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1

Slaughter, Leeann L. "Antilisterial Characteristics of Volatile Essential Oils". UKnowledge, 2013. http://uknowledge.uky.edu/animalsci_etds/16.

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Abstract (sommario):
This study explored the in vitro and in situ antilisterial inhibitory activity of 16 essential oils during indirect exposure: Spanish Basil oil (Ocimum basilicum), Bay oil (Pimenta racemosa), Italian Bergamot oil (Citrus bergamia), Roman Chamomile oil (Anthemis nobilis), Sir Lanka Cinnamon oil (Cinnamomum zeylanicum), Citral, Clove Bud oil (Syzygium aromaticum), Cumin Seed oil (cuminum cyminum), Eucalyptus oil (Eucalyptus globulus), Eugenol, Geranium extract (Pelargonium graveolens), Marjoram oil (Origanum majorana), Neroli extract (Citrus aurantium), Peppermint oil (Mentha piperita L.), Rosemary oil (Rosmarinus officinalis L.),and Spanish Sage oil (Salvia officinalis L.). All essential oils were tested against Listeria monocytogenes (ATCC 4644). In vitro inhibitory activity was determined using the microatmosphere method at three temperatures (37°C, 24°C, 4°C) and six possible volumes (0, 10µl, 25µl, 50µl, 100µl, 150µl, or 200µl). In situ inhibitory activity was determined using inoculated bologna slices packaged in Modified Atmosphere Packaging (80% O2, 20% CO2). Essential oils (0, 0.13ml, 1.35ml, or 2.70ml) were injected into the sample packages adjacent, but not touching, the bologna slices and stored at 24°C for 24h. Basil oil displayed the least antilisterial activity across the three temperature applications in vitro. Peppermint, Cumin Seed, and Citral consistently exhibited the greatest antilisterial activity among the temperature applications in vitro. However, only Eugenol applied at 1.35ml achieved a mean one log10 CFU/ml reduction in LM in situ, which could not be replicated. Peppermint (P < 0.048) displayed significant differences between application volumes (0.13ml, 1.35ml) but did not attain a mean one log10 CFU/ml reduction in LM. This study suggests that while various essential oils can display antilisterial activity in vitro, transitioning into a MAP food system warrants further research in mode of actions and application volumes.
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2

Gersbach, Paul Vincent, University of Western Sydney e of Science Technology and Environment College. "Aspects of essential oil secretion in vascular plants". THESIS_CSTE_XXX_Gersbach_P.xml, 2001. http://handle.uws.edu.au:8081/1959.7/775.

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Abstract (sommario):
A study of some aspects of essential oil secretion in plants was conducted. The first part of the study involved analysis of the volatile terpenoid content and composition of leaf extracts from a range of Australian native plants by gas chromatography and mass spectrometry. Secretory structures were studied by several microscopic imaging techniques including conventional bright and dark field optical microscopy, confocal microscopy, and scanning (SEM) and transmission (TEM) electron microscopy. Three methods were employed for scanning electron microscopy. Sample material was prepared for conventional SEM by chemical fixation and rapid freeze fixation, and fresh material was imaged by environmental SEM. These methods were compared, and the images acquired by environmental SEM were invariably of a superior standard as the biological integrity of the samples was retained throughout, and the samples were free of process-induced artefacts. Several other tests were conducted and results discussed in some detail. In the final part of the study, aspects of essential oil secretion were examined by histochemical methods. The first of these was a new method based on traditional approaches to histochemistry. The monoterpene phenols thymol and carvacrol were located in glandular trichomes of Lamiaceae species by means of a colour-change reaction of the phenols with a nitrosophenol/acid reagent. The second used magnetic resonance imaging by a chemical shift selective method to locate, non invasively, the aromatic monoterpenes thymol and anethole in secretory structures in the fruit of Carum copticum (Apiaceae) and the leaves of Backhousia anisata (Myrtaceae) respectively.
Doctor of Philosophy (PhD) (Science)
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3

Rahman, S. M. Ashrafur. "Experimental investigation of essential oils in a diesel engine". Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/121763/2/__qut.edu.au_Documents_StaffHome_StaffGroupH%24_halla_Desktop_S.%20M.%20Ashrafur%20Rahman%20Thesis.pdf.

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The potential use of waste stream essential oils were evaluated as fuel supplements for diesel vehicle/machinery used by producers of these oils. Orange, eucalyptus and tea tree oils were selected; which are native to and/or extensively cultivated throughout Australia. These essential oils are mainly used in the medical and natural therapy sector as well as fragrance and flavouring industry. The high quality of the final product leads to a significant very low value waste stream. Engine performance and emissions evaluation showed that essential oils are comparable to diesel fuel. Their use will help to reduce diesel dependency and fuel costs.
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4

Mam, Rashid Sirwan Ahmed. "Encapsulation of essential oils in food grade materials". Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15702/.

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Abstract (sommario):
The objective of this study was firstly to assess the ability of liquid skimmed milk in combination with different concentrations of maltodextrin (MD) to emulsify 5% w/w thyme essential oils (EOs). Secondly, to analyse the chemical composition of the used thyme EOs and further examine the physical properties of some EOs components such as solubility, surface activity and partitioning coefficient. Moreover, assessing the antibacterial activity of free and encapsulated EOs in vivo and in vitro mediums. From the results of thyme EOs analysis, 29 compounds were identified that containing different terpenes. The results show that skimmed milk with MD performed as an excellent delivery system for emulsifying thyme EOs with high stability for 60 days and formation of small size droplets < 234 nm. The produced powders obtained by spray drying the initial emulsions were analysed, and the results showed that increasing the concentration of MD from zero to 3 % w/w decreased surface oil, retained higher amounts of EOs with the encapsulation efficiency reaching up to 97.4 %. The antibacterial activity against Escherichia coli and Staphylococcus aureus was assessed by using free and encapsulated thyme EOs in the form of the solution or direct addition to the inoculum or food products. The minimum inhibitory concentration (MIC) was lowest 0.3 mg/mL against both Escherichia coli and Staphylococcus aureus, when encapsulated EOs was directly added to the inoculum and prolonged shelf-life of both skimmed and unpasteurised raw milk were attained with the same formulation. Furthermore, the food matrices had a great role in decreasing the antibacterial activity of EOs by decreasing the availability of the active components and preserving the bacteria cells from them. The encapsulation of EOs increased the bioactivity of thyme EOs. The combination of EOs and low temperatures had a significant role in increasing the shelf-life of whole unpasteurised milk.
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5

Low, Wan Li. "Lipsome encapsulated antimicrobial metal ions and essential oils". Thesis, University of Wolverhampton, 2012. http://hdl.handle.net/2436/219012.

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Abstract (sommario):
This study investigates the feasibility of using TTO and Ag+ alone and in combination either as free or liposome encapsulated agents. Based on the minimum lethal concentration (MLC), the fractional lethal concentration index (FLCI) showed that treatment with unencapsulated combinations of TTO and Ag+ exerted a synergistic effect against P. aeruginosa (FLCI = 0.263) and indifferent effects against S. aureus and C. albicans (0.663 and 0.880, respectively). Using polyvinyl alcohol (PVA) emulsified agents in combination, showed synergistic effects against P. aeruginosa and S. aureus (FLCI = 0.325 and 0.375, respectively), but C. albicans remained indifferent (FLCI = 0.733). Time kill experiments revealed that the combined agent concentrations and elimination time (to the lowest limit of detection, LOD) are as follows: C. albicans: 0.12%v/vTTO:2.5x10-4Ag+:1.5hrs, P. aeruginosa: 1%v/vTTO:3.2x10-4Ag+:15mins and S. aureus: 1.2%v/vTTO:3.2x10-4Ag+:30mins. Repeating these experiments with emulsified TTO encapsulated in liposomes (lipo-TTO:PVA30-70kDa) against P. aeruginosa and S. aureus reduced the effective amount of TTO required (compared to free TTO). However, this was not observed in C. albicans. The required effective concentration of Ag+ from liposome encapsulated Ag+ (lipo-Ag+) was shown to remain the same as free Ag+. The effective concentration and elimination time of liposomal agents in combination are as follows: C. albicans: 0.05%v/vTTO:PVA:8.9x10-5Ag:PVA:2.0hrs, P. aeruginosa: 0.25%v/vTTO:PVA:3.2x10-4Ag:PVA:30mins and S. aureus: 0.05%v/vTTO:PVA:6.0x10-4Ag:PVA:1.5hrs. These results showed the potential of using TTO and Ag+ in combination, along with liposome delivery systems to effectively lower the MLC. Scanning electron micrographs of microorganisms exposed to Ag+ showed a reduction in cell size when compared to untreated cells. Transmission electron micrograph of C. albicans showed the cell surface damaging potential of Ag+. Furthermore, this investigation also demonstrated the feasibility of using chitosan hydrogels as an alternative delivery system for TTO and/or Ag+. The development of these controlled release systems to deliver alternative antimicrobial agents may allow sustained targeted delivery at microbiocidal concentrations.
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6

Nunes, Maria João Correia. "Evaluation of minimal inhibitory concentrations of essential oils". Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5268.

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Abstract (sommario):
Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
Essential oils of Origanum vulgare, Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea and Rosmarinus officinalis were evaluated for their antimicrobial activity against Listeria monocytogenes, Pseudomonas aeruginosa and Yarrowia lipolytica using the microdilution method. The most promising essential oil showed to be the Origunum vulgare with an inhibition range of 0,006 to 0,352% (v/v) for the yeasts and from 0,003 to 0,011% (v/v) for the bacteria species, with no significant differences between Gram positive and negative cells. Statistical analysis demonstrated a great variability in the Origanum vulgare and Rosmarinus officinalis oils results for both bacteria and yeasts growth. Data variability was larger as the essential oil concentration increased. The Origanum vulgare essential oil demonstrated to have the most promising capacity to be applied in food models against the assayed microorganisms in a future work.
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7

Бабенко, Наталія Олександрівна. "Aromatherapy: essential oils as an alternative to treatment". Thesis, Київський національний університет технологій та дизайну, 2020. https://er.knutd.edu.ua/handle/123456789/15260.

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8

Bruno, Flores Josue Manuel, García Alejandra Gabriela Castillo, Yañez Natalie Escudero, Bonilla Camila Jimena Hernández e Villacorta Erika Valeria Lopez. "Make it essential". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626527.

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Abstract (sommario):
“Make it essential” es el nombre de nuestro proyecto de negocio que plantea poner fin a una necesidad y problemática que permanece en la sociedad y que, en los últimos años, se ha incrementado de manera significativa en los sectores de educación y laboral como es el estrés, a través de una solución innovadora que les permita llevar una vida más plena. El proyecto se basa en la venta de joyas difusoras de aceites esenciales que cumplen el propósito de aliviar el estrés que es originado por los estudios, el trabajo y también problemas por los que pueda estar pasando la persona. A lo largo del ciclo, hemos logrado validar la idea de negocio a través del planteamiento de hipótesis y la ejecución del Concierge que fue impulsado por las estrategias de marketing en redes sociales. El público logró tener una buena aceptación del producto gracias al valor diferenciado que posee y obtuvo ventas por 212 unidades a la fecha, que están valorizadas en S/. 12,321. Asimismo, la empresa tiene como objetivo crecer con el tiempo, tanto en ventas como en capacidad instalada, con la finalidad de lograr atender la demanda proyectada y expandirse a otros territorios. Es decir, el análisis de viabilidad en un horizonte de 5 años nos indica que el proyecto está valorizado en S/. 47,963 gracias a la proyección de flujos de efectivo traídos a valor presente, lo cual nos indica que el proyecto es viable y sostenible en el tiempo.
"Make it essential" is the name of our business project that proposes to end a need and problem that remains in society and that in recent years has increased significantly in the education and work sectors such as stress, through an innovative solution that allows them to lead a fuller life. The project is based on the sale of jewelry diffusers of essential oils that fulfill the purpose of relieving the stress that is caused by studies, work and also problems that the person may be going through. Throughout the cycle we have managed to validate the business idea through the hypothesis approach and the execution of the Concierge that was driven by social media marketing strategies. The audience managed to have a good acceptance of the product thanks to the differentiated value that it has, achieving sales of 212 units to date that are valued in S /. 12,321. The company aims to grow over time, both in sales and installed capacity to meet projected demand and expand to other territories. The feasibility analysis over a 5-year horizon tells us that the project is valued in S/. 47,963 thanks to the projection of cash flows brought to present value, which tells us that the project is viable and sustainable over time.
Trabajo de investigación
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9

Turek, Claudia [Verfasser]. "Investigations into the Stability of Essential Oils / Claudia Turek". Aachen : Shaker, 2013. http://d-nb.info/1051574048/34.

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10

Andersson, Karin. "Mosquito repellency of essential oils derived from Lao plants". Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-123717.

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Abstract (sommario):
Essential oils or extracts obtained from four plant species growing in Laos were tested foranti-mosquito activity in the field. Solutions of alcohol or acetone containing differentconcentrations of essential oil; 5, 10 or 19 v/v %, were prepared and tested. Mosquitoes werecollected by human baits wearing oil impregnated mosquito nets around their shanks. Thenumber of attracted mosquitoes was compared to the number attracted to positive andnegative controls, i.e., human baits wearing nets impregnated with 19 % N,N-diethyl-metatoluamide (DEET, NN-diethyl-methyl-benzamide) or untreated nets, respectively. A one wayANOVA analysis was conducted on the log-transformed total number of mosquitoes collectedusing each treatment. The statistical analysis showed that significantly fewer mosquitoes wereattracted to the treatment harbouring 19 % oil of Scutellaria angustifolia than to the negativecontrol. No significant decrease in attracted mosquitoes could be detected for the treatmentscontaining oil from the plant Litsea cubeba. However, a tendency of repellency was indicated. Therefore, an investigation running over a longer period of time is desired for Litsea cubeba. No conclusions could be drawn for the remaining two species; Tagetes patula and Citrussinensis.
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11

Kiwanuka, Pauline. "The authentication of citrus essential oils by chromatographic methods". Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390612.

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12

BALLESTEROS, LARA Jose Luis. "CHEMICAL FINGERPRINTING AND BIOACTIVITY PROFILE OF ECUADORIAN ESSENTIAL OILS". Doctoral thesis, Università degli studi di Ferrara, 2018. http://hdl.handle.net/11392/2488237.

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13

Salvesen, Gregory John. "The effects of inhaled bergamot and geranium essential oils on rat behaviour". The University of Waikato, 2009. http://hdl.handle.net/10289/2784.

