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Efeitos citoprotetor e citotóxico de Annona glabra (Annonaceae)SARMENTO, Rosana Moura 03 October 2016 (has links)
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Previous issue date: 2016-10-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo avaliou a o potencial citotóxico e citoprotetor de extrato etanólico obtido de cascas de Annona glabra, suas frações e substâncias isoladas. O pó obtido das cascas de A. glabra foi submetido a maceração com etanol por 7 dias, sendo a solução concentrada em rotaevaporador até resíduo. Com o extrato etanólico de A.glabra foi realizado a partição entre hexano:metanol aquoso (9:1). A Fração metanólica foi fracionada em coluna cromatográfica utilizando como fase estacionária Sephadex e fase móvel o metanol. A citotoxicidade do extrato etanólico e frações foi avaliada através do ensaio de viabilidade celular com o MTT (brometo de [3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazólio]). A concentração citotóxica 50% (CI50) foi determinada por regressão linear. O extrato, frações e subfrações foram submetidas a análise em cromatografia em camada delgada (CCD), e reunidas de acordo com características semelhantes. Frações do extrato com CI50 ≤ 30 μg/mL e substância isolada com CI50 ≤ 4 μg/mL são considerados citotóxicos. As frações que apresentaram citotoxicidade moderada a baixa foram submetidas aos ensaios de indução de apoptose e fragmentação de DNA por citometria de fluxo. Também, estas amostras foram submetidas a avaliação de estresse oxidativo pelo método TEAC e DPPH. O extrato de A. glabra (rendimento de 8,39%) foi particionado obtendo-se a fração metanólica (rendimento de 88,14%) e fração hexânica (rendimento de 8,08%). O extrato etanólico, sua fração metanólica e rutina apresentaram baixa citotoxicidade (CI50=137,7; 139,4; > 200 μg/mL, respectivamente). Fração hexânica e subfrações 17 e 19 apresentaram citotoxicidade moderada não significativa (CI50= 45,07; 53,45; 80,65 μg/mL, respectivamente). Todas as amostras avaliadas não induziram células a apoptose, entretanto, extrato etanólico, fração hexânica e rutina promoveram alterações na morfologia das células. Entretanto, fração hexânica, subfrações 6 e 7 apresentaram capacidade de fragmentar DNA das células. O fracionamento do extrato etanólico favoreceu o potencial citotóxico, tendo a fração hexânica como a mais promissora, e a capacidade antioxidantes também foi favorecida tendo o grupo 5 como o mais promissor. Estes resultados sugerem que as amostras de A. glabra apresentam baixo potencial citotóxico, e o mecanismo envolvido não está relacionado a indução de apoptose, e o extrato etanólico contém substâncias com capacidade antioxidante. / The present study evaluated the cytotoxic and cytoprotective potential of ethanolic extract obtained from the shells of Annona glabra, its fractions and isolated substances. The powder obtained from A.glabra husks was subjected to maceration with ethanol for 7 days, and the solution was concentrated in a rotavaporator to residue. The ethanolic extract from A.glabra was partitioned between aqueous hexane: methanol (9: 1). The methanolic fraction was fractionated in chromatographic column using as Sephadex stationary phase and mobile phase the methanol. The cytotoxicity of the ethanolic extract and fractions was evaluated by the MTT cell viability assay ([3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide]). The extract, fractions and subfractions were submitted to thin layer chromatography (CCD) analysis, and pooled according to similar characteristics. The 50% cytotoxic concentration (IC 50) was determined by linear regression. Fractions of the extract with IC50 ≤ 30 μg / mL and isolated substance with IC50 ≤ 4 μg / mL are considered cytotoxic. Fractions with moderate to low cytotoxicity were submitted to the induction of apoptosis and DNA fragmentation by flow cytometry. Also, these samples were submitted to evaluation of oxidative stress by the TEAC and DPPH method. The extract of A. glabra (8.39% yield) was partitioned to give the methanolic fraction (yield 88.14%) and hexane fraction (yield 8.08%). Ethanolic extract, methanolic fraction and rutin showed low cytotoxicity (IC50 = 137.7, 139.4,> 200 μg / mL, respectively). Hexanic fraction and subfractions 17 and 19 showed moderate non-significant cytotoxicity (IC50 = 45.07, 53.45, 80.65 μg / mL, respectively). All the evaluated samples did not induce apoptosis cells, however, ethanolic extract, hexane fraction and rutin promoted changes in the cell morphology. However, hexanic fraction, subfractions 6 and 7 showed the ability to fragment DNA from cells. The fractionation of the ethanolic extract favored the cytotoxic potential, with the hexane fraction being the most promising, and the antioxidant capacity was also favored, with group 5 being the most promising. These results suggest that A. glabra samples have low cytotoxic potential, and the mechanism involved is not related to the induction of apoptosis, and the ethanolic extract contains substances with antioxidant capacity.
