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Статті в журналах з теми "Extraction assistée par enzyme et ultrasons"
Adjou, ES, H. Amamion, FP Tchobo, VM Aissi, and MM Soumanou. "Extraction assistée par enzyme du jus de la pulpe fraîche du rônier (Borassus aethiopum Mart.) acclimaté au Benin : caractérisation physico-chimique et microbiologique." International Journal of Biological and Chemical Sciences 7, no. 3 (October 25, 2013): 1135. http://dx.doi.org/10.4314/ijbcs.v7i3.20.
Повний текст джерелаДисертації з теми "Extraction assistée par enzyme et ultrasons"
Davidson, Morag. "Éco-extraction de composés bioactifs à partir de marcs de fruits rouges & étude de leur impact sur l'homéostasie intestinale." Electronic Thesis or Diss., Limoges, 2024. http://www.theses.fr/2024LIMO0020.
Повний текст джерелаSince 2010, 100 million tons of red fruits have been produced globally each year. 20% of wastes result from their first industrial transformation, which includes the seeds and the skins, known as pomace. While spreading and animal feeding are common ways to valorise these wastes, they are also a potential source of hydrophilic and lipophilic bioactive compounds (fibres, proteins, polyphenols, minerals & poly-unsaturated fatty acids, phytosterols, tocols). Therefore, it is interesting to design simultaneous extraction processes to extract simultaneously all of these biomolecules to fully exploit their biological activities.This thesis aimed to achieve two goals. The first goal was to develop an innovative extraction process by combining the use of an enzyme(s) with the use of ultrasounds to extract simultaneously, in an aqueous medium, the hydrophilic and lipophilic bioactive compounds of red fruit pomaces. The second goal was to assess in vitro the prebiotic properties of the extracts.The thesis was divided into four successive steps: (i) the characterisation of the proximate compositions of the raspberry, strawberry, blackberry and black currant pomaces, (ii) the design of one or several eco-extraction process(es), (iii) the global chemical characterization of the “eco-extracts” and (iv) the in vitro assessment of their potential prebiotic properties.The design of the eco-extraction process was divided into three steps. First, three enzymes (a cocktail of glycohydrolases, an acid protease and an alkaline protease) were tested, alone or sequentially combined. Secondly, the selected enzymatic systems were associated with ultrasounds, either simultaneously (enzyme + ultrasounds) or sequentially (enzyme → ultrasounds and ultrasounds → enzyme). The choice of the enzymatic system(s) and their combination with ultrasounds was based on their extraction efficiencies, ease of implementation and innovative character compared to existing literature. Finally, the selected combination(s) were optimised by an experimental design (Definitive Screening Design) by adjusting six parameters comprising three levels: ultrasound amplitude, pH, enzyme/substrate ratio, solid/liquid ratio, extraction time and temperature.The simultaneous combination “alkaline protease-ultrasounds” was selected and optimised for the raspberry, strawberry and blackberry pomaces. All of the polyphenols, with 75% of their antioxidant capacities, and 75% of the oil present in the pomaces were extracted in a single step in an aqueous medium. The optimised simultaneous combination “acid protease-ultrasounds” extracted 75% of the polyphenols, with the totality of the anthocyanins, and 50% of the oil of the black currant pomace.The eco-extracts demonstrated prebiotic properties towards probiotic bacteria (Lactobacillus plantarum 299v, Lactobacillus rhamnosus) by favouring their growth. This makes them potential candidates for the nutraceutical industry. The eco-extracts could be integrated into dietary complements to maintain or restore the intestinal microbiota balance
Puspita, Maya. "Extraction assistée par enzyme de phlorotannins provenant d’algues brunes du genre Sargassum et les activités biologiques." Thesis, Lorient, 2017. http://www.theses.fr/2017LORIS440/document.
