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1.
Nat Prod Res ; 31(22): 2647-2653, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28278633

RESUMO

The use of kaurane diterpenes as substrates in fungal biotransformation to achieve bioactive compounds has been widely reported. In this work, the natural product kaurenoic acid, a diterpene widely distributed in the plant Kingdom, was chemically converted into ent-15α-hydroxy-kaur-16-en-19-oic acid (1). Substrate 1 was subjected to biotransformation by the fungus Fusarium proliferatum, furnishing a new derivative, ent-2α,15α-dihydroxy-kaur-16-en-19-oic acid (2). The structure of metabolite 2 was deduced on the basis of spectroscopy and MS data. Derivative 2 showed allelopathic activity on germination and growth of root and stem of lettuce (Lactuca sativa), inhibiting 100% of germination and growth of roots and stem, at higher concentration assayed (10-4 mol/L).


Assuntos
Alelopatia , Diterpenos/metabolismo , Diterpenos/farmacologia , Fusarium/metabolismo , Biotransformação , Diterpenos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Lactuca/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Raízes de Plantas/crescimento & desenvolvimento
2.
Nat Prod Res ; 31(16): 1948-1953, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27966397

RESUMO

Luehea species are found in almost all Central and South American countries. The present work describes the phytochemical study, isolation, and structural characterisation of friedelin, ß-friedelinol, lupeol, pseudotaraxasterol, ß-sitosterol, betulinic acid, taraxasterol, (-)-epicatechin, ß-sitosterol-3-O-ß-d-glucopyranoside, and (+)-epicatechin-(4ß→8)-epicatechin from stem barks of Luehea ochrophylla Mart. The structural identification of the isolated compounds was mainly performed by NMR analyses and comparison with the data from literature. These compounds were isolated for the first time in the genus Luehea, except ß-sitosterol glucopyranoside, (-)-epicatechin, and lupeol. Hexane extract (HE) and dichloromethane (DF) and ethyl acetate (AF) fractions exhibited antiparasitic activity against amastigote (intracellular) and trypomastigote culture forms of Trypanosoma cruzi. The ethanol extract (EE), DF, and ethanol fraction (EF) exhibited considerable antifungal activity against Candida albicans. Moreover, extracts and fractions exhibited significant percentage of capture free radicals of 2,2-diphenyl-picrylhydrazyl (DPPH) when compared to the standard of ascorbic acid.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Antiparasitários/farmacologia , Malvaceae/química , Animais , Anti-Infecciosos/química , Antioxidantes/química , Antiparasitários/química , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos/métodos , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/farmacologia , Casca de Planta/química , Extratos Vegetais/química , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Esteróis/isolamento & purificação , Esteróis/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Células Vero , Ácido Betulínico
3.
Nat Prod Res ; 30(21): 2421-8, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27295283

RESUMO

Jacaranda oxyphylla Cham. is popularly known as 'caroba-de-São-Paulo' and it is used in traditional medicine for microbial infections. A new phytoquinoid (α/ß-glucoside-4-phenylacetate-6-(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) (1) was isolated from J. oxyphylla leaves, together with three known compounds: quercetin-3-O-ß-d-galactoside (2), verbascoside (3) and polystyrene (4). Their chemical structures were elucidated using spectroscopic techniques and by comparison with the related known compounds. In addition, it was found a pronounced acetylcholinesterase inhibitory activity for the quinoid 1 (100.0 ± 0.8%) and phenolic compounds 2 and 3 (99.9 ± 0.7 and 99.3 ± 0.5%, respectively), if compared to the standard eserine (92.7 ± 0.4%), that was analysed by a microplate spectrophotometer.


Assuntos
Benzoquinonas/isolamento & purificação , Bignoniaceae/química , Glucosídeos/isolamento & purificação , Anti-Infecciosos/farmacologia , Benzoquinonas/química , Benzoquinonas/farmacologia , Inibidores da Colinesterase/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Folhas de Planta/química
4.
Nat Prod Res ; 30(17): 1974-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26469996

RESUMO

Jacaranda oxyphylla Cham. (Bignoniaceae) is a shrub found in the Brazilian cerrado and used in folk medicine to treat microbial infections. The aim of this study was to carry out a phytochemical screening and evaluate antioedematogenic, antimicrobial and antiacetylcholinesterase properties of J. oxyphylla crude extracts. All extracts analysed showed presence of terpenoids, which are potentially active chemical substances. A high AChE inhibitory activity for hexane extract from leaves and for the extracts from twigs was found. Ethanol extract from leaves of J. oxyphylla showed activity against Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli) bacteria. This extract was also effective in inhibiting the stages of inflammation evaluated. Biological investigation and phytochemical screening of J. oxyphylla extracts provided additional evidence of its traditional medicinal value.


