Antimicrobial evaluation of Pathyashadangam kwath, a classical Ayurvedic polyherbal formulation

Abstract

Pathyashadangam kwath, a polyherbal formulation prepared from pathya, aksa, dhatri, bhunimba, nisa, nimba and amrita has been prescribed by Ayurveda physicians from time immemorial for the treatment of multitude of diseases including upper respiratory tract infections. A number of secondary metabolites isolated from ingredients of the kwath have been reported to have antimicrobial properties. But no reports on antimicrobial evaluation of the formulation is available as on date. Hence an effort has been made to evaluate the antimicrobial effectiveness of Pathyashadangam kwath against specific microbes.Three batches of Pathyashadangam kwath were prepared, following the standard procedures described in the kwatha vidhi of Sarngadhara Samhita, an ancient Ayurvedic text. Pure cultures of Gram-positive bacteria namely Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis, Gram - negative bacteria like Pseudomonas aeruginosa, Klebsiella pneumoniae subsp.pneumoniae, Salmonella enterica typhimurium and fungal strain Candida albicans were procured from MTCC Chandigarh. Antimicrobial evaluation of the formulation was done by agar well diffusion assay and minimum inhibitory concentration by Resazurin based micro titer dilution assay.Antimicrobial assays revealed that the kwath has substantial antimicrobial potential against all the three Gram positive bacteria and yeast strain, Candida albicans and moderate activity against Gram negative bacterium, Pseudomonas aeruginosa. Gram negative bacteria, Klebsiella pneumoniae subsp.pneumoniae and Salmonella enterica typhimurium were found to be resistant to the tested dose of kwath. Resazurin based microtitre dilution assay revealed that low concentrations of Pathyashadangam kwath could inhibit the growth of Gram-positive bacteria and fungi, but higher concentrations were required to inhibit Gram-negative bacteria.From the study it was concluded that Pathyashadangam kwath has significant antimicrobial potential which contributes to its therapeutic efficacy.