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Abstract (sommario):
The aim of this study was to evaluate the behavioural effects of inhaled bergamot, geranium and a combination of these oils in three novelty evoked tests of anxiety. Sixty adult Hooded Rats (Rattus norvegicus), with 10 rats randomly assigned to one of the 6 test groups; three essential oil treated groups, and three control groups. The essential oil groups consisted of bergamot, geranium and a combined group, i.e. the combination of bergamot and geranium oil. The control groups consisted of the odour and vehicle control, with the anxiolytic drug diazepam as a positive control. The behaviour of rats was assessed on the elevate-plus maze, open-field and social interaction test. Diazepam increased open arm entries and the time spent in the open arms, decreased time spent in closed arms and increased the number of head-dips and unprotected stretch-attends in the EPM. In the open-field diazepam increased immobility time, decreased ambulation, increased grooming activity and reduced the amount of time spent exploring the arena. Similarly, diazepam decreased the frequency of separations, sniffs, follows, crawls, passive and active interactions with test partners in the social interaction test. Bergamot, geranium and the combination of the two oils increased total arm entries in the elevated-plus maze. Bergamot increased locomotion and exploratory behaviour in open-field and decreased contact latency and increased passive and active interaction between the rat pairs in the social interaction test. Geranium decrease immobility and increase the time spent rearing in the open-field and also increased active interaction, i.e. partner sniffing and decreased the amount of time the rat pairs spent apart in the social interaction test. The combination of bergamot and geranium oil increased locomotion and the time spent in Zone2, and also increased exploratory behaviour, i.e. the frequency and duration of rears in the open-field. In the social interaction test, contact latency was shortened and active and passive interactions between rat pairs were increased by the combination of essential oils. The present study established that bergamot, geranium, and the combination of the two oils had a stimulating effect in the elevated-plus maze and an anxiolytic effect in the open-field and social interaction tests when inhaled. Furthermore the study also demonstrated that the combining of the oils had a potentiating effect on the anxiolytic properties of the single oils.
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14

Olleveant, Nicola Alaine. "Physiological and psychological effects of aromatherapy massage on critically ill patients". Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275050.

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15

Riley, C. J. "Numerical modelling of supercritical fluid extraction". Thesis, Cranfield University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241841.

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16

Gersbach, Paul V. "Aspects of essential oil secretion in vascular plants /". View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20031223.143208/index.html.

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Thesis (Ph.D.) -- University of Western Sydney, 2001.
"This thesis is presented in fulfilment of the degree of Doctor of Philosophy in Science at the University of Western Sydney, Richmond, New South Wales, Australia" Bibliography : p. 145-163.
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17

Smith-Palmer, Mary Alison. "The antimicrobial properties of plant essential oils against foodborne pathogens". Thesis, Queen Margaret University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327082.

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18

Serra, Elisa. "A hydrogel in combination with essential oils for oral therapy". Thesis, Manchester Metropolitan University, 2018. http://e-space.mmu.ac.uk/622355/.

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Abstract (sommario):
Oral diseases such as periodontal diseases and oral candidiasis are significant health problems in humans. Periodontal disease is a common disease of the oral cavity and the major cause of tooth loss in adults. Four clinical forms of primary oral candidiasis are recognised, and the management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. The use of hydrogels in delivery of biocides has been explored due to their biocompatibility, ease with which they can be charged with drugs, and potential to confer mechanical and structural properties similar to biological tissue. This can be used both for anaerobic bacteria and fungal (i.e. Candida) infections to treat a wider spectrum of oral diseases. The aim of this study was to develop a novel antimicrobial therapy for oral diseases by utilising a hydrogel in combination with Melissa officinalis essential oil. A range of essential oils and biocides has been tested for their antifungal properties mainly against Candida albicans in a planktonic and biofilm growth form and against bacterial species associated with periodontal disease (in the planktonic growth form). The cytotoxicity of the compounds that showed the best antimicrobial properties were tested and the chosen essential oil was incorporated into a methylcellulose hydrogel. Finally, an ex vivo rodent mandible model to mimic oral candidiasis was developed. Antimicrobial screening showed Melissa officinalis to be the most successful essential oil relating to antimicrobial properties and cytotoxicity. The infection of the rodent mandible showed C. albicans invasion of the gingiva and the release of pro-inflammatory cytokines. The application of Melissa officinalis oil significantly decreased the CFU/ml and the pro-inflammatory response. One percent (1% (v/v)) and 2% (v/v) Melissa officinalis oil was successfully incorporated into 10% (w/w) and 12% (w/w) methylcellulose hydrogel. Rheology revealed that the hydrogel was injectable and gellified in two minutes at 37 °C. The drug release was a function of the Melissa officinalis concentration and the loaded hydrogel successfully inhibited Candida growth in vitro. A 3D ex vivo rodent mandible model to mimic oral candidiasis was developed and used to test the antifungal properties of Melissa officinalis oil. Moreover, a potentially injectable methylcellulose hydrogel loaded with Melissa officinalis oil was synthesised. This hydrogel was shown to elicit antifungal properties in vitro. In conclusion, the study showed that essential oils were antimicrobial and that methylcellulose hydrogels could be used as drug delivery systems.
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19

Azad, Mohammad Fallah, Andreas Schwiertz e Holger F. R. Jentsch. "Adjunctive use of essential oils following scaling and root planing". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-204927.

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Abstract (sommario):
Background: Hitherto no study has been published on the effect of the adjunctive administration of essential oils following scaling and root planing (SRP). This study describes the effect of a mouthrinse consisting of essential oils (Cymbopogon flexuosus, Thymus zygis and Rosmarinus officinalis) following SRP by clinical and microbiological variables in patients with generalized moderate chronic periodontitis. Methods: Forty-six patients (aged 40–65 years) with moderate chronic periodontitis were randomized in a double-blind study and rinsed their oral cavity following SRP with an essential oil mouthrinse (n = 23) or placebo (n = 23) for 14 days. Probing depth (PD), attachment level (AL), bleeding on probing (BOP) and modified sulcus bleeding index (SBI) were recorded at baseline and after 3 and 6 months. Subgingival plaque was taken for assessment of major bacteria associated with periodontitis. Results: AL, PD, BOP and SBI were significantly improved in both groups after three (p < 0.001) and 6 months (p ≤ 0.015). AL improved significantly better in the test than in the control group after 3 and 6 months (p < 0.001), so did PD after three months in the tendency (p = 0.1). BOP improved better in the test group after 3 months (p = 0.065). Numbers of Treponema denticola (p = 0.044) and Fusobacterium nucleatum (p = 0.029) decreased more in the test than in the control group after 3 months, those of Tannerella forsythia after 6 months (p = 0.039). Prevotella micra (p < 0.001,p = 0.035) and Campylobacter rectus (p = 0.002,p = 0.012) decreased significantly in both groups after 3 months. Conclusions: The adjunctive use of a mouthrinse containing essential oils following SRP has a positive effect on clinical variables and on bacterial levels in the subgingival biofilm.
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20

Pardede, Joseph Jupiter. "The separation and analysis of essential oils from wax flowers". Thesis, Pardede, Joseph Jupiter (1994) The separation and analysis of essential oils from wax flowers. PhD thesis, Murdoch University, 1994. https://researchrepository.murdoch.edu.au/id/eprint/51881/.

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Abstract (sommario):
The botanical genus Chamelaucium, commoiily called Geraldton wax, contains a number of species which are highly valued in the cut-flower industry. The coloured flowers and green foliage together with the fragrant odour of cuttings from Chamelaucium shrubs have contributed to the significant growth in demand (both local and export) for attractive flower arrangements. Despite the economic interest in the Chamelaucia there has been little scientific research focused on the members of this genus which is native to a small area within the state of Western Australia. Information about the taxonomy of the entire genus has not been systematically described and there exists no information about the chemical compounds that are produced by members of this genus. This work describes a systematic study of this genus undertaken at Murdoch University. The focus of this research were the monoterpenoid compounds that are produced by members of the Chamelaucium genus. This aspect was selected because of the availability of vapour phase chromatographic equipment within the department and the prospective importance of the volatile oils that can be obtained from the genus. The establishment of organised plantations of Chamelaucia now provide access to many kilograms of oils from the prunings and off-cuts that are currently burnt or composted. This study systematically examined the essential oils produced by this genus. Methods for the separation of these oils from the plant material were examined and evaluated. The profiles of monoterpenoid compounds produced by Chamelaucium uncinatum during an annual cycle were observed. The profile of monoterpenoid compounds from all the available members of the genus was examined and subjected to multivariate analysis. The results from this multivariate data analysis were then compared to the taxonomy of this genus as it is currently understood. The methods used in the study for comparing and identifying monoterpenoid components in essential oils were examined and analysed.
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ANTONINI, STEFANO. "Interference of Essential Oils on the Motility of Anisakis Larvae". Doctoral thesis, Università degli Studi di Camerino, 2014. http://hdl.handle.net/11581/401768.

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A variety of essential oils have been used since antiquity in the treatment of different infectious diseases. Several nematicidal compounds have been isolated from plants and some essential oils and their components have been evaluated for their nematicidal activity, such as essential oils of Pelargonium graveolens, Ocinum sanctum, Ocimum basilicum, Mentha piperita, and M. spicata and their main components (citronellol, eugenol, geraniol, and linalool). The lack of compounds for the effective treatment of anisakiasis combined with reports on the biocidal activity of different products of natural origin prompted research into the activity of various vegetable extracts and essences or their components against A. simplex third-stage larvae. A group of researchers from Spain demonstrated the activity of some essential oils against A. simplex. Taking into account this background, the objective of this PhD thesis was to evaluate the in vitro effects of different essential oils, neem oil, and trans-anethole on the motility of L3 of Anisakis simplex. In order to obtain more accurate data about the interference of EO on the motility of third-stage larvae, the possible application of an apparatus for imaging and tracking worms inside an incubator was investigated. Given the increasing consumption of fishery products, a preliminary study on the prevalence of Anisakid parasites in fish species commonly found in the Italian seas was also conducted.
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Lale, N. E. S. "Insecticidal activity of plant essential oils on Callosobruchus maculatus (F.) : (Coleoptera:Bruchidae)". Thesis, University of Newcastle Upon Tyne, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379315.

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23

Hili, Pauline. "Essential oils : antimicrobial activity and the effects on membrane lipid activity". Thesis, University of Westminster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263926.

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24

Williams, Brittney E. "Essential Oils in Combination and Their Effect on E. coli Growth". Ohio University Art and Sciences Honors Theses / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ouashonors1524752078918456.

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25

Miller, Andrew B. "Antimicrobial and Anticancer Activity of Essential Oils from Guatemalan Medicinal Plants". BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2411.

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Guatemalan medicinal plants were collected and screened for the presence of essential oils using steam distillation. Oil was found in 63 species from 24 families and was tested in tube dilution assays for activity against Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Lactobacillus acidophilus and Candida albicans. Several essential oils were highly active with 20 instances of oils inhibiting the microbes at an MIC of 0.31 µl/ml. Oils were also tested against cancerous and established cell lines using a 15% (v/v) agar-media which was developed to improve essential oil solubility. Assays were performed against three cancer lines: Stomach (AGS: CRL-1739), Skin (A375: CRL-1619), Tongue (CAL27: CRL-2095) and an established Monkey Kidney cell line (Vero C 1008: CRL-1586). Assessment of viability was performed using the Neutral Red assay with results indicating that many of the oils significantly inhibited cancer cell lines in vitro with 24 individual instances producing an IC50 of 0.20 µl/ml or less. Therapeutic indices indicated that many of the highly inhibitory oils were more cytotoxic to cancerous cell lines than to the established cell line.
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26

Nyiramana, Lunianga Marie. "Stratégies de mise en marché des huiles essentielles québécoises /". Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1991. http://theses.uqac.ca.

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27

Clark, Amanda. "Melaleuca Alternifolia Concentrate (MAC): A Plant-Derived Anticancer Agent". Thesis, Griffith University, 2013. http://hdl.handle.net/10072/367678.

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Natural products historically represent a source of clinically approved drugs that have contributed significantly to anticancer drug development. In particular, essential oils represent a group of advantageous anticancer candidates as not only can they be produced in large quantities in a cost-effect manner but they also exhibit minimal toxicity. Melaleuca alternifolia Concentrate (MAC) is an extract prepared from the native Australian plant M. alternifolia (also a common source of Tea Tree Oil). Melaleuca oils are commonly used products, primarily utilised and investigated for their antimicrobial activity. However, over the last 2 decades, a continued stream of evidence has been produced pertaining to the anticancer potential of Melaleuca oil and its constituents. Previous studies reported Melaleuca oils to exhibit anticancer activity in vitro against a range of cancer cell lines, including melanoma, liver, leukaemia, lung, breast, and prostate cancer. However, much still remains to be discovered and elucidated about the Melaleuca oils, TTO and MAC. This thesis investigated the hypothesis that MAC represented an effective anticancer agent with immunomodulatory activity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Medical Science
Griffith Health
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28

Phillips, Alicia Kyser Appel Arthur G. "Toxicity and repellency of essential oils to the German cockroach (Dictyoptera: Blattellidae)". Auburn, Ala., 2009. http://hdl.handle.net/10415/1942.

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29

Oddo, Martina. "Effects of different weed control practices on soil quality in Mediterranean crops". Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/90655.