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Análise de investimentos para implantação de unidade industrial de pequeno porte de refrigerantes de acerolaRocha, José Vitor da Costa [UNESP] 27 September 2006 (has links) (PDF)
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rocha_jvc_me_botfca.pdf: 649636 bytes, checksum: 10ba83687bf497762253734eace152ec (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O presente trabalho teve por objetivo a análise de investimentos para implantação de unidade industrial de pequeno porte de refrigerante de acerola, planejada para ser instalada no município de Bauru - SP, onde existe um empresário potencial investidor. O mercado brasileiro de refrigerantes tem obtido crescimento considerável, e o grande potencial de consumo deste mercado tem propiciado o surgimento de pequenas indústrias de refrigerantes. Potencial que coloca o Brasil em 3º lugar no consumo de refrigerantes, apenas atrás dos Estados Unidos e México. A acerola que é uma fruta de sabor agradável e rica em vitamina C tem despertado interesse crescente no consumidor brasileiro e apresenta uso potencial como matéria-prima na produção de refrigerante. Para analisar a viabilidade econômica de uma indústria de refrigerantes de pequeno porte, utilizou-se como referência uma capacidade de produção de 300.000 litros/mês. Foram calculados os custos de implantação e os custos de operação da unidade industrial. Para determinação das receitas foram utilizados dois cenários ao longo de um ano de produção. No cenário 1, admite-se a produção constante de 300.000 litros de refrigerante por mês, sendo que no período de entressafra (maio a julho) diversificou-se a produção, com a produção de 30% (90.000 litros) de refrigerante de acerola e 70% (210.000 litros) de refrigerante de guaraná. Já no cenário 2, admite-se que no período de entressafra da acerola, o consumo de refrigerantes apresenta uma redução de 20%, passando para uma produção de 240.000 litros/mês, sendo 72.000 litros de refrigerante de acerola e 168.000 litros de refrigerante de guaraná. Sobre os fluxos de dispêndios e receitas foram determinados os indicadores de viabilidade econômica do projeto, que são: payback simples e econômico; valor presente líquido... / The aim of the present study is to analyze investments for the installation of a small-sized industry of acerola soft drink, planned to be installed in the county of Bauru - São Paulo - Brazil where there is a potential investor. The Brazilian market of soft drinks has had considerable growth and its great potential has made many small industries emerge. This potential puts Brazil in 3rd place in soft drinks consume, only behind United States and Mexico. Acerola which is a tasty fruit and rich in vitamin C has caught Brazilian continuing interest and presents potential use as prime matter in the production of soft drinks. To analyze economic viability of a small-sized soft drink industry, a production capacity of 300,000 liters per month has been used as reference. Installation and factory operation costs have been calculated. Two scenarios along one year of production have been used to determine budget revenues. In scenario 1, the constant production of 300,000 liters per month has been admitted, the off season (May to July) production being diversified with 30% (90,000 liters) acerola soft drinks and 70% (210,000 liters) guarana soft drinks. In scenario 2, acerola off season presents a 20% reduction in the consume of soft drinks, lowering to a 240,000 liters per month production, 72,000 liters of acerola and 168,000 liters of guarana. Over the flow of 4 expenses and revenues, the project indicators of economic viability were determined, which are: simple and economic payback; liquid present value; intern feedback rate and cost benefit relation. The opportunity cost of the capital was 20%. The results obtained through economic viability indicators for both scenarios were favorable to the industry installation. Scenario 1 was more favorable than scenario 2 due to not considering the lower consume in the off-season. The investment analysis for the installation... (Complete abstract, click electronic access below)
