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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Therapeutic Potential of Essential Oil-based Microemulsions: Reviewing State-of-the-art

Thakur, Divya, Kaur, Gurpreet, Puri, Ashana, Nanda, Rajat 01 January 2021 (has links)
A pre-eminent emulsion-based micellar drug delivery system, "microemulsion", comprising drug in oil or water phase, stabilized by surfactants and co-surfactants, has been evidenced to have a phenomenal role in a number of applications. Oils play an important role in the formation of ME and increase the drug absorption at the site of action. Oils employed in microemulsion formulation solubilize lipophilic drug. As the concept of "natural" therapies is recently gaining importance amongst researchers all over the world, scientists are employing essential oil as an organic component in this system. The active components of essential oils include flavonoids, phenylpropanoids, monoterpenes and polyunsaturated mega-6-fatty acids. These oils are enriched with characteristic intrinsic properties such as anti-oxidant, anti-bacterial, anti-viral, etc., bestowing enhanced supremacy to the whole microemulsion system. This mini-review is the first to document various types of essential oils employed in microemulsion systems and highlight their therapeutic potential and applications as drug delivery vehicles. Key inferences from this study suggest: 1) Clove oil is the most explored oil for incorporation into a microemulsion based system, followed by peppermint and Tea Tree Oil (TTO). 2) Penetration enhancing effects of these oils are due to the presence of terpenic constituents. 3) Essential oil based microemulsions protect volatility of ethereal oils and protect them from degradation in the presence of light, air, temperature. 4) These systems may also be explored for their applications in different industries like aromatherapy, food, drink, fragrance, flavour, cosmeceutical, soap, petroleum and pharmaceutical industry.
12

EFEITO DA TEMPERATURA DA ÁGUA E DA SEDAÇÃO COM EUGENOL NA SOBREVIDA DO PLATI (Xiphophorus maculatus Günther)

Pacheco, Janeth Teresinha Coelho 30 September 2009 (has links)
Made available in DSpace on 2016-08-10T10:31:06Z (GMT). No. of bitstreams: 1 JANETH TERESINHA COELHO PACHECO.pdf: 1703369 bytes, checksum: fd4af18f947da434675e2f30a0d96019 (MD5) Previous issue date: 2009-09-30 / This study evaluated the sedative action of six eugenol concentrations (0, 3, 5, 7, 9 and 12 mg/L water) and five water temperatures (22, 24, 26, 28 and 30°C) on the time for the beginning of death in plati (Xiphophorus maculatus) juveniles, to allow high densities, optimizing the costs with transport costs by reducing the total weight of the loads. Six hundred fish, measuring 0.61±0.3g and 3.2±0.53 cm, in four repetitions of 5 fish per experimental unit (plastic bag) per temperature and concentration, in a total of 30 treatments were used. The results indicated that the time delay until death of the first fish in each experimental unit and the dissolved oxygen concentration were significantly affected by temperature (T), eugenol concentration (E) and the interaction of these factors (TxE). This study suggests that the time delay until death of the first fish and the dissolved oxygen concentration were interactively affected by water temperature and eugenol concentration. Eugenol, when diluted in water concentrations around 8 mg L-1 at 22ºC and 9 mg L-1 at 24ºC, allows greater survival time for the fish, but has no effect at higher temperatures. / Este trabalho avaliou a ação sedativa de seis diferentes concentrações de eugenol (0, 3, 5, 7, 9 e 12 mg/L de água) e cinco temperaturas de água ( 22, 24, 26, 28 e 30°C) no tempo para o início da mortalidade em juvenis de plati ( Xiphophorus maculatus), visando permitir altas densidades, otimizando os custos com os serviços de transporte pela redução no peso total das cargas. Foram utilizados 600 peixes com 0,61± 0,3g e 3,2 ±0,53 cm, em 04 repetições de 5 peixes por parcela (saco plástico) por temperatura e concentração, totalizando 30 tratamentos. Os resultados obtidos mostraram que o tempo decorrido até a morte do primeiro peixe de cada parcela e a concentração de oxigênio dissolvido na água tiveram influência altamente significativa da temperatura(T), da concentração do eugenol (E) e da interação entre esses (TxE). Este trabalho sugere que o tempo decorrido até a morte do primeiro peixe e a concentração de oxigênio dissolvido na água sejam influenciados de modo interativo, pela temperatura da água e a concentração de eugenol. O eugenol propicia maior tempo de sobrevivência dos peixes quando diluído na água nas concentrações em torno de 8 mg.L-1 a 22ºC e 9 mg.L-1 a 24ºC, mas não tem efeito em temperaturas maiores.
13

