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Isolation and identification of poisonous triterpenoids from Elaeodendron croceumYelani, Thembela 14 September 2010 (has links)
Various plant species have been reported traditionally as well as in scientific literature for cytotoxicity against animal species. Isolation of several poisonous compounds from plant species has been reported previously. Elaeodendron croceum is a well-known poisonous plant species of which the poisonous compounds have not yet been isolated. A phytochemical investigation of E. croceum leaves guided by cytotoxicity against Vero cells, led to the isolation of five known compounds; 20-hydroxy-20-epi-tingenone (1), tingenone (2), tingenine B (3), 11α-hydroxy-β-amyrin (4), and naringenin (5). Compounds 1 and 2 showed the highest toxicity against Vero cells (IC50: 2.651 nM and 8.233 μM respectively). Cytotoxicity of the isolated compounds against three human cancer cell lines, HeLa, MCF-7, and SNO was also determined. Compounds 1 and 2 again showed the highest cytotoxicity with IC50 values ranging between 2.478 – 0.427 μM. This is the first report on the isolation, identification, and in vitro evaluation of poisonous compounds from E. croceum. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted
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Development of Methods for Analysis of Valuable Compounds in By-products from Agricultural and Forestry Industrial SectorsFridén, Mikael E January 2015 (has links)
A growing interest in sustainable development has made efficient utilisation of starting materials and, if they occur, by-products become increasingly important. Vast amounts of by-products are generated by the forestry and food industry. Incineration for energy production is one way to make use of these by-products but some of them contain compounds that would have an increased value if they were extracted, so called “high value species”. The by-products are often very complex, so reliable methods for analysis of the high value species are required in the development of processes to utilise them. A wide range of compounds can be analysed using chromatographic separation coupled to mass spectrometry, making it a powerful tool in the evaluation of methods for extracting high value species from industry by-products. This thesis is based on four studies of potential high value species. In the first study, methods were developed to differentiate isobaric flavonoids and then use this knowledge to determine the identity of the flavonoids in three different plant extracts. In the second study, three different methods to extract betulin from birch bark were evaluated regarding extracted amount and purity of betulin. One of the methods was then investigated in industrial scale using a model approach. In the third study, the flavonoid contents of lovage were determined and other major extracted compounds were investigated by high performance liquid chromatography coupled to electrospray ionisation mass spectrometry. Gas chromatography and supercritical fluid chromatography were used to obtain complementary information about major components. In the fourth study, high resolution mass spectrometry utilising two different types of fragmentation was used with the purpose of overcoming the shortcomings of the methods developed in the first study. The results indicated that it would be possible to develop methods compatible with chromatographic separation for differentiating different types of isobaric substituents. The ability of performing sequential fragmentation was used to investigate some isobaric aglycones by creating spectral trees, and unique pathways were found for each of them.
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Antidiabetic activity of pentacyclic triterpenes and flavonoids isolated from stem bark of Terminalia sericea Burch.Ex DCNkobole, Nolitha Khanya 21 October 2009 (has links)
Diabetes mellitus (DM) represents a series of metabolic conditions associated with hyperglycemia and caused by defects in insulin secretion, and/ insulin action. Exposure to chronic hyperglycemia may result in microvascular complications in the retina, kidney or peripheral nerves. According to the World Health Organization (WHO) global burden of disease, more than 176 million people are diabetic with about two thirds of these living in developing countries. With a long course and serious complications that often result in high incidences of mobility and mortality rate, the treatment of diabetes is often costly. The management of this disease is not without side effects and this is a challenge to the medical system. This has led the researches to seek new antidiabetic agents from plants. Acetone extract of 8 plants namely Terminalia sericea Burch. Ex DC, Euclea natalensis A.DC, Warbugia salutaris Bertol.f.) Chiov., Artemisia afra Jacq.ex Willd., Aloe ferox Mill, Sclerocarya birrea (A.Richi.) Hochst. subsp. caffra , Spirostachys Africana Sond and Psidium guajava L were evaluated for antidiabetic and antioxidant properties. In addition extracts were tested for cytotoxicity. Different parts of all these plants are traditionally used in South Africa for diabetes treatment. Plants were selected based on ethnobotanical information and phytochemical constituents. For determining inhibitory activity against each enzyme (α-glucosidase and α- amylase), all extracts were tested at concentration that ranged from 2x10-5 to 0.2mg/ml for α-glucosidase and 0.025 to 1.25mg/ml for α-amylase and fifty percent inhibition or higher was taken as significant (p<0.05). The extracts of A. ferox and S. africana showed no inhibition against α-glucosidase at the highest concentration tested (0.2mg/ml) whereas A. afra showed weak inhibition (47.15%). T. sericea showed to be a potent inhibitor of α-glucosidase exhibiting 97.44 % inhibition of the enzyme (p<0.05). W. salutaris, S birrea and E. natalensis also showed good activity on α-glucosidase as they demonstrated 71.84; 97.44 and 92.60 % inhibition respectively (p<0.05). Other plant extracts such as A. ferox and S. africana did not exhibit any activity on α-glucosidase. T. sericea and S. birrea showed the best inhibitory activity on α-amylase enzyme, exhibiting 91.91 and 