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Phytochemical Investigations of Costa Rican Marcgraviaceae and Development of Insecticide SynergistsCarballo Arce, Ana F. 10 December 2013 (has links)
Substances of natural and synthetic origin were studied using analytical, bioassay guided isolation, metabolomics and medicinal chemistry techniques. In a section focused on the plant family Marcgraviaceae, a validated method for the quantification of six pentacyclic triterpenes (α and β Amyrin lupeol, ursolic acid, betulin and betulinic acid) in the Souroubea spp was developed. Quantification of the triterpenes in the crude extracts was achieved using HPLC-APCI mass selective detection. The calibration curves for the five triterpenes evaluated were highly linear (r2 >0.993) and percentage recovery from spiked samples were greater than 94% for all compounds. The LOD for betulinic acid was 0.01 µg for betulinic acid on column and LOQ was 0.03 µg. The method was successfully applied to 41 crude extracts from leaf and stem of Souroubea spp, from two locations in Costa Rica. The method is suitable for quality control of raw materials used in the manufacture of natural health products. The use of modern metabolomic techniques, UHPLC-QTOF allowed the identification of five putative makers that can potentially be used in distinguishing between the two Souroubea species.
The validated method was used in the quantification of the above triterpenes in a total of thirteen Marcgraviaceae species collected in Costa Rica. It was established that betulinic acid and β- Amyrin could be used as makers for this family of tropical vines. These same thirteen plants extracts were evaluated in antifungal and quorum sensing inhibition bioassays. Marcgravia nervosa was the only species that showed significant activity in both bioassays. Bioassay guided fractionation of the crude ethanolic extract of M. nervosa led to the identification of 2-methoxynaphthoquinone as the bioactive compound responsible for the bioactivity. The crude leaf ethanolic extract from M. nervosa showed a significant inhibition of QS comparable or somewhat better than D. pulchra extracts with the M. nervosa extract showing stronger inhibiting QS with a halo of 21.8mm, more than D. pulcra extracts which generated a halo of 15.9mm. The active quinone has a MIC of 85 µM against Saccharomyces cerevisiaBY4741 (haploid) and 100 µM against Saccharomyces cerevisiae BY4743 (diploid) compared to berberine (positive control) with a MIC 600 µM for both strains. This quinone is not present in any of the other twelve species of Marcgraviaceae available to us.
In work focusing on organic synthesis, a total of 57 semi-synthetic derivatives of dillapiol, safrol and piperonal were prepared and evaluated for their inhibitory activity in a CYP 3A4 bioassay to assess their potential use as pesticide synergists. The synergistic activity of dillapiol has been improved 45 fold; analog 31 has an IC50 = 0.2 µM compared with dillapiol IC50= 9.18 µM. A number of other compounds structurally related to 31 showed similar levels of activity.
A screening of a compound library identified the amino sulfoxide 3 as a potential lead for the design of a selective connexin blocker with potential application in the treatment of spinal cord injuries. The use of X-ray crystallography permitted the correction of the original structure assigned to 3. Once the structure was corrected a total of 6 analogs were prepared. Compound 3 has the highest inhibition of GJIC whereas compound 8 and compound 2, reduced anionic hemi-channel activity. Compound 2 also reduced the cationic activity of the hemi-channels.
