massa de folha, 12,13 g da mistura de isômeros por kg de folha seca.

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Prá, Valéria Dal. "Brassica oleracea var. capitata: EXTRAÇÃO, CARACTERIZAÇÃO QUÍMICA E ATIVIDADE BIOLÓGICA DE METABÓLITOS SECUNDÁRIOS." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/5969.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The main objective of this work was to evaluate the antioxidant and antibacterial activities of extracts of Brassica oleracea var. capitata, obtained by supercritical CO2 and ultrasound-assisted extractions, as well as to carry out the characterization of these extracts using gas chromatography coupled with mass detector. For supercritical CO2, five extractions were performed to investigate the influence of pressure (10-25 MPa) and temperature (20-60°C) on the extraction yield, chemical composition and antioxidant activity towards peroxyl, superoxide and hydroxyl radicals. The highest extraction yield was 0.47% at 60 °C and 25 MPa. In the characterization of the extracts was possible to identify compounds like sulforaphane and iberin nitrile. All extracts showed antioxidant activity for the three radicals, although the highest activity for all radicals was obtained using the extract obtained at 60 °C and 25 MPa (run 2). For the ultrasound-assisted extraction were evaluated the effects of solvent concentration and temperature. The extracts obtained in the optimized extraction condition, were subjected to different hydrolysis conditions before use in biological assays. It was evaluated the antioxidant activity against DPPH, superoxide and peroxyl radicals, besides the antibacterial activity against S. aureus and E. coli. Both crude and hydrolyzed extracts were characterized by gas chromatography coupled with mass detector. The best condition for extraction was 30 ° C and 60% (w /v) of ethanol. All extracts showed antioxidant activity towards DPPH, superoxide and peroxyl radicals, but the use of hydrolyzed extracts improved considerably the antioxidant activities. Antibacterial activity was detected only in extracts hydrolysates Brassica oleracea var. capitata. The main contributions of this work were that the use of supercritical CO2 extraction to obtain bioactive compounds from Brassica oleracea var. capitata showed a promising alternative to conventional methods of extraction, since it allowed the extraction of compounds of interest in science and industry. Besides, in this work was demonstrated that the hydrolysis of extracts can increase the antioxidant activity of plant extracts.
O objetivo principal deste trabalho foi avaliar a atividade antioxidante e antibacteriana de extratos de Brassica oleracea var. capitata, obtidos a partir de extração supercrítica e extração por ultrassom, além de caracterizá-los por cromatografia gasosa acoplada à detector de massas. Para os compostos bioativos apolares de Brassica oleracea var. capitata, utilizou-se extração com CO2 supercrítico e avaliou-se o potencial antioxidante dos extratos. Foram realizadas cinco extrações para investigar a influência da pressão (10 - 25 MPa) e temperatura (20 - 60°C) no rendimento da extração, na composição química e na atividade antioxidante frente os radicais peroxila, superóxido e hidroxila. Obteve-se o maior rendimento de extração 0,47% a 60 °C e 25 MPa. Na caracterização dos extratos foi possível a identificação de compostos como sulforafano e iberin nitrila. Todos os extratos apresentaram atividade antioxidante para os três radicais, porém a maior atividade para todos os radicais foi o extrato obtido a 60°C e 25 MPa. Para os compostos bioativos polares, otimizou-se a extração assistida por ultrassom. Os extratos obtidos nas melhores condições de extração foram submetidos a diferentes condições de hidrólise, antes da sua utilização nos ensaios biológicos. Avaliou-se a atividade antioxidante, frente ao radical DPPH, superóxido e peroxila, além da atividade antibacteriana, frente a S.aureus e E.coli. Tanto os extratos brutos quanto os hidrolisados, foram caracterizados por cromatografia gasosa acoplada à detector de massas. A melhor condição de extração foi a 30ºC e 60% (m/v) de etanol. Todos os extratos apresentaram atividade antioxidante frente aos radicais DPPH, superóxido e peroxila, mas o uso de extratos hidrolisados melhorou consideravelmente a atividade antioxidante. Em relação à atividade antibacteriana, apenas uma amostra, que foi submetida à condição de hidrólise alcalina apresentou ação frente a E.coli. Uma das principais contribuições deste trabalho foi que a utilização de extração com CO2 supercrítico, para obtenção de compostos bioativos de Brassica oleracea var. capitata, mostrou ser uma alternativa promissora em relação aos métodos convencionais de extração, pois permitiu a extração de compostos com interesse científico e industrial. Além disso, foi demonstrado que a hidrólise dos extratos pode aumentar consideravelmente a atividade antioxidante de extratos vegetais em relação aos extratos brutos.

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27

Abdulhakim, Naffati. "Iskorišćenje sporednog proizvoda uve (Arctostaphylos uva ursi L.) u cilju dobijanja novih biljnih ekstrakata savremenim tehnikama ekstrakcije." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=108225&source=NDLTD&language=en.

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U okviru ove doktorske disertacije ispitana je mogućnost ekstrakcije bioaktivnih jedinjenja iz biljne prašine A. uva-ursi, koja nastaje kao sporedni proizvod u fabrici filter čaja. Za ekstrakciju bioaktivnih jedinjenja primenjene su različite tehnike ekstrakcije (klasična ekstrakcija, ultrazvučna ekstrakcija i ekstrakcija subkritičnom vodom), kao i različiti ekstragensi: voda na sobnoj temperaturi, 30-70% etanol i subkritična voda. Sadržaj bioaktivnih jedinjenja u ekstraktima ispitan je primenom odgovarajućih spektrofotometrijskih metoda i HPLC metode. U ekstrakciji biljne prašine A. uva-ursi detaljno je matematički analiziran uticaj procesnih parametara na ekstrakciju subkritičnom vodom bioaktivnih jedinjenja iz materijala ovog tipa i u tom smislu je posmatran uticaj temperature, vremena i dodatka kiseline, a takođe su određeni uslovi pri kojima je, primenom ove tehnike, moguće ostvariti maksimalnu ekstrakciju bioaktivnih jedinjenja od značaja. Pored toga prikazana je i mogućnost primene spray drying tehnike za sušenje tečnih i proizvodnju suvih ekstrakta A. uva-ursi u formi praha. Na kraju, na osnovu koncentracije bioaktivnih jedinjenja i njihovog delovanja, dat je predlog nekoliko novih preparata na bazi ekstrakata A. uva-ursi, u tečnoj i čvrstoj formi.
This dissertation investigated the possibility to extract bioactive compounds from A. uva-ursi herbal dust, which occurs as a by-product at the filter-teafactory. Various extraction techniques (classical extraction, ultrasound assisted extraction and subcritical water extraction), were applied for the extraction of bioactive compounds, as well as different solvents: water at room temperature, 30-70% ethanol and subcritical water. The content of bioactive compounds in the extracts was investigated using appropriate spectrophotometric methods and the HPLC method. In the extraction of A. uva-ursi herbal dust a detailed mathematical analysis of the influence of process parameters on subcritical water extraction of bioactive compounds from this type of material was conducted. In this regard the influence of temperature, time and acid addition was observed and the conditions under which it is possible to achieve maximum extraction of significant bioactive compounds, by applying this technique, were determined. In addition, the possibility of applying the spray drying technique for drying the liquid and producing dry A. uva-ursi extracts in the form of powder is also presented. Eventually, based on the concentration of the bioactive compounds and their activity, a proposal for a several new preparations in liquid and solid form, based on A. uva-ursi extracts is given.

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Vernes, Léa. "Mise au point d’un procédé innovant d’éco-extraction assisté par ultrasons d’ingrédients alimentaires à partir de spiruline et transposition à l’échelle industrielle." Electronic Thesis or Diss., Avignon, 2019. http://www.theses.fr/2019AVIG0273.

