Biosynthetic Machinery of Iridoid Glycosides the Major Pharmacological Components of a Medicinal Herb Picrorhiza Kurroa Royle ex Benth

Abstract

Picrorhiza kurroa possesses a broad range of pharmacological activities which are attributed to the presence of iridoid glycosides Picroside I P I and Picroside II PII. P. kurroa has been collected recklessly for its underground parts from the wild as a result putting it in the category of endangered species. Herbal drug industries purchase raw plant material dried rhizomes of P. kurroa from markets on the basis of physical appearance of the rhizomes rather than their chemical constituents. The biosynthetic machinery of major medicinal components Picroside I and Picroside II is poorly understood. Thus any genetic intervention strategy for enhanced production of picrosides would require knowledge on complete biosynthetic pathway and key control points. The current study therefore investigated i quality assessment of P. kurroa raw material from major herbal drug markets of NorthIndia ii determination of chemotypic variation among accessions from different geographical locations iii mapping genes to enzymatic steps in complete biosynthetic pathway of Picroside I and Picroside II iv discerning the relative contribution of MEP/MVA pathway to the biosynthesis of PicrosideI and PicrosideII and iv determination of genetic variation among P. kurroa accessions from different geographical locations. newline