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Estudo fitoquímico e atividades biológicas de Gomphrena elegans Mart. (Amaranthaceae) /Mahmoud, Talal Suleiman. January 2010 (has links)
Orientador: José Eduardo de Oliveira / Banca: Márcia Nasser Lopes / Banca: Luís Vitor Silva do Sacramento / Banca: Marcos Roberto Monteiro / Banca: Dionéia Camilo Rodrigues de Oliveira / Resumo: O trabalho descreve a identificação, isolamento, elucidação estrutural de constituintes químicos de Gomphrena elegans, bem como a avaliação do perfil químico e a avaliação das potenciais atividades antineoplásica, alelopática, inseticida e antifúngica dos extratos dessa espécie provenientes de coleta realizada em março de 2007. As extrações das substâncias orgânicas foram feitas por sonicação durante 120 minutos e o sistema de solvente mais favorável foi hexano, clorofórmio, metanol e água. Os estudos fitoquímicos dos extratos das folhas, caule aéreo, caule submerso e raiz adventícia resultaram na identificação de 54 substâncias naturais pertencentes a classes distintas e o sal KNO3. A cromatografia CG-EM dos extratos hexânicos permitiu identificar 37 substâncias sendo: 14 alcanos (pentadecano, hexadecano, heptadecano, octadecano, nonadecano, 3-etil-5-(2- etilbutil)-octadecano, eicosano, docosano, tricosano, tetracosano, pentacosano, hexacosano, heptacosano e nonacosano); 7 alcenos (1-hexadeceno, 1-octadeceno, 3-eicoseno, 8-metil-1-deceno, 9-eicoseno, docoseno e 1-hexacoseno); 8 ésteres (palmitato de metila, palmitato de etila, linoleato de metila, linolenato de metila, 6- octadecenoato de metila, linoleolato de etila, linolenato de etila e 9-octadecenoato de etila); 1 aromático (diisobutil ftalato); 4 terpenos (dihidroactinidiolide, 7,11,15-trimetil- 3-metileno-hexadec-1-eno, laurenan-2-ona e esqualeno); 1 álcool (1-hexadecanol) e 2 cetona (6,10,14-trimetil-2-pentadecanona e 7,9-di-ter-butil-oxaspiro[4.5]deca-6,9- dien-2,8-diona). Os extratos clorofórmicos, metanólico e aquoso possibilitaram o isolamento de 20 substâncias sendo: 3 esteróides (b- sitostenona, b-sitosterol e 5α- estigmasta-7,22-dien-3b-ol); 2 terpenos (jatrofona e esqualeno); 6 ésteres... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work describes the identification, isolation and the structure of Gomphrena elegans chemical components. It also assesses the chemical profile and potential anticancer, allelopathic, insecticidal and antifungal activity of extracts from this species, collected in March 2007. Organic compounds were extracted through sonication during 120 minutes. The most favorable solvent system was: hexane, chloroform, methanol and water. The extracts phytochemical studies (from leaves, aerial stem, submerse stem and adventitious root) identified 54 natural substances from different classes and the KNO3 salt. Gas chromatography copled with mass spectrometry (GC-MS) of hexane extracts identified 37 substances: 14 alkanes (pentadecane, hexadecane, heptadecane, octadecane nonadecane, 3-ethyl-5-(2- ethyl-butyl)-octadecane eicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane and nonacosane); 7 alkenes (1-hexadecene, 1- octadecene, 3-eicosene, 8-methyl-1-decene, 9-eicosene, docosene and 1- hexacosene); 8 esters (methyl palmitate, ethyl palmitate, methyl linoleate, methyl linolenate, 6-octadecenoate methyl, ethyl linoleolate, ethyl linolenate and 9- octadecenoate ethyl); 1 aromatic (diisobutil phthalate); 4 terpenes (dihydroactinidiolide, 7,11,15-trimethyl-3-methylene-hexadeca-1-ene, laurenan-2-one and squalene); 1 alcohol (1-hexadecanol) and 2 ketones (6,10,14-trimethyl-2- pentadecanone and 7,9-di-tert-butyl-oxaspiro[4.5]deca-6,9-dien-2,8-dione). The chloroform, methanol and water extracts allowed the isolation of 20 substances... (Complete abstract click electronic access below) / Doutor