Повний текст джерелаIn France and Indonesia, Sargassum is quite abundant yet this alga has not been optimally exploited. Sargassum contains macro and micro molecules and also bioactive compounds, the most known is phlorotannins, showing a wide range of pharmacological properties. Therefore, it is interesting to further valorize this alga. The heterogeneity and complexity of algal cell wall strongly reduces the extraction efficiency application of conventional extraction. Subjects of interest in this study were to characterize the seasonal variation of Sargassum biochemical composition and to extract phlorotannins using conventional and alternative method, i.e. solid-liquid and enzyme- assisted extraction. In this study, minerals represented a significant value with a content reaching 33% followed by proteins with 24% of algal dry material. In the contrary, sugars showed only 13% of algal dry material. Further, the biochemical composition of Sargassum, like most algae, was highly affected by the seasons and related to Sargassum life cycle. In terms of polyphenol compounds in Sargassum, season might be the most influential factor but suitable methods of extraction determine the efficiency to collect these compounds from Sargassum. Solid-liquid extraction, in certain extent, yielded lower (ranging from 5 to 24% of dry algal material) than the enzyme-assisted extraction (ranging from 21 to 38% of dry algal material). Concerning the polyphenol content of Sargassum extracted with these two methods, enzyme-assisted extraction, in certain extent, had higher content than the solid-liquid extraction. Enzymatic extracts showed a strong antiradical activity
Beaudor, Maxime. "Valorisation en cascade du marc de café via les procédés d'extraction assistée par ultrasons et de fermentation en milieu solide." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR044.
Повний текст джерелаCoffee is one of the most popular beverages. According to the International Coffee Organization, between 2017 and 2022, its production increased by 2.2%, while consumption grew by 7.7%. The sole solid co-product resulting from aqueous extraction to obtain the caffeinated hot beverage is spent coffee grounds. This bio-waste represents approximately 6 million tons annually.The primary objective of this thesis is to define and evaluate a cascade valorization approach for spent coffee grounds, aiming to progressively and efficiently exploit this resource to generate various industrially valuable products. To achieve this goal, two processes were selected. Firstly, solid-liquid eco-extraction, including ultrasound-assisted extraction, was used for the recovery of antioxidant phenolic compounds from spent coffee grounds. Subsequently, in a sequential manner, solid-state fermentation was implemented on the depleted grounds with the assistance of Penicillium solitum to produce a hydrolytic enzyme cocktail.The valorization cascade was applied to a type of spent coffee grounds collected and stored by the Gecco company (SCG-1), sourced from bars and restaurants in the Hauts-de-France region. Fresh marc from the thesis host laboratory (SCG-2) was also investigated to gain a better understanding of the industrial constraints related to storage. The comparison of two extraction methods applied to SCG-1, conventional extraction (CE) and ultrasound-assisted extraction (UAE), revealed the positive influence of ultrasound on the recovery of antioxidant phenolic compounds. UAE enabled the extraction of approximately 30% more total polyphenols (11.8 vs. 9.1 mg GAE/g) and consumed at least 3 times less energy (170 vs. 630 Wh) under optimal extraction conditions (50-50 (v/v) water-ethanol, 40 mL/g, power of 571 W/L for UAE, or temperature of 70°C for CE). The application of these optimized conditions to SCG-2 resulted in a 23% additional antioxidant activity (77.9 vs. 63.5 µmol Trolox/g) in the extract compared to SCG-1.The phenolic compound extract obtained from SCG-2 under optimized UAE conditions showed the presence of chlorogenic acids commonly found in spent coffee grounds, with concentrations of 4.3 mg/g, 5.9 mg/g, and 0.4 mg/g for 3-CQA, 5-CQA, and 3,5-diCQA, respectively. These