94.94 % inhibition respectively at 1.25mg/ml. A. afra, E. natalensis, P. guajava and W. salutaris also showed good inhibitory activity on -amylase enzyme at 1.25mg/ml which was the highest concentration tested (p<0.05). Low levels of plasma antioxidants is a risk factor associated with diabetes therefore, it has been suggested that plant-based medicines that contain antioxidant properties add an advantage in curbing complications that arise during DM aetiology. The antioxidant activity of plant extracts was carried out using 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) assay. Six plant extracts which showed good α-glucosidase and α-amylase inhibitory activity were evaluated for antioxidant activity. The radical scavenging activity was measured in terms of the amount of antioxidants necessary to decrease the initial DPPH absorbance (EC50). The EC50 is the amount of antioxidants necessary to decrease initial DPPH absorbance by 50%. All 6 tested plant extracts showed good activity. W. salutaris and T. sericea demonstrated the highest activity exhibiting EC50 values of 5.08 and 5.56βg/ml respectively as compared to ascorbic acid/Vitamin C (EC50=2.52μg/ml), a well- known potent antioxidant. This was followed by P. guajava (EC50=6.97μg/ml); E. natalensis (EC50=8.46μg/ml) and S. birrea (EC50=9.41μg/ml). A. ferox showed EC50 value of 48.53μg/ml. It has been suggested that plant extracts and compounds must undergo toxicity test for safety before drug discovery is taken into consideration. Due to the large number of plants screened in this study and limited resources in our laboratory, only the acetone extract of T. sericea (which demonstrated good α-glucosidase and -amylase inhibitory activities) was tested for cytotoxicity. Acetone extract of T. sericea demonstrated moderate toxicity against primary vervet monkey kidney cells (VK) cells exhibiting IC50 values of 20.94 μg/ml when tested at 400μg/ml. Consequently, the acetone extract of T. sericea was selected for the isolation and identification of bioactive compounds. A bio-assay guided fractionation of the acetone extract of T. sericea led to the isolation of 4 pure compounds namely β-sitosterol, β-sitosterol-3-acetate, lupeol and 3-onestigmasterol and two sets of mixtures of isomers (epicatechin-catechin; MI1 and epigallocatechingallocatechin; MI2). Antidiabetic, antioxidant and cytotoxicity activities of isolated compounds were evaluated. μ–Sitosterol and lupeol showed best inhibitory activity on α-glucosidase exhibiting 50% inhibitory concentration (IC50) value of 54.50 μM and 66.48 μM respectively (p<0.05). This was followed by the MI2; epigallocatechin-gallocatechin (IC50=119.34 μM); β-sitosterol-3-acetate (IC50=129.34 μM); 3-one-stigmasterol (IC50=164.87 μM) and the MI1; epicatechin-catechin (IC50=255.76 μM). During the evaluation of purified compound’s inhibitory activity on α-amylase, compounds of interest were lupeol and β-sitosterol which exhibited IC50 values of 140.72 μM and 216.02 μM respectively as compared to the positive drug-control acarbose (IC50=65.25 μM). Epicatechincatechin and epigallocatechin-gallocatechin also demonstrated α-amylase inhibitory properties and the IC50 values were found to be lower than 100μg/ml. Epigallocatechin-gallocatechin, epicatechin-catechin and lupeol showed good free radical scavenging activity as they inhibited DPPH by 98.19; 96.98 and 70.90 % at 100ìg/ml respectively (p<0.05). The DPPH scavenging activity was very low in case of 3-one-stigmasterol (21.5% inhibition), whilst β-sitosterol and its derivative β-sitosterol-3-acetate did not show any activity. During cytotoxicity evaluation of pure compounds against monkey kidney cells, all the compounds except β-sitosterol did not inhibit the growth of these cells lines at the highest concentration tested (200μg/ml). β-Sitosterol showed moderate toxicity exhibiting IC50 values of 197.72 μM. β- Sitosterol-3-acetate, epicatechin-catechin, lupeol and epigallocatechin-gallocatechin were found to be non-toxic to Vero cells as 100% cell viability was observed when Vero cells were exposed to these samples at 200μg/ml. The compounds isolated and the extract of T. sericea demonstrated significant antidiabetic and antioxidant properties as compared to well known drugs acarbose (a known -glucosidase and α- amylase inhibitor) and Vitamin C (a well known antioxidant). This study is the first to report α- glucosidase, α-amylase and antioxidant properties of epicatechin-catechin, epigallocatechingallocatechin, β-sitosterol-3-acetate and stigma-4-ene-3-one isolated from T. sericea. In addition, epicatechin-catechin, epigallocatechin-gallocatechin, β-sitosterol-3-acetate and stigma-4-ene-3-one are isolated from T. sericea for the first time. Overall all results scientifically validated the traditional use of the bark of T. sericea for diabetes in South Africa. / Dissertation (MSc)--University of Pretoria, 2011. / Plant Science / unrestricted
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Total Synthesis Of Sesquiterpenes Acorenols, Chamigrenes And Laurokamurene B; And Enantiospecific Synthesis Of ABC-Ring System Of A-Nor And Abeo Pentacyclic TriterpenesBabu, R Ramesh 10 1900 (has links)
Among Nature’s creation, terpenoids are more versatile and exciting natural products. In a remarkable display of synthetic ingenuity and creativity, nature has endowed terpenes with a bewildering array of carbocyclic frameworks with unusual assemblage of rings and functionalities. This phenomenal structural diversity of terpenes make them ideal targets for developing and testing new synthetic strategies for efficient articulation of carbocyclic frameworks. The thesis entitled “Total synthesis of sesquiterpenes acorenols, chamigrenes, and laurokamurene B; and Enantiospecific synthesis of ABC-ring system of A-nor and abeo pentacyclic triterpenes” describes the studies directed towards the total synthesis of the sesquiterpenes mentioned in the title and exploratory studies towards triterpenoids. In each chapter of the thesis, the compounds are sequentially numbered (bold) and references are marked sequentially as superscripts and listed at the end of the chapter. All the spectra included in the thesis were obtained by xeroxing the original NMR spectra.