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Les microalgues sont l’une des ressources renouvelables les plus prometteuses pouvant constituer une alimentation durable future. Grâce à leur diversité de métabolisme, ces microorganismes sont capables de synthétiser une vaste gamme de composés d’intérêt à haute valeur nutritionnelle. Cependant, leur consommation reste limitée du fait de leurs caractéristiques organoleptiques intrinsèques peu attrayantes. Afin de répondre à cette problématique et de lever les verrous, les travaux de cette thèse ont porté sur la mise au point d’un procédé de production d’ingrédient alimentaire à partir de spiruline.Une méthode verte et innovante faisant intervenir la technologie ultrasonore pour l'extraction de protéines à partir d'Arthrospira platensis a été proposée dans une première partie. Il s’agit de la manothermosonication (MTS). Le recours à un plan d’expérience a permis d’optimiser les paramètres d’extraction ; et une modélisation mathématique ainsi que des investigations microscopiques ont mené à une compréhension des phénomènes de transfert de masse d’une part et des effets structurels des ultrasons sur les filaments de spiruline d’autre part. Selon les résultats expérimentaux, la MTS a permis d'obtenir 229 % de protéines en plus (28,42 ± 1,15 g / 100 g MS) par rapport au procédé classique sans ultrasons (8,63 ± 1,15 g / 100 g MS). Avec 28,42 g de protéines pour 100 g de spiruline dans l'extrait, un taux de récupération des protéines de 50 % a été atteint en 6 minutes effectives avec un procédé MTS continu. Partant de ces résultats prometteurs, des pistes d’extrapolation ont été étudiées afin de proposer des outils d’aide à la décision pour l’industrialisation du procédé. Ainsi une procédure d’analyse des risques (HACCP & HAZOP), une étude de coût ainsi que l’impact environnemental du procédé ont été développés dans une seconde partie de ces travaux. Enfin, des voies de valorisation des co-produits d’extraction ont été présentées dans une approche de bioraffinerie
Microalgae are one of the most promising renewable resource for future sustainable food. Thanks to their diversity of metabolism, these microorganisms can synthesize a wide range of compounds of interest with high nutritional value. However, their consumption remains limited because of their intrinsic organoleptic characteristics unattractive. To tackle this problem and to overcome these barriers, this thesis was focused on the development of a production process of food ingredient from spirulina.A green and innovative method using ultrasonic technology for the extraction of proteins from Arthrospira platensis was proposed in a first part. This is the manothermosonication (MTS). The use of an experimental plan made it possible to optimize extraction parameters; and mathematical modeling and microscopic investigations led to an understanding of the mass transfer phenomena on the one hand, and the structural effects of ultrasound on spirulina filaments on the other hand. According to the experimental results, MTS allowed to obtain 229 % more proteins (28.42 ± 1.15 g / 100 g DW) compared to the conventional method without ultrasound (8.63 ± 1.15 g / 100 g DW). With 28.42 g of protein per 100 g of spirulina in the extract, a protein recovery rate of 50% was achieved in 6 minutes with a continuous MTS process. Based on these promising results, extrapolation tracks have been studied in order to propose decision support tools for process industrialization. Thus, a risk analysis procedure (HACCP & HAZOP), a cost study as well as the environmental impact of the process were developed in a second part of this work. Lastly, ways of exploiting by-products have been presented in a biorefinery approach

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29

Li, Haizhou. "Ultrasound and microwave assisted extraction of soybean oil." 2002. http://etd.utk.edu/2002/LiHaizhou.pdf.

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Анотація:

Thesis (M.S.)--University of Tennessee, Knoxville, 2002.
Title from title page screen (viewed on Feb. 26, 2003). Thesis advisor: Lester O. Pordesimo. Document formatted into pages (viii, 68 p. : ill. (some col.)). Vita. Includes bibliographical references (p. 60-67).

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30

Diz, Patrícia do Carmo Claro. "Ultrasound-assisted extraction of mycosterols from Agaricus bisporus L. vs conventional Soxhlet extraction." Master's thesis, 2015. http://hdl.handle.net/10198/12426.

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Ergosterol is the most abundant mycosterol in Agaricus bisporus L. (cultivated mushroom most consumed worldwide) and has high commercial value since, among other applications; it is used by the pharmaceutical industry in the preparation of several drugs. To replace common conventional extraction techniques (e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that the type of solvent, extraction time and ultrasound power alter notably the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All the statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5±0.5 mg ergosterol/100 g dw. However, n-hexane conducted to extracts with higher purity (mg ergosterol/g extract) due to the high affinity for lipophilic compounds. In this work it was also concluded that, to simplify the extraction process under industrial conditions, the saponification step often done in the purification of sterol extracts, can be eliminated, without significant differences in the ergosterol content.
O ergosterol é o micoesterol mais abundante na espécie Agaricus bisporus L. (cogumelo cultivado mais consumido em todo o mundo) e apresenta elevado valor comercial uma vez que, entre outras aplicações, é utlizado pela indústria farmacêutica na preparação de diferentes fármacos. Com o intuito de substituir as técnicas de extração convencionais mais comuns, como por exemplo a técnica de extração por Soxhlet, o presente estudo teve como principal objectivo determinar as condições ótimas de extração assistida por ultrassons para a molécula de ergosterol. Após a realização de vários testes preliminares, os resultados mostraram que os parâmetros tipo de solvente, tempo de extração e potência dos ultrassons alteram consideravelmente a eficiência de extração. Utilizando a metodologia de superfície de resposta, foram desenvolvidos modelos para investigar as condições experimentais favoráveis à maximização da eficiência de extração. Todos os critérios estatísticos demonstraram a validade dos modelos propostos. No geral, a extração assistida por ultrassons com etanol a 375 W durante 15 minutos mostrou ser tão eficiente quanto a extração por Soxhlet, extraindo 671,5 ± 0,5 mg ergosterol/100 g ms. No entanto, a utilização de n-hexano conduziu a extratos com uma pureza superior (mg de ergosterol/g de extrato) uma vez que este solvente apresenta uma maior afinidade para moléculas lipofílicas. Neste trabalho concluiu-se ainda que, no sentido de simplificar o processo de extração em condições industriais, o passo de saponificação frequentemente realizado na purificação de extratos de esteróis, poderá ser eliminado, não alterando significativamente o conteúdo em ergosterol.

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31

Lin, Bo-Yu, and 林柏諭. "Investigation on lipid extraction of microalgae assisted by microwave and ultrasound." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/08194044264048834496.

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Анотація:

碩士
國立臺灣海洋大學
輪機工程系
99
Supersound and microwave were used to assist the lipid extraction of microalgae by solvents in this study. Crude lipid extracted quantity between the supersound and microwave-assisted lipid extraction under various solvents, extracting time and power were compared. The effect of emulsified solvent on the crude lipid extraction ratio was studied as well. The experimental results show that Isochrysis galbana extracted by microwave using the solvent mixture of n-heptane and iso-propanol in 2:1 volumetric ratio had the largest extracted quantity of crude microalgae lipid which is 10.87 wt. %. The extracted quantity of the crude lipid of Isochrysis galbana is the largest, 10.45 wt. % when ultrasound-assisted extraction was used together with iso-propanol solvent. In addition, the Isochysis galbana extracted by microwave using the emulsion of n-hexane and iso-proanol had higher lipid extracted quantity than that using the mixture of the same two solvents, while the extracted lipid by the latter solvent mixture appeared linear increase with the input energy of microwave. The fatty acid compositions of Isochrysis galbana which were transesterified from crude lipid was compared with those directly from the microalgae powder and those of commercial biodiesel from waste cooking-oil. It was found that the fatty acid methyl esters from transesterification of crude microalgae lipid had higher saturated fatty acid, higher oxidative stability, kinematic viscosity and calculated cetane number while lower calculated iodine value than those from the microalgae powder. In contrast, the biodiesel from waste cooking oil had the highest fatty acids of long carbon chain and heating value among IV those three biodiesels.

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32

Almeida, Maria Beatriz Queiroz Azevedo Malheiro de. "Ultrasound-assisted virgin olive oil extraction : developing an innovative plant engineering solution." Master's thesis, 2015. http://hdl.handle.net/10400.14/20132.

