Antimicrobial activity in vitro of plumbagin isolated from Plumbago species

Plumbagin is a naturally occurring naphthoquinone isolated from roots of Plumbago scandens. The plant was collected at the Campus of Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. P. scandens is used as a traditional medicine for the treatment of several diseases. The antimicrobial activity of plumbagin was evaluated using the macrodilution method. The compound exhibited relatively specific activity against bacteria and yeast. The minimum inhibitory concentration test showed the growth inhibiton of Staphylococcus aureus at a concentration of 1.56 æg/ml and of Candida albicans at a concentration of 0.78 æg/ml. These results suggest the naphthoquinone plumbagin as a promising antimicrobial agent.

Tolerância a antibióticos em cepas de Escherichia coli, Klebsiella pneumoniae e Staphylococcus aureus isoladas de pacientes do Hospital Universitário Antônio Pedro - HUAP / Tolerance to antibiotics among strains of Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus isolated from patients admitted into the Hospital Universitário Antônio Pedro - HUAP

A tolerância a antibióticos, medida através do critério: CMB/CMI > ou = 16, foi determinada em 157 cepas (Escherichia coli - 53, Klebsiella pneumoniae - 53 e Staphylococcus aureus - 51), isoladas de pacientes do HUAP, para os antibióticos amicacina (am), cefalotina (ce), cefoxitina (cx) e oxacilina (ox), de uso na antibioticoterapia do Hospital. Nenhuma tolerância foi verificada para os gram-negativos (E. coli e K. pneumoniae), enquanto para os isolados do gram-positivo (S. aureus), a tolerância foi encontrada e apresentou os seguintes percentuais: ox(21,6%, ce(11,8%), am(8,9%)e cx(2,0%)