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Effects of different weed control practices on soil quality in mediterranean crops This research approaches the question of weed control sustainability, from the point of view of soil quality maintenance and enhancing. A big choice of practices and products for weed control are available nowadays, but the actual definition of "sustainable practice" not always considers soil fertility. Soil processes timescale is wider than the productive, commercial and legislative ones. Also the definition of survey protocols is a process slower than the evolution of weed control methods. The faster reaction in the soil ecosystem after an external pressure is given by the organisms living in it, and the microbial community is finally the most effective agent in nutrient recycling processes. In this investigation, the same soil analysis protocol was applied on soil samples exposed to different weed management and control methods. Using soil quality indexes and bioindicators, soil properties variations after the different weed control treatments were compared. In particular soil carbon pool and how microbial community recycles was surveyed. A standard protocol to both find variations in long-term soil quality and survey the short-term impact of weed control practices on soil biological processes was defined. Weed management practices can interact with the nutrients recycling processes performed by the microorganisms living in the soil. These processes have a central role in maintaining soil fertility, one of the most important resources for agriculture. Three weed management practices were compared: the use of synthetic (oxyfluorfen) or natural (essential oils and aqueous extracts) herbicides and two mechanical methods (tillage and mulching). Soil fertility was monitored measuring soil physical-chemical values and elaborating soil quality indexes and bioindicators.
Efectos de diferentes prácticas de control de arvenses sobre la calidad del suelo en cultivos mediterráneos Esta investigación aborda la cuestión de la sostenibilidad del control de las plantas arvenses, desde el punto de vista del mantenimiento y mejora de la calidad del suelo. Una gran variedad de prácticas y productos para el control de las arvenses están disponibles hoy en día, pero la definición real de "práctica sostenible" no siempre considera la fertilidad del suelo. La escala de tiempo de los procesos del suelo es más amplia que los procesos productivos, comerciales y legislativos. También la definición de protocolos para la investigación es un proceso más lento que la evolución comercial de los métodos de control de malas hierbas. La reacción más rápida en el ecosistema del suelo después de una presión externa es dada por los organismos que viven en ella, y la comunidad microbiana es el agente más eficaz en los procesos de reciclaje de nutrientes. En esta investigación se aplicó el mismo protocolo de análisis de suelo en muestras de suelo expuestas a diferentes métodos de manejo y control de arvenses. Utilizando índices de calidad del suelo y bioindicadores, se compararon las variaciones de propiedades del suelo después de los diferentes tratamientos de control de arvenses. En particular se estudiaron la reserva de carbono en el suelo y la forma en que la comunidad microbiana recicla. Se definió un protocolo estándar para encontrar variaciones en la calidad del suelo a largo plazo y para analizar el impacto a corto plazo de las prácticas de control de arvenses en los procesos biológicos del suelo. Las prácticas de manejo de malas hierbas pueden interactuar con los procesos de reciclaje de nutrientes realizados por los microorganismos que viven en el suelo. Estos procesos tienen un papel central en el mantenimiento de la fertilidad del suelo, uno de los recursos más importantes para la agricultura. Se compararon las prácticas de manejo de arvenses de frutales: el uso de herbicidas sintéticos (oxyfluorfen) o naturales (aceites esenciales y extractos acuosos) y dos métodos mecánicos (labranza y mulching). Se monitoreó la fertilidad del suelo midiendo los valores físico-químicos del suelo y elaborando índices de calidad del suelo y bioindicadores.
Efectes de diferents pràctiques de control d'arvenses sobre la qualitat del sòl en cultures mediterrànies Aquesta investigació aborda la qüestió de la sostenibilitat del control de les plantes arvenses, des del punt de vista del manteniment i millora de la qualitat del sòl. Una gran varietat de pràctiques i productes per al control de les arvenses estan disponibles avui en dia, però la definició real de "pràctica sostenible" no sempre considera la fertilitat del sòl. L'escala de temps dels processos del sòl és més àmplia que els processos productius, comercials i legislatius. També la definició de protocols per a la investigació és un procés més lent que l'evolució comercial dels mètodes de control de males herbes. La reacció més ràpida en l'ecosistema del sòl després d'una pressió externa és donada pels organismes que hi viuen, i la comunitat microbiana és l'agent més eficaç en els processos de reciclatge de nutrients. En aquesta investigació es va aplicar el mateix protocol d'anàlisi de sòl en mostres de sòl exposades a diferents mètodes de maneig i control d'arvenses. Utilitzant índexs de qualitat del sòl i bioindicadors, es van comparar les variacions de propietats del sòl després dels diferents tractaments de control d'arvenses. En particular es van estudiar la reserva de carboni en el sòl i la forma en què la comunitat microbiana el recicla. Es va definir un protocol estàndard per trobar variacions en la qualitat del sòl a llarg termini i per analitzar l'impacte a curt termini de les pràctiques de control d'arvenses en els processos biològics del sòl. Les pràctiques de maneig de males herbes poden interactuar amb els processos de reciclatge de nutrients realitzats pels microorganismes que viuen a terra. Aquests processos tenen un paper central en el manteniment de la fertilitat del sòl, un dels recursos més importants per a l'agricultura. Es van comparar les pràctiques de maneig d'arvenses de fruiters: l'ús d'herbicides sintètics (oxyfluorfè) o naturals (olis essencials i extractes aquosos) i dos mètodes mecànics (conreu i mulching). Es va monitorejar la fertilitat del sòl mesurant els valors fisicoquímics del sòl i elaborant índexs de qualitat del sòl i bioindicadors.
Oddo, M. (2017). Effects of different weed control practices on soil quality in Mediterranean crops [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90655
TESIS
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30

Rahman, Yosra Ahmed Soltan Abd El. "Effect of tanniniferous plants and essential oils on methane emission in ruminants". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/64/64134/tde-26092012-134451/.

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Tannins and essential oils are secondary metabolites that may be used as natural modifiers of rumen fermentation to reduce the ruminants\' methane (CH4) emission. To study the application of tannin-rich plants from Egypt and Brazil, as well as essential oils that are available in international trade, three studies were conducted at Animal Nutrition Laboratory of Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, at Piracicaba, Brazil. The first study was aimed to assess the potential of tanniniferous plants prosopis (Prosopis juliflora), acacia (Acasia saligna), atriplex (Atriplex halimus) and leucena (Leucaena leucocephala) in in vitro gas production assay, evaluating the methanogenic activity, ruminal fermentation, degradability and post ruminal protein digestibility compared with Tífton hay (Cynodon spp.) as non tannin feed. The ranking of the plants according to their potential to reduce CH4 based on organic matter truly degraded (OMTD) was acacia> leucena> atriplex> prosopis. Prosopis and leucena presented greater (P=0.002) propionate (C3) production with corresponding decrease (P=0.004) in the acetate:propionate ratio (C2/C3). Acacia and leucena showed lower (P=0.0002) NH3-N concentration associated with the decline in protein ruminal degradability. However, leucena showed greater (P<0.001) intestinal protein digestibility than acacia. The objective of the second study was to evaluate in vitro the potential of constituents of essential oils carvacrol (CAR) and eugenol (EUG) at doses of 5, 10 and 20 (CAR) and 10, 20 and 30 (EUG) \'mü\'l/75ml of culture fluid, as a natural alternative to rumen microbial fermentation modifiers compared with monensin (MON) (3 \'mü\'M/75ml of culture fluid) as a positive control. CAR10 and EUG20 showed similarity (P>0.05) in reduction of CH4 emission and OMTD compared with MON, but it had different (P<0.05) short chain fatty acids (SCFA) profile. Monensin increased C3 concentration and decreased C2/C3 ratio, but CAR10 and EUG20 increased (P<0.0001) concentrations of butyrate without effect on the total SCFA. Leucena was selected in the third study to evaluate in vivo the tannins biological activity in total apparent digestibility, nitrogen balance, rumen fermentation and CH4 emission. Six adult rumen cannulated Santa Inês sheep (70±2.5 kg) were individually divided into three experimental diets in a double Latin square design (3 treatments, 3 periods, 6 animals). In the control diet (CNTRL), animals received a basal diet containing Tifton hay (70%), soybean meal (21%) and ground maize (9%). The second diet contained leucena (LEUC), (123 and 8.8 g/kg DM of total tannins and condensed tannins respectively) replacing 50% of Tífton hay. The third diet (LPEG), polyethylene glycol was supplemented at rate of 20g/day/animal. Leucaena-containing diets increased intake of crude protein (P=0.008) and lignin (P<0.001) compared with CNTRL, while there were no significant differences among all diets for the nutrients apparent digestibility except for acid detergent fiber (ADF) was reduced (P=0.0009) by LEUC. Leucaena-containing diet reduced (P<0.001) rumen ammonia concentration and urinary excretion of nitrogen (P=0.0065). Leucena-containing diets decreased (P<0.001) CH4 emission as well as reduced (P<0.001) C2/C3 ratio compared to CNTRL. These studies highlight the potential of tanniniferous plants and the essential oils active components to modulate the rumen fermentation and to reduce CH4 emission in ruminants
Taninos e óleos essenciais são metabólitos secundários que podem ser utilizados como modificadores naturais da fermentação ruminal para reduzir a emissão de metano (CH4) de ruminantes. Para estudar a aplicação de plantas ricas em taninos oriundas do Egito e do Brasil, bem como óelos essencias disponíveis no comércio internacional, três estudos foram conduzidos no Laboratório de Nutrição Animal do Centro de Energia Nuclear na Agricultura da Universidade de São Paulo, Piracicaba. O primeiro estudo teve como objetivo investigar o potencial das plantas taniníferas prosopis (Prosopis juliflora), acácia (Acasia saligna), atriplex (Atriplex halimus) e leucena (Leucaena leucocephala) em ensaio in vitro de produção de gás, avaliando o potencial metanogênico, a degradabilidade ruminal da proteína e a digestibilidade da proteína pós-ruminal, em comparação com feno de Tífton (Cynodon spp.) como alimento sem tanino. O ranking das plantas de acordo com seu potencial de redução de CH4 com base na matéria orgânica verdadeiramente degradada (MODV) foi acácia> leucena> atríplex> prosopis. Prosopis e leucena apresentaram maior (P=0,002) produção de propionato (C3) com diminuição (P=0,004) correspondente na relação acetato:propionato (C2/C3). Acácia e leucena apresentaram menor (P=0,0002) concentração de NH3-N associada com a diminuição na degradabilidade ruminal da proteína. No entanto, a leucena mostrou maior (P<0,0001) digestibilidade da proteína intestinal que a acácia. O objetivo do segundo estudo foi avaliar in vitro o potencial dos óleos essenciais carvacrol (CAR) e eugenol (EUG), nas doses 5, 10 e 20 (CAR) e 10, 20 e 30 (EUG) \'mü\'l/75ml de fluido de cultura, como alternativa de modificadores naturais da fermentação ruminal em comparação com a Monensina (MON) (3 \'mü\'M/75ml de fluido de cultura) como controle positivo. CAR10 e EUG20 apresentaram similaridade na CH4 e MODV comparado com MON, no entanto foram diferentes (P<0.05) no perfil de AGV, onde MON aumentou a concentração de C3 e diminuiu C2/C3, mas ambos CAR10 e EUG20 aumentaram (P<0,0001) as concentrações de butirato. Leucena foi selecionada no terceiro estudo para avaliação in vivo da atividade biológica de taninos na digestibilidade aparente, balanço de nitrogênio, fermentação ruminal e emissão de CH4. Seis ovinos Santa Inês adultos, canulados no rúmen (70±2,5kg) foram individualmente divididos em três dietas experimentais em delineamento quadrado latino duplo (3tratamentos, 3períodos, 6animais). A dieta controle (CNTRL), contendo feno de Tífton (70%), farelo de soja (21%) e milho (9%). A dieta (LEUC), contendo leucena (123 e 8,8g/kg MS taninos totais e taninos condensados, respectivamente), consistiu na dieta controle, tendo 50% do feno de Tífton substituído pela leucena. A dieta LPEG constituiu da dieta LEUC mais a adição de 20g/dia/animal de polietileno glicol (PEG). Dietas contendo leucena aumentaram (P=0,008) a ingestão de proteína bruta, nitrogênio (P=0,005) e lignina (P<0,001) em comparação com CNTRL, enquanto não houve diferenças significativas para as digestibilidades aparentes das nutrientes mas a dieta LEUC diminuiu (P=0,0009) a digestibilidade da fibra em detergente ácido, amônia ruminal (P<0,0001) e excreção urinária de nitrogênio (P=0,0065). Dietas contendo leucena diminuíram (P<0,0001) CH4 bem como diminuíram (P<0,0001) C2/C3 em comparação com CNTRL. Estes estudos destacam o potencial das plantas taniníferas e os óleos essenciais para modular a fermentação ruminal e reduzirem a emissão de CH4
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31

Jouini, Amira. "Herbicidal activity of Mediterranean essential oils and their effects on soil bioindicators". Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/159914.