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Entre as várias operações envolvidas na produção de azeite virgem, a termobatedura exerce uma influência crucial na qualidade do produto final. É, também, a única operação descontínua do processo em plantas industriais com centrífugas de duas ou três fases, frequentemente realizada por longos períodos, de tempo de modo a obter maiores rendimentos, o que afeta negativamente a qualidade do azeite. A investigação de tecnologias inovadoras e sustentáveis no setor do azeite é crucial para superar limitações inerentes ao processo de extração e satisfazer as exigências do mercado. O ultrassom (US) de alta potência é uma tecnologia já aplicada na indústria alimentar, caracterizada pela rapidez, redução de custos e melhoramento de qualidade. Contudo, a sua aplicação no processo produtivo de azeite virgem é muito recente. Como tal, no presente estudo, pretende-se explorar o potencial da extração de azeite assistida por ultrassom (EAU) na indústria oleícola, abordando o impacto no tempo e rendimento de extração, bem como na qualidade básica, nutricional e sensorial do azeite, no que diz respeito à sua aplicação em diferentes variedades de azeitona, em estágios de maturação diversos. Este estudo representa o primeiro esforço no sentido da implementação da tecnologia de US na produção de azeite em escala piloto, através de um dispositivo ultrassónico projetado especificamente para o efeito. Uma nova abordagem foi seguida, executando a aplicação do US imediatamente após a fase de termobatedura. Azeites virgem mono-varietais foram produzidos a partir de duas variedades típicas Calabresas, Carolea e Ottobratica, do presente ano de colheita, em dois estágios de maturação diversos (fins de outubro e inícios de novembro), numa planta piloto operando a 150 kg/h. A produção de azeite foi realizada em batch, cada um de 50 kg de azeitonas, com uma fase de termobatedura de 30 min nas amostras controlo e de 15 min, seguida de uma fase de sonicação, num total 15 min, nas amostras tratadas. O US foi aplicado com um reator ultrassónico instalado na planta piloto, entre termobatedeira e a centrífuga, com as seguintes características: frequência ultrassónica de 25 kHZ; potência ultrassónica específica de 520 W/L; eficiência calorífica de 80%; potência de saída máxima de 1,0 kW; capacidade produtiva de 10 L/min; capacidade interna de 2,25 L; volume efetivamente sonicado de 1,19L. O fluxo do processo foi de 0,056 L/s e o tempo de residência dentro do reator de 34,2 s. Oito amostras de azeite virgem foram obtidas e testadas em pares controlo-tratado. Os parâmetros básicos de qualidade (acidez, índice de peróxidos, coeficientes de absorção no UV K232 e K270 e análise sensorial) foram estudados. Foi também estudada a eficiência de extração, a composição em ácidos gordos, o conteúdo total em tocoferóis, fenóis e voláteis, e ainda os perfis fenólicos e voláteis. Nas condições experimentais aplicadas, o tratamento de US não afetou os parâmetros básicos de qualidade, observados dentro dos limites legais estabelecidos para o azeite virgem. Azeites tratados revelaram maiores concentrações em ácidos gordos poliinsaturados, bem como, maior conteúdo de compostos minoritários, à exceção dos tocoferóis que sofreram perdas ligeiras. O conteúdo fenólico, nomeadamente lignoides e secoiridoides, e em compostos voláteis C6 (aldeídos e álcoois) e C5 (dímeros penténicos) aumentou significativamente com o tratamento. A qualidade sensorial apresentou melhorias nas notas de frutado, amargo e picante, mais intensas em azeites sonicados. A EAU potenciou a transferência de massa e calor do processo, resultando em maiores rendimentos e reduzindo significativamente o tempo de termobatedura, sem danificar a qualidade do azeite. Os resultados obtidos foram empregues na projeção do upscaling do processo, complementada por uma análise de custos. O processo mostrou ser viável do ponto de vista financeiro, reduzindo o custo de moagem em 3% por unidade (0,75 L) e o custo total de produção em 0,14€ por unidade. Representando um passo em direção à continuidade do processo, este estudo promove a implementação da EAU a nível industrial no setor oleícola, o que se pode afirmar ser um investimento estratégico com benefícios a nível de custo, eficiência de produção, qualidade de produto e sustentabilidade do processo.
Malaxation is one of the most determining process steps for the final quality of virgin olive oil (VOO). It is also the only discontinuous operation in industrial plants working with two or three phases decanters, often requiring long kneading times to maximize process efficiency, which can negatively affect the VOO quality. In order to overcome these drawbacks and fulfill market and consumer exigencies, VOO research and industry have worked towards the development of innovative and sustainable plant engineering solutions. High power ultrasound (HPU) has well proven its potential as a fast, quality-improving and cost-effective technology in the food industry, but it was not until recently that application on the VOO sector was considered. The aim of this study is to further explore the potential ultrasoundassisted extraction (UAE) as a suitable process alternative, shedding light in the technology’s impact on process parameters, such as extraction time and yield, and basic, nutritional and sensorial VOO quality, in relation with olive maturation stage and cultivar. This work represents the first effort to implement ultrasound (US) technology in VOO production at a semi-industrial scale, with an ultrasonic device especially designed for the purpose. Moreover, an innovative approach of US application, performed after the malaxation step, was studied. Mono-varietal virgin olive oils were produced from two cultivars typical of the Calabria region, Carolea and Ottobratica, from the present crop year, at two different ripening stages (end of October and beginning of November), in a low-scale mill plant, with a working capacity of 150 kg/h. Experimental trials were carried out by processing 50 kg batches of olives, performing a 30 min malaxation step, in the control samples and a 15 min malaxation of plus sonication, for a total time of 15 min, in treated samples. HPU application was carried out by sonication of olive pastes after the malaxation step, in a stateof- the-art ultrasonic reactor, integrated in the low-scale plant between the malaxer and the two-phase decanter centrifuge. The reactor’s characteristics were the following: ultrasonic frequency of 25 kHz; specific ultrasonic power of 520 W/L. The process flow rate was 0.056 L/s and the residence time inside the reactor was 34.2 s. Eight VOO samples were obtained and tested in control-treated pairs. Basic quality parameters free acidity, peroxide value, specific extinction coefficients K232 and K270 and sensory analysis were assessed. Moreover, yield efficiency, fatty acid composition, total tocopherol, phenol and volatile content, as well as phenolic and volatile profile, were determined. In the experimental conditions tested, US treatment did not affect VOO quality parameters, which were within the legal limits for virgin edible oils. US treated oils showed greater concentrations of PUFA and a higher content in minor compounds, apart from tocopherols, which slightly decreased. Consistent and significative increases of total phenolic content, namely lignans and sericoridoids, and C6 (aldehydes and alcohols) and C5 (penten dimers) volatile compounds, were verified as a result of US treatment. Oils from sonicated pastes showed improved sensorial quality, with an intensity increase of fruity, bitter and pungent notes. From an engineering standpoint, UAE improved mass and heat transfer efficiency, giving better oil extractability and yields while significantly reducing malaxation time (by half), without compromising VOO quality. The results obtained from experimental trials were employed to suggest an upscaling solution of the UAE process, complemented by a cost-volume-profit financial projection. Industrial UAE showed to be viable from the financial perspective, reducing olive milling associated cost by 3% per unit (0.75 L) and overall VOO cost by 0.14 € per unit. The results of this study represent a step forward in achieving process continuity and may constitute a stepping-stone for UAE widespread industrial implementation in the VOO sector. US implementation in VOO production would thus represent a minor and strategic investment, with a net advantage in operation cost, production efficiency, product quality and process sustainability.

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33

Hung, Ying-Shiu, and 洪英修. "Recovery of PGM's from Spent Autocatalyst Using Hydrometallurgy and Ultrasound-Assisted Solvent Extraction." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/50348799768797260971.

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Анотація:

碩士
國立中山大學
環境工程研究所
89
In this study, various techniques of hydrometallurgy and ultrasound-assisted solvent extraction were used to recover the platinum group metals (PGM’s) from a composite sample of honeycomb-type autocatalysts. After they were removed from the converter casings, the autocatalyst substrates were first crushed and then ground by a ball mill. The recovery procedures employed are shown as follows: (1) dissolve PGM’s from ground spent autocatalyst by aqua regia leaching; (2) separate PGM’s from base metals in the aqua regia leachate by metal cementation using zinc powder so that PGM’s can be precipitated out; (3) the PGM’s precipitate was first dissolved by aqua regia, then proceed to remove nitrate and hydrochloride within. The residue was further dissolved in hydrochloride acid as a preparation step for solvent extraction; (4) the PGM’s pregnant solution of hydrochloride acid was treated by solvent extraction and stripping to separate and purify each component of PGM’s. Effects of ultrasound agitation on the efficiency of solvent extraction was also evaluated in this work. Results of aqua regia leaching experiments have shown that the quantity of dissolved PGM’s increased as the solid-to-liquid ratio decreased. The maximum dissolved quantity of PGM’s could be obtained by a 3-hr leaching time. At this stage, the PGM’s recoveries are 80-90% for platinum and rhodium and greater than 99% for palladium. The result of a preliminary test has indicated that acetic acid can not effectively separate the PGM’s and base metals. Thus, the method of cementation by zinc powder was employed to separate PGM’s from base metals. Before cementation, the aqua regia leachate was diluted and pH-adjusted to greater than 2. In so doing, an almost complete cementation (>99%) could be obtained by the least quantity of zinc powder. In addition, the base metals occurred with the PGM’s precipitate have been minimized except lead and zinc. While palladium was extracted by di-n-octyl sulfide (DOS), ultrasound assistance has rendered a complete extraction within a few minutes. At this stage, the extraction efficiency was found to be independent of the HCl concentration. It was found that platinum and rhodium were not extracted by DOS. When platinum was extracted by tri-n-octylamine (TOA) and assisted by ultrasound, rhodium will be extracted at the HCl concentration higher than 4M. Thus, TOA is not an effective chemical for selective extraction of platinum. TOA was then replaced by tributyl phosphate (TBP). Experimental results have indicated that the extraction of platinum using TBP was affected by the HCl concentration. The best result was obtained when the HCl concentration was 5M. Extraction by TBP was found to be fast. It took only 20-30 seconds to reach the equilibrium even with no ultrasound assistance. But multi-stage extractions are generally required to extract platinum completely. Rhodium was found to be not extracted by TBP. After palladium and platinum were extracted, only rhodium was remained in the reffinate. In summary, solvent extraction using DOS and TBP has made it possible to separate palladium, platinum, and rhodium effectively. In the palladium stripping solution almost no base metals was determined. However, zinc and lead were found in the platinum stripping solution and the rhodium-containing raffinate. These base metals should be removed to achieve a better purity for each precious metal. The TCLP (i.e., a leaching test for toxicity) result of the autocatalyst substrate after aqua regia leaching has found to be non-hazardous. However, several streams of wastewater and acid gas generated in the recovery process should be properly managed to avoid the secondary pollution.