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Bioprospecção em espécies de Fabaceae: agentes quimiopreventivos e substâncias de interesse agrocêutico /Marqui, Sara Regina de. January 2011 (has links)
Orientador: Dulce Helena Siqueira Silva / Banca: Nivaldo Boralle / Banca: João Henrique Ghilardi Lago / Banca: Ana Helena Januário / Banca: Cecília Verônica Nunez / Resumo: A família Fabaceae é composta de 650 gêneros com aproximadamente 18.000 espécies. É uma família economicamente importante, extensivamente estudada e bem distribuída em regiões tropicais e subtropicais. É conhecida como Leguminosae, associada aos frutos típicos destas plantas, que são legumes com favas. Poucas espécies dos gêneros Inga e Swartzia foram investigadas quimicamente, sendo que algumas apresentaram atividades biológicas importantes, associadas principalmente à presença de saponinas em Swartzia e de antioxidantes polifenólicos em Inga, por causa da elevada capacidade sequestradora de radicais livres associadas com várias doenças neurodegenerativas, coronárias (CHD) e câncer. O estudo de Inga laurina e Swartzia langsdorffii evidenciou a sua composição química bem como seu potencial de atividade biológica, destacando-se atividade antioxidante, antifúngica e nematoestática. O extrato etanólico das folhas de Swartzia langsdorffii foi submetido a etapas de fracionamento cromatográfico, incluindo o uso de CLAE para purificação dos constituintes químicos majoritários: os triterpenos pentacíclicos ácido oleanólico (1) e o lupeol (2), ácido 3-soforosiloleanólico (3) e saponina 3-O--D-(6'-metil)-glicopiranosilolean-28-oato de -glucopiranosila (4), inédita. As substâncias 1, 2 e 4 mostraram-se moderadamente ativas quando biautografadas com fungos fitopatogênicos Cladosporium cladosporioides e C. sphaerospermum. As substâncias 3 e 4 mostraram-se moderadamente ativas frentes aos fungos patógenos humanos Candida albicans, C. krusei, C. parapsilosis and Cryptococcus neoformans em ensaios de microdiluição. Análise preliminar do extrato bruto das folhas e ramos das espécies de Inga edulis, I. laurina e I. marginata apresentaram atividade antioxidante em teste com solução de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Fabaceae family comprises 650 genera with ca. 18.000 species widespread in tropical and subtropical regions. This family is large, economically important and extensively studied. It is also known as Leguminosae, referring to the typical fruit of these plants, which are called legumes. Few species of Swartzia and Inga genera have been investigated, although some present important biological properties, especially associated with the presence of triterpenes and saponins in Swartzia and of antioxidant phenolics in Inga species, and their well-known effects on the prevention of oxidative stress-associated diseases as neurodegenerative, coronary heart disease (CHD) and cancer. The phytochemical study on Inga laurina e Swartzia langsdorffii has focused on the search for bioactive compounds, especially antifungal, antioxidant and antiparasitic, from São Paulo flora. The ethanol extract from leaves of Swartzia langsdorffii was submitted to chromatographic procedures, including the use of HPLC, and the hexane fraction afforded pentacyclic triterpenes oleanolic acid (1) and lupeol (2). The ethyl acetate fraction afforded oleanolic acid 3-sophoroside (3) and the methanol/water fraction afforded a new saponin 3-O--D-(6'-methyl)-glucopyranosyl-28-O--D-glucopyranosyl-oleanate (4). Compounds 1, 3 and 4 showed moderate activity when bioautographed with phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum, whereas compounds 3 and 4 showed moderate antifungal activity when bioautographed with human pathogens Candida albicans, C. krusei, C. parapsilosis and Cryptococcus neoformans. Preliminary analysis of Inga edulis, I. laurina e I. marginata leaves crude extract by a TLC test with beta-carotene and by a liposome model using Fe2+ as radicalar reactions initiator, indicated the... (Complete abstract click electronic access below) / Doutor