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[ES] Las preocupaciones ambientales y de salud han estimulado el interés en estrategias alternativas para el manejo de las malas hierbas. En todo el mundo se están haciendo esfuerzos para reducir la gran dependencia de los herbicidas sintéticos que se utilizan como principal método para el control de las plantas arvenses. Los herbicidas naturales basados en sustancias alelopáticas, como los aceites esenciales (AEs) extraídos de plantas, se han sugerido como una de las posibles alternativas para lograr un manejo sostenible de las arvenses. Por un lado, los AEs han mostrado capacidad para inhibir la germinación y el crecimiento de semillas de malas hierbas, por otro lado, hay una falta de estudios sobre los efectos de tales sustancias sobre los microorganismos del suelo. Por lo tanto, en esta tesis se ha investigado la actividad fitotóxica y herbicida de los AEs extraídos de plantas mediterráneas para determinar su potencial como herbicidas naturales. Se han ensayado los efectos de AEs, así como de otros extractos de plantas como hidrolatos, extractos acuosos y hojas frescas obtenidas de plantas mediterráneas, sobre los microorganismos del suelo. Las especies donadoras de AEs fueron seleccionadas en base a conocimientos previos del grupo de investigación, y de acuerdo con la bibliografía existente sobre la actividad herbicida de metabolitos secundarios de estas especies o de especies que están taxonómicamente estrechamente relacionadas: Eucalyptus camaldulensis Dehnh., Eucalyptus occidentalis Endl., Eucalyptus globulus Labill., Eucalyptus torquata Luehm., Eucalyptus lesoufii Maiden, Thymbra capitata (L.) Cav., Mentha × piperita L. y Santolina chamaecyparissus L. Como malas hierbas objetivo se seleccionaron dos monocotiledóneas, Avena fatua L. y Echinochloa crus-galli (L.) P. Beauv. y dos dicotiledóneas, Portulaca oleracea L. y Amaranthus retroflexus L. La composición de los AEs se analizó mediante Cromatografía de gases (CG) y Cromatografía de gases-Espectrometría de masas (CG-EM). Los ensayos in vitro se realizaron en cámaras de germinación, para evaluar los efectos fitotóxicos de los AEs sobre la germinación y el crecimiento de las plántulas. Los ensayos in vivo se realizaron en condiciones de invernadero, los AEs se aplicaron emulsionados con Fitoil mediante riego. El estudio de los efectos sobre los microorganismos del suelo se realizó en el laboratorio en macetas donde los suelos se trataron con los AEs y extractos de hojas y luego se incubaron a temperatura ambiente (20-23 ° C). Los ensayos in vitro revelaron que todos los AEs mostraron efectividad contra las malas hierbas ensayadas. Entre ellos, T. capitata fue el más eficaz. A las dosis más bajas, bloqueó completamente la germinación de todas las semillas. Los ensayos en invernadero demostraron la actividad herbicida de T. capitata, M. piperita y S. chamaecyparissus, aumentando su fitotoxicidad con la dosis. T. capitata fue el AE más eficaz contra todas las malas hierbas a la dosis máxima y P. oleracea fue la especie más resistente. Los microorganismos del suelo, después de un período transitorio de agitación, generalmente recuperaron su función y biomasa iniciales. Solo el AE de T. capitata a la dosis más alta no permitió que los microorganismos del suelo recuperaran completamente su funcionalidad inicial. La aplicación de extractos de hojas al suelo proporcionó evidencia de que las hojas de eucalipto y sus extractos (AE, hidrolatos y extractos acuosos), afectaron a la comunidad microbiana del suelo de diferente modo, dependiéndose de la especie de Eucalyptus considerada. Hasta el momento, los resultados permiten sugerir la aplicación de los Aes como bioherbicidas en entornos controlados y en condiciones de invernadero. Se debe identificar la dosis óptima de aplicación para controlar las malas hierbas y simultáneamente, no afectar negativamente a los microorganismos del suelo.
[CA] Les preocupacions ambientals i de salut han estimulat l'interès per estratègies alternatives de gestió de les males herbes. A tot el món, s'estan fent esforços per reduir la gran dependència dels herbicides sintètics que s'utilitzen com a principal mètode per al control de les males herbes. Els herbicides naturals basats en substàncies al·lelopàtiques, com els olis essencials (OEs) extrets de plantes, s'han suggerit com una de les alternatives possibles per aconseguir una gestió sostenible de les males herbes. Els OEs han mostrat capacitat per inhibir la germinació i el creixement de llavors de males herbes, però per altra banda, falten estudis sobre els efectes d'aquestes substàncies sobre els microorganismes del sòl. En aquesta tesi es van investigar les activitats fitotòxiques i herbicides dels OE extrets d'herbes mediterrànies per a un ús potencial com a herbicides naturals. A més, es van provar els efectes d'aquests OE i d'altres extractes vegetals, com hidrolats, extractes aquosos i fulles fresques obtingudes d'herbes mediterrànies sobre els microorganismes del sòl. Les espècies donants d'OEs es van seleccionar bassant-se en la experiencia previa del grup d'investigació i en la bibliografía existent sobre les activitats biològiques dels metabòlits secundaris d'aquestes espècies: Eucalyptus camaldulensis Dehnh., Eucalyptus occidentalis Endl., Eucalyptus globulus Labill., Eucalyptus torquata Luehm., Eucalyptus lesoufii Maiden, Thymbra capitata (L.) Cav., Mentha × piperita L. i Santolina chamaecyparissus L. Les males herbes objectiu seleccionades van ser dos monocotiledóneas, Avena fatua L. i Echinochloa crus-galli (L.) P. Beauv. i dos dicotiledóneas, Portulaca oleracea L. i Amaranthus retroflexus L. La composició dels OEs es va analitzar mitjançant Cromatografia de gasos (CG) i Cromatografia de gasos-espectrometria de mases (CG-EM). Els assajos in vitro es van realitzar en cambres de germinació per avaluar els efectes dels OEs sobre la germinació i el creixement de les plàntules. Els assajos in vivo es van realitzar en condicions d'hivernacle, on es van aplicar per reg els OEs emulsionats amb Fitoil a les males herbes. L'estudi dels efectes dels OEs sobre els microorganismes del sòl es van realitzar en un experiment en tiestos en condicions de laboratori, en el qual els sòls van ser tractats amb els OEs i els extractes de fulles i després van ser incubats a temperatura ambient (20-23 ° C). Els resultats dels assaigs in vitro van revelar que tots els OE van mostrar efectivitat contra les males herbes objectiu. Entre tots ells, T. capitata va ser el més eficaç. A dosis més baixes, va bloquejar completament la germinació de tots les llavors. Els assaigs en hivernacle van demostrar l'activitat herbicida de T. capitata, M. piperita i S. chamaecyparissus, augmentant la seva fitotoxicitat amb la dosi. T. capitata va ser l'OE més eficaç contra totes les males herbes a la dosi màxima i P. oleracea va ser la mala herba més resistent. Els microorganismes del sòl, després d'un període de trastorn transitori, en general van recuperar la seva funció inicial i la seva biomassa. Només l'oli de T. capitata, a la dosi més alta no va permetre als microorganismes del sòl recuperar completament la seva funcionalitat inicial. Els resultats de l'aplicació d'extractes de fulles al sòl van demostrar que les fulles d'eucaliptus i els seus extractes (OEs, hidrolats i extractes aquosos), afecten la comunitat microbiana del sòl de diferents maneres, depenien de les espècies d'eucaliptus. Fins ara, els resultats obtinguts fan possible suggerir l'aplicació d'EOs com a bioherbicides en entorns controlats com l'horticultura i en condicions d'hivernacle, però s'ha d'identificar la dosi òptima d'aplicació per controlar les males herbes i simultàniament, no afectar negativament els microorganismes del sòl.
[EN] Environmental and health concerns caused for traditional crop protection systems have stimulated interest in alternative weed management strategies. Worldwide, efforts are being made to reduce the heavy reliance on synthetic herbicides that are used to control weeds. Natural herbicides based on allelopathic substances, such as volatile essential oils (EOs) extracted from plants, has been suggested to be one of the possible alternatives for achieving sustainable weed management. From one hand, EOs have shown ability to inhibit weeds seed germination and growth, on the other hand there is a lack of studies about the effects of such substances on soil microorganisms. Therefore, in this thesis the phytotoxic and herbicidal activities of EOs extracted from Mediterranean plants were investigated for their potential use as natural herbicides. The effects of EOs, as well as, of other plant extracts, such as hydrolates, aqueous extracts and fresh leaves obtained from Mediterranean plants, were tested on soil microorganisms. The donor species of EOs were selected based on previous experience of the research group and according to the current literature about the herbicidal activities of the secondary metabolites of these species or from species that are taxonomically closely related: Eucalyptus camaldulensis Dehnh., Eucalyptus occidentalis Endl., Eucalyptus globulus Labill., Eucalyptus torquata Luehm., Eucalyptus lesoufii Maiden, Thymbra capitata (L.) Cav., Mentha × piperita L. and Santolina chamaecyparissus L. The target weeds were two monocotyledons, Avena fatua L. and Echinochloa crus-galli (L.) P. Beauv, and two dicotyledons, Portulaca oleracea L. and Amaranthus retroflexus L. EOs composition was analyzed by means of Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). The in vitro assays were performed in germination chambers, to assess the effects of EOs on weed seed germination and seedling growth. The in vivo trials were conducted in greenhouse conditions, where EOs emulsified by Fitoil were applied on weed species by watering. The study of EOs effects on soil microorganisms was carried out in a laboratory pot experiment, where soils were treated with EOs and leaf extracts and then incubated at room temperature (20-23°C). Results obtained from the in vitro bioassays revealed that all used EOs displayed of effectiveness against assayed weeds, controlling completely their germination process or reducing it and significantly inhibiting their seedling growth. Among them, T. capitata was the most effective. At lower doses, it blocked completely the seed germination of A. retroflexus, P. olecerea, A. fatua and E. crus-galli. Greenhouse trials demonstrated herbicidal activity of T. capitata, M. piperita and S. chamaecyparissus, increasing their phytotoxicity with the dose. T. capitata was the most effective against all weeds at the maximum dose and P. oleracea was the most resistant weed. Soil microorganisms, after a transient upheaval period, induced by the addition of EOs, generally recovered their initial function and biomass. Only T. capitata EO at the highest dose did not allow soil microorganisms to completely recover their initial functionality. Results of leaf extracts application on soil provided evidence that Eucalyptus leaves and their extracts (EOs, hydrolates and aqueous extracts), affected soil microbial community in different ways, and those effects were dependent on the Eucalyptus species. So far, the results obtained make feasible to suggest EOs application as bio-herbicides in controlled environments, such as horticulture and in greenhouse conditions. However, the optimum dose of application must be determined, to control weeds and simultaneously, not negatively affect soil microorganisms.
Jouini, A. (2020). Herbicidal activity of Mediterranean essential oils and their effects on soil bioindicators [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/159914
TESIS
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32

Perdones, Montero Ángela. "ANTIFUNGAL CHITOSAN-BASED FILMS AND COATINGS CONTAINING ESSENTIAL OILS FOR FRUIT APPLICATIONS". Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/59413.

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[EN] Chitosan films and coatings have been obtained, by incorporating different essential oils (EO) and using different homogenization conditions of the film forming emulsions, in order to obtain antifungal materials for fruit preservation. The effect of oleic acid (OA) on the stability of the initial emulsions and on the film properties was analysed. Coatings were applied to control fungal decay in strawberries. The blending of chitosan with methylcellulose (MC) was also used in coating applications to tomato plants and fruits to prevent fungal infections. The films' functional properties as a function of their composition were analysed, as well as their antimicrobial activity through in vitro and in vivo tests. OA incorporation in the chitosan films (1:1 wt. ratio) reduced water vapour permeability (WVP) values to about 50 % of those of net chitosan films, with a small positive effect of the microfluidization process. EO (cinnamon, thyme and basil) did not notably reduced the WVP values of the chitosan films but a significant improvement in water barrier capacity was induced when OA was also added at 1:1 or 1:0.5 CH:OA ratios. In contrast, lipids slightly promoted oxygen permeability of the films. Lipid addition decreased the film stretchability and stiffness, with a lesser impact on the resistance to break, slightly depending on the droplet sizes. Essential oils also modulated the mechanical behaviour of the films, depending on their composition. Thyme and basil EO greatly promoted film stiffness and resistance to break, whereas cinnamon oil slightly reduced these mechanical attributes. Optical properties of the chitosan films were also affected by lipid incorporation. OA reduced the film transparency and gloss depending on the concentration, but provoked small changes in the colour parameters and whiteness index. EO affected transparency to a lesser extent, but had greater impact on the colour coordinates and whiteness index of the chitosan films due to the selective light absorption of their compounds. EO blend with oleic acid mitigated the colour changes in the films. Likewise, blending of OA with EO significantly reduced the losses of volatiles during the film formation due to the promotion of the stability of the film forming emulsions. Films containing cinnamon EO were effective in reducing the growth of Aspergillus niger, Botrytis cinerea and Rhizopus stolonifer, although thyme and basil EO encapsulated in the films did not exhibit antifungal action against these three fungi. When chitosan-cinnamon EO coatings were applied to strawberries inoculated with R. stolonifer, they reduced the fungal decay of the fruits during 14 days, at 10 °C, at the same time that total coliform counts were maintained at the initial levels. Chitosan coatings with lemon essential oil were also active at controlling fungal decay in strawberries. These did not significantly affect the physicochemical parameters of strawberries throughout cold storage, while they slowed down the respiration rate of the fruits and enhanced the chitosan antifungal activity against B. cinerea. The coatings, with and without lemon EO, affected the strawberry volatile profile, although it was only sensory appreciated for samples coated with chitosan-lemon oil. Blend films of CH and MC (1:1) containing oregano EO caused phytotoxic problems at "3 Leaves" stage of tomato plants, although the total biomass and crop yield was not affected. In the "Fruit" stage, the treatments had no negative effects. Coatings reduced the respiration rate of tomatoes, diminished weight loss during postharvest storage and were effective to decrease the fungal decay of tomatoes inoculated with R. stolonifer. Migration of thymol and carvacrol from CH-MC films in food simulants could overcome the stablished specific migration limit (60 mg/kg) for food contact packaging materials in aqueous and low pH systems if films contain a 1:1 polymer essential oil weight ratio.
[ES] En la presente tesis doctoral se han desarrollado diferentes materiales antifúngicos para su uso en conservación de frutas. Para ello, se han incorporado diferentes aceites esenciales (AE) en recubrimientos y películas de quitosano (Q). Se ha analizado el efecto de la adición de ácido oleico (AO) y las condiciones de homogeneización sobre la estabilidad de las emulsiones y sobre las propiedades de las películas. Se ha estudiado el efecto de los recubrimientos de Q sobre el deterioro fúngico en fresas y el efecto preventivo frente a infecciones fúngicas de las mezclas de metilcelulosa (MC) con Q en plantas de tomate. Se ha estudiado el efecto de la composición de las películas sobre las propiedades funcionales de las mismas, así como su actividad antimicrobiana in vitro e in vivo. La incorporación de AO en las películas de Q (proporción 1:1) redujo la permeabilidad al agua (PVA) en un 50% comparado con la de Q puro. La microfluidización indujo un efecto positivo sobre dicha reducción. La adición de AE (hoja de canela, tomillo o albahaca) no supuso una disminución notable de los valores de permeabilidad obtenidos para las películas de Q. Cuando se añadió AO a las formulaciones de Q y AE (proporciones 1:1 o 1:2), se promovió una mejora significativa en la PVA de las películas. En cambio, la adición de lípidos aumentó ligeramente la permeabilidad al oxígeno, disminuyó la elasticidad y la rigidez, y produjo un menor impacto sobre la resistencia a la rotura. A su vez, la adición de AE modificó el comportamiento mecánico de las películas. Los AE de tomillo y albahaca aumentaron considerablemente la rigidez y la resistencia a la rotura, mientras que el AE de hoja de canela redujo estos parámetros ligeramente. La adición de lípidos a las películas de Q afectó las propiedades ópticas de las mismas. El AO redujo la transparencia y el brillo, en función de la concentración añadida. La adición de AE tuvo un mayor impacto sobre los parámetros de color y el índice de blancura. Las mezclas de AE y AO mitigaron estos cambios de color. Además, la incorporación de las mezclas AE-OA redujo las pérdidas de volátiles del AE durante la formación de las películas. Las películas formuladas con el AE de hoja de canela fueron efectivas contra el crecimientos de A. niger, B. cinerea y R. stolonifer, aunque los AE de tomillo y albahaca encapsulados en las películas no mostraron ninguna actividad antifúngica. La aplicación de los diferentes recubrimientos de Q AE de C en fresas inoculadas con R. stolonifer dio lugar a una reducción en el deterioro fúngico de los frutos almacenados durante 14 días a 10°C. Los recubrimientos de Q-AE de limón también fueron efectivos en el control del deterioro fúngico en fresas. Estos recubrimientos no afectaron significativamente los parámetros físico-químicos de las fresas durante el almacenamiento en refrigeración, disminuyeron la tasa de respiración de los frutos y acentuaron la actividad antifúngica del Q frente a B. cinerea. Tanto los recubrimientos con AE como los de Q puro modificaron el perfil de volátiles de las fresas, aunque estos cambios solo fueron apreciados sensorialmente en el caso de los frutos recubiertos con AE. Las mezclas de Q y MC que contenían AE de orégano causaron efectos fitotóxicos en plantas de tomate en el estadio "3 hojas", aunque no afectaron a la biomasa total. En el estadio "frutos" los tratamientos no tuvieron ningún efecto negativo. Los recubrimientos redujeron la tasa de respiración de los tomates, disminuyeron la pérdida de peso durante el almacenamiento post-cosecha y fueron efectivos contra el deterioro fúngico de tomates inoculados con R. stolonifer. La migración de los compuestos fenólicos timol y carvacrol, contenidos en las películas de Q-MC, podría superar el límite de migración específica establecido (60 mg/Kg) para materiales de envase en contacto con alimentos en los casos de sistemas acuosos y d
[CAT] En la present tesi doctoral s'han desenvolupat diferents materials antifúngics per al seu ús en conservació de fruites. Per a açò, s'han incorporat diferents olis essencials (OE) en recobriments i pel·lícules de quitosano (Q). S'ha analitzat l'efecte de l'addició d'àcid oleic (AO) i les condicions d'homogeneïtzació sobre l'estabilitat de les emulsions i sobre les propietats de les pel·lícules obtingudes. S'ha estudiat l'efecte dels recobriments de Q sobre la deterioració fúngica en maduixes i l'efecte preventiu enfront d'infeccions fúngiques de les mescles de metilcelulosa (MC) amb Q en plantes de tomaca. S'ha estudiat l'efecte de la composició de les pel·lícules sobre les propietats funcionals de les mateixes, així com la seua activitat antimicrobiana in vitro i in vivo. La incorporació de AO en les pel·lícules de Q (1:1) va reduir la permeabilitat al vapor d'aigua (PVA) en un 50% comparat amb la de Q pur. La microfluidització va induir un petit efecte positiu sobre aquesta reducció. L'addició de AE (fulla de canyella, C, timó, T, i alfàbrega, A) no va suposar una disminució notable dels valors de permeabilitat obtinguts per a les pel·lícules de Q. Quan es va afegir AO a les formulacions de Q i AE, es va promoure una millora significativa en la PVA de les pel·lícules. Per contra, l'addició de lípids va augmentar lleugerament la permeabilitat a l'oxigen, va disminuir l'elasticitat i la rigidesa, i va produir un menor impacte sobre la resistència al trencament. Al seu torn, l'addició de OE va modificar el comportament mecànic de les pel·lícules. Els OE de T i d'A van augmentar considerablement la rigidesa i la resistència al trencament, mentre que l'OE de C va reduir aquests paràmetres lleugerament. L'addició de lípids a les pel·lícules de Q també va afectar les propietats òptiques de les mateixes. L'AO va reduir la transparència i la lluentor, en funció de la concentració afegida. L'addició d'OE va tenir un major impacte sobre el paràmetres de color i l'índex de blancor. Les mescles d'OE i AO van mitigar aquests canvis de color. A més, la incorporació de les mescles OE-AO va reduir les pèrdues de volàtils de l'OE durant la formació de les pel·lícules. Les pel·lícules formulades amb l'OE de C van ser efectives contra el creixements d'A. niger, B. cinerea i R. stolonifer, encara que els OE de T i A encapsulats en les pel·lícules no van mostrar cap activitat antifúngica. L'aplicació dels diferents recobriments de Q OE de fulla de canyella en maduixes inoculades amb R. stolonifer va donar lloc a una reducció en la deterioració fúngica dels fruits emmagatzemats durant 14 dies a 10°C. Els recobriments de Q-OE de llimó també van ser efectius en el control de la deterioració fúngica en maduixes. Aquests recobriments no van afectar significativament els paràmetres fisicoquímics de les maduixes durant l'emmagatzematge en refrigeració, van disminuir la taxa de respiració dels fruits i van accentuar l'activitat antifúngica del Q enfront de B. cinerea. Tant els recobriments amb OE com els de Q pur van modificar el perfil de volàtils de les maduixes, encara que aquests canvis sol van ser apreciats sensorialment en el cas dels fruits recoberts amb OE. Les mescles de Q:MC que contenien OE d'orenga van causar efectes fitotòxics en plantes de tomaca en l'estadi "3 fulles", encara que no van afectar a la biomassa total. En l'estadi "fruits" els tractaments no van tenir cap efecte negatiu. Els recobriments van reduir la taxa de respiració de les tomaques, van disminuir la pèrdua de pes durant l'emmagatzematge post collita i van ser efectius contra la deterioració fúngica de tomaques inoculades amb R. stolonifer. La migració dels compostos fenòlics timol i carvacrol, continguts en les pel·lícules de Q-MC, podria superar el límit de migració específica establit (60 mg/Kg) per a materials d'envàs en contacte amb aliments en els casos de sistemes aquosos i d
Perdones Montero, Á. (2015). ANTIFUNGAL CHITOSAN-BASED FILMS AND COATINGS CONTAINING ESSENTIAL OILS FOR FRUIT APPLICATIONS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59413
TESIS
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33