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34

黃秋燕. "The Physicochemical Properties and Antioxidant Activity on Ultrasound-assisted Extraction of Spirulina platensis Extractives." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/30580574335591164149.

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Анотація:

碩士
國立臺灣海洋大學
食品科學系
100
Spirulina platensis contains 64.89±0.38% curde protein. Phycocyanin is one kind of photosynthetic pigment that is widely used in food industry, cosmetic, biochemical dye and also be evidenced the antioxidant capacity. In this study, we used ultrasound-assisted extracted Spirulina platensis in water, evaluating the production rate, phycocyanin content and antioxidant capacity. Observation by microscopy, fragmentation of algae was increased by ultrasonication with ultrasonic power increasing or the ultrasound frequency decreasing. The higher ultrasounic power, was resulting the higher yields, protein content (R = 0.81) and phycocyanin purity (R = 0.69), on the other hand the lower ultrasounic frequency was resulting the higher protein content (R = 0.63), but the lower phycocyanin purity (R = 0.43). Colors of extracts were affected by phycocyanin purity. The b value have the negative correlation with phycocyanin purity (R = -0.95). Absorbance of extract at 500-800 nm was increased as ultrasounic power increasing. Absorbance of extract was increased as ultrasonic frequency decreasing. It may be causing by ingredients were more complex due to fragmentation of proteins. The main protein of extract is phycocyanin detecting by SDS-PAGE. However the numbers of protein bands become more due to protein denatured at 60℃ and 20 kHz. The higher ultrasounic power makes the antioxidant of extract lower capacity; At 20 kHz, the ingredients were complex due to ultrasonics degradation, making DPPH free radical scavenging activity (88.19±2.62%) and reducing power (25.13±1.95 ppm of ascorbic acid) increase. The higher ultrasounic power, lower frequency and treated temperature at 60℃ making iron-chelating ability and superoxide radical scavenging activity lower.

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35

Lin, Wei-Min, and 林偉民. "Optimization of Ultrasound-Assisted Extraction of Chlorogenic Acid from Lonicera japonica by Artificial Neural Network." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2e4w2e.

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Анотація:

碩士
國立中興大學
化學工程學系所
106
Lonicera japonica is a traditional Chinese herbal medicine in East Asia. Flower of buds of L. japonica, called honeysuckle, have been applied to anti-oxidant, anti-bacterial、anti-hypertensive effects and anti-diabetes, etc. Chlorogenic acid (CGA), the ester formed between caffeic acid and quinic acid, is a well-known phenolic compound. The known chlorogenic acid, a primary bioactive compound in flower buds, has more pharmacological activities. Many studies have indicated that chlorogenic acid possesses many benefits for health, such as anti-oxidant, whitening, anti-bacterial, antihypertensive effects, anti-obesity, anti-diabetes, neuroprotective properties and anti-tumor. Thus, chlorogenic acid is considerable potential for future development. To extract the bioactive compound in the plant, the traditional extraction method is conventionally performed by heat-reflux extraction with alcohol as the solvent. However, this method is very time-consuming for heat-reflux extraction. To improve the shortcomings of the traditional extraction method, ultrasonic-assisted extraction has been applied to extract the active ingredients of plants in recent years. The ultrasound could create cavitation in the liquid solution to increase the efficiency of extraction as well as reduce extraction time and solvent consumption. This study used ultrasonic-assisted extraction and ethanol as a solvent for extraction. The extraction efficiencies of the ultrasonic-assisted extraction and the shaking bath extraction system were compared. The experimental results showed that the ultrasonic-assisted extraction reached its maximum value after 10 minutes of extraction, followed by a steady state for extraction. However, the extraction by shaking bath for 60 minutes had not yet reached a maximum yield, which was inferior to ultrasound-assisted extraction. Using the mass transfer coefficient (KT) for comparison, the calculation results showed that the ultrasonic-assisted extraction method was better than the shaking extraction method. Moreover, we investigated parameter effects on extraction. The parameters are respectively temperature (X1: 30–70°C), ethanol concentration (X2: 55–95%), liquid to solid ratio (X3: 10:1–50:1 mL/g) and ultrasonic power (X4: 90–150W). This study was designed to optimize the ultrasound-assisted extraction of chlorogenic acid of Lonicera japonica using a response surface methodology (RSM) and central composite design (CCD; five-level-four-factors). According to the RSM, we found out the optimum extraction conditions and predicted extraction yield. Additionally, artificial neural network (ANN) is further performed to predict, analyze and compare with the predicted results of RSM. By analysis of variance (ANOVA), the R2 of RSM and ANN were 0.7913 and 0.9898, respectively, and the RMSE, MAD, and MAPE of ANN were better than RSM. The optimal conditions of extraction process were as follows: temperature of 33.56°C, ethanol concentration of 65.88%, liquid to solid ratio of 46:1 mL/g and ultrasonic power of 150W. The RSM showed that the predicted yield was 45.63 mg/g. The ANN showed that the predicted yield was 44.78 mg/g. The actual experimental value was 43.13±1.44 mg/g. Overall, the above experimental results show that ANN has higher prediction accuracy than RSM.

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36

Syu, Da-Hai, and 徐大海. "Ultrasound-assisted Homogenous Dispersive Solid-phase Extraction and GC-ECD for the Determination of Pesticides in Chrysanthemum." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/15515860036724797285.

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Анотація:

碩士
中臺科技大學
食品科技研究所
102
The purpose of this study is to detect Chlorpyrifos、Procymidone、Bifenthrin and Prochloraz in Chrysanthemum by developing the technique of sample pretreatment, ultrasound-assisted homogenous dispersive solid-phase extraction and GC-ECD. For convenience in quantifying the collected solvent, this study utilizes a special designed glass container in the extraction process. The optimum parameters for ultrasound-assisted homogenous dispelrsive solid-phase extraction of Chlorpyrifos、Procymidone、Bifenthrin and Prochloraz were investigated. The best results of extraction process were obtained as follows : 10 mL liquid sample adjusted to pH 3, added 1 mL Acetonitrile as the dispersive solvent and added C18 sorbent, moved to the glass container and added 30 μL Toluene as the extraction solvent, followed by ultrasound-assisted and centrifuged to phase separation, the upper layer containing the extraction solvent was injected into GC. Under optimum conditions, the linear ranges were 1 – 500 ng/mL, the R2 randes 0.9974 – 0.9998, the detection limits ranges 0.3 – 0.8 ng/mL, and concentration ratio 190 – 277. The recovery of real sample (Chrysanthemum) were 89.6 – 96.6%. The proposed method can use only very little organic solvent, and its extraction time is more fast comparing traditional methods. Thus it is a green analysis technology.

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37

Albiston, Carly. "Optimisation of ultrasound-assisted extraction of polyphenols and saponins from different parts of the Aesculus hippocastanum seed." Master's thesis, 2021. http://hdl.handle.net/10198/23896.