AVALIAÇÃO DE COMPOSTOS PUROS E MISTO DE ÓLEO DE CRAVO E MELALEUCA, NA SEDAÇÃO DE TILÁPIA DO NILO (Oreochromis niloticus).

Freitas, Rafael Alves de 24 February 2015 (has links)
Made available in DSpace on 2016-08-10T10:44:49Z (GMT). No. of bitstreams: 1 RAFAEL ALVES DE FREITAS.pdf: 1312091 bytes, checksum: 9a5914dcc41d33316a41e660ea64dacf (MD5) Previous issue date: 2015-02-24 / The present study aimed to evaluate the changes in hematological parameters of Nile tilápia (Oreochromis niloticus ) according sedation due to different tea tree oil and clove combinations. 230 fish were used with 66 g ± 18.56 g, clove oil submitted to solutions containing 0%, 20%, 40%, 60 %, 80% and 100% tea tree oil. at a concentration of 100 mg - L, a total of 6 treatments and the control group. So, we used 20 transparent plastic buckets 1.5 liter , 6 and 10 liter aquariums. Where the fish were individualized for observation of sedation and recovery times, at the time the fish reached stage 5 sedation, were selected for blood collection, that repeated 1 hour and 24 hours after sedation, with 10 fish every collect. The analysis of pH , dissolved oxygen, ammonia water and fish biometrics occurred before sedation, and at the time of each blood collect. The results showed that the clove oil , and tea tree oil solutions influence on hematological parameters, in the time sedation and fish behavior. It can be concluded that the tea tree oil is suitable for sedation Nile tilápia. At the same time it is concluded that the tea tree oil can be used in conjunction with clove oil with the objective of mitigating the negative effects caused by pure clove oil / O objetivo deste trabalho foi verificar as alterações dos parâmetros hematológicos de tilápia do Nilo (Oreochromis niloticus ) em função da sedação com diferentes combinações de óleo de cravo e melaleuca. Foram utilizados 230 peixes com 66 g ± 18,56 g, submetidos a soluções de óleo de cravo com 0%, 20%, 40%, 60%, 80% e 100% de óleo de melaleuca, a uma concentração de 100 mg-L, totalizando 6 tratamentos e o grupo controle. Assim, foram utilizados 20 baldes plásticos transparentes de 1,5 litros, e 6 aquários de 10 litros, onde os peixes foram individualizados para observação dos tempos de sedação e recuperação. No momento em que os peixes alcançaram o estágio 5 de sedação, foram selecionados para coleta de sangue, que se repetiu 1 hora e 24 horas após a sedação, com 10 peixes a cada coleta. A análise do pH, oxigênio dissolvido, amônia da água e biometria dos peixes ocorreu antes da sedação, e no momento de cada coleta de sangue. Os resultados mostraram que as soluções de óleo de cravo e óleo de melaleuca influenciaram nos parâmetros hematológicos, no tempo de sedação e no comportamento dos peixes. Pode-se concluir que o óleo de melaleuca é apropriado para sedação de tilápia do Nilo. Paralelamente conclui-se que o óleo de melaleuca pode ser usado em associação com óleo de cravo com o objetivo de amenizar os efeitos negativos causados pelo óleo de cravo puro.
14

Elabora??o e caracteriza??o de filmes de amido e polpa de acerola por casting, extrus?o termopl?stica e termoprensagem / Elaboration and characterization of starch films with acerola pulp for casting, thermoplastic extrusion and thermopressing