Assuntos
Antibacterianos/farmacologia , Bignoniaceae/química , Inibidores da Colinesterase/farmacologia , Edema/tratamento farmacológico , Antibacterianos/isolamento & purificação , Bacillus cereus/efeitos dos fármacos , Brasil , Inibidores da Colinesterase/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Inflamação/tratamento farmacológico , Medicina Tradicional , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos , Terpenos/isolamento & purificação , Terpenos/farmacologia
5.
ScientificWorldJournal ; 2014: 476207, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715814

RESUMO

Yarrowia lipolytica is a nonpathogenic dimorphic aerobic yeast that stands out due to its ability to grow in hydrophobic environments. This property allowed this yeast to develop an ability to metabolize triglycerides and fatty acids as carbon sources. This feature enables using this species in the bioremediation of environments contaminated with oil spill. In addition, Y. lipolytica has been calling the interest of researchers due to its huge biotechnological potential, associated with the production of several types of metabolites, such as bio-surfactants, γ-decalactone, citric acid, and intracellular lipids and lipase. The production of a metabolite rather than another is influenced by the growing conditions to which Y. lipolytica is subjected. The choice of carbon and nitrogen sources to be used, as well as their concentrations in the growth medium, and the careful determination of fermentation parameters, pH, temperature, and agitation (oxygenation), are essential for efficient metabolites production. This review discusses the biotechnological potential of Y. lipolytica and the best growing conditions for production of some metabolites of biotechnological interest.


Assuntos
Biotecnologia , Yarrowia/fisiologia , Yarrowia/crescimento & desenvolvimento , Yarrowia/metabolismo
6.
Rev. bras. plantas med ; Rev. bras. plantas med;15(2): 293-308, 2013. tab
Artigo em Inglês | LILACS | ID: lil-677040

RESUMO

The Caryocaraceae family is constituted of 25 species distributed in two genera (Caryocar and Anthodiscus). Plants of this family have been used in several phytochemical studies for isolation and characterization of chemical compounds. Some of these studies evaluated in vitro and in vivo biological activities of extracts and pure substances isolated from plants of this family. Nine species of Anthodiscus genus have been described, while no phytochemical study related to them has been reported. On the other hand, Caryocar genus presents 16 species with several medicinal uses like for the treatment of colds and bronchitis, in the prevention of tumours, as a regulating agent of the menstrual flow, to treat ophthalmological problems and for the cure of hematomas and bruises. Some species of this genus were targeted by phytochemical studies and presented, in their composition, the following classes of secondary metabolites: triterpenes, fatty acids, tannins, carotenoids, triterpenic saponins, phenolic coumarins, phenolic glycosides, and others. The fruits of Caryocar species are very nutritive, containing in their composition fibers, proteins, carbohydrates and minerals. Seeds have been widely used as oil source with nutritional and cosmetic value. The biological evaluation of some species was carried out by using relevant biological assays such as: antioxidant, allelopathic and antifungal activities against Biomphalaria glabrata and toxicity on Artemia salina.


A família Caryocaraceae é constituída por 25 espécies distribuídas em dois gêneros (Caryocar e Anthodiscus). Plantas desta família têm sido utilizadas em diversos estudos fitoquímicos para isolamento e caracterização de constituintes químicos. Alguns destes estudos avaliaram atividades biológicas in vitro e in vivo de extratos e substâncias puras isoladas a partir de plantas desta família. São descritas nove espécies dentro do gênero Anthodiscus e nenhum estudo fitoquímico relacionado a elas foi relatado. Por outro lado, o gênero Caryocar apresenta 16 espécies com diversos usos medicinais, tais como: para o tratamento de resfriados, bronquites, na prevenção de tumores, como reguladores do fluxo menstrual, em problemas oftalmológicos, e na cura de hematomas e contusões. Algumas espécies deste gênero foram submetidas a estudos fitoquímicos e apresentaram, em sua composição, as seguintes classes de metabólitos secundários: triterpenos, ácidos graxos, taninos, carotenoides, saponinas triterpênicas, cumarinas, glicosídeos fenólicos, entre outros. Os frutos de espécies Caryocar são muito nutritivos contendo em sua composição, fibras, proteínas, carboidratos e minerais. As sementes têm sido amplamente usadas como fonte de óleo com valor nutricional e cosmético. A avaliação biológica de algumas espécies foi realizada utilizando-se testes biológicos relevantes, entre eles: a atividade antioxidante, alelopática, antifúngica, contra Biomphalaria glabrata, e toxicidade sobre Artemia salina.