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Horse chestnut (Aesculus hippocastanum L.) is a deciduous tree cultivated as an ornamental in urban areas with temperate climate across the Northern hemisphere. Among the scientific community, this species is known for the steroidal glycosides, among which aescin is the main active component and is responsible for most of its medicinal properties. Other bioactive compounds such as quercetin and kaempferol glycosides can also be found in this species. Therefore, this study aimed to characterize the phenolic and saponin profiles of the kernel, coat, and husk of the horse chestnut seed, and to optimise the ultrasound-assisted extraction (UAE) of these valuable compounds from the target seed samples using the response surface methodology (RSM). The polyphenol and saponin profiles of the samples were initially characterised by high-performance liquid chromatography coupled with mass spectrometry (HPLC-DAD-ESI/MS). The highest yields of solids (extract weight) were obtained from the kernel and husk of the horse chestnut seed. The kernel mostly contained flavonoids and the coat mostly contained flavan-3-ols, while both classes of polyphenols were found in the husk in comparable amounts. Saponins were also prominent in the kernel of the seed. A five-level central composite rotatable design (CCRD) combining the effects of the independent variables (time, ultrasonic power, and ethanol concentration) was implemented to optimise the UAE of the groups of phytochemicals identified in each sample. The polynomial models were fitted to the experimental data, statistically validated, and used to determine the optimal UAE conditions. Extraction of the target compounds was greatly affected by the three independent variables through linear, quadratic and/or interactive effects. The global optimal processing conditions for the extraction of phenolic compounds and saponins from the kernel, were somewhat similar, with exception to the solvent concentration. On the other hand, the extraction of phenolic compounds from the kernel required a longer processing time and higher ultrasonic power, which can be related to the intrinsic nature of the plant material. The results of this study could be exploited by companies interested in phenolic- and saponin-rich natural ingredients, such as the pharmaceutical, cosmetic, and food industries.
v RESUMO O castanheiro da Índia (Aesculus hippocastanum L.) é uma árvore caducifólia cultivada como ornamental em áreas urbanas de clima temperado no hemisfério norte. Entre a comunidade científica, esta espécie é conhecida pelos glicósidos esteroidais, entre os quais a aescina é o principal componente ativo e responsável por grande parte das suas propriedades medicinais. Outros compostos bioativos, incluindo glicósidos de quercetina e kaempferol, também são encontrados nesta espécie. Portanto, este estudo teve como objetivo caracterizar o perfil em polifenóis e saponinas do miolo, da pele e da casca da castanha da Índia e otimizar a extração assistida por ultrassom (UAE) destes compostos de elevado valor utilizando a metodologia de superfície de resposta (RSM). Os perfis em polifenóis e saponinas das três amostras foram inicialmente caracterizados por cromatografia líquida de alta eficiência e espectrometria de massa (HPLC-DAD-ESI/MS). Os maiores rendimentos de sólidos (massa de extrato) foram obtidos a partir do miolo e da casca da semente da castanha da Índia. O miolo apresentou principalmente flavonoides e a pele flavan-3-óis, enquanto ambos as classes de polifenóis foram detetadas na casca em quantidades comparáveis. As saponinas foram proeminentes no miolo da semente. De seguida, foi implementado um desenho rotativo de composto central de cinco níveis combinando os efeitos das variáveis independentes, tempo, potência ultrassónica e concentração de etanol, visando a otimização da UAE dos diferentes grupos de fitoquímicos identificados em cada amostra. Os modelos polinomiais foram ajustados aos dados experimentais, validados estatisticamente e usados para determinar as condições ótimas de UAE. A extração dos compostos alvo foi bastante afetada pelas três variáveis independentes por meio de efeitos lineares, quadráticos e/ou interativos. As condições ótimas globais de processamento para a extração de compostos fenólicos e saponinas a partir do miolo foram de alguma forma semelhantes, com exceção para a concentração de solvente. Por outro lado, a extração de compostos fenólicos a partir do miolo exigiu um tempo de processamento mais longo e uma maior potência, o que pode estar relacionado com a natureza intrínseca do material vegetal. Os resultados deste estudo poderão ser explorados por empresas interessadas em ingredientes naturais ricos em polifenóis e saponinas, como as indústrias farmacêutica, cosmética e alimentar.

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38

LU, ZHONG-WEN, and 呂仲雯. "Optimization of microwave and ultrasound assisted extraction of ergothioneine from Pleurotus citrinopileatus and their antioxidant activities and purification." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/97r2rd.

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Анотація:

碩士
東海大學
食品科學系
107
Microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) are new extraction technology that has been widely used in food chemistry and medicine in recent years. Compared to conventional extraction, MAE and UAE have many advantages, such as less solvent consumption, shorter extraction time and higher extraction rate. Ergothioneine is a sulfur-containing amino acid that has antioxidant, anti-inflammatory and anti-hyperlipidemic effects; it is present throughout the plant and animal tissues, cannot be synthesized by humans and only available from dietary sources. Since some researchers discovered higher content of ergothioneine in Pleurotus citrinopileatus; this study is about using microwave and ultrasound-assisted extraction of ergothioneine by one-factor-at-a-time and response surface methodology (RSM) to investigate the optimum extraction conditions and purified of ergothioneine. In addition, test the antioxidant capacity by using ergothioneine standard and microwave, ultrasound assisted extraction and hot water extract. The result in one-factor-at-a-time showed that microwave-assisted optimum extraction conditions of ergothioneine microwave power was 500 W, extraction time was 30 min and solid to liquid was 1:30; ultrasound-assisted optimum extraction conditions of ergothioneine extraction time was 40 min, ultrasound power was 75 W and solid to liquid was 1:30. Another result in RSM was focus on the main active components of Pleurotus citrinopileatus, which was ergothioneine, the optimum extraction conditions of MAE microwave power was 552 W, extraction time was 29 min and solid to liquid was 1:31; UAE extraction time was 47 min, ultrasound power was 74 W and solid to liquid was 1:20, which the predict value and the experimental value (n=4) respectively were 1.92 mg/g dw, 1.92 mg/g dw and 1.53 mg/g dw, 1.50 mg/g dw, no significant differences, the ergothioneine equation was valid. From these results, it was found that the MAE of ergothioneine extraction was superior to UAE. On the antioxidant acticity of microwave-assisted extraction extracts from Pleurotus citrinopileatus fruiting body powder (MEP), ultrasound-assisted extraction extracts from Pleurotus citrinopileatus fruiting body powder (UEP) and hot extracts from Pleurotus citrinopileatus fruiting body powder (HWEP). As the concentration was 5 mg/mL, the scavengling ability of DPPH radicals were 82.43, 83.93 and 81.39%; the chelating ability on ferrous ions were 82.80, 72.47 and 72.26%; the reducing power were 0.57, 0.56 and 0.41, and the scavenging ability on ABTS+ radicals were 71.16, 86.66 and 84.66%. According to EC50 value, MEP has good antioxidant properties on scavegling DPPH radicals and reducing power ability; UEP was more efficient than MEP and HWEP on scavenging ability of ABTS+ radicals. Moreover, the chelating ability on ferrous ions, HWEP was the best. MEP, which had most ergothioneine content, was further separated successively by tangential flow filtration (TFF) and IntersilTM Diol column to obtain higher purify ergothioneine. The purity of ergothioneine in MEP was 24.48%, after tangential flow filtration, the purity was 29.03%. In IntersilTM Diol column step, the purify of ergothioneine was 83.25%, recovery was 65.72%. The results show that using LTQ Orbitrap/MS examination purified compound in MEP is ergothioneine. In conclusion, high content of ergothioneine can obtained by MAE of Pleurotus citrinopileatus dried fruiting body powder. Next, with TFF and IntersilTM Diol column, we can get high purity ergothioneine purified product. Therefore, the new extraction technology can not only reduce time but also can prepare functional purified substances with high purity, which used for the development and application of functional components of mushrooms in the future.

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39

Hsu, Jin-Feng, and 許進豐. "Studies on the physicochemical properties of mucilage from the seed of Citrus grandis Osbeck with ultrasound and enzymatic assisted extraction." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/33125007178716762677.