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Análise da estabilidade termo-oxidativa do biodiesel de soja na presença de antioxidantes naturais obtidos por diferentes técnicas de extração / Analysis of the thermo-oxidative stability of soybean biodiesel in the presence of natural antioxidants obtained by different extraction techniquesSantos, Ana Claudia Cabral dos 05 December 2014 (has links)
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Previous issue date: 2014-12-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biodiesel is a fuel that can be obtained from renewable sources and due to its chemical composition is sensitive to oxidation. To increase their oxidative stability is necessary to add antioxidants, which are compounds capable of avoiding or delaying oxidation reactions and can be synthetic or natural, from the natural, we highlight a variety of plants with antioxidant activity, among them the mint (Mentha spicata L.) and Acerola (Malpighia glabra L.). The objective of this study was to evaluate the oxidative stability of biodiesel in the presence of natural antioxidants from extracts of Acerola and mint leaves obtained by conventional extraction and supercritical CO2 on temperature and various pressure using oxidative stability in Rancimat test, avaliou- is also the synthetic antioxidant TBHQ, to compare the results obtained with the use of the plant extracts. The effects of temperature and pressure on the yield and quality of the extract. The best induction times were obtained for biodiesel plus the supercritical extracts of Acerola 40 °C and 150 bar condition (1.38 h) and 60 °C and 250 bar (1.07 h) and the supercritical extract of mint conditions of 40 °C and 150 bar (1.08 h), 40 °C and 250 bar (1.71 h) and 60 °C and 250 bar (2.04 h) and soxhlet extract with hexane obtained from both acerola (2.84 h) and Mint (2.87 h), which showed greater induction time of the control (1.04 h). Biodiesel plus the synthetic antioxidant TBHQ got time higher induction to control and biodiesel plus extracts and from 36.95 hours. The oxidative stability of biodiesel was more increased when the extracts obtained by conventional extraction using Hexane as the solvent, which can be extracted from a larger quantity of compounds with antioxidant activity. / Biodiesel é um combustível que pode ser obtido de fontes renováveis e devido sua composição química é sensível à oxidação. Para aumentar sua estabilidade oxidativa é necessário acrescentar antioxidantes, que são compostos capazes de evitar ou retardar reações de oxidação e podem ser sintéticos ou naturais, dentre os naturais, destacam-se uma variedade de plantas com atividade antioxidante, dentre elas a Hortelã (Mentha spicata L.) e Acerola (Malpighia glabra L.). O objetivo deste trabalho foi avaliar a estabilidade oxidativa do Biodiesel na presença de antioxidantes naturais dos extratos das folhas de Acerola e Hortelã obtidos por extração convencional e com CO2 supercrítico em condições de temperatura e pressão variadas, utilizando teste de estabilidade oxidativa em Rancimat, avaliou-se, também, o antioxidante sintético TBHQ, para comparar com os resultados obtidos com a utilização dos extratos das plantas. Foram avaliados os efeitos da temperatura e Pressão no rendimento e da qualidade do extrato. Os melhores tempos de indução obtidos foram para o Biodiesel acrescido dos extratos supercríticos da Acerola nas condições 40 °C e 150 bar (1,38 h) e 60 °C e 250 bar (1,07 h) e os extratos supercríticos da Hortelã nas condições de 40 °C e 150 bar (1,08 h), 40 °C e 250 bar (1,71 h) e 60 °C e 250 bar (2,04 h) e os extratos soxhlet obtidos com hexano, tanto da Acerola (2,84 h) quanto da Hortelã (2,87 h), que apresentaram tempo de indução maior que o controle (1,04 h). O Biodiesel acrescido do antioxidante sintético TBHQ obteve tempo de indução superior ao controle e ao biodiesel acrescidos dos extratos, sendo de 36,95 horas. A estabilidade oxidativa do Biodiesel foi superior quando acrescido dos extratos obtidos por extração convencional utilizando Hexano como solvente, que, pode ter extraído uma maior quantidade de compostos com atividade antioxidante.
