Registro completo |
Provedor de dados: |
BJMBR
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País: |
Brazil
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Título: |
Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum
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Autores: |
Tanaka,J.C.A.
Silva,C.C. da
Oliveira,A.J.B. de
Nakamura,C.V.
Dias Filho,B.P.
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Data: |
2006-03-01
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Ano: |
2006
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Palavras-chave: |
Aspidosperma ramiflorum
Antibacterial activity
Monoterpenoid indole alkaloids
Ramiflorines A and B
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Resumo: |
We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37ºC and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 µg/mL) and S. aureus (MIC = 500 µg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 µg/mL). Fractions I and II were inactive against standard strains at concentrations of <=1000 µg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 µg/mL) and S. aureus (MIC = 250 µg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 µg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 µg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 µg/mL) and S. aureus (MIC = 31.3 µg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 µg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 µg/mL) and E. faecalis (MIC = 50 µg/mL), with EC50 of 8 and 2.5 µg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.
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Tipo: |
Info:eu-repo/semantics/other
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Idioma: |
Inglês
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Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2006000300009
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Editor: |
Associação Brasileira de Divulgação Científica
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Relação: |
10.1590/S0100-879X2006000300009
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Formato: |
text/html
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Fonte: |
Brazilian Journal of Medical and Biological Research v.39 n.3 2006
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Direitos: |
info:eu-repo/semantics/openAccess
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