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Анотація:

碩士
國立中興大學
食品暨應用生物科技學系所
105
Citrus grandis Osbeck is Rutaceae, an important cash crop for Taiwan and whose seeds are processed waste. In the related research found that it is rich in mucilage. The extraction method used in the industry is based on the application of acids (pH 1.5–3.0) & high temperature (70–100 °C) and this extraction method is prone to pollution and high economic costs. In recent years, the pursuit of high economy, low pollution, safety of environment-friendly (green) extraction technologies, including ultrasonic and enzyme treatment is considered to have the potential of environment-friendly (green) extraction technologies. Therefore, in this experiment, the effect of ultrasonic extraction factor (ultrasonic temperature, amplitude and time) on the yield of Citrus grandis Osbeck seed was discussed by response surface methodology. It was found that the yield of polysaccharide increased and then decreased with the increase of ultrasonic temperature and amplitude. And the yield of polysaccharide increases with the ultrasonic extraction time and then gradually slow down. The optimum conditions for maximum polysaccharide yield were as follows: extraction temperature 53℃, ultrasonic amplitude 84%, ultrasonic extraction time 40 min. Under the actual optimum extraction parameters, the polysaccharide yield was 4.86 (± 0.22%), which was closely agreed to the predicted yield 4.86%. Electron microscopy can be observed by the outer hull of Citrus grandis Osbeck seed by ultrasonic treatment has obvious damage effect. The physicochemical properties of the polysaccharides were analyzed by water bath extraction, optimized ultrasonic extraction, enzyme extraction and ultrasonic assisted enzyme extraction. In the yield of polysaccharides, the yield of polysaccharides (5.21 ~ 8.61%) was significantly improved by enzyme extraction, and the yield of polysaccharides increased by ultrasonic assisted enzyme extraction. However, in the monosaccharide composition by enzyme extraction, the content of uronic acid was decreased and the content of neutral sugar was increased, indicating that the purity of polysaccharide decreased. FT-IR spectrum of the polysaccharide extracted from the seed of Citrus grandis Osbeck implied that the polysaccharides are all high degree of esterification polysaccharide (DE> 50%). In the molecular weight and intrinsic viscosity, the polysaccharides under ultrasonic treatment were degraded by ultrasonic, so that the molecular weight and intrinsic viscosity were significantly decreased. And in the process of enzyme extraction may produce rich in branched-chain polysaccharides, making the intrinsic viscosity decreased but have a higher molecular weight. The mild condition of the water bath extraction polysaccharide has a higher molecular weight and intrinsic viscosity, and its dynamic viscoelasticity is found to start gel at a concentration of 1%.

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40

Liu, Ching-Wen, and 劉景文. "Optimization of Ultrasound-Assisted Extraction Conditions for Extracts with Blood Glucose Regulation from Psidium guajava Leaves and the Regulatory Mechanisms on Blood Sugar." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/6sqvnt.

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Анотація:

博士
東海大學
畜產與生物科技學系
104
In this study, we established the optimum ultrasound extraction conditions for maximizing total phenols yield and maximum inhibition of the two starch-digesting enzymes α-amylase and α-glucosidase from guava leaves. The response surface methodology (RSM) was employed for empirical model building. The effects and mechanisms of aqueous guava leaf extract (GvEx) on insulin resistance were evaluated in high glucose-induced insulin-resistant mouse FL83B cells and high-fructose-highfat fed mice. Results showed the second-order polynomial models suitably described the experimental data. Extraction temperature, time, and v/w ratio showed the significant quadratic effects on total phenols and inhibition of α-amylase and α-glucosidase. The 26.12% mean value of total phenolic content, 47.23% inhibition of α-amylase activity and 59.42% inhibition of α-glucosidase activity were obtained at their optimal extraction conditions, respectively. In addition, extracts of guava leaf had the better anti-hyperglycemic activity than commonly used diabetic drug acarbose. The aqueous extract of guava leaves contained 0.87% gallic acid, 0.62% chlorogenic acid, 0.11% caffeic acid, 2.25% catechin, 1.45% epicatechin, 0.47% epigallocatechin gallate, and 0.83% quercetin. Results from the study of FL83B cells showed that administration of 200 and 400 μg/mL GvEx resulted in a significant increase in glucose uptake and intracellular glycogen content (p < 0.05). Further, western blot analysis revealed that 200 and 400 μg/mL GvEx significantly enhanced the levels of insulin-related signaling components, including insulin receptor (IR), as well as enhancing the phosphorylation of the insulin receptor (p-IR (Tyr)), insulin receptor substrate (p-IRS (Tyr)), p85 regulatory subunit of phospho-inositide 3 kinase (PI3K (p85)), protein kinase B (p-Akt (Ser)), glucose transporter 2 (Glut 2), and glycogen synthase. These results demonstrated that GvEx improved insulin resistance by promoting glucose uptake and enhancing glycogen content via modulation of the insulin signaling pathway in high glucose–induced insulin-resistant mouse FL83B cells. In vivo results showed that administration of GvEx significantly enhanced the glucose tolerance, insulin sensitivity and increased the serum adiponectin content. Triglyceride and total cholesterol content both in blood and liver were significantly decreased after treatment with GvEx. Further, western blot analysis revealed that GvEx can improve the disturbed glucose and lipid metabolism by regulating the related signal transduction pathway in high-fructose high-fat fed insulin-resistant C57BL/6J mice.

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41

Chiang, Chia-Fang, and 江佳芳. "Effect of enzyme-assisted extraction in combination of ultrasound treatment on the physicochemical properties of mucilage from the fronds of Asplenium australasicum （J. Sm.） Hook." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z956uc.

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Анотація:

碩士
國立中興大學
食品暨應用生物科技學系所
106
Enzyme-assisted extraction (EAE) possess the advantages of being environmentally friendly and easily operated owing to relatively mild reaction conditions while ultrasound-assisted extraction (UAE) owns high frequency and strong penetration that both of EAE and UAE are considered to be the innovative and green extraction technology. Therefore, in this study, mucilage from Aspenlenium australasicum was first extracted by xylanase, glucanase and a combination of these two enzymes, followed by ultrasound treatment. The effects of enzyme and ultrasound treatment on the physicochemical properties of the mucilage were investigated including basic composition, monosaccharide composition, polysaccharide functional groups, molecular weight distribution, intrinsic viscosity, rheological properties, water and oil holding capacity, and glucose dialysis retardation index. It was observed that compared to the control, the yield of mucilage increased significantly by EAE and UAE (from 3.64% to 6.04~7.47%). SEM results showed that enzymes can erode the raw material which contributed to the higher yield of mucilage, especially in assisted with ultrasound. The FT-IR fingerprint did not change pronouncedly due to the action of the enzymes and ultrasound, which meant they wouldn’t destroy polysaccharide structure. In monosaccharide composition, the ratio of uronic acid to neutral sugar is about 3:17, which galacturonic acid is approximately 4~5 times that of glucuronic acid while galactose, glucose and fucose were primary neutral sugar. Compared with the control group, the content of galacturonic acid and glucose increased significantly after EAE. It could be the change of monosaccharide composition and the complexity of polysaccharide branching that significantly reduced the intrinsic viscosity and the glucose dialysis retardation index of the mucilage. EAE mucilage possessed higher molecular weight, but after UAE, the polysaccharide branches were degraded by ultrasound, which in turn reduced the molecular weight and increased the intrinsic viscosity. Further studies on rheological properties found that in steady shear test, mucilage from Aspenlenium australasicum was non-Newtonian fluid with shear thinning property while frequency sweep showed that G’ and G” increased with increasing concentration, and G’ was higher than G” (gel-like) in the concentration of 6%. However, both G’ and G” decreased after UAE, indicating that ultrasound treatment would reduce gelling capacity of the mucilage. The water holding capacity of the EAE mucilage was slightly lower than the control but increased after UAE, while there was no significant difference in oil holding capacity. As compared to other dietary fibers, the mucilage from Aspenlenium australasicum still showed good water and oil holding capacity.

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42

WANG, WEN-HUEI, and 王文慧. "Effect of Ultrasound-Assisted Extraction on the Functional Property and Flow Behavior of Chia Seed (Salvia hispanica L.) Mucilage and Its Interaction with Different Proteins." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/m885a4.

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Анотація:

碩士
輔仁大學
食品科學系碩士班
107
The soluble fiber on the seed coat of chia seed (Salvia hispanica L.) possesses the viscosity and water holding capacity. However, these fibers are not easily separated from the seed coat. Thus, they have not been applied to the food industry. Ultrasonication can improve the mass transfer efficiency and shorten the extraction time. It is also an environmentally friendly processing. In addition, polysaccharide and protein are often used as functional ingredients in foods. The interaction between them often affects macro property of food, such as stability and texture. Therefore, the objective of this study is to investigate the effect of ultrasound-assisted extraction on the functional property and flow behavior of chia seed mucilage and its interaction with different proteins. Chia seeds were mixed with distilled water and the pH of solution was adjusted to 9. The solution was then treated with water bath extraction (WBE) and probe-type sonication (PTS) at 50°C and 80°C for 30 and 60 min. The mucilage of chia seed was obtained after separating the residues. In addition, the proteinease was added to the solution to hydrolyze the protein in mucilage, and the 95% ethanol was used to precipitate the purified mucilage. Finally, the mucilages were freeze-dried to obtain the powder. The yield, appearance, color, composition, functional properties and rheological properties of the mucilage powders were performed. The binary mixture phase diagrams of mucilage and different proteins (soybean protein isolate, whey protein isolate and sodium caseinate) were constructed. The results showed that the yields of mucilage treated with WBE and PTS were 1.03-1.86% and 6.92-10.52%, respectively. The above results indicated that the PTS could assist the separation of mucilage layer from chia seed and consequently increase the yield. The carbohydrate content of the mucilage treated with PTS was in the range of 73.84-83.45%. The carbohydrate content of the mucilage treated with PTS at 50°C for 30 min was the highest. The carbohydrate content of the purified mucilage was 90.38%. The mucilage treated with PTS at 50°C had better functional properties. Furthermore, both chia seed mucilage and xanthan gum solution belonged to the Non-newtonian shear thinning fluid with the yield stress, which was consistent with the Herschel-Bulkley fluid model. The 1% chia seed mucilage treated with PTS at 50°C for 30 min had a lower flow behavior index (0.662), indicating a high degree of shear thinning. It also had a higher yield stress (385.0 mPa), consistency index (226.0 mPa.sn), and apparent viscosity. The flow behavior index (0.355) of purified chia seed mucilage was lower and the yield stress (1685 mPa), consistency index (1684 mPa.sn), and apparent viscosity were higher than the unpurified one. The results of the phase diagram showed that the compatibility between chia seed mucilage and whey protein isolate was the highest as compared to soy protein isolate and sodium caseinate. In conclusion, ultrasonication could assist the separation of mucilage layer from chia seed. Chia seed mucilage has potential for application in the food industry.

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43

Mossop, Nicholas Paul. "Bioactive extracts of Olea europaea waste streams : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology in Food Technology at Massey University." 2006. http://hdl.handle.net/10179/789.

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The production of olive oil has seen an increase in recent years due to a broader understanding of the health benefits of the Mediterranean Aliment Culture. With this expanding industry we also see an increase in the waste products associated with olive oil production. Given the high polluting content of the waste streams and the economic costs associated with its removal and processing, waste remediation and disposal has become a significant point of interest for both producers and local bodies. In this project, wastes of the olive oil production industry are examined for their use as the raw material for a novel product used in the control of horticulturally important diseases, examining the effect of extraction protocols on the activity of the final product. Active fractions of the olive oil wastes were identified from literature and protocols for their extraction and recovery developed; incorporating both standard solvent extraction and novel ultrasound-assisted extraction. Criteria for the analysis of extract quality were outlined and potential target applications identified. The biophenolic compounds of olive wastes were identified as providing the majority of the active fraction, so protocols were developed for the recovery of these compounds. Standard solvent extraction and ultrasound-assisted extraction were examined for their effectiveness of biophenolic recovery and their effect on product quality. Certain horticulturally important diseases were identified as potential targets, and bioassays undertaken to determine the ability of a crude extract to inhibit and control these diseases. It was found that the action of ultrasound during extraction provides a greater degree of recovery of biophenolic compounds, with minimal loss of product quality; as determined by bioassays and total biophenol determination. This increase in recovery is due primarily to the destruction of cellular material resulting in higher rates and absolute yields of recovery. This work provides evidence of the occurrence of some interesting phenomenon in the recovery of biophenols from olive wastes that deserves further examination. The crude olive leaf extract was shown to have an inhibitory effect on bacteria and effectively no inhibitory effect on fungal species in the total biophenol ranges tested. Erwinia amylovora and Staphylococcus aureus both showed a large susceptibility to the olive leaf extract. Results showed a higher degree of susceptibility of Gram positive bacteria and a potential resistance in soil microbes. For bacterial species, total biophenol concentrations of 0.15 to 3.50 mg GAE/ml provided inhibitory effects, while with the fungal species tested, no inhibitory effects were found at total biophenol concentrations of up to 2.50 mg GAE/ml. Some evidence exists that there is an opportunity for the economic recovery of olive biophenols for use as a novel product, but more work is required to determine specific applications and/or targets of use, as well as optimisation of the extraction and purification protocol. A sample removed from interfering compounds will allow the examination of activity of particular compounds and hence a better understanding of the action of the olive waste extract.

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44

Brás, Teresa Isabel de Amoreira Sousa e. Silva. "Production of cynaropicrin extracts from Cynara cardunculus leaves and its use for development of wound dressing films." Doctoral thesis, 2020. http://hdl.handle.net/10362/111454.

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Natural compounds derived from plants are presently an alternative for the discovery of new effective drugs, from which new products may be developed, potentially overcoming the current limitations of synthetic compounds for use in pharma and biomedical applications. This thesis concerns the design and production of cynaropicrin enriched extracts from leaves of Cynara cardunculus, and their application in a chitosan matrix as wound dressing for antiinflammatory drug delivery. The design and production of cynaropicrin enriched extracts was performed considering the use of environmentally friendly extraction methodologies and biocompatible solvents. Selection of solvent and the extraction methodology took into consideration their effect upon cynaropicrin extraction yield, as well as energy expenditure and other operating costs. Among conventional and nonconventional extraction methodologies, ultrasound assisted extraction combined with ethanol presented the best results regarding the cynaropicrin extraction yield (55.00 mg/g Dry Weight) and energy expenditure (0.027 kWh/gcynaropicrin). Applied for the first time for cynaropicrin extraction from C. cardunculus leaves, ultrasound assisted extraction was firstly optimized regarding the pulse effect on cynaropicrin extraction yield. Comparatively to continuous mode, pulse mode (duty cycle of 25%) presented a reduction on energy consumption/gcynaropicrin, as well as a better temperature control being selected and further optimized with a response surface methodology, using the Box-Behnken design model. The results obtained confirm the applicability of the response surface methodology for optimization of cynaropicrin extraction by pulsed ultrasound assisted extraction, from C. cardunculus. Aiming the increase of the extract biological potential, fractionation of the optimized extract was performed by membrane processes. A Duramem® 200 membrane was selected for the retention of cynaropicrin while low molecular weight compounds, such as glucose and fructose, were removed by diananofiltration (after 5 diavolumes). As a result of the diananofiltration process, a global removal of 93.0% of glucose and 95.6% of fructose was obtained. An increase of the extract biological potential was achieved, when tested with a Bj5-ta human normal fibroblast cell line. The integrated process for production of cynaropicrin enriched extracts was economically assessed, leading to a pay-back period of 4.58 years, achieved for a production of 520 kg/ of extract. Incorporation of the cynaropicrin enriched extract in chitosan films, was performed by the solvent evaporation method, with different concentrations of the extract. It was shown that the extract has a negative effect on the film tensile strength and on the fluid absorption capacity being these two effects strongly influenced by the amount of extract loaded in the chitosan films. With no cytotoxic effect on Bj5-ta cell line observed, for films with an extract concentration lower to 5%, a positive effect on skin inflammation was achieved. An 86% reduction on IL-6 cytokine levels production after exposure to chitosan with 5% extract, by indirect contact, was obtained being this effect positively correlated to the cynaropicrin content in the extract loaded into the chitosan films. xii This work shows that cynaropicrin enriched extracts from C. cardunculus leaves, can be produced in a sustainable and environmentally friendly way, aiming the possibility to be scaled up for industrial applications. Besides that, its potential use as chronic skin wound dressing, allied to chitosan, is a promising approach overcoming the application of synthetic drugs, and/or potentiate their application spectrum on what regards to anti-inflammatory action.

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Martins, Pedro Miguel Mota. "Carotenoid-based solutions for the replacement of artificial colorants in pastry products." Master's thesis, 2020. http://hdl.handle.net/10198/24712.