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Análise de investimentos para implantação de unidade industrial de pequeno porte de refrigerantes de acerola /Rocha, José Vitor da Costa, 1967- January 2006 (has links)
Orientador: Angelo Catâneo / Banca: Waldemar Gastoni Venturini Filho / Banca: Sergio Augusto Lunardelli Furchi / Resumo: O presente trabalho teve por objetivo a análise de investimentos para implantação de unidade industrial de pequeno porte de refrigerante de acerola, planejada para ser instalada no município de Bauru - SP, onde existe um empresário potencial investidor. O mercado brasileiro de refrigerantes tem obtido crescimento considerável, e o grande potencial de consumo deste mercado tem propiciado o surgimento de pequenas indústrias de refrigerantes. Potencial que coloca o Brasil em 3º lugar no consumo de refrigerantes, apenas atrás dos Estados Unidos e México. A acerola que é uma fruta de sabor agradável e rica em vitamina C tem despertado interesse crescente no consumidor brasileiro e apresenta uso potencial como matéria-prima na produção de refrigerante. Para analisar a viabilidade econômica de uma indústria de refrigerantes de pequeno porte, utilizou-se como referência uma capacidade de produção de 300.000 litros/mês. Foram calculados os custos de implantação e os custos de operação da unidade industrial. Para determinação das receitas foram utilizados dois cenários ao longo de um ano de produção. No cenário 1, admite-se a produção constante de 300.000 litros de refrigerante por mês, sendo que no período de entressafra (maio a julho) diversificou-se a produção, com a produção de 30% (90.000 litros) de refrigerante de acerola e 70% (210.000 litros) de refrigerante de guaraná. Já no cenário 2, admite-se que no período de entressafra da acerola, o consumo de refrigerantes apresenta uma redução de 20%, passando para uma produção de 240.000 litros/mês, sendo 72.000 litros de refrigerante de acerola e 168.000 litros de refrigerante de guaraná. Sobre os fluxos de dispêndios e receitas foram determinados os indicadores de viabilidade econômica do projeto, que são: "payback" simples e econômico; valor presente líquido... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the present study is to analyze investments for the installation of a small-sized industry of acerola soft drink, planned to be installed in the county of Bauru - São Paulo - Brazil where there is a potential investor. The Brazilian market of soft drinks has had considerable growth and its great potential has made many small industries emerge. This potential puts Brazil in 3rd place in soft drinks consume, only behind United States and Mexico. Acerola which is a tasty fruit and rich in vitamin C has caught Brazilian continuing interest and presents potential use as prime matter in the production of soft drinks. To analyze economic viability of a small-sized soft drink industry, a production capacity of 300,000 liters per month has been used as reference. Installation and factory operation costs have been calculated. Two scenarios along one year of production have been used to determine budget revenues. In scenario 1, the constant production of 300,000 liters per month has been admitted, the off season (May to July) production being diversified with 30% (90,000 liters) acerola soft drinks and 70% (210,000 liters) guarana soft drinks. In scenario 2, acerola off season presents a 20% reduction in the consume of soft drinks, lowering to a 240,000 liters per month production, 72,000 liters of acerola and 168,000 liters of guarana. Over the flow of 4 expenses and revenues, the project indicators of economic viability were determined, which are: simple and economic payback; liquid present value; intern feedback rate and cost benefit relation. The opportunity cost of the capital was 20%. The results obtained through economic viability indicators for both scenarios were favorable to the industry installation. Scenario 1 was more favorable than scenario 2 due to not considering the lower consume in the off-season. The investment analysis for the installation... (Complete abstract, click electronic access below) / Mestre
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Estudos farmacognósticos, fitoquímicos e biológicos de Annona glabra L. (Annonaceae)BRÍGIDO, Heliton Patrick Cordovil 12 May 2016 (has links)
