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Composition and Applications of Aloe vera Leaf GelHamman, JH 08 1900 (has links)
Many of the health benefits associated with Aloe vera have been attributed to
the polysaccharides contained in the gel of the leaves. These biological activities include promotion of wound healing, antifungal activity, hypoglycemic or antidiabetic effects antiinflammatory,
anticancer, immunomodulatory and gastroprotective properties. While the
known biological activities of A. vera will be briefly discussed, it is the aim of this review to further highlight recently discovered effects and applications of the leaf gel. These effects include the potential of whole leaf or inner fillet gel liquid preparations of A. vera
to enhance the intestinal absorption and bioavailability of co-administered compounds as well as enhancement of skin permeation. In addition, important pharmaceutical applications such as the use of the dried A. vera gel powder as an excipient in sustained release pharmaceutical dosage forms will be outlined.
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Studies on Chemical Transformation and Biological Activities of Ambrein from Sperm Whale Physeter macrocephalus L.Cheng, Shi-Yie 07 July 2005 (has links)
Ambergris, a secretion from the large intestine of the sperm whale, is one of the most important animal perfumes. It is abundant in steroid lipids, the tricyclic triterpene ambrein, a fatty compound bearing some resemblance to cholesterin on considered as one of the main constituents. Ambrein has been used as a stimulant to the circulatory and nervous systems. It has likewise been employed in low grades of fevers and the folk use of this drug as an aphrodisiac is well known. It is more generally used in the preparation of perfumes.
(E)-Ambrein (1) was used as starting material for allylic oxidation with SeO2 / dioxane to yield 15£\-hydroxy-(E)-ambrein (2), 15£]-hydroxy-(E)-ambrein (3), 27-
hydroxy-(E)-ambrein (4) and 15-oxo-(E)-ambrein (5). Compounds 2, 3 and 4 were modified by benzoylation with benzoyl chloride / pyridine to afford 15£\-benzoyl-
(E)-ambrein (6), 15£]-benzoyl-(E)-ambrein (7) and 27-benzoyl-(E)-ambrein (8). On the other hand, compound 3 was modified by cyclization with PPTS to give 8£\,13-
epoxy-(E)-ambrein (9) and 8£\,15-epoxy-(E)-ambrein (10) which were crystallized from CH2Cl2 / MeOH ( 1:10 ). A mixture of compounds 3 and 4 was subjected to oxidation by PCC to produce compound 5. In addition, the absolute configurations of compounds 3 and 4 were determined by Mosher¡¦s method. Moreover, 8£],13-
Epoxy-14-hydroxy-(E)-ambrein (11) and 4-(2,2-dimethyl-6-methylene-cyclohexyl)
-butan-2-one (12) were obtained from photoreaction of 1.
The structures of these modified compounds were determined on the basis of 1D and 2D NMR techniques including 1H-NMR, 13C-NMR, DEPT, COSY, HMQC, HMBC and NOESY experiments and single-crystal X-ray structural analysis. The cytotoxic activities of all the synthetic compounds were determined against Hepa59T / VGH, WiDr, A-549 and MCF-7 cells using the MTT assay. Among the tested compounds, 2 and 5 showed moderate cytotoxic activity against tumor cells. Compound 3 exhibited moderate cytotoxicity against A-549 cells selectively.
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Application of a particle filtration method in the search for new bioactive natural products from fungiYusof, Mohd Termizi Bin January 2008 (has links)
Fungi have been an important source for producing a wide range of secondary metabolites of widely differing chemical structures, as well as biological activities. Many of their metabolites now play a major role in pharmaceutical and agricultural industries. A number of fungi were isolated from soil and leaf litter collected from Arthur’s Pass, West Coast and Kaituna Valley using a particle filtration technique. Fungi were selected based on their unusual morphology or observed cytotoxicity and antimicrobial activity for large scale culture and extraction. A pale yellow compound was isolated from cytotoxic extracts from the culture of Aspergillus versicolor. This compound was identified as sterigmatocystin and the identity confirmed by UV profile and mass spectrometry. Five compounds were isolated from extracts prepared from two different species of Penicillium of which three were active against P388 cells (mycophenolic acid, cycloaspeptide A and mevastatin), one was active against dermatophytes (griseofulvin) and one was not active (3,4,6,8-tetrahydroxy-3-methyl-3,4-dihydroisocoumarin). Two compounds were isolated from extracts prepared from two different species of Phoma. A dark red compound was found to be novel and showed activity against P388 cells and Bacillus subtilis. A second compound also showing cytotoxicity was identified as the known compound phomenone. A further new compound was isolated from extracts of an identified dematiaceous fungus. This alkyl glucoside, however, was not bioactive.