FARIAS, M?nica Guimar?es 06 April 2016 (has links)
CAPES / Due to the environmental impact generated by the continued use of inert material derived exclusively from petroleum, there was an increase in research aimed at developing of films for packaging based on biopolymers, because they are degraded in composting conditions, not harm the environment. Films produced by biopolymer based perform support nutrients functions, preservation of bioactive, improved nutritional and sensory food characteristics of bringing with their quality and shelf life. In this context, the polysaccharides as an alternative because they are able to form solid polymeric matrices. The objective of this study was to develop and characterize flexible biodegradable films from natural polymers from renewable sources (starch), incorporated acerola pulp and clove essential oil (OEC) as antioxidant additives, antimicrobials, sources of vitamin C and carotenoids, prepared by casting process, aiming the choice of the best formulation for production of bioplastics by extrusion and pressing process. The filmogenic solutions were prepared at fixed concentrations of cassava starch (4%), acerola pulp (34.54%) and varying concentrations of glycerol (30; 22,5; 15; 7,5 and 0%) and OEC (0; 7,5, 15, 22,5 and 30%). One step of this study was to evaluate the bacteriostatic ability of the OEC and composite films with him against the bacteria Staphylococcus aureus of Gram-positive group and Salmonella tiphymurium of the Gram-negative group, and the fungus Penicillium sp. and Aspergillus flavus. All formed films were visually transparent and homogeneous. The substitution of glycerol for OEC caused no statistically significant difference in the properties of thickness, water activity (AW) and to water vapor permeability (WVP). The reduced glycerol content, proportional to the increase in concentration of OEC, increased total solids, vitamin C, carotenoids, ?-carotene and antioxidant activity by DPPH and ABTS and the reduction of the moisture content. The reduction of the glycerol content until 15% favored increased stress and strain at tensile and puncture and young modulus, after this limit has shown a drastic reduction in these properties. The desirability function used in the optimization process for selecting the best film produced by casting, to reproduce by extrusion and pressing. The extruded and compressed bioplastic obtained under the same conditions (starch concentration, pulp, glycerol and OEC) that formed by casting, was flexible, visually homogeneous and showed lower values for total solids, tensile deformation, puncture force, vitamin C, carotenoids and ?-carotene contents, and higher values in moisture and antioxidant activity by DPPH. Losses of bioactive were analyzed between each step of the casting process and extrusion, separately. Therefore, the incorporation of pulp acerola and clove essential oil in cassava starch biofilms gave a pronounced protective effect of the bioactive, altering the physical, chemical and mechanical properties. / O impacto ambiental gerado pelo uso cont?nuo de material inerte, oriundo exclusivamente de derivados de petr?leo, tem favorecido o aumento nas pesquisas visando o desenvolvimento de filmes para embalagem a base de biopol?meros, pois estes em condi??es de compostagem s?o reincorporados ao ambiente. Al?m disso, os filmes a base de biopol?meros podem desempenhar fun??es de suporte de nutrientes, preserva??o de bioativos, melhoria das caracter?sticas nutricionais e sensoriais dos alimentos, elevando sua qualidade e vida ?til. Neste contexto, os polissacar?deos apresentam-se como alternativa, pois s?o capazes de formar matrizes polim?ricas cont?nuas. O objetivo deste trabalho foi desenvolver e caracterizar filmes flex?veis biodegrad?veis ativos a partir de amido, incorporados de polpa de acerola e ?leo essencial de cravo (OEC) como aditivos antioxidantes, antimicrobianos, fontes de vitamina C e carotenoides, elaborados pelos processos de casting, extrus?o e termoprensagem. Nos filmes por casting, as solu??es filmog?nicas foram elaboradas em concentra??es fixas de amido de mandioca (4%), polpa de acerola (34,54%) e concentra??es variadas de glicerol (30; 22,5; 15; 7.5 e 0%) e OEC (0; 7,5; 15; 22,5 e 30%) em rela??o ao peso do amido. Sendo, os aditivos glicerol e OEC representados por 30% na base de amido. Uma etapa deste estudo consistiu em avaliar a capacidade antimicrobiana do OEC e dos filmes compostos adicionados deste. Esta avalia??o foi realizada por meio do teste de difus?o em ?gar com as bact?rias Staphylococcus aureus do grupo Gram-positivo e Salmonella tiphymurium do grupo Gram-negativo e dos fungos Penicillium sp. e Aspergillus flavus. Os filmes formados foram visualmente transparentes e homog?neos. A substitui??o do glicerol por OEC n?o provocou diferen?a estatisticamente significativa nas propriedades de espessura, atividade de ?gua (Aw) e permeabilidade ao vapor de ?gua (PVA). A redu??o do teor de glicerol, proporcional ? eleva??o da concentra??o de OEC, aumentou o teor de s?lidos totais, vitamina C, carotenoides totais, ?-caroteno, atividade antioxidante e a redu??o do teor de umidade. A redu??o do teor de glicerol at? 15% favoreceu o aumento da tens?o e deforma??o nos ensaios de tra??o e de perfura??o, bem como do m?dulo de elasticidade, ap?s este limite, foi evidenciada uma redu??o dr?stica nestas propriedades. A fun??o desejabilidade foi utilizada no processo de otimiza??o para sele??o do filme ideal (elevado teor de vitamina C, carotenoide e ?-caroteno, maior resist?ncia e deforma??o nos ensaios de tra??o e perfura??o, elevada capacidade antioxidante e m?dio m?dulo de elasticidade) elaborado por casting, para reprodu??o por extrus?o e prensagem. O biopl?stico extrusado e prensado obtido nas mesmas condi??es (concentra??o de amido, polpa, glicerol e OEC), que o formado por casting, foi flex?vel, visualmente homog?neo e apresentou menores valores para deforma??o na tra??o, for?a na perfura??o, teor de vitamina C, carotenoides, ?-caroteno e capacidade antioxidante por DPPH. Foram analisadas as perdas de bioativos entre cada etapa dos processos casting e extrus?o, separadamente. Possivelmente, a incorpora??o de ?leo essencial de cravo conferiu um pronunciado efeito protetor dos bioativos da polpa de acerola nos biofilmes de amido de mandioca, alterando as propriedades f?sico-qu?micas e mec?nicas.
15