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Previous issue date: 2016-05-12 / No presente trabalho, a Annona glabra foi submetida a estudos farmacognósticos, fitoquímicos e biológicos (atividade leishmanicida e antimicrobiana). Nos estudos farmacognósticos, utilizou-se os métodos descritos na Farmacopéia Brasileira V ed. (2010). O extrato etanólico (EE) foi obtido através de maceração descontínua do pó das cascas com etanol. Este foi submetido a fracionamento por partição líquido-líquido com hexano e metanol aquoso 10%, gerando-se as frações hexanica (FH) e metanólica (FM). A FM foi refracionada em coluna de Sephadex originando-se 46 frações, analisadas em CCD e reveladas com ácido Sulfúrico, Dragendorff e ultravioleta (360 nm) sendo reunidas em 5 grupos conforme o perfil cromatográfico. O Grupo 3 foi purificado em coluna cromatográfica em escala preparativa originando a amostra G3-1. O EE, FM, FH, Grupo 2 e G3-1 foram analisadas em CLAE-DAD. A amostra G3-1 foi submetida a análise em espectroscopia de massas e ressonância magnética nuclear (RMN). Na avaliação da atividade antimicrobiana utilizou-se os métodos da difusão em ágar (Escherichia coli, Staphylococcus aureus e Pseudomonas aeruginosa) e de microdiluição (CIM). O EE e suas frações foram submetidos ao ensaio da atividade leishmanicida (Leishmania amazonensis). O pó foi classificado como pó grosso e de baixa densidade com teor de cinzas e umidade estando dentro dos parâmetros estabelecidos pela Farmacopéia Brasileira. Em CLAE-DAD, os principais picos do EE e suas frações apresentaram no espectro de UV absorbâncias com ʎ entre 240 nm a 280 nm e ʎ entre 300 nm a 400 nm sugestivos respectivamente da banda II (anel A) e banda I (anel B) de flavonóides. A estrutura química de G3-1 foi identificada como sendo o flavonóide Rutina. No teste de difusão em ágar observou-se a formação de halos do EE e FM somente nas placas de Staphylococcus aureus. No ensaio de microdiluição verificou-se que o EE e a FM apresentaram CIM>1000 μg/mL, sendo assim, consideradas inativas. No ensaio antileishmania, o EE apresentou CI50>200 μg/mL. A FM e FH também apresentaram CI50>200 μg/mL, no entanto, inibiram o crescimento das promastigotas respectivamente em 20% e 33,7%. As subtrações Grupo 2 e G3-1 apresentaram CI50>200 μg/mL, porém, na concentração de 200 μg/mL inibiram o crescimento parasitário em aproximadamente 45%. O EE, suas frações e subfrações foram inativas frente as amastigotas de L. amazonensis, no entanto, a FH nas concentrações de 250 e 125 μg/mL inibiu a infecção em 39,1% e 18,7%. Em síntese, o EE e suas frações mostraram-se inativas nos ensaios antimicrobiano e leishmanicida, porém o fracionamento contribuiu para o aumento da atividade sugerindo que substâncias ativas devam estar em baixos teores no extrato e suas frações. / In this study, the Annona glabra underwent pharmacognostic, phytochemicals and biological studies (leishmanicide and antimicrobial activity). In pharmacognostic studies, we used the methods described in Brazilian Pharmacopoeia V ed. (2010). The ethanolic extract (EE) was obtained by maceration of the powder batch of shells with ethanol. The extract was fractionated by liquid-liquid partition with hexane and 10% aqueous methanol resulting in hexane (HF), and methanol (MF) fractions. The MF was submitted to Sephadex column. This procedure resulted in 46 fractions that were analyzed in thin layer chromatography and revealed with sulfuric acid, Dragendorff, and ultraviolet (360 nm) being assembled into 5 groups according to their chromatographic profiles. Group 3 was purified by column chromatography on a preparative scale yielding the G3-1 sample. EE, MF, HF, Group 2 and G3-1 were analyzed by HPLC-DAD. The G3-1 sample was analysed by mass spectrometry and nuclear magnetic resonance (NMR). To evaluate the antimicrobial activity, methods of agar diffusion (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) and microdilution (MIC) were used. The EE and its fractions were subjected to leishmanicide activity test (Leishmania amazonensis). The powder was classified as coarse and low-density, with ash and moisture contents within the parameters established by the Brazilian Pharmacopoeia. In HPLC-DAD, the main peaks of EE and its fractions were presented in UV absorption spectrum of 240 nm to 280 nm, and 300 nm to 400 nm suggestive respectively Band II (Ring A), and band I (ring B ) of flavonoid. The G3-1 chemical structure was identified as flavonoid rutin. In the agar diffusion test, we observed the formation of halos in EE and MF only in Staphylococcus aureus plates. In the microdilution assay, the EE and FM showed MIC> 1000 mg / mL, considered inactive. In antileishman test, the EE showed IC50> 200 / ml. The MF and HF also showed IC50> 200 / ml; however, they inhibited the growth of promastigotes respectively in 20% and 33.7%. The subtractions and G3-1 Group 2 showed IC50> 200 / ml, but the concentration of 200 / ml inhibited the parasite growth by approximately 45%. The EE, fractions, and subfractions were inactive against L. amazonensis amastigotes. However, the HF concentrations of 250 and 125 g / ml inhibited infection in 39.1% and 18.7%. In short, EE and its fractions were shown to be inactive in the antimicrobial and leishmanicide trials, but fractionation contributed to increase activity suggesting that active substances must be at low levels in extract and its fractions.