The sesquiterpenes acorenols, containing an interesting spiro[4.5]decane carbon framework, was first isolated in 1970 by the research group of Tomita from the wood of Juniperus rigida. Recently, in 2003, Braun and coworkers reported the isolation of epi α- and epi β-acorenols along with α- and β-acorenols from the sandal wood oil Santalum spicatum. Total synthesis of all the four acorenols has been described in the first part of the first chapter of the thesis. Initially, a model study has been carried out for the spirocyclopentannulation of cyclohexanone employing a combination of Ireland ester Claisen rearrangement and ring closing metathesis reaction to furnish methyl 4-methylspiro[4.5]dec-3-en-1-carboxylate. The same methodology has been extended for the total synthesis of all the four acorenols starting from cyclohexane-1,4-dione via cis and trans isomers of methyl 4-methyl-8-methylene-spiro[4.5]dec-3-ene-1-carboxylate.
Total synthesis of β-chamigrene, γ-chamigrene and laurencenone C, containing spiro[5.5]undecane carbon framework, has been described in the second part of the first chapter. As a model study, cyclohexanone has been transformed into 1,5,5-trimethylspiro-[5.5]undec-4-en-3-one employing a combination of Ireland ester Claisen rearrangement and intramolecular type-II carbonyl ene reactions. The methodology has been extended to
chamigrenes starting from cyclohexane-1,4-dione via methyl 2-(1-isopropenyl-4-oxocyclo-hexyl)-2-methylpropanoate and 5,5-dimethyl-1,9-ismethylenespiro[5.5]undecan-3-ol.
The marine sesquiterpenes laurokamurenes were first isolated in 2006 by Mao and Guo from Laurencia okamurai Yamada. First total synthesis of (±)-laurokamurene B has been described in the first part of the second chapter. To begin with Ireland ester Claisen rearrangement of but-2-enyl 2-methylpropionate furnished methyl 2,2,3-trimethylpent-4-enoate, which was then transformed into 4,5,5-trimethyl-3-(4-methylphenyl)hepta-1,6-dien-3-ol. RCM reaction followed by reductive deoxygeneation transformed 4,5,5-trimethyl-3-(4-methylphenyl)hepta-1,6-dien-3-ol into (±)-laurokamurene B. Subsequently, an enantioselective total synthesis of (+)-laurokamurene B has been accomplished. Stereoselective hydrogenation of methyl campholenoate furnished methyl 2-[(1S,3S)-2,2,3-trimethyl-cyclopent-1-yl]acetate, which was then transformed into (+)-laurokamurene B via degradation of the two carbon side chain and introduction of the aryl moiety, which established the absolute configuration of laurokamurenes.
The third chapter deals with the enantiospecific generation of ABC-ring system of A-nor and abeo 4(3 → 2) tetra and pentacyclic triterpenes. To begin with (R)-carvone was identified as B-ring of ABC-ring system of A-nor and abeo tetra and pentacyclic triterpenes, as the absolute configuration at the C-5 position of the targets correlate to the stereo centre of carvone, and isopropenyl group can serve as the C-4 carbon of the targets along with the two gem-dimethyl groups. A lithium liquid ammonia mediated cyclisation of δ,ε-unsaturated esters was employed for the construction of the A ring and an RCM reaction was opted for the construction of the C ring. (R)-Carvone has been converted into 2-(1-ethoxyethoxy)-1,3,7,7-tetramethylbicyclo[4.3.0]non-3-en-8-ol via lithium liquid ammonia mediated cyclisation of methyl 2-(1-ethoxyethoxy)-6-isopropenyl-1,3-dimethylcyclohex-3-enyl]acetate, which was then transformed into 4-methoxymethoxy-2,5,5,9-tetramethyltricyclo[7.4.0.02,6]tridec-11-en-8-one via the RCM reaction of 3,4-bisallyl-8-methoxymethoxy-4,6,9,9-tetramethylbicyclo-[4.3.0]nonan-3-one. The strategy has been further extended to the synthesis of 4-methylene-2,5,5,9-tetramethyltricyclo[7.4.0.02,6]tridec-11-en-8-one, which contains the ABC ring system of abeo 4(3→2) tetra and pentacyclic triterpenes.