Investigação da Atividade Antifúngica do Óleo Essencial de Eugenia caryophyllata Thunb. sobre cepas de Candida tropicalis / Investigation of Antifungal Activity of Essential oil Eugenia caryophyllata Thunb. on strains of Candida tropicalis.

Mendes, Juliana Moura 13 December 2011 (has links)
Made available in DSpace on 2015-05-14T12:59:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1755870 bytes, checksum: 96ad104e1f5d7b4eee083c5643e9708f (MD5) Previous issue date: 2011-12-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The candidiasis is a fungal opportunistic infections involving Candida. In Brazil, the specie C. tropicalis is the second most commonly isolated after C. albicans. The emergence of strains resistant to conventional antifungal agents has increased the search for new alternatives from natural products, especially essential oils. This study investigated the activity of essential oil (EO) Eugenia caryophyllata Thunb.(clove) on strains of C. tropicalis by Minimum Inhibitory Concentration (MIC), Minimum Fungicidal Concentration (MFC), Micromorphology, fungal viability (time-kill) and checkerboard. The CIM and CFM were respectively 512 and 1024 μg/mL for the essential oil and 2 μg/mL for amphotericin B. When we evaluated the action of OE and amphotericin B on the morphology of the clinical strain, we observed inhibition of the formation of hyphae and pseudohyphae, which are important virulence factors in the development of candidiasis. There was also the essential oil has a concentration-dependent antifungal activity and that the association of OE and amphotericin B demonstrated effect additive. Given this, it is concluded that the essential oil of E. caryophyllata showed a strong inhibitory activity against C.tropicalis and thus can be considered as a potential product with antifungal properties, especially for the treatment of candidiasis. / As candidíases são infecções fúngicas de caráter oportunista, envolvendo leveduras do gênero Candida. No Brasil, a espécie C. tropicalis é a segunda mais comumente isolada após C. albicans. O surgimento de cepas resistentes aos antifúngicos convencionais tem aumentado a busca por novas alternativas provenientes de produtos naturais, em especial os óleos essenciais. Este trabalho investigou a atividade do óleo essencial (OE) de Eugenia caryophyllata Thunb. (cravo-da-índia) sobre cepas de C. tropicalis, através da Determinação da Concentração Inibitória Mínima (CIM), da Concentração Fungicida Mínima (CFM), do efeito sobre micromorfologia, da viabilidade fúngica (time-kill) e ensaio de sinergismo (checkerboard). A CIM e CFM foram 512 e 1024 μg/mL, respectivamente, para o óleo essencial e 2 μg/mL para anfotericina B. Quando foi avaliada a ação do OE e da anfotericina B sobre a micromorfologia da cepa clínica, observou-se inibição da formação das hifas e pseudohifas, que são fatores de virulência importantes no desenvolvimento das candidíases. Observou-se também o óleo essencial tem atividade antifúngica dependente da concentração e do tempo, e que a associação do OE e anfotericina B demonstrou efeito aditivo.Dessa forma, pode-se concluir que o óleo essencial de E. caryophyllata apresenta forte atividade antifúngica, podendo ser objeto para estudos mais aprofundados acerca dessa atividade.
16

Efeitos subletais de óleos essenciais associados com Bacillus thuringiensis var. aizawai sobre Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). / Subsonic effects of essential oils associated with Bacillus thuringiensis var. Aizawai on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae).

