Picrosides content in the rhizomes of Picrorhiza kurroa Royle ex Benth. traded for herbal drugs in the markets of North India

Picrorhiza kurroa Royle ex. Benth (Kutki) is an important medicinal plant used in various herbal drug formulations possessing hepatoprotective activity. Herbal drug industries purchase the raw plant material (dried rhizomes) of P. kurroa from the markets by judging the quality mainly on the basis of physical appearance of the rhizomes rather than the contents of active constituents. This study assessed the current status of trade and quality of P. kurroa plant material being sold in major herbal drug markets of north India (Delhi, Amritsar, Manali) on the basis of major chemical constituents i.e. P-I (Picroside-I) and P-II (Picroside-II) by using Reverse Phase HPLC (High Pressure Liquid Chromatography). The P. kurroa rhizomes sold in the Amritsar market contained highest picrosides content (10.9%) whereas sample from China (sold in Delhi market) showed the least amount of picrosides (2.8%). Various herbal drug formulations, containing P. kurroa as one of the constituents, were also analysed for picrosides content. The study highlights the importance of quality of raw material used in the preparation of herbal drug formulations.