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1.
Braz J Microbiol ; 47(1): 159-66, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26887239

RESUMO

A bioassay-guided fractionation of two samples of Brazilian red propolis (from Igarassu, PE, Brazil, hereinafter propolis 1 and 2) was conducted in order to determine the components responsible for its antimicrobial activity, especially against Candida spp. Samples of both the crude powdered resin and the crude ethanolic extract of propolis from both locations inhibited the growth of all 12 tested Candida strains, with a minimum inhibitory concentration of 256µg/mL. The hexane, acetate and methanol fractions of propolis 1 also inhibited all strains with minimum inhibitory concentration values ranging from 128 to 512µg/mL for the six bacteria tested and from 32 to 1024µg/mL for the yeasts. Similarly, hexane and acetate fractions of propolis sample 2 inhibited all microorganisms tested, with minimum inhibitory concentration values of 512µg/mL for bacteria and 32µg/mL for yeasts. The extracts were analyzed by HPLC and their phenolic profile allowed us to identify and quantitate one phenolic acid and seven flavonoids in the crude ethanolic extract. Formononetin and pinocembrin were the major constituents amongst the identified compounds. Formononetin was detected in all extracts and fractions tested, except for the methanolic fraction of sample 2. The isolated isoflavone formononetin inhibited the growth of all the microorganisms tested, with a minimum inhibitory concentration of 200µg/mL for the six bacteria strains tested and 25µg/mL for the six yeasts. Formononetin also exhibited fungicidal activity against five of the six yeasts tested. Taken together our results demonstrate that the isoflavone formononetin is implicated in the reported antimicrobial activity of red propolis.


Assuntos
Anti-Infecciosos/farmacologia , Candida/efeitos dos fármacos , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Própole/química , Anti-Infecciosos/isolamento & purificação , Bactérias/efeitos dos fármacos , Brasil , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Testes de Sensibilidade Microbiana
2.
Alkaloids Chem Biol ; 74: 233-409, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25845063

RESUMO

This chapter presents an overview of the chemistry and pharmacology of the alkaloids found in species of the Annonaceae family. The occurrence of alkaloids from Annonaceae species, as well as their chemical structures and pharmacological activities are summarized in informative and easy-to-understand tables. Within the Annonaceae family, the genera Annona, Duguetia, and Guatteria have led to many important publications. Valuable and comprehensive information about the structure of these alkaloids is provided. The alkaloids of the aporphine type represent the predominant group in this family. Many of the isolated alkaloids exhibit unique structures. In addition to the chemical structures, the pharmacological activities of some alkaloids are also presented in this chapter. Thus, the leishmanicidal, antimicrobial, antitumor, cytotoxic, and antimalarial activities observed for these alkaloids are highlighted. The chapter is presented as a contribution for the scientific community, mainly to enable the search for alkaloids in species belonging to the Annonaceae family.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Annonaceae/química , Alcaloides/classificação , Annona/química , Annonaceae/classificação , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Aporfinas/química , Aporfinas/farmacologia , Guatteria/química , Estrutura Molecular
3.
Artigo em Inglês | MEDLINE | ID: mdl-23346202

RESUMO

The objective of the study was to investigate the mechanism of the relaxant activity of the ent-15α-acetoxykaur-16-en-19-oic acid (KA-acetoxy). In rat mesenteric artery rings, KA-acetoxy induced a concentration-dependent relaxation in vessels precontracted with phenylephrine. In the absence of endothelium, the vasorelaxation was significantly shifted to the right without reduction of the maximum effect. Endothelium-dependent relaxation was significantly attenuated by pretreatment with L-NAME, an inhibitor of the NO-synthase (NOS), indomethacin, an inhibitor of the cyclooxygenase, L-NAME + indomethacin, atropine, a nonselective antagonist of the muscarinic receptors, ODQ, selective inhibitor of the guanylyl cyclase enzyme, or hydroxocobalamin, a nitric oxide scavenger. The relaxation was completely reversed in the presence of L-NAME + 1 mM L-arginine or L-arginine, an NO precursor. Diterpene-induced relaxation was not affected by TEA, a nonselective inhibitor of K+ channels. The KA-acetoxy antagonized CaCl(2)-induced contractions in a concentration-dependent manner and also inhibited an 80 mM KCl-induced contraction. The KA-acetoxy did not interfere with Ca(2+) release from intracellular stores. The vasorelaxant induced by KA-acetoxy seems to involve the inhibition of the Ca(2+) influx and also, at least in part, by endothelial muscarinic receptors activation, NO and PGI(2) release.

5.
Fitoterapia ; 75(3-4): 423-5, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15159013

RESUMO

The CHCl3 extract of Tillandsia recurvata yielded 5,3'-dihydroxy-6,7,8,4'-tetramethoxyflavanone (1), 1,3-di-O-cinnamoyl-glycerol (2) and ethyl ester of caffeic acid. Their structures were elucidated by means of spectroscopic methods such as mass spectroscopy and 1 and 2D-NMR.


Assuntos
Cinamatos/química , Flavanonas/química , Glicerol/química , Fitoterapia , Extratos Vegetais/química , Tillandsia , Glicerol/análogos & derivados , Humanos , Componentes Aéreos da Planta
6.
J Asian Nat Prod Res ; 6(1): 11-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14989375

RESUMO

A novel alkaloid named bowdichine (1), only the third with a diaza-adamantane skeleton containing an unusual N-acetyl enamine moiety, and the known alkaloids acosmine (2), ormosanine (3) and podopetaline (4) have been isolated from the stem bark of Bowdichia virgilioides. The structures were elucidated on the basis of spectral data, mainly 1D and 2D NMR of the diaza-adamantane alkaloids 1 and 2.


Assuntos
Adamantano/química , Adamantano/isolamento & purificação , Compostos Aza/química , Compostos Aza/isolamento & purificação , Fabaceae/química , Adamantano/análogos & derivados , Alcaloides/química , Alcaloides/isolamento & purificação , Espectroscopia de Ressonância Magnética
7.
Rev. bras. farmacogn ; 7/8(1): 41-47, 1998. tab, ilus
Artigo em Português | LILACS | ID: lil-534799

RESUMO

Neste trabalho foi verificado o teor de Óleos, sólidos e bixina em sementes de quatro variedades de Bixa orellana L. cultivadas na Paraíba: "Casca verde", "Casca vermelha", Bico de calango" e "Grão preto". Os melhores resultados foram obti­dos com os tipos "Casca verde" e "Casca vermelha" que apresentaram um rendimento em bixina pura, cristalina, de 1,3 e 1,1 por cento, respectivamente.


In this work it was verified the content of oils, solids and bixin in seeds of four varieties of Bixa orellana L. cultivated in Paraíba: "Casca verde", "Casca vermelha", Bico de calango" and "Grão preto". The best results were obtained with the types "Casca verde" and "Casca vermelha" that presented an yield in pure, crystalline bixina, of 1,3 and 1,1 percent, respectively.

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