CRUZ, Glaucilane dos Santos 01 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T15:23:56Z No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1016632 bytes, checksum: cf89201a0bacd4f7695775c34d5d1ad4 (MD5) / Made available in DSpace on 2016-11-24T15:23:56Z (GMT). No. of bitstreams: 1 Glaucilane dos Santos Cruz.pdf: 1016632 bytes, checksum: cf89201a0bacd4f7695775c34d5d1ad4 (MD5) Previous issue date: 2012-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A large investment is annually demanded to control the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), which is the major insect pest of corn. To contain this demand alternative methods have been developed, including the use of botanical insecticides, known as essential oils, and entomopathogenic agents such as the bacterium Bacillus thuringiensis Berliner. These alternatives are adequate to Integrated Pest Management purposes, by being selective, low toxic to mammals and present efficiency against various pest species. Thus, we tested the hypothesis that association of long pepper and cloves oils at the concentrations of 30 and 50 mg/L DMSO with Xentari® WG (B. thuringiensis subsp. aizawai - Bta) (1000 mg/L) produces an efficient control of S. frugiperda, affecting biological, immunological and reproductive parameters, and if those concentrations of these oils affect spermatogenesis, the histochemistry of the ovarioles, as well as its impact on fertility. The results demonstrated that long pepper essential oil at a concentration of 50 mg/L associated with Bta has promoted lower larval survival, and clove does not proved efficient when combined with the Bta formulated. However, both oils, associated or not to Bta, interfered on the biology and humoral immunity of S. frugiperda. All treatments showed ovicidal effect except clove oil at the two concentrations without Bta. Histological analysis showed that clove and long pepper oils at the concentrations of 30 and 50 mg/L have affected spermatogenesis and the histochemistry of the ovarioles of S. frugiperda, reflecting on their reproduction. However, the effects of long pepper oil associated or not to Bta were more expressive, proving to be a promising tool to control this pest, adapting to MIP, controlling the survival of offspring and its success in the culture. / Anualmente demanda-se um alto investimento no controle da lagarta do cartucho Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), sendo esta a principal praga da cultura do milho. Para conter esta demanda métodos alternativos tem sido desenvolvidos, incluindo a utilização de inseticidas botânicos, conhecidos como óleos essenciais, e agentes entomopatogênicos, como a bactéria Bacillus thuringiensis Berliner. Estas alternativas adéquamse aos propósitos do Manejo Integrado de Pragas, por serem seletivos, de baixa toxicidade a mamíferos e apresentarem eficiência contra várias espécies de pragas. Assim, testou-se a hipótese de que a associação dos óleos de pimenta longa e cravo da Índia nas concentrações 30 e 50 mg/L DMSO com Xentari® WG (B. thuringiensis subsp. aizawai - Bta) (1000 mg/L) produzem um controle eficiente de S. frugiperda, afetando parâmetros biológicos, imunológicos e reprodutivos, e se as concentrações destes óleos afetam a espermatogênese, a histoquímica dos ovaríolos, bem como seu impacto na fertilidade. Os resultados demonstraram que o óleo de pimenta longa na concentração 50 mg/L associado ao Bta ocasionou menor sobrevivência larval, já o cravo da Índia não mostrou-se eficiente quando associado ao Bta formulado. Porém, ambos os óleos associados ou não ao Bta interferiram na biologia e na imunidade humoral de S. frugiperda. Todos os tratamentos afetaram a viabilidade dos ovos exceto a testemunha e o cravo da Índia nas duas concentrações sem Bta. A análise histológica mostrou que os óleos de pimenta longa e cravo da Índia nas concentrações 30 e 50 mg/L afetaram a espermatogênese e histoquímica dos ovaríolos de S. frugiperda, refletindo na sua reprodução. No entanto, os efeitos do óleo de pimenta longa, associado ou não ao Bta, foram mais expressivos, demonstrando ser uma ferramenta promissora no controle desta praga, adequando-se ao MIP, controlando a sobrevivência da prole e seu sucesso na cultura.
17