Assuntos
Ericales/metabolismo , Plantas Medicinais/classificação , Produtos Biológicos/análise , Compostos Fitoquímicos/análise
7.
Food Sci Technol Int ; 16(4): 315-20, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21339148

RESUMO

The use of fungal and yeast biomass in foodstuff, either as supplements or as major ingredients in formulations is an area of growing interest for the modern food industry. The aim of this study was to evaluate the nutritional potential of biomasses obtained from filamentous fungi Penicillium sclerotiorum, Penicillium janthinellum, Rhizopus stolonifer and Syncephalastrum racemosum. Biomasses presented 26-37% of total proteins, 1.7-3.5% of lipids and 4.6-9.1% of ashes. The humidity level reached 75-83%. Ashes were screened for minerals contents with a special outcome for S. racemosum biomass that presented 3438 mg/100 g (dw) of magnesium. Fatty acids present in the biomasses were screened and the palmitic (C16:0), estearic (C18:0), elaidic (18:1n9-t), oleic (18:1n9-c), linolelaidic (C18:2n6-t), linoleic (C18:2n6-c) and γ-linolenic (C18:3n6) acids were found to be the most abundant, from a total of 88-90% of identified fatty acids. Overall data indicate that the filamentous fungi studied have good nutritional properties, possessing a combination of good level of proteins, low level of fat, and presence of essential fatty acids, including omega-3 derivatives, along with the presence of Ca, Mg, Zn and Fe.


Assuntos
Proteínas Fúngicas/química , Fungos/química , Lipídeos/química , Minerais/química , Cromatografia , Suplementos Nutricionais , Proteínas Fúngicas/metabolismo , Fungos/metabolismo , Clima Tropical
8.
Braz. j. microbiol ; Braz. j. microbiol;40(2): 367-372, Apr.-June 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-520225

RESUMO

A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae) and enzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger atpH 7 (20.8% yield).


Um estudo comparativo do potencial de alguns agentes biológicos capazes de hidrolisar o esteviosídeo foi realizado,objetivando-se estabelecer uma metodologia alternativa para a obtenção da aglicona esteviol ou seu produto de rearranjo, isoesteviol, em rendimentos elevados que permitam o uso destas agliconas para o preparo de novos compostos bioativos. As reações de hidrólise foram realizadas usando fungosfilamentosos (Aspergillus niger, Rhizopus stolonifer e Rhizopus arrhizus), uma levedura (Saccharomyces cerevisiae) e enzimas(pancreatina, lipase PL250 e lipase VFL 8000). A pancreatina mostrou a melhor atividade hidrolítica dentre os sistemastestados, fornecendo isoesteviol com rendimento de 93,9% em pH 4,0, usando tolueno como co-solvente. Esteviol foi produzido tanto usando pancreatina em pH 7,0 (20,2% derendimento) quanto usando A. niger em pH 7,0 (20,8% de rendimento).


Assuntos
Reações Biológicas , Fungos/enzimologia , Fungos/isolamento & purificação , Lipase/análise , Pancreatina/análise , Stevia/enzimologia , Cromatografia Líquida de Alta Pressão , Hidrólise , Métodos , Métodos
9.
Braz J Microbiol ; 40(2): 367-72, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031374

RESUMO

A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae) and enzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger at pH 7 (20.8% yield).

10.
Artigo em Inglês | VETINDEX | ID: vti-444395

RESUMO

A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae)andenzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger at pH 7 (20.8% yield).


Um estudo comparativo do potencial de alguns agentes biológicos capazes de hidrolisar o esteviosídeo foi realizado, objetivando-se estabelecer uma metodologia alternativa para a obtenção da aglicona esteviol ou seu produto de rearranjo, isoesteviol, em rendimentos elevados que permitam o uso destas agliconas para o preparo de novos compostos bioativos. As reações de hidrólise foram realizadas usando fungos filamentosos (Aspergillus niger, Rhizopus stolonifer e Rhizopus arrhizus), uma levedura (Saccharomyces cerevisiae)e enzimas(pancreatina, lipase PL250 e lipase VFL 8000). A pancreatina mostrou a melhor atividade hidrolítica dentre os sistemas testados, fornecendo isoesteviol com rendimento de 93,9% em pH 4,0, usando tolueno como co-solvente. Esteviol foi produzido tanto usando pancreatina em pH 7,0 (20,2% de rendimento) quanto usando A. niger em pH 7,0 (20,8% de rendimento).