JOUINI, AMIRA. "Herbicidal activity of Mediterranean essential oils and their effects on soil bioindicators". Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/434529.

Testo completo
Abstract (sommario):
Environmental and health concerns caused for traditional crop protection systems have stimulated interest in alternative weed management strategies. Worldwide, efforts are being made to reduce the heavy reliance on synthetic herbicides that are used to control weeds. Natural herbicides based on allelopathic substances, such as volatile essential oils (EOs) extracted from plants, has been suggested to be one of the possible alternatives for achieving sustainable weed management. From one hand, EOs have shown ability to inhibit weeds seed germination and growth, on the other hand there is a lack of studies about the effects of such substances on soil microorganisms. Therefore, in this thesis the phytotoxic and herbicidal activities of EOs extracted from Mediterranean plants were investigated for their potential use as natural herbicides in a sustainable weed management context. In addition, the effects of EOs, as well as, of other plant extracts, such as hydrolates, aqueous extracts and fresh leaves obtained from Mediterranean plants, were tested on soil microorganisms. The donor species of EOs were selected based on previous experience of the research group and according to the current literature about the herbicidal activities of the secondary metabolites of these species or from species that are taxonomically closely related: Eucalyptus camaldulensis Dehnh., Eucalyptus occidentalis Endl., Eucalyptus globulus Labill., Eucalyptus torquata Luehm., Eucalyptus lesoufii Maiden, Thymbra capitata (L.) Cav., Mentha × piperita L. and Santolina chamaecyparissus L. The target weeds were two monocotyledons, Avena fatua L. and Echinochloa crus-galli (L.) P. Beauv, and two dicotyledons, Portulaca oleracea L. and Amaranthus retroflexus L., all them important weeds in Mediterranean crops. EOs composition was analyzed by means of Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). The in vitro assays were performed in germination chambers, to assess the effects of EOs on weed seed germination and seedling growth. The in vivo trials were conducted in greenhouse conditions, where EOs emulsified by Fitoil were applied on weed species by watering. Effects on weeds were evaluated by measuring these plant parameters variables: root, aerial parts, and total length of the plants, fresh and dry weight, efficacy of the treatments on each plant, and damage level. The study of EOs effects on soil microorganisms was carried out in a laboratory pot experiment, where soils were treated with EOs and leaf extracts and then incubated at room temperature (20-23°C). Effects on soil microorganisms were measured by determining the main biochemical properties such as microbial biomass carbon and nitrogen, microbial respiration, and the relative abundance of the main microbial groups. Results obtained from the in vitro bioassays revealed that all used EOs displayed of effectiveness against assayed weeds, controlling completely their germination process or reducing it and significantly inhibiting their seedling growth. Among them, T. capitata was the most effective. At lower doses, it blocked completely the seed germination of A. retroflexus, P. olecerea, A. fatua and E. crus-galli. Greenhouse trials demonstrated herbicidal activity of T. capitata, M. piperita and S. chamaecyparissus, increasing their phytotoxicity with the dose. T. capitata was the most effective against all weeds at the maximum dose and P. oleracea was the most resistant weed. Soil microorganisms, after a transient upheaval period, induced by the addition of EOs, generally recovered their initial function and biomass. Only T. capitata EO at the highest dose did not allow soil microorganisms to completely recover their initial functionality. Results of leaf extracts application on soil provided evidence that Eucalyptus leaves and their extracts (EOs, hydrolates and aqueous extracts), affected soil microbial community in different ways, and those effects were dependent on the Eucalyptus species. So far, the results obtained make feasible to suggest EOs application as bio-herbicides in controlled environments, such as horticulture and in greenhouse conditions. However, the optimum dose of application must be determined, to control weeds and simultaneously, not negatively affect soil microorganisms. Nonetheless, further field research is necessary to completely understand the potential of EOs in field conditions, and it is required to develop an appropriate formulation to improve the persistence and penetrability of EOs and so increase their capacity to control weeds.
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Ishlak, Adel. "ALTERING THE FORMATION OF TRANS FATTY ACIDS IN CONTINUOUS CULTURES THROUGH OILS AND NATURAL DIETARY SUPPLEMENTATIONS". OpenSIUC, 2013. https://opensiuc.lib.siu.edu/dissertations/711.

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35

Makgwane, Peter Ramashadi. "Characterization of essential oils by comprehensively coupled supercritical fluid and gas chromatography (SFGxGC)". Pretoria ; [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-02222007-184250.

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36

Lee, Pei-Hua, e 李沛鏵. "The Correlations between Aromatherapy Essential Oils and the Meridians with focus on Labiatae Essential Oils". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/12854751606276544735.

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Abstract (sommario):
碩士
臺北城市科技大學
運動健康與休閒所
101
The Correlations between Aromatherapy Essential Oils and the Meridians with focus on Labiatae Essential Oils Abstract There are many theories on how the essential oils affect the human meridians, without consistent empirical proofs. Therefore, this research uses consistent methods to assess the effects of Labiatae essential oils on the meridians. Eight species: thyme, clary sage, rosemary, marjoram, patchouli, spearmint, lavender, and basil, were used as the Labiatae essential oils in the experiment. The research was conducted on 80 voluntary subjects measured with the Ryodoraku. The measurements were collected from 24 specific points on the hands and feet of the subjects, with 5% of the 8 Labiatae essential oils, before the application, 15 minutes after the application, and 30 minutes after the application. The data collected were then analyzed by SPSS ver. 18.0 software for the results. The results show that after the Labiatae essential oils enter the body, there were various effects on the autonomic nervous system, left and right musculoskeletal ratio, and body energy. Thyme, clary sage, rosemary, spearmint, lavender, and basil have the most significant effects on balancing the autonomic nervous system. On the effects of the meridian energy, thyme and patchouli has the most significant effects. Thyme essential oil mainly affects the Gallbladder Meridian, the Large Intestine Meridian, and the Stomach Meridian, while the patchouli affects the Sanjiao Meridian and the Bladder Meridian. The Pearson Correlation Test shows that applications of clary sage, marjoram, and lavender essential oils improve the correlations of the 12 meridians. Keywords : Labiatae essential oils, Meridians, Ryodoraku.
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37

Chun, Chen-Yen, e 陳燕君. "The Correlations between Essential Oils and Meridians with Focus on the Rutaceae Essential Oil". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/53053174080335333888.

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Abstract (sommario):
碩士
臺北城市科技大學
運動健康與休閒所
101
This research established the proof between the Rutaceae essential oil and human meridians. The research is conducted with consistent empirical methods on 70 subjects for data collection. The resulting analysis shows that there are significant correlations between the Rutaceae essential oils and the 12 human meridians. The experiment used 7 essential oils from the Rutaceae family of bergamot, mandarin, sweet orange, petitgrain, lemon, lime, and grape fruit. Ryodoraku machine is used to measure the values of subjects’ 12 meridians before the applications of 5% diluted essential oils, 15 minutes, and 30 minutes after the applications. The collected statistics are then analyzed with SPSS 18.0 for the descriptive analysis, the T-test, and the Pearson’s test. The results show that Rutaceae essential oils are correlated to the five human systems of body energy, upper and lower qi/blood ratios, symmetrical muscle and bone ratios, metabolism, and autonomic nervous systems, and the energy of the 12 meridians. The effects vary depend on the essential oils applied. Rutaceae essential oils have the most significant effects on the upper and lower qi/blood ratios and the balance of autonomic nervous systems. Of the effects of the human meridian energy, Mandarin essential oils have the most effects, on the Small Intestine Meridian, the Spleen Meridian, the Bladder Meridian, the Sanjiao Meridian, the Heart Meridian, and the Pericardium Meridian. The Petitgrain essential oils have the second most effects. While there are variations of the effects of Rutaceae essential oils on the human meridians, the values show significant effects. Sweet orange essential oil has the highest correlation on the whole, with mandarin essential oil second and Petitgrain essential oil the third. Key words: Rutaceae essential oils, meridians, Ryodoraku machine
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38

SHEN, LI-YAN, e 沈立言. "STUDIES ON MICROCAPSULES OF ESSENTIAL OILS". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/82177093976608686077.

