Development of a Cell Culture Technology for Rapid Multiplication and Production of a Medicinal Compound Picroside 1 in an Endangered Herb Picrorhiza kurroa Royle ex Benth

Abstract

P. kurroa Royle ex Benth (Family: Scrophulariaceae) is a medicinal herb mainly found in the North-Western Himalayas at altitudes of 3000-4300 meters. P. kurroa is a well-known herb in the Ayurvedic system of medicine and has traditionally been used to treat disorders of the liver and upper respiratory tract, reduce fevers, treat dyspepsia, chronic diarrhea, scorpion sting, etc. A commercial formulation named as Picroliv has been prepared from P. kurroa extracts containing Picroside-1 as the main component and has been launched as a highly effective hepatoprotective drug (Ansari et al. 1991; Dwivedi et al. 1997). The reckless collection of P. kurroa has reduced its populations to a very low levels resulting in its categorization as an endangered spcies, thereby, warranting the development of alternative strategies for the conservation and production of metabolites of medicinal value. The persual of literature revealed that there are few reports on tissue culture of P. kurroa that too mainly on micropropagation with no success in transferring the plants to field conditions (Lal et al.1988; Uppadhay et al. 1989) andno report on optimization of tissue culture conditions for in vitro production of picrosides in P. kurroa. We have carried out preliminary experiments on tissue culture of P. kurroa to optimize nutrient media and incubation condtions for obtaining tissue culture plants with vigorous growth as well as a tissue culture process for in vitro production of Picroside-I and Picroside-II. All the tissue culture work done in P. kurroa have incubated cultures at 25±1oC, which is most commonly used in tissue cultures of other plant species. We observed that the P. kurroa plants formed at 25±1oC were very thin, slender and unable to survive in the field conditions. Also, there was no accmulation of Picroside-I and Picroside-II in the cultures incubated at 25±1oC. Testing of various media modifications did not help to induce vigorous growth in shoots of P. kurroa.