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Application of a particle filtration method in the search for new bioactive natural products from fungiYusof, Mohd Termizi Bin January 2008 (has links)
Fungi have been an important source for producing a wide range of secondary metabolites of widely differing chemical structures, as well as biological activities. Many of their metabolites now play a major role in pharmaceutical and agricultural industries. A number of fungi were isolated from soil and leaf litter collected from Arthur’s Pass, West Coast and Kaituna Valley using a particle filtration technique. Fungi were selected based on their unusual morphology or observed cytotoxicity and antimicrobial activity for large scale culture and extraction. A pale yellow compound was isolated from cytotoxic extracts from the culture of Aspergillus versicolor. This compound was identified as sterigmatocystin and the identity confirmed by UV profile and mass spectrometry. Five compounds were isolated from extracts prepared from two different species of Penicillium of which three were active against P388 cells (mycophenolic acid, cycloaspeptide A and mevastatin), one was active against dermatophytes (griseofulvin) and one was not active (3,4,6,8-tetrahydroxy-3-methyl-3,4-dihydroisocoumarin). Two compounds were isolated from extracts prepared from two different species of Phoma. A dark red compound was found to be novel and showed activity against P388 cells and Bacillus subtilis. A second compound also showing cytotoxicity was identified as the known compound phomenone. A further new compound was isolated from extracts of an identified dematiaceous fungus. This alkyl glucoside, however, was not bioactive.
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Structure-activity relationship studies of biological activities of chemicalsDimayuga, Mario Arnulfo De Leon January 1991 (has links)
No description available.
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Perfil químico e atividades biológicas de Croton echinocarpus Baill. e Croton vulnerarius Müll.Arg / Chemical profile and biological activities of Croton echinocarpus Baill. and Croton vulnerarius Müll.ArgAthayde, Natália Ravanelli 19 November 2013 (has links)
O gênero Croton abriga aproximadamente 1300 espécies, muitas delas reconhecidas pela sua utilização terapêutica, que se deve a presença de grande diversidade de metabólitos secundários. Tais propriedades foram ponto de partida para investigações sobre as propriedades fitoquímicas do gênero. C. vulnerarius e C. echinocarpus são espécies endêmicas do Brasil pertencentes à seção Cyclostigma e até então pouco estudadas. Neste projeto foram extraídos, identificados e isolados componentes químicos destas espécies e analisadas as suas propriedades bioativas (antioxidante, antimicrobiana e anti-HIV). Foi verificado que, diferentemente de outras espécies da mesma seção, C. echinocarpus e C. vulnerarius não apresentam diterpenos em sua composição. No entanto, C. echinocarpus possui entre seus principais componentes um alcaloide, identificado por espectrometria de massas como coridina. Em relação às substâncias fenólicas, observamos que as espécies possuem perfis semelhantes, com alguns flavonoides em comum, sendo que o principal componente de C. echinocarpus é a apigenina vitexina e de C. vulnerarius , o derivado de campferol tilirosídeo. Em relação às atividades biológicas, foi verificado que ambas as espécies possuem potencial antioxidante e antimicrobiano contra espécies de bactérias Gram negativas, especialmente nos extratos mais ricos em compostos fenólicos. Quanto à ação anti-HIV, foi observado que a fração contendo o alcaloide coridina isolado apresentou um grande potencial de atividade anti transcriptase reversa, atingindo valores acima de 90% de atividade, mesmo para a menor concentração testada / Croton comprises approximately 1,300 species, many of them known for their therapeutic uses, which is due to the presence of a large diversity of secondary metabolites. Those properties were the starting point for research on the phytochemical characteristics of the genus. C. vulnerarius e C. echinocarpus are Brazilian endemic species belonging to section Cyclostigma. This project aimed the extraction, identification and isolation of chemical constituents from both species and the analyze of the bioactive properties of such constituents (antioxidant, antimicrobial and anti-HIV). It was found that, unlike other species of the same