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Colour has a great importance in the first consumers’ impression, allowing to infer about the overall quality, the taste, the smell, the texture, and even the safety of foodstuff. For these reasons, there is a massive use of colorants in food products. Among the numerous natural matrices potentially used for the extraction of colouring compounds, the fruits from the genus Solanum represent promising sources of pigments, namely carotenoids. This reason, together with the fact that large amounts of fresh tomato wastes (resulting from crop growing, packaging, processing, storage, and sale) are discarded worldwide, make the recovery of valuable colorant biomolecules from agri-food wastes a crucial step of the circular economy by re-introducing them into the food chain as ingredients. In the present work, ultrasound-assisted methodologies were applied to obtain carotenoid-rich colouring extracts from three varieties of tomato (traditional red tomato - Solanum lycopersicum L., cherry tomato – S. lycopersicum var. cerasiforme, and yellow pear tomato – S. lycopersum 'Beam's Yellow Pear), using green solvents, and HLPC-DAD-ESI/MS to establish the carotenoid profile of each sample. Furthermore, the most promising and bioactive extracts were applied in a commercialized pastry cream to substitute the currently used artificial colorants, and finally an in-depth nutritional, chemical, and bioactive characterization of the obtained products was performed, complemented with their physical attributes, studied at Time 0 and 3 days of storage. Lycopene and β-carotene were the major carotenoids found in tomato extracts. None of the studied samples showed hepatotoxicity (including the artificial colorant), and cherry tomato extract was the one with the highest antioxidant and antimicrobial activity. All the creams coloured with the three tomato extracts revealed a uniform aspect and were stable in terms of structure and colour after the heat resistance test. The colour of the creams revealed no significant change over time; however, the pH levels suffered a growing tendency, except for the cream coloured with yellow pear tomato extract, which presented the most stable pH levels. As expected, the cream with the artificial colorant showed the best texture attributes, since the high quantity of carotenoid-rich extracts needed to achieved the final color lead to a weaker texture. Nevertheless, the cream coloured with cherry tomato extract presented the strongest cohesiveness and work of cohesion, while cream with yellow pear tomato presented the best firmness and consistency.Cherry tomato coloured cream presented the highest amounts of protein, fat, and ash, as also higher energetic value. Three soluble sugars were found, fructose, glucose, and trehalose; and citric acid was the major organic acid detected. Saturated fatty acids were found in the highest percentages in all samples, mainly due to the presence of palmitic acid, being oleic acid the second most abundant fatty acid. Finally, all creams revealed antioxidant properties, similar to the respective extracts, and no toxicity was observed for the VERO cell line. A significant improvement in the antimicrobial activity of the creams was verified, comparing with the extract, especially in the cream coloured with cherry tomato extract. The colouring capacity of these molecules makes them a very attractive target for the industrial sector, since carotenoid-based colorants appear as a valid solution for application in the pastry sector, that greatly relies on yellow/orange artificial colorants.
A cor tem uma grande importância na primeira impressão do consumidor, permitindo-lhes inferior sobre a qualidade geral, o sabor, o cheiro e até mesmo sobre a segurança do alimento. Por estas razões, os corantes são massivamente utilizados em produtos alimentares. Entre as inúmeras matrizes naturais potencialmente utilizadas para a extração de compostos corantes, os frutos do género Solanum representam fontes promissoras de pigmentos como os carotenoides. Esta razão, juntamente com o facto de que grandes quantidades de resíduos de tomate fresco (resultantes da produção, embalamento, processamento, armazenamento e venda) são descartadas em todo o mundo, tornam a recuperação de biomoléculas corantes de alto valor acrescentado a partir de resíduos agroalimentares, uma etapa crucial da economia circular através da sua reintrodução na cadeia alimentar como ingredientes. Neste trabalho, foram aplicadas metodologias de extração assistidas por ultrassons para obter extratos corantes ricos em carotenoides a partir de três variedades de tomate (tomate vermelho tradicional - Solanum lycopersicum L., tomate cereja – S. lycopersicum var. Cerasiforme e tomate pêra amarelo – S. Lycopersum 'Beam's Yellow Pear), usando solventes verdes, e HLPC-DAD-ESI/MS para estabelecer o perfil de carotenoides de cada amostra. Posteriormente, os extratos mais promissores e bioativos foram aplicados num creme de pasteleiro comercial de forma a substituir os corantes artificias atualmente usados. Finalmente, foi efetuado um estudo profundo de caracterização nutricional, química e bioativa, bem como dos parâmetros físicos dos cremes, avaliados no tempo 0 e após 3 dias de armazenamento. O licopeno e o β-caroteno foram os principais carotenoides detetados nos extratos de tomate. Nenhuma das amostras estudadas apresentou hepatotoxicidade (incluindo o corante artificial), sendo o extrato de tomate cereja o que apresentou maior atividade antioxidante e antimicrobiana. Todos os cremes corados com os três extratos de tomate revelaram um aspeto uniforme e estabilidade em termos de estrutura e de cor após o teste de resistência ao calor. A cor dos cremes não revelou nenhuma alteração significativa ao longo do tempo; no entanto, os níveis de pH sofreram tendência crescente, exceto para o creme corado com extrato de tomate pêra amarelo, que apresentou os níveis de pH mais estáveis. Como esperado, o creme preparado com o corante artificial apresentou os melhores atributos de textura, uma vez que a grande quantidade de extrato, rico em carotenoides, necessário para atingir a cor final provoca alterações na textura. No entanto, o creme corado com extrato de tomate cereja apresentou maior coesividade e trabalho de coesão, enquanto o creme com tomate pêra amarelo apresentou melhor firmeza e consistência. O creme com extrato de tomate cereja apresentou os teores mais elevados de proteína, gordura e cinzas, além de um valor energético superior. Três açúcares solúveis foram encontrados, frutose, glicose e trealose; e o ácido cítrico foi o principal ácido orgânico detetado. Os ácidos gordos saturados foram os mais abundantes em todas as amostras, principalmente devido à presença do ácido palmítico, sendo o ácido oleico o segundo ácido gordo mais abundante. Por fim, todos os cremes revelaram propriedades antioxidantes semelhantes aos respetivos extratos, não sendo observada toxicidade para a linha celular VERO. Verificou-se uma melhoria significativa na atividade antimicrobiana dos cremes, em comparação com o extrato, principalmente no creme corado com extrato de tomate cereja. A capacidade corante destas moléculas torna-as um alvo muito atrativo para o setor industrial, surgindo os corantes à base de carotenoides como uma solução válida para aplicação no setor da pastelaria, que depende muito dos corantes artificiais amarelo/laranja.
This work has been financed by the FEDER-Interreg España-Portugal programme for financial support through the project TRANSCoLAB 0612_TRANS_CO_LAB_2_P; to the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte-01-0247-FEDER- 024479: ValorNatural®.

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Detti, Cassandra. "New insights on the diversity of phytocomplexes from Mediterranean shrubs species and their potential nutraceutical and industrial applications." Doctoral thesis, 2022. https://hdl.handle.net/2158/1279479.

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Mediterranean plants are exposed to different environmental stresses, such as high temperatures, solar irradiance, and low water availability, that coexist together, especially during the summer period. To cope with such a combination of stresses, these plants have developed a suite of morpho-anatomical, physiological, and biochemical mechanisms. In particular, they increase the production of secondary metabolites with many defensive functions. Among them, polyphenolic compounds play an important ecological role, acting as UV screeners and antioxidants against reactive oxygen species (ROS) which are produced when the photosynthetic metabolism is impaired by abiotic constraints. The aim of this PhD project was to investigate four native Mediterranean wild species (Arbutus unedo L., Cistus x incanus L., Myrtus communis L. and Pistacia lentiscus L.) as sources of phytocomplexes that can be exploited for nutraceutical and other industrial applications. We have planned the set-up of green extractive methods to obtain polyphenolic rich extracts from their leaves and fruits, to perform a field-experiment for enhancing the polyphenolic production, and to test the potential utilization of these phytocomplexes as nutraceuticals. To achieve this, the initial part of the project was the setting up of efficient ultrasound-assisted (UAE) extractions using the Response Surface Methodology. In particular, a fractional factorial screening was performed to verify the effects of different levels of temperature, solvent volume, percentage of ethanol and time followed by an optimization step using a Box-Behnken design. Then, a field-experiment for enhancing the leaf polyphenolic and arbutin yield in A. unedo plants was performed through the application of water stress on a seasonal basis. Finally, the potential utilization of A. unedo and M. communis as nutraceuticals sources was also tested through the inclusion of their polyphenolic fruit extracts into whey milk, a dairy waste product. Regarding the optimization of the extractions, for P. lentiscus, higher content of total polyphenols can be achieved extracting the leaves using 50% of ethanol at 50 °C for 15 minutes with a solvent ratio of 0.13 L g-1. For A. unedo, a higher amount of arbutin was obtained using 75% of ethanol at ambient temperature for 15 minutes with a solvent ratio of 0.06 L g-1. Finally, for C. incanus the highest content of polyphenols was obtained using 60% EtOH at 40 °C for 60 minutes using 0.1 L g-1 solvent proportion. The results of the field experiment showed that the application of water stress during the cultivation of A. unedo plants triggered the biosynthesis of polyphenolic compounds in the leaves, increasing their content from summer until the beginning of autumn. Finally, polyphenolic fruit extracts of A. unedo and M. communis showed to be suitable for the inclusion in whey, maintaining their high polyphenolic content during storage thus proving their possible application as functional additives in the food industry. In conclusion, all the selected species provided extracts with high yields of polyphenols to be applied in the pharmaceutical and nutraceutical sectors, thus the cultivation of these plants may represent an alternative source of income for farmers in the Mediterranean drought-stressed areas

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