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Abstract (sommario):
博士
國立中興大學
食品科技研究所
79
Basil, garlic, and ginger essential oil were extracted by steam distillation, and analyzed by GC and GC-ms. The major components of basil essential oil were methyl chavicol (about 86%) and 1, 8-cineole (6%); those of garlic essential oil were diallyl disulfide (39%) and diallyl trisulfide (31%) etc.; and those of ginger essential oil were camphene (16%) and geranial (19%) etc.. In terms of charater-impact compounds, methyl chavicol which gave fragrance, sweet, fresh, and minty, and 1-octen-3-o1 which gave unpleasant strongly green odor existed in the basil essential oil. Diallyl disulfide which gave strongly pungent garlic-like aroma existed in the garlic essential oil. Neral which gave fragrance, sweet, fresh, cooling, and woody aroma, and those of genarial and beta-sesquiphellandrene + ar-curcumene + genaryl acetate which gave pungent and warm odor existed in the ginger essential oil. In addition, six different kinds of basil essential oils were analyzed by sensory evaluation and gaschromatography. Furthermore, the data were calculated by SAS stepwise regression method trying to find a regression equation which could be used as an estimation for the quality of basil essential oil. Microcapsules of basil, garlic, and ginger essential oil were prepared by spray drying. Changes of components of essential oils during spray-drying process were found. For instance, among the percentage compositions of basil essential oil methyl chayicol etc. tended to decrease, while linalool and 1, 8-cineole etc. increasing. In garlic essential oil, the percentage compositions of diallyl sulfide, methyl allyl disulfide, diallyl disulfide, and 2-vinyl-4H-1, 3-dithiin tended to decrease, while methyl allyl trisulfide and diallyl trisulfide increasing. In ginger essential oil, the percentage compositions of alphapinene, camphene, myrcene, limonene, beta-phellandrene, and geranial tended to decrease, while 1, 8-cineole, 2-heptanol + 6-methyl-5-hepten-2-one, linalool and zingiberene increasing. In respect of the properties of microcapsules which added amounts of core materials were different, the oil retentions decreased with increasing the added amounts of core materials, and the amounts of surface oil were about 0.4-1.7% of oil retentions. The particle size and flowability of microcapusles increased with increasing the added amounts of core materials, and there were no significantly difference for the surface structures of micro-capsules. On the other hand, changes of essential oils fo microcapsules which were stored for one year at room temperature were also investigated. The results of gaschromatography and sensory evaluation showed that the gtarlic essential oil was the most stable followed by basil and ginger essential oil, respectively. Corn and waxy maize native starches were modified by acetylation or phosphation. The high and low degree of substitutions (D.S.) for acetylations were around 0.14-0.18 and 0.5-0.54, respectively; while those for phosphations were about 0.01 and 0.12, respectively. The structures of native starches were damaged during the modifications, the higher degree of modification the more damage was. The starch damage of high D.S. of phosphation, especially high, was about 55-62%, The gelatini- zation temperature and enthalphy of modified starches lowered 15-18 0c and 3-12 j/g starch, respectively, compared with native starches. The modified starches of high D.S. of phosphation even formed cold water soluble starches. Generally, the emulsufying properties, which are important to the preparation of microcapsules, of modified starches mentioned above were better than those of native starches. The properties of microcapusles, which prepared from using corn and waxy maize native and modified starches stated above as carriers and basil essential oil as core material, were studied. The oil retentions were around 90% when corn modified starch of high D.S. of phosphation and waxy maize modified starches of low D.S. of acetylation and phosphation were used as carriers. The surface oils were around 0.22-0.58% of oil retentions. The effects of substituted groups on the percentage compositions of basil essential oil of microcapsules were also investigated. For example, there were higher percentage compositions of esters and 1, 8-cineole in basil essential oil when using acetylated modified starches as carrier. In respect of surface structure of micro- capsules, different carrier had its own characteristics according to the results from SEM. For instance, corn native starch as carrier gave deeply dent but smooth surface structure similar to those of phosphated modified starches. However, waxy maize native starch as carrier gave slightly dent and more crinkly surface structure similar to those of acetylated modified starches. In order to improve the flowability and dissolution ability of spray-dried microcapsules, agglomerated microcapsules were prepared by combination of spray drying and agglomeration techniques using different concentrations of flycerol aqueous solutions as binding agent. According to the results, the optimum concentration of binding agent was 30%. This level gave the agglomerated microcapsules outstanding dissolution ability in water compared to that of the control. The average particle size was 2-3 times as large in the agglomerated sample greater than that of the control. Also the flow rate of the sample was 130 times than that of the control. 以水蒸氣餾法分別萃取羅勒、蒜、薑之精油,經由氣相層析儀與氣相層析儀一質譜儀 之分析鑑定,得知羅勒精油之主成分為methyl chavicol ( 約86%) 與1,8-ci-meole ( 約6%);蒜精油為diallyl disulfide(約39%),deallyl trisulfide( 約31%) 等;而薑精油則為camphene(約16%),geramial( 約19%) 等。至於在精油成分之味道貢獻方面,羅勒精油中,methyl cha-vicol與1- octen-3-o1均為特徵化合物,methyl cha-vicol帶有香味,甜味,清涼薄荷味等好的 羅勒味道,而l-octen-3-o1則賦予令人不悅的青草味,惟此一成分僅在於羅勒梗精油 中含量較多,因此對於整株羅勒精油的味道並不會產生太大的影響;在蒜精油中,以 diallyl di-sulfide對於香味貢獻最大,具有非常強的蒜刺鼻味;在薑精油中,則以 neral,g eranial,beta-sesquiphel-landrene+ar-curcumene +geranyl acetate 等成分對 於香味最有頁獻,neral 具有香味,甜味,清涼味與木材味等,而geranial與beta-s esquiphellandrene +ar-curcumene+geranyl acetate 具有刺鼻與溫暖的味道。另 外,就羅勒精油之品質而言,採用品評與氣相層析之分析方法,針對六種不同植體部 位與不同處理之精油進行研究,並配合逐步迴歸之統計方法,求得一條迴歸方程式, 用以作為羅勒精油品管的標準. 以噴霧乾燥法製備羅勒,蒜,薑精油徵膠囊,發現在噴霧乾燥過程中有精油成分變化 的現象。例如羅勒精油成分百分組成中之methyl chavicol 等則有增加的傾向;蒜精 油成分中diallyl sulfide ,methyl allyl disulfide,diallyl disulfide,2-vinyl-4H-1,3-dithiin等減少,而methyl allyl trisulfide 與diallyl trisulfide增加;薑精油中之alpha-phellandrene,camphene,myrcene,limoneme ,beta-phellandrene,geranial等減少,而1,8-cineole,2-heptanol +6-methyl-5-hepten-2-one,linalool,zingiberene等增加。至於在各種不同精油 添加量之微膠囊性狀方面,微膠囊之精油保留率隨精油添加量增加而降低,而表面油 為保留量之0.4∼1.7%左右。微膠囊之粒度與流動性則隨著精油添加量之增加而增加 ,但不同精油添加量之微膠囊之表面構造並無顯著性差異。另外,精油微膠囊在室溫 下貯藏一年後,其精油成分有所變化,由氣相層析與品評結果顯示,蒜精油成分變化 最小,羅勒精油次之,而以薑精油變化最大. 將天然玉米與糯玉米澱粉以醋酸或磷酸修飾後,醋酸低、高取代度則分別為0.14與∼ 0.54左右,而磷酸低、高取代度則分別為0.01與0.1∼0.12左右。經過修飾之澱粉, 其天然澱粉結構遭受破壞,隨著修飾程度愈高,破壞度愈大,尤以磷酸高取代修飾澱 粉之破壞率更高達55∼62%左右;糊化溫度與糊化所需熱能則分別下降15∼18℃與3 ∼12焦耳/克澱粉,甚至形成冷水可溶澱粉。一般而言,醋酸或磷酸修飾澱粉之乳化 性質較天然者為佳,而此等性質對於微膠囊之製備相當重要. 以玉米、糯玉米之天然及醋酸與磷酸修飾澱粉進行羅勒精油微膠囊之製備。精油保留 量以玉米磷酸高取代修飾澱粉,糯玉米醋酸低取代與磷酸代取代修飾澱粉為膠囊壁物 質時較佳,約為90%左右;而表面油一般為保留量之0.22∼0.58%左右。由各種膠囊 壁中之羅勒精油組成結果可以發現,膠囊壁物質之取代基不同,其所保留之精油組成 亦有所差異。例如以醋酸修飾澱粉為膠囊壁物質時,其所保留之精油成分組成中,以 酯類與1,8-cineole 之量較高。至於在微膠囊之表面構造方面,結果顯示各種不同膠 囊壁物質所製得之微膠囊,其表面構造各具特色。例如玉米天然澱粉者具有凹陷而光 滑的表面特徵,與磷酸修飾澱粉者較為相似;而糯玉米天然澱粉者,其表面凹陷較淺 ,呈現出皺折較多的特徵,與醋酸修飾澱粉者較為相似. 為了改進噴霧乾燥精油微膠囊之流動性與速溶性,以不同濃度之甘油水溶液作為黏著 劑,採用造粒技術配合噴霧乾燥技術,製備造粒微膠囊。結果顯示以30%甘油水溶液 為黏著劑時之造粒微膠囊具有最佳性狀,其表現出優越的溶出速率,而平均粒徑是對 照組的2∼3倍,且流動速率是對照組的130倍.
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39

Karra, Eirini. "Aromatherapy and its favourite essential oils". Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-306571.

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Abstract (sommario):
AROMATHERAPY AND ITS FAVOURITE ESSENTIAL OILS Student: Karra, E. Tutor: Marešová, H. Department of Social and Clinical Pharmacy, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Czech Republic Background: This thesis was made because I wanted to work on something different from what we are being taught at the Faculty of Pharmacy. But the topic should be near to the worlwide pharmacy practice. Nowadays many people are interested in Complementarey and Alternative Medicine (CAM). I decided to visit Dr. Marešová (a teaching practitioner at our Faculty) to ask her for a topic. She agreed and proposed Aromatherapy, and I found it quite interesting. During my work I started to realize how important and effective Aromatherapy may be, how easily it can be applied and become a part of our life. Aim: The aim of the thesis is to gain an understanding of what aromatherapy is and to show its benefits. Furthermore to introduce the substances (essential oils) that can be used and their availability, their several application forms and the various therapeutic effects. Nevertheless, essential oils may also be dangerous sometimes. For example, during pregnancy the use of some essential oils may be a problem and some oversensitive people may see an exacerbation of their allergies as well. Therefore,...
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40

Chin-Hsuan, Chang, e 張雂媗. "Natural essential oils as preservatives in cosmetics". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/4ty89z.

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Abstract (sommario):
碩士
嘉南藥理大學
化粧品應用與管理系
102
This study from 19 kinds of essential oils antibacterial effects of werescreened, based on synergistic combinations of different essential oils, determine the appropriate combination of essential oils antimicrobial agent formulations,And microbiological testing of cosmetics preservative systems impact assessment, as well as product stability testing irritation and further evaluation. Use of paper disk-diffusion method on 19 kinds of essential oils and four commercially available, for detection of the inhibitory activity of Escherichia coli .The results showed that most of the essential oil is a clear zone of inhibition of essential oils A, B, C, D, E, F; Four kinds of commercially available natural antibacterial agent a,b,c,d, where a has only inhibit antimicrobial efficacy. After screened by inhibit efficacy of essential oils and essential oils with different concentrations of a combination of two or more, the other hand also combination of essential oils with antibacterial agents a, use of paper disk-diffusion method screened essential oils in combination with a synergistic effect, the results showed that A, D, E and essential oils commercially available natural antibacterial agent a combination shown to have synergistic effects.10, 40, and 70 fold dilution to be minimum inhibitory concentration(MIC)measured, The results showed that three formulations for E. coli, are presented inhibit the effectiveness. Based on E. coli, P.aeruginosa, S.aureus, yeast and environmental bacteria (space colony bacteria) five kinds of bacteria inhibition test,the proportion natural essential oils antimicrobial formulations of concentration of 0.50% as the use of the added to the three kinds of cosmetic product formulations for toner, serum mask and Cleaning solution, the results confirm natural essential oils antibacterial agent in products for five kinds of bacteria are inhibited.on the other hand skin irritation test, patch test 30 minutes after no confirmed erythema and allergic reactions, While the stability of the product on the exterior color and odor are no significant differences. According to the study results confirm that natural essential oils antibacterial agent added at a concentration of 0.50% is inhibiting the use of performance.In the future will be used in cosmetic product formulations of preservative and having to replace property value.
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41

Lin, Pei-Ju, e 林佩儒. "The applications of essential oils on mending acnecondition". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/99999341515534568983.

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Abstract (sommario):
碩士
嘉南藥理科技大學
化妝品科技研究所
94
Propionibacterium acnes (P. acnes) is one of the factors of acne. P. acnes increase by several orders of magnitude in the environment created by abnormally keratinization in the sebaceous follicle. The organism produces a variety of exocellulan enzymes and molecules with chemoattractant activity, and it has also been shown to stimulate cells of nonspeafic immune system to produce proinflammatory cytokines which initiate inflammation. Antibiotics have been widely used to treat the acne in the part. This resulted in the development of bacterial resistance. Finding new antibiotic components has become the main purpose in the research of anti-acne. Essential oils have been applied for many years in different areas, such as the improvement of air quality, treatment of the disease of respiratory system and, headache, cosmetology and antibiotic. Based on the antibiotic characteriseic of essential oil, the aim of the research was to estimate the potential of essential oils on mending acne condition. The experiment was divided into two parts. Firstly, we sieved out the essential oils which exhibited antibiotic properties and found that nine of them can inhibit the growth of P. acnes, especially Melaleuca cajuputil with minimum inhibitory concentration of 0.01% by broth dilution method. Secondly, we estimate the activity of anti-inflammation of essential oils according to the amounts of IL-8、IL-1β and TNF-?secreted from human monocyte cell line (THP-1) by ELISA method. It was found that the essential oil and the water- soluble components from Eucalyptus citriodora can inhibit the secretion of IL-8 from THP-1 cell induced by LPS and P. acnes suspension. The essential oils and the water-soluble components of Melaleuca alternifolia can inhibit the secretion of IL-1β from THP-1 cell induced by LPS. The essential oils and the water-soluble components of Pelargonium and Melaleuca alternifolia can inhibit the secretion of TNF-?from THP-1 cell induced by III LPS. The essential oil and the water-soluble components of Eucalypus can inhibit the secretion of IL-1β induced by P. acnes suspension. In summary nine essential oils in this study had antimicrobial activity against P. acnes at low concentration. In addition, some of them showed the ability of anti-inflammation. Therefore, these essential oils in this study are potential to be formulated in skin cane products of mending acne. Keywords:Acne、Propionibacterium acnes、Essential oil、Minimum inhibitory concentration、Anti-inflammation
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42

CHEN, CHIU-WAN, e 陳秋婉. "Essential Oils Industry-A Company Management Strategy Analysis". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/drv5e7.

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Abstract (sommario):
碩士
國立雲林科技大學
企業管理系
104
The Taiwan's essential oil products market development and the industry competition is rapidly increasing. The competitive strategy is important to manage the essential oil industry. Cosmetics industry has low entry barriers, low investment in R&D, high value-added and unlimited business opportunities. The previous researches were mostly focused on cosmetics. However, the relevant research on essential oil products industry is rather lacking. Therefore, the research is worth studying. The purpose of this study is to discuss the subject of essential oil industry shown as below: the environment and current situation, the main factors of influencing the competitive strategy and competitive strategy analysis. Therefore, this research has adopted case study to explore A company, and analyze the current operating conditions of essential oil industry in Taiwan by secondary data collection. Finally, the research provides recommendations toward business development strategy for Taiwan's essential oil industry through strategy analysis. Keyword: Essential oils industry, Case study, Strategy analysis
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43

Sousa, Rose Marie Oliveira Ferreira de. "Plant-based pesticides: Potential of apiaceae essential oils". Doctoral thesis, 2016. http://hdl.handle.net/1822/44970.