11.
Can J Microbiol ; 51(7): 541-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16175202

RESUMO

We evaluated the interaction between Punica granatum (pomegranate) methanolic extract (PGME) and antibiotics against 30 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). Susceptibility testing of the isolates to PGME and antibiotics was performed by the broth dilution method. Synergic activity was detected between PGME and the 5 antibiotics tested, chloramphenicol, gentamicin, ampicillin, tetracycline, and oxacillin, ranging from 38% to 73%. For some isolates, PGME did not interfere with the action of any of the antibiotics tested. The bactericidal activity of PGME (0.1 x MIC) in combination with ampicillin (0.5 x MIC) was assessed using chosen isolates by time-kill assays, and they confirmed the synergic activity. Using this combination, cell viability was reduced by 99.9% and 72.5% in MSSA and MRSA populations, respectively. PGME increased the post-antibiotic effect (PAE) of ampicillin from 3 to 7 h. In addition, PGME demonstrated the potential to either inhibit the efflux pump NorA or to enhance the influx of the drug. The detection of in vitro variant colonies of S. aureus resistant to PGME was low and they did not survive. In conclusion, PGME dramatically enhanced the activity of all antibiotics tested, and thus, offers an alternative for the extension of the useful lifetime of these antibiotics.


Assuntos
Antibacterianos/farmacologia , Lythraceae/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Contagem de Colônia Microbiana , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Humanos , Meticilina/farmacologia , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Staphylococcus aureus/crescimento & desenvolvimento
12.
J Ethnopharmacol ; 96(1-2): 335-9, 2005 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-15588686

RESUMO

In Brazil, pomegranate (Punica granatum L. (Punicaceae)) is widely used as a phytotherapeutic agent. This study evaluates the effect of pomegranate extract on Staphylococcus aureus FRI 722 growth and subsequent enterotoxin production. Bacterial susceptibility was determined by tube dilution method and production of enterotoxin was assessed using membrane-over-agar (MOA) plates. At a low extract concentration (0.01% v/v) bacterial growth was delayed, while a higher concentration (1% v/v) eliminated bacterial growth. Most interestingly, a 0.05% (v/v) concentration of extract was found to inhibit Staphylococcal enterotoxin (SE) A production. These data further implicate pomegranate extracts as potential antibacterial therapeutics with the added ability to inhibit enterotoxin production.


Assuntos
Antibacterianos/farmacologia , Enterotoxinas/antagonistas & inibidores , Lythraceae , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Enterotoxinas/biossíntese , Frutas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/crescimento & desenvolvimento , Fatores de Tempo
13.
Phytomedicine ; 10(2-3): 209-12, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12725579

RESUMO

Eighteen different extracts from five Annona species collected in Minas Gerais state, Brazil, were submitted to the brine shrimp lethality test in order to detect potential sources of novel cytotoxic, antitumor, pesticidal and anti-Trypanosoma cruzi compounds. All of the Annonaceous species tested showed good larvicidal activity as compared to a reference compounds and literature data.


Assuntos
Annonaceae , Artemia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Animais , Produtos Biológicos/farmacologia , Brasil , Larva/efeitos dos fármacos
14.
Fitoterapia ; 72(7): 854-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11677034

RESUMO

Tetrachyrin (1), 3alpha-tigloyloxykaur-16-en-19-oic acid (2) and 3alpha-cinnamoyloxykaur-16-en-19-oic acid (3) have been isolated from the ethanol extract of Wedelia paludosa aerial parts.


Assuntos
Asteraceae , Diterpenos/química , Fitoterapia , Extratos Vegetais/química , Humanos , Estruturas Vegetais
15.
Appl Microbiol Biotechnol ; 53(5): 601-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10855722

RESUMO

Methyl ent-17-hydroxy-16beta-kauran-19-oate was fed to a 2-day-old culture of the fungus Rhizopus stolonifer, fermenting at room temperature (25 degrees C) in an orbital shaker (21). After 11 days, both broth and mycelia were extracted with ethyl acetate. Two novel compounds were isolated from this experiment: methyl ent-9alpha,17-dihydroxy-16beta-kauran-19-oate and methyl ent-7alpha,17-dihydroxy-16beta-kauran-19-oate. Their structures were fully confirmed by spectroscopic methods.


Assuntos
Diterpenos/metabolismo , Rhizopus/crescimento & desenvolvimento , Rhizopus/metabolismo , Biotransformação , Meios de Cultura , Espectroscopia de Ressonância Magnética
16.
Phytochemistry ; 52(3): 397-400, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10501025

RESUMO

Microbial transformation of ent-kaur-16-en-19-oic acid was carried out with R. stolonifer. After seven days of incubation, two metabolites, ent-7 alpha-hydroxy-kaur-16-en-19-oic acid and ent-12 beta-hydroxy-kaur-9(11),16-dien-19-oic acid, were isolated as a result of hydroxylation and hydroxylation/dehydrogenation, respectively. Incubation for 15 days also afforded ent-16 beta,17-dihydroxy-kauran-19-oic acid. The metabolites were identified by spectroscopic methods.


Assuntos
Rhizopus/metabolismo , Biotransformação , Diterpenos/química , Diterpenos/farmacocinética , Estrutura Molecular , Análise Espectral
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