The effect of methanolic extract of Tamarindus indica Linn. on the growth of clinical isolates of Burkholderia pseudomallei.

Burkholderia pseudomallei (Pseudomonas pseudomallei) causes melioidosis, a life-threatening infection common among paddy cultivators in Southeast Asian countries. No plant materials have been investigated for its activity against B. pseudomallei. Therefore, a preliminary study was carried out using disc diffusion and minimum inhibitory concentration (MIC) methods to evaluate the anti-B. pseudomallei activity of five Indian medicinal plants documented to have been used for several ailments in the ancient Indian scriptures. The leaf extracts of Tamarindus indica, Lawsonia inermis, and Hibiscus rosa-sinensis, the rhizome extracts of Curcuma longa and the seeds of Vigna radiata were prepared using methanol as solvent. The disc diffusion and MIC methods were used to assess the anti-B. pseudomallei activity of the plants tested. Only methanol leaf extracts of Tamarindus indica exhibited anti-B. pseudomallei activity starting from disc concentrations of 150 mug by the disc diffusion method. The other plants failed to show any zone of inhibition. MIC assay revealed that the MIC and minimum bactericidal concentration (MBC) for B. pseudomallei were 125 mug/ml. Our preliminary finding showed that methanolic extracts of Tamarindus indica has anti-B. pseudomallei inhibitory potentials under in vitro conditions. Extensive animal studies may be required before investigating the role of Tamarindus indica for treating melioidosis.