section, C. echinocarpus and C. vulnerarius does not present diterpenes in their composition. However, C. echinocarpus showed alkaloids among its main constituents, one of them identified by mass spectrometry as coridine. Regarding the phenolic substances, we observed that the two species have similar profiles, with some flavonoids in common. C. echinocarpus presents the flavone C-glycosylated vitexin as its main flavonoid constituent, while C. vulnerarius has the acylated derivative of kaempferol, tiliroside. Regarding the biological activities, both species showed antioxidant potential; antimicrobial effects against Gram-negative bacteria, especially the extracts richer in vitexin; and anti-HIV activity, where the fraction containing the alkaloid coridine showed great potential, reaching values above 90% of the anti-HIV activity, even when the lowest concentration was tested (100 mg.mL-1)
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Atividades biológicas dos alcaloides de Annona crassiflora Mart. / Biological activities of alkaloids of Annona crassiflora Mart.Hidalgo, Edgar Miguel Peña 27 October 2017 (has links)
Annona crassiflora é uma espécie nativa do cerrado brasileiro, conhecida pelo uso popular como alimento e na etnofarmacologia para o tratamento de parasitas do couro cabeludo e de transtornos menstruais. Quimicamente, Annonaceae é conhecida pela produção de acetogeninas e alcaloides benzilisoquinolínicos, dentro dos quais o gênero Annona apresenta a maior diversidade de compostos aporfínicos. O objetivo central deste trabalho foi avaliar potenciais atividades biológicas para Annona crassiflora, relacionadas a sua composição alcaloídica. A análise do extrato foliar de A. crassiflora através de técnicas cromatográficas, espectrométricas e por ressonância magnética nuclear levou a detecção de oito compostos nitrogenados, sendo sete deles identificados: anonaina, annoretina, estefalagina e xilopina, já previamente descritos na espécie, litseglutina B e tetrahidropalmatrubina, identificados pela primeira vez no gênero, e um alcaloide aporfínico inédito proposto como crassiflorina, em homenagem a espécie. A partir das amostras obtidas, foram desenvolvidos diversos ensaios de atividades biológicas, sendo testado o potencial fitotóxico, a atividade antimicrobiana frente as bactérias (Escherichia coli, Pseudomonas aeruginosa e Bacillus subtilis), a inibição de atividade enzimática (acetilcolinesterase e transcriptase-reversa do HIV1) e a atividade antiparasitária (amastigotas e tripomastigotas de Trypanosoma cruzi). Somente dois dos alcaloides identificados, estefalagina e xilopina, foram isolados em quantidades suficientes para alguns bioensaios. De maneira geral, a estefalagina apresentou maior efeito inibitório no alongamento dos coleóptilos de trigo, além de melhores resultados nos ensaios de inibição de atividade enzimática (acetilcolinesterase e HIV1-RT). A xilopina foi mais eficiente nos ensaios fitotóxicos com braquiária (Urochloa decumbens) e com o parasita causador da doença de Chagas (Trypanossoma cruzi). Resultados interessantes com a fração enriquecida em alcaloides também foram obtidos para os ensaios fitotóxicos com espécies-alvo (Lactuca sativa e Lycopersicon esculentum) e antimicrobianos. Estes resultados reforçam o grande potencial biológico dos alcaloides produzidos por Annona crassiflora, sendo, a maioria das atividades descritas neste trabalho, inéditas para estas subtâncias / Annona crassiflora is a native species of Brazilian cerrado, used as food for local people and for treatment of scalp parasites and menstrual disorders in folk medicine. Chemically, Annonaceae is known for the production of acetogenins and benzylisoquinoline alkaloids, within which the Annona genus presents the greatest diversity of aporphine compounds. The aim of this work was to evaluate potential biological activities for Annona crassiflora, related to its alkaloid composition. The analysis of the foliar extract of A. crassiflora by chromatographic, spectrometric and nuclear magnetic resonance techniques led to the detection of eight nitrogen compounds. Seven of which were identified: anonaine, annoretine, stephalagine and xylopine, previously described in the species, litseglutine B and tetrahydropalmatrubine, as first report for the genus, and an unpublished aporphic alkaloid proposed as crassiflorine, in honor of the species. From the obtained samples, several biological assays were developed, being tested the phytotoxic potential, the