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Estudo dos constituintes quÃmicos de duas amostras de prÃpolis: Alto Santo - Cearà e Passa Quatro - Minas Gerais / Investigations of the chemical constituent of two samples of propolis: one from Alto Santo - Cearà and other from Minas Gerais - BrasilIrineu Lima de Albuquerque 17 August 2007 (has links)
nÃo hà / PrÃpolis, palavra de origem grega e significa a defesa da cidade. Usado na colmÃia para fechar frestas, garantindo a proteÃÃo contra microorganismos. Diversas propriedades foram relatadas terapeuticamente como: bactericida, fungicida, antivÃrus, antiinflamatÃria. As amostras de prÃpolis brasileiras podem ser classificados em 13 grupos, baseados nas caracterÃsticas fÃsico-quÃmicas e classificadas da seguinte maneira: cinco no Sul do Brasil (grupo 3), um no Sudeste (grupo 12) e seis no Nordeste (grupo 7). O trabalho teve como objetivo a investigaÃÃo fitoquÃmica de duas amostras de prÃpolis: uma de Alto Santo - Ceara e outra de Minas Gerais â Brasil, alÃm da determinaÃÃo da atividade biolÃgica e antioxidante. Da amostra de prÃpolis do CearÃ, foram identificados: triterpenos (lupeol, Ãcido canÃrico, lupenona e germanicona); flavonoides (quercetina, canferol, acacetina, 3-(4-metoxifenila) acrilato de 2(E)-2-metoxifenila-5-(5-hidroxi-3,7-dimetoxi-4-oxo-4H-cromen-2-ila). Da prÃpolis de Minas Gerais popularmente chamada de prÃpolis verde, obteve-se: Ãcido p-cumaric, Ãcido (E)-3-(3,4-dihidroxifenila) propenÃico e uma mistura dos Ãcidos: Ãcido (E)-3-(4-hidroxifenila) propenÃico, Ãcido 3-phenilpropanÃico e Ãcido 3-(4-hidroxifenila) propanÃico. Do lupeol obteve-se uma sÃrie de derivados, entre eles: o produto oxidado e os Ãsteres no carbono-3. Os compostos e os derivatives puros do lupeol foram identificados por mÃtodos espectroscÃpicos tais como IR, o RMN 1H e 13C CG/EM. Extrato de prÃpolis e compostos puros isolados foram avaliados para a atividade antioxidante usando o mÃtodo de captura de radical DPPH (2,2-difenila-1-picril-hidrazila) e os resultados mostraram a atividade muito boa para extratos e para os flavonÃides, os triterpenos mostraram uma atividade pequena. Do Ãleo essencial da prÃpolis de Minas Gerais, identificaram-se os constituintes classificados como monoterpenos oxigenados (0,3%), hidrocarbonetos sesquiterpenos (65,18%), sesquiterpenos oxigenados (23,64%), e derivados do Ãcido cinÃmico (6,17%). Foram identificados 24 constituintes, representando 97,7% do Ãleo, e os compostos principais definidos como: E-nelolidol (17,14%), E-cariofileno (13,38%) e selin-3,7(11)-dieno (10,35%) foram os mais abundantes. O Ãleo foi caracterizado com alta percentagem de hidrocarbonetos sesquiterpenos e sesquiterpenos oxigenados. A partir da prÃpolis de Minas Gerais, material de partida para a produÃÃo de pà liofilizado, produziu-se prÃpolis solÃvel em Ãgua, obtida de uma mistura com soluÃÃo de L-lisina e PVP. O liofilizado terà destino para testes biolÃgicos. / Propolis, word has the Greek origin, and means city defense. Used in the beehive to forbid openings, guaranteeing protection against microorganisms. Several therapeutically properties were reported such as: bactericidal, fungicidal, antivirus, anti-inflammatory. Brazilian propolis can be classified in 13 groups, based on the physical-chemistry characteristics classified as: five in the South of Brazil (group 3), one in Southeast (group 12) and six in the Northeast (group 7). The present work has a goal the phytochemical investigation of two samples of propolis: one from Alto Santo - Cearà and other from Minas Gerais - Brasil and determination of biological activity. From a sample of propolis of CearÃ, were identified: triterpenes (lupeol, acid canaric, lupenone and germanicone); flavonoids (kercetin, kanferol, acacetine, 3-(4-methoxyphenyl) acrilate of 2-(E)-2-methoxyphenil-5-(5-hydroxy-3,7-dimethoxy-4-oxo-4H-cromene-2-il). For the sample propolis of Minas Gerais popularly called âgreen propolisâ were identified p-cumaric acid, (E)-3-(3,4-dihidroxyphenyl) propenoic acid and a mixture of acid ones: (E)-3-(4-hydroxyphenyl) propenoic acid, 3-phenylpropanoic acid and 3-(4-hydroxiphenil) propanoic acid. From lupeol a serie of derivative were obtained including oxidation and esters at carbon-3. Pure compounds and lupeol derivatives were identified by spectroscopic methods such as IR, 1H and 13C NMR and MS. Propolis extracts and pure compounds were evaluated for scavenger activity using DPPH (2,2-diphenyl,1-picril-hidrazil) bioassay and results showed very good activity for extracts and for flavonoids where as triterpens showed a week activity. The essential oil of the propolis from Minas Gerais obtained by hydrodestillation process was analyzed by CG-MS techniques and composition was defined as: oxygenated monoterpenes (0,30%), hydrocarbons sesquiterpenes (65,18%), sesquiterpenes oxigenated (23,64%), and derivatives of the cinamic acid (6,17%). Twenty constituent were identified representing 97.7% and major compound defined as: E-nelolidol (17,14%), E-cariofilene (13,38%) and selin-3,7(11)-dien (10,35%). The oil was characterized with high percentage of hydrocarbons sesquiterpenes and oxygenated sesquiterpenes. The green propolis of Minas Gerais was used as material for the lyophilized drug production. From the propolis water soluble together with L-lysine and a polymer PVP was obtained a power and it is using for biological tests as anticancer agent.