Efficacité et toxicité de l'eugénol administré à des doses anesthésiantes chez des grenouilles Xenopus laevis.

Goulet, Félix 08 1900 (has links)
L’eugénol permet d’induire une anesthésie chirurgicale chez la grenouille africaine à griffes (Xenopus laevis) sans causer de lésions chez des grosses grenouilles (90-140g). Le premier objectif de la présente étude était de déterminer la durée de l’anesthésie et d’évaluer la dépression du système nerveux central ainsi que les changements de saturation en oxygène et de fréquence cardiaque chez des petites (7.5 ± 2.1 g) et moyennes (29.2 ± 7.4 g) grenouilles Xenopus laevis en fonction du temps d’exposition à un bain d’eugénol de 350 µL/L. Suite à une immersion de 5 ou 10 minutes, la réponse au test à l’acide acétique, au réflexe de retrait et au réflexe de retournement était absente pendant 1 heure (petites grenouilles) et 0,5 heure (moyennes) et l’anesthésie chirurgicale durait au maximum 15 et 30 minutes chez les petites et moyennes grenouilles respectivement. La saturation en oxygène n’était pas affectée de façon significative, mais la fréquence cardiaque était diminuée jusqu’à 1 heure post-immersion dans les deux groupes. Le deuxième objectif était de déterminer la toxicité de l’eugénol chez des grenouilles de taille moyenne après une ou trois administrations à une dose anesthésique, avec ou sans période de récupération d’une semaine. Histologiquement, il y avait de l’apoptose tubulaire rénale et des membranes hyalines pulmonaires après une administration, et de la nécrose hépatique et des hémorragies dans les tissus adipeux après trois administrations. Ces résultats suggèrent que le poids corporel est un paramètre important à considérer lors de l’anesthésie de grenouilles Xenopus laevis par immersion dans l’eugénol. / Eugenol has been shown to induce surgical anesthesia in African clawed frogs (Xenopus laevis) without causing lesions after a single administration in large frogs (90-140g). The first objective of this study was to determine the duration of anesthesia in small (7.5 ± 2.1 g) and medium (29.2 ± 7.4 g) Xenopus laevis frogs and evaluate CNS depression and changes in oxygen saturation and heart rate relative to exposure time in a eugenol bath (350 µL/L). After immersion for 5 or 10 minutes, no responses to the acetic acid test (AAT), withdrawal reflex, and righting reflex were seen for 1 h (small frogs) or 0.5 h (medium frogs), and small and medium frogs were under surgical anesthesia for a maximum of 15 and 30 minutes respectively. Oxygen saturation was not significantly affected by anesthesia, but heart rate was depressed for as long as 1 hour post-exposure in both groups of frogs. The second objective was to determine the toxicity of eugenol in medium frogs after one or three administrations at anesthetic doses, with or without a 1 week recovery period. Histopathology revealed renal tubular apoptosis and pulmonary hyaline membranes after 1 administration, as well as hepatic necrosis and adipose tissue hemorrhages after 3 administrations. These results suggest that body weight is an important parameter to consider when using a eugenol bath for anesthesia of Xenopus laevis frogs.
18