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Abstract (sommario):
Tese de Doutoramento em Ciências - Especialidade em Biologia
The development of biopesticides follows a strong rising trend over the last two decades, and a continued growth of the global biopesticides market is forecasted. This phenomenon is largely supported by the growing awareness to environmentally friendly food production and the introduction of restrictive regulations for pesticides. In light of their multiples advantage over synthetic pesticides, biopesticides appear economical, eco-friendly and less prone to the development of resistance, and hence are expected to provide more environmentally sustainable methods of biocontrol (Czaja et al., 2015). In fact, biopesticides have been integrated in several pest and vector management programs. As a complementary approach or alternative to synthetic pesticides, phytochemicals, namely essential oils (EOs) and volatile compounds are incorporated into crop protection products, as well as repellent formulations (Regnault- Roger et al., 2012). The best market opportunities have been assigned to EO-based pesticides, owing to the great availability, GRAS status, chemical simplicity, relatively low toxicity to vertebrates and specific mode-of-action of their constituents (Isman & Akhtar, 2007; Shaaya & Rafaeli, 2007). In this context, the Apiaceae (=Umbelliferae) family, which comprised economically important plants species, presents a wide variety of bioactive compounds being also an important source of EOs and volatile compounds distributed by several distinct chemicals classes. Aware of their traditional use, their relatively large worldwide production and the bioactive potential described by many authors, we proposed to perform an appraisal of the biopesticidal potential of well-known Apiaceae species, whose experimental approach, results and discussion are here reported. In a few words, this work consisted in: (1) the characterization of EOs extracted from different plant parts of four species [Anethum graveolens (dill), Cuminum cyminum (cumin), Foeniculum vulgare var. vulgare (bitter fennel), Petroselinum crispum (plain leaf parsley)] and (2) the toxicological evaluation of some EOs and individual constituents, using as target organisms a mosquito (Anopheles atroparvus), a lepidopteran (Pseudaletia unipuncta) and a freshwater snail (Radix peregra). The anti-nematode properties of bitter fennel EOs and two phenylpropanoids against Meloidogyne javanica was also evaluated. EOs were isolated by hydrodistillation and chemically characterized by GC and GC-MS. Quantitative data were obtained using GC-FID and the identification of constituents was achieved with the help of spectra libraries and determination of their KI. The overall identification of their content ranged between 88 and 99.5%. The EOs content (ranging between 0.10-3.45%) and chemical profiles were highly variable depending of the organ type, developmental stage and origin of the material. The development of dill umbels from the pre-flowering to the ripe fruit stage was accompanied by a significant increase of (S)- carvone (from 4 to 61% of the EO content) and a reduction of α-phellandrene and dill ether contents. Bitter fennel infrutescences and leaves plus stems EOs were mainly composed by estragole (64 and 28%, respectively), followed by α-phellandrene, α-pinene and fenchone. We also identified intra-individual variations in the cultivated population of bitter fennel. Concerning cumin EOs, all fruit samples and the commercial EO were mainly constituted by cuminaldehyde (28-39 %), followed by variable amounts of pmentha- 1,4-dien-7-al, p-mentha-1,3-dien-7-al, β-pinene, p-cymene and γ-terpinene. EOs from parsley were the most complex of the four species, being characterized by a high percentage of hydrocarbon monoterpenes and several phenylpropenes (myristicin, apiole, elemicin and/or allyltetramethoxybenzene). The activity of EOs and individual compounds was assessed against A. atroparvus (3rd instar larvae), P. unipuncta (eggs and larvae) and R. peregra (eggs, juveniles and adults). Bitter fennel EOs were also tested against eggs and juveniles of M. javanica. Whenever possible, mortality (%) was recorded for a range of optimized concentrations or at different times of exposure, and the lethal parameters for 50 % and 90% (lethal concentrations, LCs, and/or lethal times, LTs) were estimated by Log-Probit analysis. EOs from parsley, cumin and bitter fennel (leaves more stems) were highly active towards the snail (both eggs and adults) and the mosquito larvae. Estimated LC50 against adult snails varied from 13.7 to 46.5 mg L-1 (48 h), and from 16 to 143 mg L-1 (24 h) against the mosquito larvae, with parsley fruit EO being the most doseeffective one in both situations. A short-time exposure (8 h) to bitter fennel EOs was also effective for snail control. Regarding assays performed on P. unipuncta, dill, cumin and parsley EOs, as well as the compounds (S)-carvone, cuminaldehyde and myristicin, showed satisfactory egg hatching inhibition, and acute contact toxicity to the 4th instar larvae (24 h-LC50 ranging from 108 to 197 μg cm-2). Dill, cumin and bitter fennel EOs and some of their constituents were effective by fumigation (≥80%). In addition, the EO from parsley fruits, trans-anethole and cuminaldehyde displayed significant feeding deterrence and growth inhibition (FDI and GI >70%), when performing the no-choice assay with treated corn leaves, causing significant negative impact on the metabolism of this lepidopteran. Parsley fruits EO was of great efficacy against P. unipuncta, acting as ovicide, larvicide (by contact), feeding deterrent and growth inhibitor. Its constituents myristicin and apiole (purified by CC) showed similar effectiveness in several assays. Besides, we distinguish the phenylpropanoid trans-anethole (a constituent of bitter fennel EOs) for its acute insecticidal, nematicidal and molluscicidal activities, being more active than its isomer (estragole). The present study demonstrates that EOs from the four studied Apiaceae species, along with some of their major compounds, have moderate to strong anti-insect and molluscicidal properties. EOs and compounds showed distinct performances depending on the type of assay, the exposure period, the tested organism and/or its developmental stage. In general, the reproductive organs (umbels-bearing fruits and eventually ripen fruits) were optimum sources of EOs containing the highest percentage of biologically active compounds (except bitter fennel). As a whole, the results demonstrates that the four plant species are promising sources of botanical biopesticides in the context of the biochemical control of phytophagous insects and vectors of human and animal diseases.
O desenvolvimento de biopesticidas tem progredido consistentemente ao longo das duas últimas décadas e as previsões apontam para uma tendência de crescimento contínuo do mercado global destes produtos. Este fenômeno é explicado essencialmente por uma maior consciencialização para a produção de alimentos de um modo sustentável e pela introdução de regulamentações mais restritivas ao uso de pesticidas. Em virtude das suas múltiplas vantagens relativamente aos pesticidas sintéticos, os biopesticidas afiguram-se económicos, ecológicos e menos propensos ao desenvolvimento de resistências constituindo, portanto, métodos de biocontrolo ambientalmente mais sustentáveis (Czaja et al, 2015). Com efeito, os biopesticidas têm sido integrados em vários programas de gestão de pragas e vetores. Como abordagem complementar ou alternativa aos pesticidas sintéticos, os fitoquímicos, nomeadamente óleos essenciais (OE) e seus constituintes voláteis, são incorporados em produtos de proteção das culturas bem como em formulações repelentes (Shaaya & Rafaeli, 2007; Regnault-Roger et al, 2012). Existe uma grande oportunidade de mercado para os pesticidas à base de OEs ou seus constituintes, em virtude da sua grande disponibilidade, da sua classificação GRAS, da simplicidade estrutural das moléculas, da relativa baixa toxicidade para os vertebrados e modos de ação específicos (Isman & Akhtar, 2007; Shaaya & Rafaeli, 2007). Neste contexto, a família Apiaceae (= Umbelliferae), que compreende espécies de plantas economicamente importantes, apresenta uma ampla variedade de compostos bioativos, sendo ainda uma importante fonte de OEs e compostos voláteis pertencentes a diversas classes químicas. Com fundamento nas suas utilizações tradicionais, na importante produção mundial e no potencial bioativo descrito por muitos autores, propusemos realizar uma avaliação do potencial biopesticida de espécies de Apiaceae bem conhecidas. Em resumo, este trabalho consistiu na: (1) caracterização dos OEs de diferentes partes de planta de quatro espécies [Anethum graveolens (aneto), Cuminum cyminum (cominho), Foeniculum vulgare var. vulgare (funcho amargo), Petroselinum crispum (salsa)] e (2) na avaliação toxicológica de alguns OEs, bem como de alguns constituintes, usando uma espécie de mosquito (Anopheles atroparvus), um lepidóptero (Pseudaletia unipuncta) e um caracol de água doce (Radix peregra) como organismos alvo. As propriedades anti-nemátode dos OEs de funcho amargo e dois fenilpropanoides contra Meloidogyne javanica foram igualmente avaliadas. Os OEs foram isolados por hidrodestilação e caracterizados quimicamente por GC e GC-MS. Os dados quantitativos foram obtidos através de GC-FID sendo a identificação dos constituintes concretizada com base na consulta de bibliotecas espectrais e na determinação dos KI. A identificação abrangeu 88 a 99,5% do conteúdo total. Os teores em OE (compreendidos entre 0,10 a 3,45% w/w) e os perfis químicos variaram consideravelmente em função do órgão, do estágio de desenvolvimento e da origem do material. O desenvolvimento de inflorescências de aneto desde a prefloração à maturação dos frutos foi acompanhado por um aumento significativo de (S)-carvona (de 4 a 61% do teor dos OEs) e uma redução dos teores de α-felandreno e anetofurano. Por seu lado, os OEs de infrutescências e caules do funcho amargo eram maioritariamente constituídos por estragole (64 e 28%, respetivamente), seguida de α-felandreno, α-pineno e fenchona. Também identificamos a ocorrência de variações intra-individuais na população cultivada de funcho amargo. Em relação aos OEs do cominho, todas as amostras de frutos e o OE comercial foram maioritariamente constituídos por cuminaldeído (28-39%), e quantidades variáveis de p-menta-1,4-dien-7-al, p-menta-1,3-dien-7-al, β-pineno, pcimeno e γ-terpineno. De entre as quatro espécies os OEs de salsa foram os mais complexos, sendo caracterizados por uma elevada percentagem de hidrocarbonetos monoterpénicos e vários fenilpropenos (miristicina, apiole, elemicina e/ou alil-tetrametoxibenzeno). Posteriormente, foi investigada a atividade dos OEs e alguns compostos individuais sobre A. atroparvus (larvas de terceiro ínstar), P. unipuncta (ovos e larvas) e R. peregra (ovos, jovens e adultos). Os OEs do funcho amargo foram ainda testados contra ovos e jovens de M. javanica. Sempre que possível, a mortalidade (%) foi registrada para uma gama de concentrações otimizadas ou em diferentes tempos de exposição, sendo os parâmetros letais para 50% e 90% (concentrações letais, CLs e/ou tempos letais, TLs) estimadas por análise Log-Probit. Os OEs de salsa, cominho e funcho amargo (folhas e caules) foram extremamente ativos contra as formas embrionária e adulta do caracol, assim como nas larvas de mosquito. As CL50 estimadas para os caracóis adultos variaram entre 13,7 a 46,5 mg L-1 (48 h), e entre 16 a 143 mg L-1 par as larvas do mosquito, sendo evidenciada a maior eficácia do OE de frutos de salsa na dose-resposta, contras ambos os organismos. A exposição de curta duração (8 h) aos OEs do funcho amargo foi também eficaz no controlo dos caracóis. Nos ensaios realizado com P. unipuncta, os OEs de aneto, cominho e salsa, bem como os compostos (S)-carvona, cuminaldeído e miristicina mostraram acentuados efeitos inibitórios na eclosão dos ovos, e uma aguda toxicidade por contacto sobre as larvas no quarto instar (as CL50 às 24 h variaram entre 108 a 197 μg cm-2). Os OEs de aneto, cominho e funcho e alguns dos seus constituintes foram eficazes por fumigação (≥80%). Além disso, o OE de frutos de salsa, o trans-anetole e o cuminaldeído apresentaram efeitos inibitórios agudos no consumo de folhas de milho tratadas e no crescimento das larvas (FDI e GI> 70%), revelando um impacto negativo no metabolismo deste lepidóptero muito significativo. O OE dos frutos da salsa foi de grande eficácia ovicida, larvicida, fago-repelente, e inibidor do crescimento larvar. Os constituintes miristicina e apiole, ambos purificados do OE de frutos de salsa por CC, mostraram eficácia similar em alguns ensaios. Além disso, distinguimos o phenylpropanoid trans-anetole (constituinte do OE de funcho) pela sua forte atividade inseticida, nematicida e moluscicidas, sendo mais ativo que o seu isómero (estragole). O presente estudo demonstra que os OEs das quatro espécies de Apiaceae, e alguns dos compostos testados, apresentam propriedades anti-inseto e moluscicidas moderadas a elevadas. Os OEs e compostos apresentaram desempenhos distintos, dependendo do tipo de ensaio, do período de exposição, do organismo testado e/ ou do seu estágio de desenvolvimento. Em geral, os órgãos reprodutivos destas plantas (infrutescências, eventualmente frutos maduros) foram ótimas fontes de OEs contendo percentagens superiores de compostos biologicamente ativos (exceto o funcho amargo). No seu todo, os resultados demonstram que as quatro espécies de plantas são promissoras fontes de biopesticidas botânicos no contexto do controlo bioquímico de insetos fitófagos e vetores transmissores de doenças em humanos e animais.
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44

(8703072), Sudip Gaire. "TOXICOLOGY OF PLANT ESSENTIAL OILS IN BED BUGS". Thesis, 2020.

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Abstract (sommario):

Bed bugs (Cimex lectularius L.) are globally important human ectoparasites. Their management necessitates the use of multiple control techniques. Plant-derived essential oils are extracts from aromatic plants that represent one of the alternative control measures for bed bug control, in addition to mechanical options and synthetic pesticides. However, there is limited information available on the efficacy and toxicology of plant essential oils against bed bugs. This project was designed with the aim to provide in-depth information on efficacy, toxicology and mode-of-action of essential oils and their insecticidal constituents in bed bugs. Initially, I evaluated topical and fumigant toxicity of fifteen essential oil components against adult male bed bugs of the Harlan strain (an insecticide susceptible strain). Neurological effects of the six most toxicologically active compounds were also determined. In both topical and fumigant bioassays, carvacrol and thymol were the most active compounds. Spontaneous electrical activity measurements of the bed bug nervous system demonstrated neuroinhibitory effects of carvacrol, thymol and eugenol, whereas linalool and bifenthrin (a pyrethroid class insecticide) produced excitatory effects. Further, I evaluated the efficacy and neurological impacts of a mixture of three neuroinhibitory compounds; carvacrol, eugenol and thymol in 1:1:1 ratio against adult male bed bugs of the Harlan strain. This mixture of monoterpenoids as well as the mixture of synthetic insecticides exhibited a synergistic affect in topical bioassays. In electrophysiology experiments, the monoterpenoid mixture led to higher neuroinhibitory effects, whereas a mixture of synthetic insecticides caused higher neuroexcitatory effects in comparison to single compounds.

In the next objective of my dissertation, I compared the efficacy of five plant essential oils (thyme, oregano, clove, geranium and coriander), their major components (thymol, carvacrol, eugenol, geraniol and linalool) and EcoRaider® (commercial product) between pyrethroid susceptible (Harlan) and field collected (Knoxville) bed bug populations. Initially, I found that the Knoxville strain was 72,893 and 291,626 fold resistant to topically applied deltamethrin (a pyrethroid class insecticide) compared to the susceptible Harlan strain at the LD25 and LD50 lethal dose levels, respectively. Synergist bioassays and detoxification enzyme assays showed that the Knoxville strain possesses significantly higher activity of cytochrome P450 and esterase enzymes. Further, Sanger sequencing revealed the presence of the L925I mutation in the voltage gated sodium channel gene. The Knoxville strain, however, did not show any resistance to plant essential oils, their major components or EcoRaider® in topical bioassays (resistance ratios of ~ 1). In the final objective, I evaluated the efficacy of binary mixtures of above-mentioned essential oils or their major components or EcoRaider® with deltamethrin in susceptible and resistant bed bugs. In topical application bioassays, binary mixtures of essential oils or their major components or EcoRaider® and deltamethrin at the LD25 dose caused a synergistic increase in toxicity in resistant bed bugs. Further, I studied the inhibitory effects of major essential oil components on detoxification enzyme activities (cytochrome P450s, esterases and glutathione transferases). Detoxification enzyme assays conducted using protein extracts from bed bugs pre-treated with essential oil constituents showed that these compounds significantly inhibited cytochrome P450 activity in the resistant strain, but esterase and glutathione transferase activity were unaffected. No inhibition of detoxification enzyme activities was observed in the Harlan strain bed bugs pre-treated with essential oil constituents.

In conclusion, my dissertation research has created the foundation for utilization of natural products for bed bug management by (i) describing the efficacy of plant essential oils and their components against bed bugs, (ii) discovering synergistic interactions between essential oil components at the nervous system level, (iii) determining susceptibility of deltamethrin-resistant bed bugs to plant essential oils and their constituents and (iv) identifying synergistic effects of essential oils or their components on toxicity of pyrethroid insecticides and underlying mechanisms of this synergistic interaction.


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45

Hsu, Chih-Chieh, e 許智捷. "Effects of Essential Oils on Candida albicans Biofilms". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/41347518823595630707.