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Estudo QuÃmico de uma amostra de PrÃpolis Verde de Passa Quatro-MG / Chemical study of a sample of Green Propolis Passa Quatro - Minas GeraisLeonardo Carvalho Tavares 25 February 2010 (has links)
A prÃpolis, produto de apiÃrios comercializado em paralelo ao mel, Ã um material resinoso de consistÃncia viscosa elaborado pelas abelhas que coletam matÃria-prima de diversas partes de plantas como brotos, cascas e exsudatos de Ãrvores. O presente trabalho teve como objetivo a investigaÃÃo fitoquÃmica de uma amostra de prÃpolis de Passa Quatro â MG, onde foram isolados sete constituintes: o Ãcido (E)-3-(4-(3-fenilpronanoiloxi)-3,5-bis(3-metilbut-2-enil) acrÃlico (PRO-1), o Ãcido 3,5-diprenil-4-hidroxicinÃmico (PRO-2), uma mistura de flavonÃis (Ramnocitrina e Eupalitina) (PRO-3) em uma proporÃÃo de 34,5% e 65,5%, respectivamente; os triterpenos lupeol (PRO-4), a mistura de α,β-amirina (PRO-5), um flavonÃide, a acacetina (PRO-6) e o Ãcido 3-prenil-4-hidroxinÃmico (PRO-7). A elucidaÃÃo estrutural das substÃncias isoladas foi realizada atravÃs do uso de tÃcnicas espectromÃtricas como infravermelho (IV), espectrometria de massas (EM e EM-IES) e ressonÃncia magnÃtica nuclear de hidrogÃnio (RMN 1H) e carbono-13 (RMN 13C), incluindo tÃcnicas bidimensionais (COSY, HSQC E HMBC) e comparaÃÃo com dados descritos da literatura. / Propolis, a product marketed in parallel apiaries honey is a viscous resin material prepared by bees that collect raw material from different parts of plants such as buds, bark and tree exudates. The present study aimed to phytochemical investigation of a sample of propolis Passa Quatro - MG, where seven constituents were isolated: the (E)-3-(4-(3-phenylenylpronanoyloxy)-3,5-bis(3-methylbut-2-enyl)acrylic acid (PRO-1), the 3,5-diprenyl-4-hydroxycinnamic acid (PRO-2), a mixture of flavonols (Ramnocitrin and Eupalitin) (PRO-3) in a ratio of 34 5% and 65.5 % respectively; the triterpene lupeol (PRO-4), the mixture of α,β-amyrin (PRO-5), a flavonoid, a acacetin (PRO-6) and the 3-prenyl-4-hydroxycinnamic (PRO-7) . The structural elucidation of the isolated compounds was performed by using spectroscopic techniques such as infrared (IR), mass spectrometry (MS and ESI-MS) and nuclear magnetic resonance of hydrogen (1H NMR) and carbon-13 (13C-NMR), techniques including two dimensional (COSY, HSQC and HMBC) and comparison with the data described in the literature.
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Policetídeos e lignóides do tegumento de virola elongata warb. (Myristicaceae) / Poliketides and lignoids of the Tegument from Virola elongata (Spr. ex Benth) Warb.Massuo Jorge Kato 16 March 1984 (has links)
A presente dissertação descreve o isolamento e elucidação estrutural de alguns constituíntes químicos do tegumento de V. elongata, espécie envolvida em usos etnofarmacológicos. 0 extrato clorofórmico forneceu além de ésteres alifáticos e triglicerídeos dois policetídeos do tipo diarilalcanoílicos: 1-(2\',6\'- Dihidroxi-4\'-metoxifeni1)-12-fenil-dodecan-1-ona (inédito) e 1-(2\',4\',6\'- Trihidroxi-3\',4\'-dihidrofeni1)-11-fenil-undecan-1-ona (conhecido) ; três lignanas furofufurânicas: (1R,2S,5R,6R)-6-(3\',4\'-Dimetoxifeni1)-2-(3\",4\"-metilenodioxifeni1)-3,7-dioxabiciclo‌3.3.0‌ octano (fargesina); (1R,2S,5R,6R)-2,6-Bis-(3\",4\" -dimetoxifeni1)-3,7-dioxabiciclo- ‌3.3.0‌ octano (epieudesmina) e (1R,2S,5R,6S)-2,6-Bis-(3\",4\" -dimetoxifenil)-3,7-dioxabiciclo ‌3.3.0‌ octano (eudesmina); e duas neolignanas tetraidrofurânicas: (1S,2S,5R,6R)-1-Metil - 2-(3\",4\"-metilenodioxifeni1)-5-(α-hidroxi-3\" 1,4\'\"-dimetoxibenzil)-tetraidrofurano (inédita) e (15,2S,5R,6R)-1-Metil-2-(3\",4\"-dimetoxifeni1)-5-(α-hidroxi-3\'\",4\'\"-dimetoxibenzil)-tetraidrofurano (magnostelina A). 