Efficacité et toxicité de l'eugénol administré à des doses anesthésiantes chez des grenouilles Xenopus laevis

Goulet, Félix 08 1900 (has links)
No description available.
19

Préparation à petite et grande échelle des liposomes encapsulant l’huile essentielle de clou de girofle libre et sous forme de complexe d’inclusion dans l’hydroxypropyl-β-cyclodextrine : caractérisation des nanostructures et évaluation de leur effet antioxydant / Preparation at small and lare scale of liposomes encapsulating clove essential oil in free and hydroxypropyl-β-cyclodextrin inclusion complex forms : characterization of nanostructures and evaluation of their antioxidant effect

Sebaaly, Carine 05 January 2016 (has links)
L'huile essentielle de clou de girofle (HECG) et son constituant majeur l'eugénol (Eug) sont reconnus pour leurs propriétés biologiques. Ces principes actifs naturels peuvent constituer des alternatifs aux agents antimicrobiens, antioxydants et anti-inflammatoires de synthèse dans les formulations alimentaires et pharmaceutiques. Cependant, leur utilisation est limitée en raison de leur faible solubilité aqueuse, volatilité et sensibilité à la lumière. Notre travail de thèse porte sur la préparation et la caractérisation des vésicules lipidiques encapsulant l'HECG et l'Eug ainsi que les complexes d'inclusion cyclodextrine/Eug. Dans une première étape, la méthode d'injection éthanolique est utilisée à l'échelle du laboratoire où les paramètres de préparation ont été optimisés. Des phospholipides naturels de soja saturés (Phospholipon 80H et Phospholipon 90H) et insaturés (Lipoid S100) ont été utilisés pour étudier l'effet de l'hydrogénation et de la composition des phospholipides sur les caractéristiques des liposomes. Les conditions optimales ont été par la suite appliquées pour préparer les liposomes à grande échelle par contacteur à membrane et à l'échelle pilote. Des résultats similaires en termes de taille, indice de polydispersité, potentiel zêta, morphologie et taux d'incorporation de phospholipides sont obtenus à petite et grande échelle. Ceci indique la reproductibilité de ces procédés de préparation. Par ailleurs, des complexes d'inclusion d'HP-β-CD/Eug et d'HP-β-CD/HECG sont préparés dans une solution aqueuse et ensuite incorporés dans les liposomes formant un système combiné « drug in cyclodextrin in liposomes, DCL ». Un système en double encapsulation (DCL2) a été également préparé où l'Eug ou l'HECG sont ajoutés dans la phase organique et leurs complexes d'inclusion dans la phase aqueuse. En comparant à une simple incorporation dans les liposomes, DCL et DCL2 améliorent le rendement d'encapsulation de l'Eug et possèdent des tailles plus petites. Les résultats ont montré que les liposomes et les DCLs sont stables et maintiennent l'activité anti-oxydante de l'Eug. De plus, les liposomes protègent l'Eug contre la dégradation induite par les rayons UVC. Les DCLs, dont la particularité est de maintenir une huile essentielle volatile dans un lyophilisat en dépit des pressions très basses appliquées, peuvent être considérés comme un système de vectorisation prometteur de l'HECG et de l'Eug permettant leur utilisation en tant qu'ingrédients dans les préparations cosmétiques, pharmaceutiques, et agroalimentaires / Clove essential oil (CEO) and its major constituent eugenol (Eug) are recognized for their biological properties. These molecules may constitute natural alternatives to synthetic antimicrobial, antioxidant, and anti-inflammatory agents in food and pharmaceutical formulations. However, CEO constituents are volatile, sensitive to light and possess low aqueous solubility, which may limit their wide applications. Our thesis focuses on the preparation and characterization of lipid vesicles encapsulating CEO, Eug and the inclusion complexes cyclodextrin/Eug. In a first step, the ethanol injection method is applied at laboratory scale where the preparation parameters have been optimized. Natural hydrogenated (Phospholipon 80H, Phospholipon 90H) and non-hydrogenated (Lipoid S100) soybean phospholipids were used to study the effect of hydrogenation and phospholipid composition on the characteristics of liposomes. Optimal conditions were then applied to prepare liposomes at large scale by membrane contactor and at pilot scale. Similar results in terms of size, polydispersity index, zeta potential, morphology and phospholipid loading rate were obtained at laboratory and large scale. This indicates the reproducibility of the preparation methods. In addition, HP-β-CD/Eug and HP- β-CD/CEO inclusion complexes were prepared in aqueous solution and were then incorporated into liposomes forming a combined system « drug in cyclodextrin in liposomes, DCL ». Double loaded liposomes (DCL2) were also prepared where CEO or Eug were added in the organic phase and their inclusion complexes in the aqueous phase. Compared to CEO and Eug loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. Results showed that both liposomes and DCLs are stable and maintain the antioxidant activity of Eug. In addition, liposomes protect Eug from degradation induced by UVC irradiation. DCLs, whose characteristic is to keep a volatile essential oil in a lyophilized form despite the very low applied pressures, could be considered as a promising carrier system of CEO and Eug permitting their use as ingredients in cosmetic, pharmaceutical and food industries
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Citlivost adultních ryb různých druhů k anestetiku hřebíčkový olej / Sensitivity to anesthetic clove oil different species of adult fish

