RESUMO
In vitro tests conducted with extracts rich in tannins have identified several biological activities of this class of substance. Thus, this paper intends to evaluate the antibacterial activity of tannin-rich fraction obtained from leaf extracts of Anacardium humile A.St.-Hil. Extracts of A. humile leaves in 70% acetone were semi-purified with ethyl acetate and butanol. We quantified the total tannins of the semi-purified fractions, of the crude extract and of aqueous residues and then performed tests of the antibacterial activity of the tannins against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. All positive extracts underwent tannin isolation using a Sephadex LH-20 column. The tannins isolated from the samples were quantified and tested for the minimal inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The tannins from crude extracts, semi-purifications and residues showed inhibition of S. aureus growth with MIC=500 g mL-1. All tannin fractions showed MIC against all strains and MBC, except against E. faecalis. The tannin fractions from Anacardium humile have antibacterial activity against Staphylococcus aureus, Pseudomononas aeruginosa and Enterococcus faecalis and, therefore, may be promising for future synthesis of new antibacterial agents.
Testes in vitro realizados com extratos ricos em taninos têm identificado muitas atividades biológicas dessa classe de substâncias. Nesse contexto, esse artigo propõe a avaliação da atividade antibacteriana de frações tânicas, obtidas de extratos de folhas de Anacardium humile A.St.-Hil. Extratos de A. humile em acetona 70% foram particionados com acetato de etila e butanol. Foram quantificados taninos totais das frações particionadas, do extrato bruto e dos resíduos aquosos, e foi realizado teste de atividade antibacteriana dos taninos contra Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 e Enterococcus faecalis ATCC 29212. Todos os extratos positivos foram submetidos ao isolamento de taninos, utilizando-se coluna de Sephadex LH-20. Os taninos isolados das amostras foram quantificados e testados sua concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Os taninos do extrato bruto, partições e resíduos apresentaram inibição do crescimento de S.aureus com CIM =500 g mL-1. As frações tânicas apresentaram CIM contra todas as cepas e CBM, exceto contra E. faecalis. As frações tânicas de Anacardium humile possuem atividade antibacteriana contra Staphylococcus aureus, Pseudomononas aeruginosa e Enterococcus faecalis e, portanto, podem ser promissoras em sínteses futuras de novos agentes antimicrobianos.
RESUMO
In vitro tests conducted with extracts rich in tannins have identified several biological activities of this class of substance. Thus, this paper intends to evaluate the antibacterial activity of tannin-rich fraction obtained from leaf extracts of Anacardium humile A.St.-Hil. Extracts of A. humile leaves in 70% acetone were semi-purified with ethyl acetate and butanol. We quantified the total tannins of the semi-purified fractions, of the crude extract and of aqueous residues and then performed tests of the antibacterial activity of the tannins against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. All positive extracts underwent tannin isolation using a Sephadex LH-20 column. The tannins isolated from the samples were quantified and tested for the minimal inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The tannins from crude extracts, semi-purifications and residues showed inhibition of S. aureus growth with MIC=500 g mL-1. All tannin fractions showed MIC against all strains and MBC, except against E. faecalis. The tannin fractions from Anacardium humile have antibacterial activity against Staphylococcus aureus, Pseudomononas aeruginosa and Enterococcus faecalis and, therefore, may be promising for future synthesis of new antibacterial agents.
Testes in vitro realizados com extratos ricos em taninos têm identificado muitas atividades biológicas dessa classe de substâncias. Nesse contexto, esse artigo propõe a avaliação da atividade antibacteriana de frações tânicas, obtidas de extratos de folhas de Anacardium humile A.St.-Hil. Extratos de A. humile em acetona 70% foram particionados com acetato de etila e butanol. Foram quantificados taninos totais das frações particionadas, do extrato bruto e dos resíduos aquosos, e foi realizado teste de atividade antibacteriana dos taninos contra Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 e Enterococcus faecalis ATCC 29212. Todos os extratos positivos foram submetidos ao isolamento de taninos, utilizando-se coluna de Sephadex LH-20. Os taninos isolados das amostras foram quantificados e testados sua concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Os taninos do extrato bruto, partições e resíduos apresentaram inibição do crescimento de S.aureus com CIM =500 g mL-1. As frações tânicas apresentaram CIM contra todas as cepas e CBM, exceto contra E. faecalis. As frações tânicas de Anacardium humile possuem atividade antibacteriana contra Staphylococcus aureus, Pseudomononas aeruginosa e Enterococcus faecalis e, portanto, podem ser promissoras em sínteses futuras de novos agentes antimicrobianos.