0 isolamento dos constituíntes químicos foi baseada em técnicas cromatográficas e a elucidação estrutural em métodos espectrométricos usuais (UV, IV, DRO, RMN de 1H e de 13C). A comprovação da estrutura do policetídeo Ve-6 foi baseada na aromatização por desidratação em meio ácido. A determinação da configuração relativa das neolignanas tetreidrofurânicas foi baseada em estudo envolvendo o reagente de deslocamento Eu(fod)3. A determinação da configuração absoluta foi baseada na conversão em uma neolignana tetralínica e comparação de sua curva de DRO com compostos modêlos. / The present dissertation describe isolation and structural elucidation of some chemicals constituents of tegument from V. elongata, involved in ethnopharmacology uses. The chloroform extract afford besides aliphatics esthers and triglycerides, two poliketides of the diarylalkanoyl type: 1-(2\',6\'-Dihydroxypheny1)-12-dodecan-l-one and 1-(2\',4\',6\'-Trihydroxy-3\',5\'-dihydropheny1)-11-phenyl-undecan-1-one, the former is unknown and the latter is known; three furofuranic lignans type: (1R, 2S, 5R, 6R) -6- (3\',4\'-Dimethoxypheny1)-2-(3\",4\" -methylenedioxypheny1)-3,7-dioxabicycle‌3.3.0‌ octane (fargesin); (1R,2S,5R,6R)-2,6-Bis-(3\",4\"-dimethoxypheny1)-3,7-dioxabicycle‌3.3.0‌octane (epieudesmin) and (1R,2S,5R,6S)-2,6-Bis-(3\",4\" -dimethoxypheny1)-3,7-dioxabicycle‌3.3.0‌ octane (eudesmin); and two neolignans of the tetrahydrofuranic type:(1S,2S,5R,6R)-1-Methy1-2-(3\",4\" -methylenedioxypheny1)-5-(α-hydroxy-3\'\",4\'\" -dimethoxybenzy1)-tetrahydrofuran (unknow) and (1S,2S,5R,6R)-1-Methy1-2-(3\",4\" -dimethoxypheni1)-5-(α-hydroxy-3\'\",4\'\"-dimethoxybenzy1)-tetrahydrofuran (magnostelin A). Isolation of chemical constituents was based on chromatographic techniques and structural determination on usual spectrometric methods (UV, IR, MS, ORD, 1H and 13C NMR). Poliketyde skeleton was elucidated by acid catalized dehydration yielding a diarylic compound. The relative structure of tetrahydrofuranic neolignans was based in lanthanide induced shift reagent. The absolute configuration was based on chemical transformation to tetralinic neolignan and comparison of its ORD curve with model compounds curves.
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Estudo fitoquímico e ensaios biológicos de Davilla Kunthii A. St. Hil (Dilleniaceae)Leandro da Silva Nascimento 03 April 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O uso de plantas ou extratos de plantas para propósitos medicinais tem sido realizado a milhares de anos. O estudo químico e biológico de plantas constitui numa estratégia alternativa na procura de novos agentes terapêuticos para a identificação de compostos bioativos. A espécie Davilla kunthii A. St. Hil, pertencente à família Dilleniaceae, é conhecida popularmente como cipódefogo e podem ser encontradas em regiões de savana. Este trabalho teve como objetivo realizar o estudo fitoquímico e ensaios biológicos da espécie Davilla kunthii A. St. Hil, tendo em vista que até o presente não foram encontrados registros químicos e biológicos a respeito desta espécie.
A espécie foi coletada no Campus Cauamé do Centro de Ciências Agrárias da Universidade Federal de Roraima (CCA/UFRR). Para a preparação dos extratos hexanico e etanólico das folhas de D. kunthii A. St. Hil os materiais vegetais foram acondicionados em mariotes de vidro para extração a frio em n-hexano e, depois, etanol. O extrato etanólico das folhas, que após particionados, renderam as frações em hexano, clorofórmio, acetato de etila e metanol. As frações do extrato clorofórmico foram purificadas e analisadas através de métodos cromatográficos. Os compostos foram identificados através de técnicas espectroscópicas e comparados com dados da literatura.