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Life-history consequenses of host plant choice in the comma butterflySöderlind, Lina January 2012 (has links)
There is much evidence that herbivory is a key innovation for the tremendous success of insect. In this thesis I have investigated different aspects of host plant utilization and phenotypic plasticity using the polyphagous comma butterfly, Polygonia c-album. Even though external conditions affect a phenotypic plastic response, the outcome is often influenced by a genetic background which may differ among populations. In Paper I we suspected the genetic background to seasonal polymorphism to be X-linked. However, results from interspecific hybridization between two populations suggested that diapause response is instead inherited in a mainly autosomally additive fashion, with a possible influence of sexual antagonism on males. In Paper II we showed that female oviposition preference is not a plastic response influenced by larval experience, but has a genetic background coupled to host plant suitability. Further, there is a strong individual correlation between larval host plant acceptance and female host plant specificity (Paper III). We believe this to be a larval feed-back genetically linked to female host specificity: offspring to ‘choosy’ specialist mothers benefit by remaining on the original host while offspring to less discriminating generalist mothers should risk inspecting the surroundings, thus compensating for potential poor female choice. In the larval mid-gut, genes are differentially expressed depending on host plant diet (Paper IV). Therefore, we expected to find fitness consequences of host plant switch. However, although growth rate was affected in a few treatments, larvae were generally surprisingly good at adjusting to new diets (Paper V). To conclude, host plant choice in both female and larval life stage is connected to performance. Combined with increased understanding about the plastic response to diet intake and seasonal polymorphism we have gained further insights into the processes of local adaptations and speciation in the Lepidoptera. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted Manuscript; Paper 5: Manuscript
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Antimicrobial plants of Australia have the potential to prevent lactic acidosis in ruminantsHutton, Peter January 2008 (has links)
[Truncated abstract] Antimicrobial growth promoters are added to feed to prevent lactic acidosis in ruminant animals by selectively inhibiting rumen bacteria that produce lactic acid. However, recently imposed or impending bans on the use of antimicrobial growth promoters in animal production have lead to a critical need to find practical alternatives that are safe for the animal and consumer and that obtain similar production benefits. I investigated bioactive plants of Australia for their potential to prevent lactic acidosis in ruminants. The unifying hypothesis tested was that plants would be identified that selectively inhibit lactic acid-producing bacteria and consequently protect against lactic acidosis. This hypothesis was tested in a three phase process: phase 1, plant selection and collection; phase 2, a three stage protocol for screening plants and essential oils; phase 3, in vivo experiments and chemical fractionation of the most promising plant. I developed an in vitro bioassay that simulated acidosis by adding glucose to rumen fluid in Bellco tubes and incubating for 5 h (Chapter 4). The pH and gas production were used as indicators of acidosis and fermentation activity. I used this bioassay to screen ninety-five plants (dried and ground material from 79 species) and ten essential oils and included a negative control (oaten chaff) and a positive control (virginiamycin). One plant, Eremophila glabra, produced a similar pH (5.63) to the positive control (5.43) although