RESUMO
In vitro tests conducted with extracts rich in tannins have identified several biological activities of this class of substance. Thus, this paper intends to evaluate the antibacterial activity of tannin-rich fraction obtained from leaf extracts of Anacardium humile A.St.-Hil. Extracts of A. humile leaves in 70% acetone were semi-purified with ethyl acetate and butanol. We quantified the total tannins of the semi-purified fractions, of the crude extract and of aqueous residues and then performed tests of the antibacterial activity of the tannins against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. All positive extracts underwent tannin isolation using a Sephadex LH-20 column. The tannins isolated from the samples were quantified and tested for the minimal inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The tannins from crude extracts, semi-purifications and residues showed inhibition of S. aureus growth with MIC=500 g mL-1. All tannin fractions showed MIC against all strains and MBC, except against E. faecalis. The tannin fractions from Anacardium humile have antibacterial activity against Staphylococcus aureus, Pseudomononas aeruginosa and Enterococcus faecalis and, therefore, may be promising for future synthesis of new antibacterial agents.
Testes in vitro realizados com extratos ricos em taninos têm identificado muitas atividades biológicas dessa classe de substâncias. Nesse contexto, esse artigo propõe a avaliação da atividade antibacteriana de frações tânicas, obtidas de extratos de folhas de Anacardium humile A.St.-Hil. Extratos de A. humile em acetona 70% foram particionados com acetato de etila e butanol. Foram quantificados taninos totais das frações particionadas, do extrato bruto e dos resíduos aquosos, e foi realizado teste de atividade antibacteriana dos taninos contra Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 e Enterococcus faecalis ATCC 29212. Todos os extratos positivos foram submetidos ao isolamento de taninos, utilizando-se coluna de Sephadex LH-20. Os taninos isolados das amostras foram quantificados e testados sua concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Os taninos do extrato bruto, partições e resíduos apresentaram inibição do crescimento de S.aureus com CIM =500 g mL-1. As frações tânicas apresentaram CIM contra todas as cepas e CBM, exceto contra E. faecalis. As frações tânicas de Anacardium humile possuem atividade antibacteriana contra Staphylococcus aureus, Pseudomononas aeruginosa e Enterococcus faecalis e, portanto, podem ser promissoras em sínteses futuras de novos agentes antimicrobianos.
RESUMO
(-)-Hinokinin, a dibenzylbutyrolactone lignan, exhibits significant trypanocidal activity both in vitro and in vivo, and was obtained by partial synthesis from (-)-cubebin isolated from the dry seeds of Piper cubeba. Considering the good trypanocidal activity of (-)-hinokinin, as well as its potential for the development of new drugs, it is extremely important to evaluate its possible mutagenic activity to allow its safe use in humans. In the present study, we evaluated the antimutagenic effect of (-)-hinokinin on the chromosome damage induced by the chemotherapeutic agent doxorubicin (DXR). The test system employed was the analysis of micronucleated polychromatic erythrocytes in peripheral blood of Wistar rats. Additionally, the antioxidant activity of (-)-hinokinin was evaluated in in vitro experiments by measuring the production of hydrogen peroxide and other peroxides. Our results showed that animals treated with different doses of (-)-hinokinin (10, 20, and 40mg/kgb.w.) exhibited micronucleated cell frequencies similar to that of the negative control. In addition, treatment with combinations of (-)-hinokinin and DXR resulted in lower micronucleated cell frequencies than those observed for animals treated with DXR alone. The present study shows that (-)-hinokinin not only has no genotoxic effect, but is also effective in reducing the chromosome damage induced by DXR. (-)-Hinokinin exerted a significant antioxidant effect on parasite mitochondria in the protocol used, which might be one possible mechanism by which this compound may exert a protective effect on the chromosome damage induced by the free radicals generated by DXR.