antimicrobial activity against three bacteria (Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis), the inhibition of enzymatic activity (acetylcholinesterase and transcriptase-reverse of HIV1) and the antiparasitic activity (amastigotes and trypomastigotes of Trypanosoma cruzi). Only two of the identified alkaloids, stephalagine and xylopine, were isolated in sufficient amounts for some bioassays. In general, stephalagine had significant inhibitory effect on wheat coleoptile elongation, as well as strong results in inhibition of enzymatic activity (acetylcholinesterase and HIV1-RT). Xylopine was more efficient in phytotoxic trials with Urochloa decumbens, and with the parasite that causes Chagas disease (Trypanosoma cruzi). Interesting results with an alkaloid enriched fraction were also obtained for the phytotoxic assays with target species (Lactuca sativa and Lycopersicon esculentum) and antimicrobials. These results reinforce the great biological potential of the alkaloids produced by Annona crassiflora. As the best of our knowledge, most of the activities described in this work are unpublished for these compounds
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Fitoquímica e atividades biológicas de plantas do gênero Mikania (Asteraceae). / Phytochemical and biological activities of the Mikania genus plants (Asteraceae).Gregorio, Luiz Elidio 10 October 2008 (has links)
Neste estudo foram obtidos os extratos etanólicos das espécies Mikania parodii Cabrera e Mikania pilosa Baker, os quais foram submetidos a fracionamento utilizando as técnicas de cromatografia líquida a vácuo, em coluna clássica e por exclusão. A partir da espécie Mikania parodii foram isolados e identificados através de comparação dos dados dos espectros de RMN 1H e 13C com a literatura os triterpenos acetato de taraxasterol e acetato de pseudotaraxasterol e os flavonóides caempferol-3-O-glicosídeo e quercetina-3-O-glicosídeo e a partir da espécie Mikania pilosa foi isolado e identificado o flavonóide quercetina 7-metil éter. Os extratos e frações de ambas as plantas foram analisados em técnicas hifenadas (CGEM, CLAE-DAD-EM/EM), permitindo a identificação de 46 substâncias em Mikania parodii e 60 substâncias em M. pilosa compreendendo as seguintes classes: monoterpenos, sesquiterpenos, um diterpeno (M. pilosa), triterpenos, flavonóides, derivados do ácido quínico (ácidos clorogênicos), ácidos graxos e seus ésteres. O extrato etanólico bruto de M. parodii apresentou atividade anticonvulsivante e antialérgica. O extrato etanólico bruto de M. pilosa ressuspendido em água : etanol (7:3) inibiu em mais de 50% e 59% respectivamente as células HCT-8 (carcinoma de cólon) e SF925 glioblastoma humano). A análise dos extratos polares de M. camporum e M. vitifolia em CLAE-DAD-EM/EM em comparação com dados da literatura permitiu a identificação dos derivados do ácido quínico: 5-O-Ecafeoilquínico, 3,5-di-O-E-cafeoilquínico, 4,5-di-O-E-cafeoilquínico e de classes de flavonóides apresentando substituintes metila e hexoses em ambas as espécies. / In this study the ethanolic extracts from the species Mikania parodii Cabrera and Mikania pilosa Baker were obtained and fractionated by vacuum liquid chromatography, column chromatography and size-exclusion chromatography. From the species M. parodii were isolated and identified through the comparison of the 1H and 13C NMR spectral data with those in the literature the triterpenes taraxasterol acetate, pseudotaraxasterol acetate and the flavonoids kaempferol-3-O-glucoside and quercetin-3-O-glucoside. From the species Mikania pilosa was isolated the flavonoid quercetin 7-methyl ether. The extracts and fractions of both plants were analyzed by hyphenated techniques (GC-MS and LC-MS/MS), allowing the identification of 46 compounds in M. parodii and 60 compounds in M. pilosa, comprised the classes: monoterpenes, sesquiterpenes, diterpene (M. pilosa), triterpenes, flavonoids, quinic acid derivatives (chlorogenic acids), fatty acids and esters. The ethanolic crude extract of M. pilosa, ressuspended in water:ethanol (7:3) inhibited more than 50 % and 59% respectively the HCT-8 (colon carcinoma) and SF925 cells (human glioblastome). The analysis of polar extracts of the M. camporum and M. vitifolia species in LC-MS/MS in comparison with literature allow the identification of quinic acid derivatives: 5-O-caffeoylquinic acid; 3,5-di-O-caffeoylquinic acid; 4,5-di-O-caffeoylquinic acid, methyl and O-glucosylflavonoids in both species.