three compounds were absent in the extract obtained under the same conditions from SCG-1, which exhibited the presence of other antioxidant compounds formed during storage by various colonizing micro-organisms.Following the isolation and identification of around forty filamentous fungi present on SCG-1, Penicillium solitum was selected for optimizing solid-state fermentation (SSF) to produce a hydrolytic enzyme cocktail. The optimized extraction conditions (7 mL/g, 55 minutes) and fermentation conditions (74.1% moisture, 7 days of incubation, and an inoculum of 10^7 spores/g) obtained through modeling allowed for the production of an enzymatic complex with lipase, mannanase, and glucanase activities on SCG-1. Regarding the production of these same enzymes on SCG-2, the optimal fermentation conditions were (75% humidity, 7 days of incubation, and an inoculum of 8.1x10^6 spores/g). The activities calculated under these conditions for both types of spent coffee grounds were 65.3 and 49.5 U/g for lipase activity, 948 and 939 mU/g for mannanase activity, and 295 and 206 mU/g for glucanase activity, respectively, for extracts obtained from fermentations on SCG-1 and SCG-2. Additionally, the optimized extract produced on SCG-1 by Penicillium solitum also exhibited other measured activities, with 56.4 U/g, 626 mU/g, and 856 mU/g, respectively, for protease, xylanase, and pectinase activities
Burlot, Anne-Sophie. "Valorisation des métabolites d'algues proliférantes par voie enzymatique : applications dans les domaines de la nutrition et santé animale, végétale et humaine, de la cosmétique et de l'environnement." Thesis, Lorient, 2016. http://www.theses.fr/2016LORIS428/document.
Повний текст джерелаThese last decades, Solieria chordalis (Rhodophyta, Gigartinales), a red and proliferative macroalga appears every year in south of Brittany on the peninsula of Rhuys. It is a question of removing more than 2 000 tons of red seaweeds, mainly composed of S. chordalis. These proliferations represent a true ecological problem and an economic constraint for the affected communities. This project aims to study S. chordalis in order to find a way to add more value to this seaweed by proposing a rational and sustainable management as well as potential applications. From October 2013 to October 2015, S. chordalis was collected monthly. Results have shown seasonal variations of the biomass on the shores, in the macro- and microscopic morphologies, in the dry matter rate and in the biochemical composition. In relation with the seasonal environmental factors, it is now possible to estimate the quantity and the biochemical composition of the seaweed and to propose potential applications. With characteristics of high catalytic efficiency, specificity, the environmental-friendly process of Enzyme-Assisted Extraction was chosen to produce water- soluble extracts with antiviral, antibacterial and immunostimulant activities. The commercial protease Alcalase improved the extraction yield with a significant gain of 30 % of the water-soluble and free compounds compared to an extraction without the action of enzymes. Almost 60 % of the dry matter of algae was liquefied and water-solubilized after the optimization of extraction parameters. Water-soluble extracts produced after the action of enzymes have shown anti- herpetic activities (EC50 from 86.0 to 145.9 µg/mL) and no cytotoxicity was detected. The immunostimulant activity was evaluated by using the pathogenicity model Caenorhabditis elegans Pseudomonas aeruginosa. The life span of infected nematods by pathogen bacteria increased after the application of water-soluble extracts from S. chordalis. Some immune genes of C. elegans were stimulated (zk6.7, spp-1, f28d1.3 and f38a1.5). Produced extracts present antiviral and immunostimulant activities that allow to anticipate applications for diverse domains
Fournière, Mathilde. "Extraction et évaluation des propriétés biologiques des ulvanes et oligo-ulvanes de l'algue verte Ulva sp. : actions sur le métabolisme de cellules cutanées et sur le microbiote cutané." Electronic Thesis or Diss., Lorient, 2021. http://www.theses.fr/2021LORIS593.