it inhibited gas production to a moderate extent (P < 0.05). ... Seven serrulatane diterpenes were identified to be the major secondary metabolites in E. glabra. The metabolites were screened using a broth dilution and microtitre spectrophotometry method and were selective against S. bovis at between 320 and 1077 [mu]g/ mL. The serrulatanes from E. glabra were probably responsible for the activity against acidosis that I observed in vitro, because they selectively inhibited lactateproducing bacteria. It is also possible that a synergy between serrulatanes and possibly other metabolites are responsible for the activity observed in vitro. The results from my experiments support the role that bioactive plants may have to replace the antibiotics that are added to livestock feed. Australian plants were identified containing compounds that were active against the bacterial processes responsible for ruminant acidosis. To my knowledge this is the first work undertaken to identify bioactive plants of Australia for their potential to prevent acidosis. I developed in vitro screening bioassays that targeted key indicators of acidosis. These bioassays enabled me to identify 5 plants from the 104 screened that could potentially control acidosis. One of these plants in particular, E. glabra, showed a level of activity in vitro that was comparable to antibiotic protection against acidosis. The exciting in vitro results were not demonstrated in vivo but only one dose level of E. glabra was used, which was based on the in vitro work. In contrast to the in vitro system the rumen is a continuous flow system with greater complexity and it is possible that the concentration of E. glabra that I used in vivo was not optimum. This places importance on future dose response experiments to confirm the efficacy of E. glabra in vivo.
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An investigation of compounds isolated from Glycyrrhiza Glabra (Liquorice root)Raubenheimer, Carike 10 1900 (has links)
Introduction: Dark spots appearing on the skin caused by hyperpigmentation results from the action of tyrosinase, an enzyme whose activity leads to the production of the skin pigment melanin. Extracts of the plant Glycyrrhiza glabra, also known as liquorice, are commonly used to treat a range of conditions including skin hyperpigmentation. This study aimed at isolating and identifying compounds in extracts from South African liquorice root and assaying these compounds as to their antioxidant activity, their ability to inhibit the tyrosinase enzyme and their level of cytotoxicity.
Methods: The ability of plant extracts to scavenge free radicals was tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonicacid)] (ABTS) and the ferric ion reducing power (FRAP) tests. The polyphenolic content of extract fractions was determined and extract compounds were identified using UHPLC-QToF-20 MS. In vitro anti-tyrosinase activity was also investigated as well as cytotoxicity in HepG2 liver and SK-MEL-1 melanoma cells using the MTT cell viability assay.
Results: Of the four fractions prepared from the 70% methanolic extract of liquorice root, fraction 3 (F3) showed increased polyphenolic content and antioxidant properties with IC50 of 56.1 ± 6.32, 39.14 ± 1.1 and 66.34 ± 1.4 μg/ml against DPPH, ABTS and FRAP, respectively. The anti-tyrosinase activity of this fraction showed an IC50 of 358.54 μg/ml compared to Kojic acid (0.75 mM) used as the control. In addition, this fraction showed reduced liver toxicity as a higher percentage cell viability was noted in the HepG2 cells compared to the SK-MEL-1 skin melanoma cells. However, both cell types showed higher percentage viability compared to acetaminophen that was used as cytotoxic control. The LC-MS analysis revealed the presence of a wide variety of compounds including 4-azido-3-benzyl-coumarin, ferulic acid, glycyrrhizin, quercitrin, cirsilineol, gentioflavine and 4'',6,7-trihydroxyisoflavone. The literature indicates the use of these compounds regarding antioxidant and anti-tyrosinase activity. Significantly, cularidine was identified in this study, a compound not previously reported in studies involving liquorice root.
Conclusion: The results from this study concur with previous reports as to the anti-tyrosinase and antioxidant activities associated with liquorice roots, activities perhaps due to the relatively high polyphenolic content in extracts from South African liquorice root. / Life and Consumer Sciences / M. Sc. (Life Sciences)
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