Safety evaluation of Picrorhiza kurroa rhizome extract by bacterial reverse mutation test

Picrorhiza kurroa is a recognized herb in the Ayurvedic and Chinese system of traditional medicine. It is effective in treating a variety of diseases ranging from digestion problems to paralysis. Thus it is essential to rule out any kind of toxicity, mutagenicity or carcinogenicity in the plant to be used as a medicine. The study was conducted to evaluate ability of Picrorhiza kurroa to induce reverse mutations at the histidine locus in several strains of Salmonella typhimurium in the absence or presence of exogenous metabolic activation system (S9) containing microsomal enzymes. The bacterial reverse mutation assay has been shown to be a sensitive, rapid and accurate indicator of mutagenic activity of a wide range of chemical classes. All bacterial strains showed negative responses over the entire dose range. No significant dose related increase was observed in the number of revertants in the two independent experiments. Based on the results 128 Acharya Balkrishna et al. of this study it is concluded that Picrorhiza kurroa rhizome extract is not mutagenic in the Salmonella typhimurium reverse mutation assay.