Plant regeneration through direct and indirect organogenesis, phyto-molecular profiles, antioxidant properties and swertiamarin production in elicitated cell suspension cultures of Swertia minor (Griseb.) Knobl.

The present study reports an optimized protocol for high frequency in vitro plant propagation through direct and indirect organogenesis, phytochemical accumulation, molecular profiling and antioxidant evaluation for micropropagated Swertia minor, a promising alternative to industrially important Swertia chirayita. Moreover, the study also aimed at enhancing the production of antidiabetic and anti-obesity drug swertiamarin using an alternative technology of elicitated cell suspension cultures. Different types, concentrations and combination of cytokinins and auxins showed their effects during various in vitro growth stages. A combination of BAP (3.0 mg/l) and TDZ (1.0 mg/l) had a dominant role in promoting multiple shoot proliferation with production of an average of 19.1 ± 0.95 shoots/node in 85% response. MS medium added with IBA (2.0 mg/l) showed optimal response for in vitro rooting (9.2 ± 0.56 roots/shoot). In order to establish genetic stability, molecular marker-based profiling of micropropagated plants were done and 'monomorphic banding pattern were identical to the mother plants. 2,4-D (2.0 mg/l) supported the maximum callus induction and proliferation rate (95%). The wild-grown plants showed higher polyphenols content and antioxidant activities as compared to callus and in vitro derived plantlets. However, chitosan-treated (25 ppm) methanolic extract of cell biomass accumulated in cell suspension cultures produced higher contents of swertiamarin (1.45 mg/g DW) than salicylic acid and methyl jasmonate. The described protocol can be effectively used for the large-scale propagation, exploitation of active compounds and will serve as potential alternative to S. chirayita for fulfillment of over-growing industrial requirements. Key message: The present investigation addressed in vitro regeneration, callus culture, somatic embryogenesis, molecular profiling, secondary metabolite production, cell suspension culture studies for first time in Swertia minor. [ABSTRACT FROM AUTHOR]