O estudo fitoquímico das folhas levou ao isolamento e identificação de uma mistura de ácidos graxos na forma de seus ésteres metílicos (determinados por CG), uma mistura de β-Sitosterol e Estigmasterol e do álcool Triacontan-1-ol (Álcool Melíssilico). Nos ensaios biológicos o extrato das folhas apresentaram uma variação MIC (Mínima Concentração Inibitória) de 6,2 a 53,7% para as bactérias S. aureus e S. sanguinis. Já para as bactérias E. coli e S. tiphymurium o MIC variou de 9,23 a 38,2% e para a levedura C. albicans o MIC foi de 92,5 a 95,3%. Conclui-se que o extrato etanólico das folhas de D. kunthii A. St. Hil apresentou uma baixa toxicidade frente à Artemia salina, uma excelente atividade contra a levedura C. albicans além de revelar uma grande capacidade antioxidante da espécie pelo método de redução do radical DPPH. No entanto, como ainda não foram encontrado relato sobre a referida espécie espera-se que estes resultados possam contribuir para o estudo fitoquímico desta planta. / The use of plants or plant extracts for medicinal purposes has been done for thousands of years. The chemical and biological study of plants is an alternative strategy in the search for new therapeutic agents for the identification of bioactive compounds. The Davilla kunthii A. St.-Hil species belonging to Dilleniaceae family, is popularly known as vine-of-fire and can be found in savanna regions. This work aimed to make the phytochemical study and biological assays of the species Davilla kunthii A. St.-Hil, considering that to date regarding chemical and biological records of this species were not found.
The species was collected in the Campus Center Cauamé Agricultural Sciences, Federal University of Roraima (CCA / UFRR). For the preparation of hexane and ethanol extracts of the leaves of D. kunthii A. St.-Hil plant materials were placed in glass mariotes for cold extraction in n-hexane and then ethanol. The ethanol extract of the leaves, which after partitioned, yielded fractions in hexane, chloroform, ethyl acetate and methanol. The fractions of the chloroform extract were purified and analyzed by chromatographic methods. The compounds were identified by spectroscopic techniques and compared with literature data. The phytochemical study of leaves led to the isolation and identification of a mixture of fatty acids as their methyl esters (determined by GC), a mixture of β-sitosterol and stigmasterol and alcohol Triacontan-1-ol (Alcohol Melíssilico). In biological assays leaves extract showed a MIC (Minimum Inhibitory Concentration) variation from 6.2 to 53.7% for S. aureus and S. sanguinis bacteria. As for the E. coli bacteria and S. tiphymurium the MIC ranged from 9.23 to 38.2% and the yeast C. albicans MIC was 92.5 to 95.3%. It is concluded that the ethanol extract of the leaves of D. kunthii A. St.-Hil showed low toxicity on Artemia salina, an excellent activity against the yeast C. albicans as well as revealing a great antioxidant capacity of the species by the method of reduction the DPPH radical. However, they were not reported on the species is expected that these results will contribute to the phytochemical study of this plant family.
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Phytochemical Investigations of Costa Rican Marcgraviaceae and Development of Insecticide SynergistsCarballo Arce, Ana F. January 2013 (has links)
Substances of natural and synthetic origin were studied using analytical, bioassay guided isolation, metabolomics and medicinal chemistry techniques. In a section focused on the plant family Marcgraviaceae, a validated method for the quantification of six pentacyclic triterpenes (α and β Amyrin lupeol, ursolic acid, betulin and betulinic acid) in the Souroubea spp was developed. Quantification of the triterpenes in the crude extracts was achieved using HPLC-APCI mass selective detection. The calibration curves for the five triterpenes evaluated were highly linear (r2 >0.993) and percentage recovery from spiked samples were greater than 94% for all compounds. The LOD for betulinic acid was 0.01 µg for betulinic acid on column and LOQ was 0.03 µg. The method was successfully applied to 41 crude extracts from leaf and stem of Souroubea spp, from two locations in Costa Rica. The method is suitable for quality control of raw materials used in the manufacture of natural health products. The use of modern metabolomic techniques, UHPLC-QTOF allowed the identification of five putative makers that can potentially be used in distinguishing between the two Souroubea species.
