Estimation of alkaloid content of Ashwagandha (Withania somnifera) with HPLC methods

Withania somnifera (Family; Solanaceae) is commonly known as Ashwagandha and is used in traditionally system of medicine since long time. Many compounds have been reported from the root part of the plant. In present study, comparative evaluation of microbial consortium and uninoculated control plant root collected from different geographically sources was done by HPLC. Methanol soluble root extract of the plant was subjected to Column chromatography to isolate and purify the phyto-constituents which can be termed as markers. Three compounds were isolated and purified. Compounds were characterized as withanone and withaferin-A. The third compound was found to be impure. Novel HPLC methods were developed for assessment of purity, for standardization and for estimation of the compounds. Simplicity of isolation and HPLC analysis for the compounds suggests that the compounds may be termed as markers for the standardization of the methanol extracts and preparations containing Withania somnifera

Effect of microbial consortium on plant growth and improvement of alkaloid content in Withania somnifera (Ashwagandha)

The effect of microbial consortium consisting Plant Growth Promoting Rhizobacteria (PGPR) like Azospirillum, Azotobacter, Pseudomonas and Bacillus were tested separately and in combination on Withania somnifera for two consecutive years (2009 and 2010). The combinations of above mentioned PGPR strains significantly increased plant height, root length, and alkaloid content in Withania somnifera when compared to the uninoculated control. Plant growth promoting rhizobacteria (PGPR) exhibit direct and indirect mechanisms as plant growth promoters and biological control agents. Direct mechanism by PGPR, include the provision of bio-available phosphorus for plant uptake, nitrogen fixation for plant. The results of this study suggest that the PGPR applied in combination have the potential to increase the plant growth, alkaloid content of Withania somnifera