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Glycosidation de triterpènes pentacycliques de type lupane et évaluation in vitro de leur potentiel anticancéreux /Gauthier, Charles, January 1900 (has links)
Thèse (M.Ress.Renouv.) - Université du Québec à Chicoutimi, 2006. / Bibliogr.: f. 86-94. Document électronique également accessible en format PDF. CaQCU
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Derivados poliprenilados de benzofenonas, triterpenos, esteróides, bifenila e xantona de clusia burlemarxii e atividade citotóxica contra células GL-15, de glioblastoma humanoFerraz, Caline Gomes January 2011 (has links)
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Previous issue date: 2011 / CAPES / O presente trabalho relata o estudo fitoquímico do caule da espécie Clusia burlemarxii (Clusiaceae), coletada nas proximidades da Cachoeira do Fraga no município de Rio de Contas e Mucugê na Chapada Diamantina-BA, Do estudo deste extrato permitiu o isolamento, identificação e determinação de seis metabólitos inéditos denominados: isopropolona A, burlemarxionas A, B, C, D e E e dezesseis substâncias conhecidas: as benzofenonas polipreniladas, propolona A, sampsoniona B, sampsoniona N, obdeltifoliona C; os triterpenos, friedelina, friedelinol, ácido betulínico, betulinaldeído, lupeol, eufol e butirospermol; os esteróides, sitosterol, estigmasterol e sitostenona; uma bifenila a 2,2-dimetil-5-hidroxi-7-fenilcromeno e uma xantona a brasilixantona B. A determinação estrutural dos metabólitos secundários isolados foi realizada através de técnicas espectrométricas como: Infravermelho, EM e Ressonância Magnética Nuclear de Hidrogênio-1 e Carbono-13, DEPT, HMBC, HMQC juntamente com comparação dos dados descritos na literatura. As substâncias propolona A, sampsoniona N e burlemarxiona A, tiveram sua citotoxicidade contra Células de Glioblastoma Humano GL-15 avaliada. / Salvador
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Studies on the pharmacological properties of resin from Protium heptaphyllum (Aubl.) March. and its major constituent, alpha-and beta-amyrin mixture / Estudo das propriedades farmacolÃgicas da resina de Protium heptaphyllum (Aubl) March e de seus principais constituintes, mistura de alpha e beta amirinaFrancisco de Assis Oliveira 24 June 2005 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Protium heptaphyllum March (Burseraceae) populary known as âalmÃcegaâ is a popular medicinal plant largely encountered in the Amazon region, various States of Brazil and in several South American Countries. The oily amorphous exudate obtained from this plant is widely used in skin diseases, healing of ulcers, and as an analgesic and anti-inflamatory agent. Phytochemical studies reveled the presence of several monoterpenes and pentacyclic triterpenes such as a mixture of α- e β â amyrin, maniladilol and breine. The present study aimed to investigate the general toxicity and to establish the pharmacological activity of resin and is major triterpenoid mixture, the α and β â amyrin. In toxicity tests, both the resin and triterpene mixture exhibited low toxicity to mice. Resin at doses up 5 g/kg, (p.o.) or 2 g/kg (i.p.) and triterpene mixture up to 3 g/kg, (p.o.) or 2 g/kg (i.p.) failed to induce any mortality in mice. In Artemia-lethality test, the calculated (probit analysis) CL50 values for resin and triterpenes were in the order of 42,54  19,96 and 400  27,85 μg/mL, respectively. In pharmacological tests, the resin was analysed for anti-inflamatory (carrageenan-induced edema, cotton pellet-induced granuloma, and vascular permeability increase induced by i.p. acetic acid) and gastroprotective (absolute ethanol and acidified ethanol) effects, whereas the triterpene mixture was examined in assays that demostrate gastroprotective (against lesions induced by absolute ethanol), antipruritus (against pruritus induced by Dextran T40 and compound 48/80), acute and visceral antinociceptive (test of subplantar and intracolonic capsaicin) and hepatoprotective (against acetaminophen- and Ga1N/LPS-induced models of hepatitis) effects. In anti-inflammatory test, the resin (200 e 400 mg/kg, p.o.) although failed to modify the carrageenan-induced acute rat paw-edema response, it caused signficant inhibitions at a dose of 400mg/kg on the formation of cotton pellet-induced granulomas and on the vascular permeability increase induced by i.p. acetic acid in mice. In addition, the (200 e 400 mg/kg) showed gastroprotective potential against absolute- and acidified ethanol- induced gastric lesions as evidenced from siginificant diminution in lesion scores, restoration of the ethanol-induced depletion of non-protein sulfhydryl content More over, the resin demonstrated an antisecretory effect on gastric acid secretion induced in 4-h pylorus ligated rats. The triterpene mixture also produced similar gastroprotection against ethanol-induced lesions in a manner similar to capsaicin, a pungent principle from hot peppers. This protection possibly involves capsaicin-sencitive primary afferents since it was abolished in mice pretreated with a neurotoxic dose of capsaicin. The α and β â amyrin mixture (100 mg/kg) manifested antipruritus effect as evidenced from suppression of scratching behaviour in the mouse model of prurits induced by s.c. injections of dextran T40 and compound 48/80. Besides, it also produced an antiedematogenic effect in model of hind paw edema induced by histamine, compound 48/80 and dextran T40 