The validated method was used in the quantification of the above triterpenes in a total of thirteen Marcgraviaceae species collected in Costa Rica. It was established that betulinic acid and β- Amyrin could be used as makers for this family of tropical vines. These same thirteen plants extracts were evaluated in antifungal and quorum sensing inhibition bioassays. Marcgravia nervosa was the only species that showed significant activity in both bioassays. Bioassay guided fractionation of the crude ethanolic extract of M. nervosa led to the identification of 2-methoxynaphthoquinone as the bioactive compound responsible for the bioactivity. The crude leaf ethanolic extract from M. nervosa showed a significant inhibition of QS comparable or somewhat better than D. pulchra extracts with the M. nervosa extract showing stronger inhibiting QS with a halo of 21.8mm, more than D. pulcra extracts which generated a halo of 15.9mm. The active quinone has a MIC of 85 µM against Saccharomyces cerevisiaBY4741 (haploid) and 100 µM against Saccharomyces cerevisiae BY4743 (diploid) compared to berberine (positive control) with a MIC 600 µM for both strains. This quinone is not present in any of the other twelve species of Marcgraviaceae available to us.
In work focusing on organic synthesis, a total of 57 semi-synthetic derivatives of dillapiol, safrol and piperonal were prepared and evaluated for their inhibitory activity in a CYP 3A4 bioassay to assess their potential use as pesticide synergists. The synergistic activity of dillapiol has been improved 45 fold; analog 31 has an IC50 = 0.2 µM compared with dillapiol IC50= 9.18 µM. A number of other compounds structurally related to 31 showed similar levels of activity.
A screening of a compound library identified the amino sulfoxide 3 as a potential lead for the design of a selective connexin blocker with potential application in the treatment of spinal cord injuries. The use of X-ray crystallography permitted the correction of the original structure assigned to 3. Once the structure was corrected a total of 6 analogs were prepared. Compound 3 has the highest inhibition of GJIC whereas compound 8 and compound 2, reduced anionic hemi-channel activity. Compound 2 also reduced the cationic activity of the hemi-channels.
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Relações na tribo Bocageeae Endlicher baseadas em fitoquímica e sequências de DNA / Relationships in tribe Bocageeae Endlicher based on phytochemistry and DNA sequencesCintia Rocini 23 March 2009 (has links)
Existem vários sistemas de classificação para Annonaceae. No entanto, estudos recentes sugerem que esse grande número de classificações pode ser reduzido a um. O sistema elaborado por Fries (1959), por exemplo, apresenta vários grupos apoiados por revisões modernas. Um deles é o Grupo Trigynaea, sinonimizado como tribo Bocageeae Endlicher (Johnson e Murray, 1995). A análise cladística com dados morfológicos sugeriu uma hipótese sobre as relações intergenéricas na tribo (Johnson e Murray, 1995). A confiabilidade dessas relações foi verificada com o uso de dados fitoquímicos e sequências de DNA. Em ((Bocagea, Hornschuchia) (Trigynaea)), o clado (Bocagea, Hornschuchia, Trigynaea) foi detectado na análise Bayesiana do RPB2 e apoiado pela presença de apigenia (exceto em Bocagea) e síntese de quercetina via dihidrocampferol. No clado (((Cardiopetalum, Cymbopetalum) (Porcelia)) (Froesiodendron)) a relação (Cardiopetalum, Cymbopetalum, Porcelia) foi detectado nas análises de Máxima Parcimônia das regiões coxI, RPB2 e trnK-matK e nas análises Bayesianas das regiões coxI, trnL-trnL-F e trnK-matK. Esse clado foi apoiado pela presença de luteolina (exceto em Cardiopetalum e Porcelia) e síntese de quercetina pelas vias di-hidrocampferol e eriodictiol (exceto em Cymbopetalum que produziu luteolina). A presença, até o momento exclusiva em Annonaceae, de alcaloides pirrolizidínicos em Bocageeae e Annona foi congruente com as informações sobre a estreita relação desses grupos. A distribuição dos componentes das ceras delimitou grupos químicos em