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Abstract (sommario):
博士
國立陽明大學
生化暨分子生物研究所
101
Biofilms are structured microbial communities in which the cells bind tightly to a surface and become embedded in a matrix of extracellular polymeric substances produced by these cells, and characteristically display a phenotype that is markedly different from that of planktonic cells. Candida albicans, the dimorphic yeast, is a major human fungal pathogen that causes both mucosal and deep tissue infections. Biofilm-associated Candida albicans infections are clinically relevant due to their high levels of resistance to traditional antifungal agents. Essential oils are aromatic oily liquids obtained from plant materials that are mainly composed of terpenes and some other non-terpene components. The essential oils of many aromatic plants are known for their antifungal properties, but their antibiofilm activity has not been studied extensively. The aim of this study is to investigate whether essential oils and its components could inhibit the development of C. albicans biofilms. In our screen system, biofilms were formed on microtiter plates and quantified by XTT reduction assay. After preliminary screening, several candidate essential oils and their major components were found to inhibit C. albicans biofilm formation and linalool was chosen for further study. Linalool exhibited antifungal activity against C. albicans ATCC 14053, with a minimum inhibitory concentration of 8 mM. Sub-MIC concentrations of linalool also inhibited the formation of germ tubes and biofilms in that strain. The defective architecture of C. albicans biofilms exposed to linalool was characterized by scanning electron microscopy. The expression levels of the adhesin genes HWP1 and ALS3 were downregulated by linalool, as assessed by real-time RT-PCR. The expression levels of CYR1 and CPH1, which encode components of the cAMP-PKA and MAPK hyphal formation regulatory pathways respectively, were also suppressed by linalool, as was the gene encoding their upstream regulator Ras1. The expression levels of long-term hyphae maintenance associated genes, including UME6, HGC1, and EED1, were all suppressed by linalool. These results indicate that linalool may have therapeutic potential in the treatment of candidiasis associated with medical devices because this compound interferes with the morphological switch and biofilm formation of C. albicans.
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46

De, Rapper Stephanie. "Synergistic interactions of lavender essential oil". Thesis, 2014.

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Thesis (M.Pharm.)--University of the Witwatersrand, Faculty of Health Sciences, 2013.
Essential oils are not only used singularly but have been used in combination for many years. There is, however, very little scientific evidence to support the claims made for combined antimicrobial efficacy. With this in mind, a study was designed to investigate the antimicrobial activity of Lavender (Lavandula angustifolia) essential oil, in combination with other essential oils with antimicrobial relevance. The micro-dilution minimum inhibitory concentration (MIC) assay was undertaken, whereby the fractional inhibitory concentration (ƩFIC) was calculated for 54 oil combinations. When lavender oil was assayed in 1:1 ratios with other oils, synergistic (23.5%), additive (52.5%), non-interactive (23.5%) and antagonistic (0.5%) interactions were observed. Four 1:1 combinations were synergistic against Candida albicans and Staphylococcus aureus (Lavandula angustifolia in combination with Daucus carota (ΣFIC 0.50 and 0.50); Juniperus virginiana (ΣFIC 0.50 and 0.50); Cinnamomum zeylanicum (ΣFIC 0.40 and 0.50) and Citrus sinensis (ΣFIC 0.42 and 0.38)). In order to understand the antimicrobial potential of these synergistic essential oil combinations, further antimicrobial analysis was undertaken whereby the oils were placed in varying ratios. Two of the four combinations (Lavandula angustifolia in combination with either Cinnamomum zeylanicum or Citrus sinensis), were identified as the most promising, demonstrating synergy at varying ratios, and thus the major chemical constituents of the essential oils were investigated further. The major chemical constituents identified in Lavandula angustifolia (GC-MS) were linalyl acetate (36.7%), linalool (31.4%) and terpinen-4-ol (14.9%). The GC-MS profiles for all other oils in the study were also confirmed. The major chemical constituents of the most promising essential oil combinations were investigated in equal and varying ratios to determine the effect of chemistry on antimicrobial outcome. When one of the major essential oil constituents (linalyl acetate) of Lavandula angustifolia was combined with limonene found in Citrus sinensis, synergistic interactions were noted for all nine combinations against C. albicans; including the ratio at which the two major constituents would be mixed should the two oils be combined. Lavandula angustifolia essential oil was placed in combination with four conventional antimicrobial agents (ciprofloxacin, chloramphenicol, fusidic acid and nystatin) to determine which of these agents in combination with Lavandula angustifolia would demonstrate the best antimicrobial effect. Synergy was determined for Lavandula angustifolia in combination with ciprofloxacin against S. aureus (ΣFIC of 0.49) and Lavandula angustifolia in combination with chloramphenicol against P. aeruginosa (ΣFIC of 0.29). No antagonism was noted for the combinations investigated. When placed in variable ratios it was identified that Lavandula angustifolia provided the pivotal role in the synergistic interactions observed against C. albicans and S. aureus, with ratios higher in Lavandula angustifolia essential oil concentration showing considerably better antimicrobial effects. In order to determine the antimicrobial effects of Lavandula angustifolia in triple essential oil combinations, the method of MODDE® Design of Experiments was employed. The Design of Experiments (MODDE 9.1®) software identified that Lavandula angustifolia (from the combination of Lavandula angustifolia: Citrus sinensis: Cedrus atlantica) and Thymus vulgaris (from the combination of Lavandula angustifolia: Daucus carota: Thymus vulgaris) were the essential oils with the greater antimicrobial effect in the combinations analysed. Lavender remains one of the most sought after essential oils. This comprehensive study on the antimicrobial effects of Lavender (Lavandula angustifolia) combinations demonstrates promising in vitro effects and lends some credibility for combined use in aromatherapy for the treatment of infections
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47

Montgomery, K. "The effects of Roman chamomile, spike lavender, petitgrain, and rosemary essential oils on psychological, physiological, and psychophysiological processes". Thesis, 2005. https://eprints.utas.edu.au/20941/1/whole_MontgomeryKate2005_thesis.pdf.

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Abstract (sommario):
The overriding aim of this series of studies was to investigate the psychological, physiological, and psychophysiological effects of exposure to odours of purportedly sedative (petitgrain and Roman chamomile) and stimulant (rosemary and spike lavender) essential oils. More specifically, the purpose of these studies was to determine whether inhalation of essential oils produces reliable changes in mood, behavioural responding, physiological functioning, psychological functioning, and cognitive processing, as well as whether these changes are consistent with the supposed therapeutic effects of these oils as cited in aromatherapy literature. Furthermore, these studies aimed to extend the current knowledge regarding the mechanisms via which the inhalation of essential oils may produce changes in human functioning. In particular, the aim of the studies was to investigate the direct versus indirect action of essential oils on nervous system functioning by removing, controlling, or specifically assessing the effects of variables that are hypothesised to mediate an individual's response to an odour. These mediating variables include hedonic ratings of odour pleasantness, expectations regarding the purported therapeutic effects of the odours, and semantic associations arising from previous experiences with the odours. Consequently, all participants (n=17, females) were screened for knowledge of the experimental odours and were required to rate each odour according to its pleasantness and to identify whether exposure to each odour elicited particular memories. Study One measured changes in self-report ratings of 10 mood dimensions following odour exposure. Study Two assessed the effects of exposure to the odours of the experimental oils on accuracy and reaction time on a visual three-stimulus odd-ball task. In Study Three, changes in physiological parameters such as heart rate, respiration rate and respiratory sinus arrhythmia were assessed in response to odour exposure. Study Four investigated the effects of odour exposure on electroencephalographic responses in the alpha, beta, and theta frequencies. Finally, Study Five assessed the effects of exposure to the experimental odours on the Ni, N2, P2, P3a and P3b components of event-related potentials. In each of these studies, the overall effects of odour exposure on each of the experimental parameters was assessed, as well as the contributing effects of ratings of odour pleasantness and the presence or absence of semantic associations. Overall, the results revealed that there is a complex relationship between experimental parameters, odour type, hedonic ratings, and semantic associations. There are inconsistent results across studies for each of the experimental odours, and the effects of ratings of odour pleasantness or the existence of semantic associations on each experimental parameter varied between essential oil odour types. The fact that the variability in the results was not fully accounted for by the effects of the hedonic and semantic variables alone suggests that there may be other factors that contribute to the action of essential oils on humans.
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48

Saraiva, Carla Sofia da Silva. "Bioherbicidal effect of plant aqueous extracts and essential oils". Master's thesis, 2019. http://hdl.handle.net/10400.26/28202.

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Abstract (sommario):
Resumo A População Mundial está a aumentar, prevendo-se 10 biliões de pessoas na terra em 2050. Para obter o maior rendimento de culturas, é crucial controlar as infestantes, pois causam uma perda da produção total anual de aproximadamente 9,7%. Durante muitos anos os herbicidas controlaram eficazmente as infestantes e sem estes a Revolução Verde não aconteceria, mas o seu uso abusivo a nível mundial, levou à emergência de infestantes resistentes a herbicidas e a elevados níveis de resíduos no solo, água e alimentos. Os Bioherbicidas podem ser uma alternativa natural aos herbicidas sintéticos, evitando impactos negativos no meio ambiente e na saúde humana, pois os ingredientes ativos são compostos naturais já presentes no ambiente, espectando-se serem mais ecológicos. Este trabalho teve como objetivo estudar a atividade herbicida pré e pós-emergente de seis extratos aquosos e oito óleos essenciais de plantas PAM, no dente-de-leão, Taraxacum officinale. Extratos Aquosos mostraram maior inibição da germinação no ensaio pré-germinativo, enquanto os Óleos essenciais maiores níveis de lesão no ensaio pós-emergente. Para avaliar o potencial e os mecanismos de ação destes extratos vegetais e óleos essenciais como bioherbicidas, e garantir o não comprometimento da biodiversidade e do desenvolvimento das culturas, mais estudos deverão ser realizados.
Abstract World Population is increasing and 10 billion people are expected by the year 2050. To obtain the largest crop yields, it is crucial to control weeds, as they cause about 9.7% loss of total crop production every year. Herbicides have effectively controlled weeds for many years. Nonetheless, their worldwide overuse led to herbicide-resistant weed and high levels of herbicide residues in soil, water and food. Therefore, bioherbicides can be a natural alternative to synthetic herbicides, avoiding such negative impacts on environment and human health. Since bioherbicides have natural compounds as active ingredients already present in the environment, they are expected to be more ecologically friendly. Thus, this work aimed to study the pre and post emergent herbicidal activity of six Aromatic and Medicinal Plants (AMP), plant aqueous extracts and eight AMP essential oils, on dandelion, Taraxacum officinale. Aqueous extracts showed better seed germination inhibition on pre-emergency bioassay while essential oils had a higher injury level on post-emergency bioassay. More detailed studies should be carried out to better evaluate the potential and mechanisms of action of these plant extracts and essential oils as bioherbicide, in order to ensure that possible side effects will not neither compromise biodiversity nor crop development.
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49

Leite, Bianca. "Extraction of essential oils from vetiver (vetiveria zizanioides) grass". Thesis, 2012. http://hdl.handle.net/10413/9215.

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Vetiver grass is a viable vegetative absorbent and erosion barrier; in addition the valuable oils extracted from its roots are playing an increasing role in the perfume, food and pharmaceutical industries. The quantity and quality of oil extracted from the vetiver grass depends strongly on location of growth, and the extraction and separation techniques adopted. The aim of this research project is to evaluate whether the harvesting and extracting of essential oils from locally grown vetiver grass would be a feasible business idea, as well as, which extraction technique will give the highest yield of vetiver oil. The extraction methods tested are solvent extraction, hydro distillation and supercritical carbon dioxide extraction. Due to the lack of supercritical fluid extraction equipment available a large portion of the research project was on the design and setup of a supercritical fluid extraction unit. The experimental investigations undertaken using solvent extraction in a soxhlet apparatus with hexane as the extracting agent gave an average yield of +-1.6% for a 5 hour run which is slightly lower than the yield of 1.91% for a 5 hour run stated in literature. According to the experimental results, yields of up to approximately 2% for hexane extraction can be achieved by increasing the extraction time to 12 hours. The vetiver roots were also hydro-distilled in a clevenger apparatus for 16 hours (extraction time); this produced a yield of approximately 0.18 to 0.35%. According to literature hydrodistillation of vetiver roots in a similar apparatus resulted in an average yield of 1.8% for a 16 hour run. This showed that the heavier components of the vetiver oil were not released during the hydro-distillation extraction. Research shows that supercritical carbon dioxide extraction (SCE) produces the highest yields ranging from 2.9 to 3.74% when using the recommended parameters of 190 bar and 50°C. Experimentally a yield of approximately 2.3% was achieved by SCE at 180 bar and 40°C. This yield is lower than that seen in literature due to the lower operating temperature and pressure; however SCE gives a higher yield than the other methods tested in this investigation. The composition of the vetiver oil extracts were analysed using gas-chromatography techniques and this showed that a large percentage of nootkatone is present when using the hydro distillation technique, whilst a large percentage of zizanoic acid was present when using the solvent extraction technique. However a minimal percentage zizanoic acid with higher percentages of nootkatone and khusimol are present in the SCE extracts. The solvent extraction technique gives high yield with high percentage invaluable zizanoic acid whereas hydro-distillation gives very low yields but no zizanoic acid with high percentages valuable nootkatone and khusimol. SCE gives slightly higher yields of vetiver oil than solvent extraction and it contains very minimal zizanoic acid with higher percentages of nootkatone and khusimol. It was therefore concluded that SCE would be the best extraction method for these particular vetiver roots. For a pilot scale SCE extractor the total annual sales was estimated as R 453 420 and the total operating costs per annum were estimated to be R 4 839 813. Therefore from this preliminary feasibility study it is seen that the total operating costs far exceed the total annual sales and hence the business is not profitable.
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012.
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50

CHEN, YEN-JEN, e 陳妍蓁. "Assessments of preservative efficiency of cosmetics with essential oils". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/2g3mn5.

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Abstract (sommario):
碩士
嘉南藥理科技大學
化妝品科技研究所
99
Microorganism contamination is one of the most important problems in cosmetic industry, and microorganism lead to product degradation or, in the case of pathogens, constitute a risk for the health of the consumer. Therefore, preservatives inhibiting the growth of microorganisms are added to a product, but allergies after using cosmetics occur more and more frequently, which is quite often associated with the presence of synthetic preservatives. For this reason, this study was to verify the antimicrobial activity of essential oils as the components of preservative. The aim of the study was to test preservative effectiveness of Rosmarinus officinalis L. and Cymbopogon citratus essential oils alone or combination in the formulation during the challenge test. The compositions of the two essential oils, were analyzed by GC/MS. The main components of Rosmarinus officinalis L. essential oil is 1,8-cineole (24.70%). Cymbopogon citratus essential oils contains geranial (17.68%) and cis-citral (15.06%). In the challenge test, all formulation had preservative abilities against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. However, all formulations had preservative abilities against Aspergillus niger administered alone or in combination of Cymbopogon citratus essential oil. In summary, the essential oils can be added individually or in com- bination into cosmetics to achieve the preservative effect.
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