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Alkaloidy Vinca minor (Apocynaceae) a jejich biologická aktivita / Alkaloids of Vinca minor (Apocynaceae) and their biological activitiesKlátilová, Anežka January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical botany Candidate: Anežka Klátilová Supervisor: doc. Ing. Lucie Cahlíková Ph. D. Title of diploma thesis: Alcaloids of Vinca minor (Apocynaceae) and their biological activities The aim of this diploma thesis was to process the assigned fraction isolated from the Vinca minor L. plant and to isolate at least one alkaloid to test its biological activity. Using preparative TLC, the alkaloid was sequentially isolated from the fraction, which was then subjected to a structural analysis. NMR and EI-MS methods were used herein. Thanks to these analyzes, the alkaloid was identified as venoterpine. Furthermore, the alkaloid was prepared to test for biological activity. Thus, the isolated alkaloid was identified as venoterpine and tested for biological activity. The observed inhibitory concentration (IC50) to HuAChE and HuBuChe was more than 500 μM, indicating that venoterpine does not rank as a significant inhibitor of cholinesterase. Likewise, the value of cytotoxic activity, when this activity was found to be greater than 10 μM to colorectal cancer cells as well as to healthy cells, is not significant. Key words: Vinca minor, Apocynaceae, alkaloids, biological activities
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Fitoquímica e atividades biológicas de plantas do gênero Mikania (Asteraceae). / Phytochemical and biological activities of the Mikania genus plants (Asteraceae).Luiz Elidio Gregorio 10 October 2008 (has links)
Neste estudo foram obtidos os extratos etanólicos das espécies Mikania parodii Cabrera e Mikania pilosa Baker, os quais foram submetidos a fracionamento utilizando as técnicas de cromatografia líquida a vácuo, em coluna clássica e por exclusão. A partir da espécie Mikania parodii foram isolados e identificados através de comparação dos dados dos espectros de RMN 1H e 13C com a literatura os triterpenos acetato de taraxasterol e acetato de pseudotaraxasterol e os flavonóides caempferol-3-O-glicosídeo e quercetina-3-O-glicosídeo e a partir da espécie Mikania pilosa foi isolado e identificado o flavonóide quercetina 7-metil éter. Os extratos e frações de ambas as plantas foram analisados em técnicas hifenadas (CGEM, CLAE-DAD-EM/EM), permitindo a identificação de 46 substâncias em Mikania parodii e 60 substâncias em M. pilosa compreendendo as seguintes classes: monoterpenos, sesquiterpenos, um diterpeno (M. pilosa), triterpenos, flavonóides, derivados do ácido quínico (ácidos clorogênicos), ácidos graxos e seus ésteres. O extrato etanólico bruto de M. parodii apresentou atividade anticonvulsivante e antialérgica. O extrato etanólico bruto de M. pilosa ressuspendido em água : etanol (7:3) inibiu em mais de 50% e 59% respectivamente as células HCT-8 (carcinoma de cólon) e SF925 glioblastoma humano). A análise dos extratos polares de M. camporum e M. vitifolia em CLAE-DAD-EM/EM em comparação com dados da literatura permitiu a identificação dos derivados do ácido quínico: 5-O-Ecafeoilquínico, 3,5-di-O-E-cafeoilquínico, 4,5-di-O-E-cafeoilquínico e de classes de flavonóides apresentando substituintes metila e hexoses em ambas as espécies. / In this study the ethanolic extracts from the species Mikania parodii Cabrera and Mikania pilosa Baker were obtained and fractionated by vacuum liquid chromatography, column chromatography and size-exclusion chromatography. From the species M. parodii were isolated and identified through the comparison of the 1H and 13C NMR spectral data with those in the literature the triterpenes taraxasterol acetate, pseudotaraxasterol acetate and the flavonoids kaempferol-3-O-glucoside and quercetin-3-O-glucoside. From the species Mikania pilosa was isolated the flavonoid quercetin 7-methyl ether. The extracts and fractions of both plants were analyzed by hyphenated techniques (GC-MS and LC-MS/MS), allowing the identification of 46 compounds in M. parodii and 60 compounds in M. pilosa, comprised the classes: monoterpenes, sesquiterpenes, diterpene (M. pilosa), triterpenes, flavonoids, quinic acid derivatives (chlorogenic acids), fatty acids and esters. The ethanolic crude extract of M. pilosa, ressuspended in water:ethanol (7:3) inhibited more than 50 % and 59% respectively the HCT-8 (colon carcinoma) and SF925 cells (human glioblastome). The analysis of polar extracts of the M. camporum and M. vitifolia species in LC-MS/MS in comparison with literature allow the identification of quinic acid derivatives: 5-O-caffeoylquinic acid; 3,5-di-O-caffeoylquinic acid; 4,5-di-O-caffeoylquinic acid, methyl and O-glucosylflavonoids in both species.
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