Bocageeae que não foram congruentes com as relações estabelecidas com os dados morfológicos. / There are several classification systems for Annonaceae. However, recent studies have suggested this high number of classifications can be reduced to one. The system of Fries (1959), for example, presents many groups supported by modern revisions. One of them is Trigynaea-Gruppe, synonym of tribe Bocageeae Endlicher (Johnson and Murray, 1995). The morphological cladistic analysis suggested one hypothesis of intergeneric relationships among the Bocageeae (Johnson and Murray, 1995). The consistency of these relationships was evaluated by the use of phytochemical data and DNA sequences. Within ((Bocagea, Hornschuchia) (Trigynaea)), the (Bocagea, Hornschuchia, Trigynaea) was detected in the Bayesian analysis of RPB2 and supported by presence of apigenin (except in Bocagea) and synthesis of quercetin via dihydrokaempferol. In the clade (((Cardiopetalum, Cymbopetalum) (Porcelia)) (Froesiodendron)), the relationship (Cardiopetalum, Cymbopetalum, Porcelia) was detected in the Maximum Parsimony analyses of coxI, RPB2 and trnK-matK regions, and Bayesian analyses of coxI, trnL-trnL-F e trnK-matK regions. This clade was supported by occurrence of luteolin (except in Cardiopetalum and Porcelia) and synthesis of quercetin via both dihydrokaempferol and eriodictyol (except in Cymbopetalum that produced luteolin). The presence of pyrrolizidine alkaloids in Bocageeae and Annona, unique in Annonaceae until now, was in agreement with information about the closest relationship of these two groups. The distribution of cuticular waxes components circumscribed chemical groups in Bocageeae that were not congruent with the relationships based in morphological data
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Investigating the Phytochemical Profiles of Wild and Cultivated Blueberries (Vaccinium spp.) in Central FloridaKhalid, Anisa 01 January 2022 (has links)
Blueberries (Vaccinium spp.) are valued for their high nutritional quality and flavor. There are five species in the Vaccinium genus native to the state of Florida, but only three are palatable to humans: V. myrsinites, V. darrowii, and V. corymbosum. While V. darrowii has been studied extensively due to its successful hybridization with northern highbush blueberry cultivars, V. myrsinites and wild V. corymbosum have been understudied. This study aims to 1) quantify the abundance of various phytochemicals in fruits of these wild blueberry species and compare fruit quality both among the wild taxa and two varieties of cultivated blueberries (V. corymbosum) and 2) compare the variation of fruit traits across sampling sites. Wild berries were collected from seven different sites across Central Florida, and cultivated berries were collected from a local blueberry farm. Chemical analyses scored for titratable acidity, sugar content, phenolic content, and anthocyanin content. Additionally, measurements were taken for fruit size and water content. Results indicated that V. myrsinites has the highest sugar content and a significantly higher sugar:acid ratio than all other sample types. V. corymbosum and V. myrsinites had similarly high total phenolic concentrations. V. corymbosum had the highest anthocyanin concentration. This exploratory analysis provides new insight into the phytochemical profiles of understudied native Florida blueberries with applications to blueberry breeding efforts.
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Phytochemical studies of Helichrysum patulum.Swartz, Vuyiswa Gladys January 2006 (has links)
<p>Since Helichrysum is known by the indigenous people of Africa for therapeutic properties, such as against colds, flu and wounds, the aim of this study was to focus on the patulum species found predominantly in the Western Cape region of South Africa and by means of isolation and identification of the plant constituents, be able to relate the therapeutic activity on the basis of literature precedents, to the compounds extracted.</p>
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