and markedly depressed the compound 48/80-elicited rat mast cell degranulation (ex vivo). An antinociceptive effect of triterpenoid mixture (3-100 mg/kg) was observed in capsaicin-evoked somatic (1.6 μg/site, suplantar) and visceral (149 μg, intracolonic) models of nociception in mice. Greater suppression of nociceptive behaviors were evidenced at a dose of 10 mg/kg α and β â amyrin mixture, which mimicked the effect produced by ruthenium red, a non-competitive capsaicin antagonist. The antinociceptive effect of triterpenoid mixture was found to be naloxone (2 mg/kg)- sensitive, suggesting an opioid mechanism. A blockade by triterpene mixture was also evidenced on the hyperthermic but not the hypothermic response of subcutaneously administered capsaicin (10 mg/kg) suggesting possible incolvement of TRPV1 receptor. In open-field and rota-rod tests, the triterpene mixture did not manifest signs of either sedation or motor abnormality in mice that could account for the observed antinociception. In the model of acetaminophen (500 mg/kg)-induced hepatotoxicity, the triterpenoid mixture (50 and 100 mg/kg) effectively reduced the elevated serum AST and ALT levels, restored the depleted GSH and markedly diminished the histopathological alterations. Potentation of pentobarbital-sleeping time was, however observed at these doses of triterpenoid, incidating a probable suppression of cytochrome P450 and thus a diminished metabolite formation that may account for reduced acetaminophen toxicity. The α- and β â amyrin mixture offered complete protection against the mortality associated with Ga1N/LPS , but caused only a moderate diminution of serum enzymes and histopathological alterations. Taken together, these findings show that the resin and α- and β â amyrin mixture possess low toxicity and have a wide therapeutic potential with anti-inflammatory, antinociceptive, antipruritus, and gastro- and hepato-protective actions. Most of the effects of triterpenoid mixture appear to involve in part the participation of primary sensory afferents in their actions. / A espÃcie Protium heptaphyllum (Aubl.) March (Burseraceae) popularmente conhecida como almÃcega, à encontrada na regiÃo AmazÃnica, em vÃrios Estados do Brasil e paÃses da AmÃrica do Sul. Esta espÃcie exsuda uma resina oleosa e amorfa, usada na medicina popular como analgÃsico, cicatrizante e expectorante. Estudos fitoquÃmicos demonstraram a presenÃa de monoterpenos e triterpenos pentacÃclicos, tais como α - amirina e β - amirina, maniladilol e breina. O presente trabalho teve como objetivo investigar os efeitos tÃxicos e farmacolÃgicos da resina e de seus constituintes majoritÃrios, a mistura de triterpenos α e β â amirina. Na avaliaÃÃo dos efeitos tÃxicos observamos a toxicidade aguda destes produtos em camundongos e Artemia sp. Analisando os efeitos sistÃmicos, avaliamos a atividade antiinflamatÃria da resina (edema de pata induzido por carragenina, granuloma induzido por âpelletsâ de algodÃo e permeabilidade vascular induzida por Ãcido acÃtico) e da mistura de α e β â amirina (edema induzido por histamina, serotonina, dextrana T40 e composto 48/80). Examinamos ainda as atividades gastroprotetora e antisecretÃria da resina (lesÃes gÃstricas induzidas pelo etanol absoluto e etanol acidificado e secreÃÃo Ãcida induzida pela ligaÃÃo pilÃrica) e as atividades gastroprotetora (lesÃes gÃstricas induzidas pelo etanol absoluto, com animais dessensibilizados por capsaicina), antipruriginosa (prurido induzido pelo dextrana T40 e composto 448/80 e desgranulaÃÃo de mastÃcitos ex vivo) antinociceptiva (nocicepÃÃo induzida pela administraÃÃo subplantar e intracolÃnica de capsaicina, resposta hipotÃrmica induzida por capsaicina) e hepatoprotetora (lesÃes hepÃticas induzidas por acetaminofeno e Ga1N/LPS) da mistura de α e β â amirinas. NÃo foi possÃvel estabelecer as DL50 da resina (atà 5 g/kg, v.o. e 1 g/kg, i.p.) e da mistura de α e β â amirina (atà 3 g/kg, v.o. e atà 2 g/kg, i.p.) em camundongos. A mistura de α e β â amirina, mas nÃo a resina, mostrou toxicidade para Artemisa sp, sendo as CL50 de 42,54  19,96 e 400  27,85 μg/mL, respectivamente. Nos modelos de permeabilidade vascular induzido por Ãcido acÃtico (camundongo) e granuloma induzido por âpelletâ de algodÃo (ratos), a resina demonstrou efeito antiinflamatÃrio significativo na dose de 400mg/kg, reduzindo a permeabilidade vascular e o peso seco do granuloma. Contudo, a reina nÃo apresentou atividade sobre edema induzido por carragenina (ratos). Adicionalmente, a resina preveniu as lesÃes gÃstricas induzidas por etanol absoluto e etanol acidificado, alÃm de impedir a depleÃÃo dos grupos sulfidrilas produzida pelo etanol absoluto nas doses de 200 e 400 mg/kg. Um efeito antisecretÃrio da resina (200 e 400mg/kg) foi observado no modelo de secreÃÃo Ãcida induzida pela ligaÃÃo pilÃrica em ratos. A mistura de α e β â amirina tambÃm exibiu atividade gastroprotetora inibindo as lesÃes gÃstricas por etanol absoluto, cujo mecanismo parece envolver os neurÃnios sensoriais primÃrios sensÃveis à capsaicina. A administraÃÃo oral dos triterpenos α e β â amirina (100 mg/kg), apresentou atividade antiedematogÃnica, nos modelos de edema de pata induzidos por histamina, composto 48/80 e dextrana T40, mas nÃo sobre o edema induzido por serotonina. A atividade antipruriginosa tambÃm foi observada com as α e β â amirina nas doses variando de 50 a 200 mg/kg, em modelos de prurido induzido por dextrana T40 e pelo composto 48/80 e na reduÃÃo (100 