Study to isolate and enhance the production of potential antineoplastic secondary metabolites from selected medicinal plants with special reference to Ophiorrhiza Rugosa Var Decumbans

Abstract

Cancer is a group of disorders in which cells are aggressively growing without any checkpoints. The cancer research is an intense scientific effort to understand the disease process and to find novel therapeutic agents with fewer side effects. Camptothecin is a wellknown anticancer alkaloid originally isolated from Camptotheca acuminata by Wall and Wani in 1966. Due to its high demand, alternative sources are under intensive investigation. In the present study we emphasized the enhancement of the production of camptothecin from Ophiorrhiza rugosa var. decumbens through various biotechnological strategies and compared this with intact plants. For the production of camptothecin (CPT) from tissue cultures of O. rugosa, its shoot and root cultures were established in MS medium supplemented with NAA and BA. Methods such as elicitation, permeabilization were adopted for the enhancement of camptothecin in organ cultures. Effect of NAA and BA with respect to their concentrations were studied and found that a maximum production of 0.039% of dry weight in multiple shoot cultures and 0.065% of dry weight in root cultures by an HPLC unit with isocratic elution. Elicitors like methyl jasmonate and fungal cell wall extract were studied for their role in the elicitation of camptothecin. Methyl Jasmonate induced maximum production of camptothecin (1.14mg/gDW). The albino plants originated in the medium supplemented with high concentration of BA, was propagated in vitro for the CPT production. The amount of CPT exudated into the medium is also quantified. Ophiorrhiza genus is known for the presence of anthraquinone derivatives. From the tissue cultures of Ophiorrhiza rugosa var. decumbens, anthrquinones were isolated by column and thin layer chromatography. The separated-anthraquinone fraction was passed through a column filled with silica gel of 60-120 mesh and gradient elution of MeOH/CHCl3 was carried out. The 30ml fractions were collected and evaporated to dryness under vacuum.