Повний текст джерелаUlvans are matrix sulfated polysaccharides constitutive of green seaweed Ulva sp. cell wall. Although proliferative and quantitatively available, Ulva sp. is little valued with applications in low added value sectors. The objective of this project is to produce fractions enriched in ulvans and oligo-ulvans in order to evaluate their biological properties on cutaneous system. Ulvan fractions were produced by maceration and enzyme-assisted extraction followed by different purification processes: ethanolic precipitation and dialysis. Radical and acid depolymerization processes allowed to obtain oligo-ulvan fractions. Ulvan and oligo-ulvan fractions have been shown to stimulate human dermal fibroblasts proliferation. An increase in the synthesis of extracellular matrix components such as type I and III collagens, and glycosaminoglycans has been demonstrated. Fractions also stimulate the expression, synthesis and MMP-1 enzymatic activity. At the skin microbiota level, the fractions do not alter the growth of commensal bacteria S. epidermidis, S. aureus and C. acnes, but may modify the biofilm formation. Ulvan and oligo-ulvan fractions also reduce the inflammatory potential of HaCaT keratinocytes induced by C. acnes. Thus, this work has shown that the ulvan and oligo-ulvan fractions exhibit promising biological activities for dermo-cosmetic applications in tissue repair, anti-ageing or anti-inflammatory strategies while preserving commensal skin microbiota
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." Phd thesis, Université d'Avignon, 2010. http://tel.archives-ouvertes.fr/tel-00543792.
Повний текст джерелаDary, 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.
Повний текст джерелаThe 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)
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.
Повний текст джерелаWith 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
Elagli, Adil. "Contribution à l'intensification de procédés appliqués à la protéolyse enzymatique : Étude microcinétique en réacteur microfluidique et conception assistée par plasma froid d'un microréacteur à enzyme immobilisé." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10032/document.
Повний текст джерелаNew economic and environmental issues previously introduced the concept of process intensification since some years ago. Dealing with the control and the intensification of enzyme processes, this thesis was divided into two parts. The first part focused on the study of enzyme reactions in microreactor from a microkinetic perspective. It was intended to optimize the preparation of an opioid peptide from a proteolytic reaction, the hydrolysis of bovine hemoglobin by porcine pepsin. Firstly, a modulation of the reaction kinetic selectivity was highlighted. Then, on the basis of a sustainable approach, the enzymatic process was coupled to a separative process. It allowed the selective and continuous recovery of the hemorphin LVV-h7 by a sequence of two consecutive liquid-liquid extractions. Through all of the results, the first part of this thesis attempts to highlight some attractive benefits derived of the use of microfluidics in process engineering. Finally, the second part of this thesis has been extended to the design of a microstructured reactor with immobilized enzyme by exclusively using an organosilicon material, TetraMethylDiSiloxane. First, cold plasma technology allowed the development of an original methodology for enzyme immobilization by steric entrapment. Then, by using plasma-assisted polymerization, this protocol was used to design an immobilized enzyme microreactor according to a “bio-integrating” methodology
Bouras, Meriem. "Etude comparative et optimisation de prétraitements des écorces de bois pour l'extraction des composés phénoliques." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2245.
Повний текст джерелаThis research work focuses on the intensification of polyphenols extraction from Quercus robur and Norway spruce barks using innovative technologies : pulsed electric field (PEF), ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE). These pre-treatments enhance the release of intracellular compounds by damaging the membrane and/or cell wall. The effect of each of these technologies (PEF, UAE and MAE) on polyphenols extraction has been highlighted in a quantitative and qualitative optimization analysis by evaluating the polyphenols concentration, antioxidant activity and by the chemical characterization of the extracted compounds.A comparative study of pre-treatments (PEF, UAE and MAE) coupled with an extraction step in an alkaline hydro-alcoholic medium allowed us to better understand the involved phenomena. The induced process efficiency is independent of the tree family to which the bark belongs (coniferous and hardwood). For bark valorization, the application of PEF treatment (20 kV/cm, 200 pulses, 3.2 kJ/g bark) followed by a diffusion step seems to be an alternative to ultrasound and microwave assisted extractions and to the extraction from grinded barks. In fact, the electrical and mechanical effect of PEF treatment allow to obtain an extract rich in polyphenols (10.5 g GAE/100g DM and an efficiency of 83 % for Norway spruce and 5 g GAE /100g DM and an efficiency of 82 % for Quercus robur bark)