mg/kg) da degranulaÃÃo de mastÃcitos peritoneais ex vivo pelo composto 48/80. O efeito antinociceptivo da mistura, nas doses de 3 a 100 mg/kg, foi verificado atravÃs da inibiÃÃo dos comportamentos de nocicepÃÃo induzidos pela administraÃÃo subplantar ou intracolÃnica de capsaicina em camundongos. A antinocicepÃÃo produzida por estes triterpenos (10 mg/kg) sobre o tempo de lambedura induzido pela capsaicina (1,6 μg/20 μL) nÃo foi potencializada nem revestida pelo vermelho de rutÃnio (1,5 mg/kg), mas foi significativamente inibida pela naloxona (2 mg/kg), sugerindo mecanismo opiÃide. A participaÃÃo dos receptores α2 - adrenÃrgicos neste efeito tambÃm foi eliminada, tendo em vista que a ioimbina nÃo reverteu o efeito antinociceptivo das amirinas no modelo de nocicepÃÃo visceral induzida pela capsaicina. Estes triterpenos bloquearam ainda a hipertermia induzida pela capsaicina (10 mg/kg), mas nÃo reverteram a resposta hipotÃrmica induzida por este agente, sugerindo a participaÃÃo do receptor vanilÃide (TRPV1) no efeito antinociceptivo das amirinas. Nos modelos de hepatoxidade, a mistura de α e β â amirina (50 e 100 mg/kg) reduziu o aumento dos nÃveis sÃricos de ALT e AST e restabeleceu os nÃveis de GSH hepÃticos, diminuindo as alteraÃÃes histopatolÃgicas induzidas pelo acetaminofeno (500 mg/kg), alÃm de potencializar o tempo de sono induzido por pentobarbital sÃdico (50 mg/kg), indicando que este efeito hepatoprotetor envolve a inibiÃÃo do citocromo P â 450. A mistura ofereceu ainda completa proteÃÃo contra a mortalidade induzida por Ga1N/LPS, reduzindo as lesÃes hepÃticas em camundongos e reduzindo os nÃveis sÃricos de ALT, mas nÃo de AST ou GSH hepÃticos, sugerindo um possÃvel feito neuroimunomodulatÃrio neste modelo. Os triterpenos α e β â amirina nas doses variando de 3 a 30 mg/kg, nÃo manifestam efeitos sedativos ou incoordenaÃÃo motora em camundongos. A resina e mistura de α e β â amirina possuem baixa toxicidade e atividades antiinflamatÃria e gastroprotetora. Os triterpenos α e β â amirina exibiram atividade antipruriginosa, antinociceptiva e hepatoprotetora, cujos efeitos envolvem, pelo menos em parte, a participaÃÃo dos neurÃnios aferentes sensoriais primÃrios.
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Estudo fitoquímico e atividade biológica de Aegiphila integrifolia (Jacq.)Simonia Aparecida Lima do Prado 24 April 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A presente dissertação apresenta o estudo fitoquímico e avaliação biológica do extrato etanólico das folhas de Aegiphila integrifolia (Jacq.) pertencente à família Lamiaceae. O estudo fitoquímico realizado com eluato clorofómico do extrato etanólico das folhas levou ao isolamento e identificação de uma mistura de ácidos graxos na forma de seus ésteres metílicos, uma mistura de, β-sitosterol, estigmasterol e lupeol glicosilados, um flavonoide conhecido como Pectolinarigenina. As misturas de ésteres metílicos foram analisadas e determinadas por Cromatografia Gasosa. As determinações estruturais foram realizadas por meio de métodos espectrométricos mono e bidimensionais como IV, RMN de 1H (500 MHz), RMN de 13C (125 MHz), HSQC, HMBC, ESI-EM e comparação com dados da literatura. O estudo biológico do extrato etanólico apresentou um bom resultado quanto à atividade antioxidante pelo método DPPH comparado ao padrão quercetina. A investigação da toxicidade, de acordo com o teste realizado frente à Artemia salina indicou a baixa toxidade (DL 50% superior a 500 μg mL-1) e quando comparado com valores encontrados na Literatura confirma a baixa toxicidade do gênero Aegiphila frente à Artemia salina. Os ensaios da MIC para os fungos filamentosos, bactérias Gram-Positivas e Gram-Negativas e levedura, apresentaram baixa inibição comparadas com os antibióticos Ampicilina, exceto a levedura Cândida albicans. Esta apresentou inibição satisfatória, 96% aproximadamente para a amostra RR05 (do flavonoide) e 92% para amostra R06 (extrato etanólico) comparando aos antibióticos Nistatina e Miconazol (91%). / This dissertation presents the phytochemical study and biological evaluation of the ethanol extract of Aegiphila integrifolia (Jacq.) belonging to the family Lamiaceae. The phytochemical study of clorofómico eluate of ethanol leaf extract led to the isolation and identification of a mixture of fatty acids as their methyl esters, a mixture of, β - sitosterol, stigmasterol and lupeol glycosylated a flavonoid known as Pectolinarigenin. Mixtures of methyl esters were analyzed and determined by gas chromatography. Structural determinations were made by means of spectroscopic methods such as mono-and two-dimensional IR, 1H NMR (500 MHz), 13C NMR (125 MHz), HSQC, HMBC, ESI-MS and comparison with literature data. The biological study of the ethanol extract showed a good result for antioxidant activity by DPPH method compared to standard quercetin. The investigation of the toxicity of the test conducted according front Artemia salina indicated low toxicity (LD 50 % up to 500 mg mL-1) and compared to values found in literature confirming the low toxicity of the genus Artemia salina front Aegiphila. The MIC tests for filamentous fungi, Gram - Positive and Gram-Negative Bacteria and yeast showed low inhibition compared with Ampicillin antibiotics except the yeast Candida albicans. This inhibition was satisfactory, approximately 96% to RR05 sample (the flavonoid) and 92% for sample R06 (ethanol extract) comparing antibiotic Nystatin and Miconazole (91%).