ŠKEŘÍK, Jindřich January 2007 (has links)
Nomenclature: Sensitivity to anesthetic clove oil different species of adult fish Sensitivity of breeding fishes of various species (Siberian sturgeon, Brook trout, Black carp- young breeding fishes) for anesthetic clove oil was probed by the tests performed at temperature in the period of stripping (apart from Brook trout and Black carp). The tests were carried out with 17 fish species- with cyprinids (Ide- golden form, Common dace, European Chub, Sneep, Barbel, Grass carp, Black carp, bighead carp), salmonids (Brown trout, Rainbow trout, Brook trout), thymallinae (Grayling), pikes (Northern pike), perches (Pike-perch), sturgeons (Siberian sturgeon, Beluga) and airbreathing catfishes (North African catfish). Using concentration of 0,03ml.l-1 (Brown trout, Rainbow trout, Brook trout, Grayling, Pike, Pike perch, Ide, Dace, Chub, Barbel and Sneep), 0,04ml.l-1 (Grass carp, Black carp, Bighead carp), 0,05ml.l-1 (North African catfish) and 0,07ml.l-1 (Siberian sturgeon, Beluga) the IIb. Phase has been achieved, which is sufficient for manipulation with fishes during stripping. The anesthesia subsided after time period of 10-17 minutes (12 species) at the majority of fishes and at others after interval of 20-26 minutes (5 species). The results confirmed concentrations recommended for salmodis and Grayling (0,025-0,03ml.l-1), sturgeons (0,07ml.l-1), and North African catfish (0,05ml.l-1). At the majority of cyprinids (apart from Grass carp, Black carp and Bighead carp), the concentration used was lower than recommended (0,04-0,05ml.l-1)

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