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Etude phytochimique de trois espèces vénézuéliennes appartenant aux familles Burseraceae, Araliaceae, et Lamiaceae et de deux cultivars de la famille Pittosporaceae / Phytochemical study of three venezuelan species from Burseraceae, Araliaceae and Lamiaceae families and two cultivars of Pittosporaceae family / Estudio fitoquimico de tres especies venezolanas pertinecientes a las familias Burseraceae, Araliaceae y Lamiaceae y de dos cultivares de la familia PittosporaceaeRengifo Carrillo, Mayra Graciela 12 December 2017 (has links)
Cette thèse s'inscrit dans le cadre de la thématique du Laboratoire de Pharmacognosie de l'UFR des Sciences de santé, au sein de l'Université de Bourgogne Franche-Comté et du Laboratoire de Produits Naturels de la Faculté de Sciences, au sein de l'Universidad de Los Andes (Venezuela). Elle vise essentiellement l'isolement, purification et identification de molécules d'origine végétale avec activité biologique. Dans ce contexte, l'étude de plantes vénézuéliennes, Bursera inversa (Burseraceae), Lepechinia Bullata (Lamiaceae) et Hydrocotyle multifida (Araliaceae) avec des cultivars Pittosporum tenuifolium 'Variegatum' et Pittosporum tenuifolium 'Gold star' a conduit à l'obtention de treize glycosides naturels, un dérivé de l'acide caféique et diverses hydrocarbures à longue chaîne par les techniques de chromatographie de couche mince préparative, de chromatographie liquide à moyenne pression, chromatographie liquide haute performance, et de chromatographie liquide sous vide. Les structures ont été élucidées principalement par les techniques spectroscopiques de RMN-1 D et -2D, et de spectrométrie de masse. Il s'agit de treize saponines triterpéniques de type oléanane (parmi lesquelles neuf sont des nouveaux composés naturels) ainsi que de l'acide rosmarinique et des alcanes et esters d'acides gras à longue chaîne. / This thesis was carried out in the Laboratory of Pharmacognosy, on the Health Sciences section of Université de Bourgogne Franche-Comté (France) and also in the Laboratory of Natural Products of Sciences Faculty of Universidad de Los Andes (Venezuela). The aim of this thesis was the isolation, purification and identification of bioactive molecules from several plant species. ln this context, the study of Venezuelan species, Bursera inversa (Bùrseraceae), Lepechinia Bullata (Lamiaceae) and Hydrocotyle multifida (Araliaceae), together with the cultivars, Pittosporum tenuifolium 'Variegatum' and Pittosporum tenuifolium 'Gold star' was carried out. The study led to the isolation of thirteen natural glycosides, one caffeic acid derivative and several long chain hydrocarbons by column chromatography, preparative thin layer chromatography, medium pressure liquid chromatography, high performance chromatography and vacuum liquid chromatography. The structures were elucidate mainly by spectroscopie techniques, NMR-1 D and 2D, and mass spectrometry. The compounds were characterized as thirteen oleanane-type saponins (among them nine are new natural compounds), rosmarinic acid and several long chain alkanes and fattv acid esters / Este trabajo se presenta bajo la forma de secciones, donde en primer lugar se expone una breve introducción acerca de los géneros de interés para este estudio, como son Bursera (Burseraceae), Hydrocotyle (Araliaceae), Lepechinia (Lamiaceae) y Pittosporum (Pittosporaceae); así como los motivos que llevaron a la realización de este estudio fitoquímico. Cada género es tratado en un capítulo diferente, que abarca una revisión bibliográfica extensa (considerando los aspectos etnobotánicos, fitoquímicos y farmacológicos) del género, seguida por el procedimiento experimental llevado a cabo en cada especie analizada y por último el análisis de los resultados obtenidos.Los compuestos aislados de cultivares de Pittosporum tenuifolium estudiados: 'Variegatum' y 'Gold Star' se encuentran descritos en el primer capítulo entre los que se encuentran ocho nuevas saponinas triterpénicas tipo-oleanano: PT-PI y PT-P4 de los tallos deP. tenuifolium 'Variegatum', PT-P2 y PT-P3 de las hojas de este mismo cultivar, PT-P7 y PT-P8 de los tallos de P. tenuifolium 'Gold Star' y por último, PT-P5 y PT-P6 aisladas de los tallos de ambos cultivares. Además también se describe el compuesto ya conocido, udosaponinaF (PT-P9), identificado en los tallos de P. tenuifolium 'Variegatum' De las especie Hydrocotyle multifìda se aislaron cinco saponinas triterpénicas, descritas en el segundo capítulo, las cuales tienen al ácido oleanólico como genina. Dos de las cinco saponinas son productos naturales nuevos, HmE-P3 y HmE-P2 minoritario; las otras tres saponinas son compuestos ya conocidos, momordin I (HmE-P1), sandrosaponina X (HmE-P2 mayoritario) y hemslósido Mal (HmE-P4) En el tercer capítulo que abarca al género Bursera, incluye los resultados del estudio fitoquímico de las semillas de Bursera inversa, entre los que se puede mencionar la identificación de 45 compuestos en las semillas de esta planta. El último capítulo contiene la descripción del compuesto mayoritario, aislado de las mias de Lepechinia bullata e identificado como el ácido rosmarínico (LB-TI).
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