THIDIAZURON ENHANCED REGENERATION AND SILYMARIN CONTENT IN SILYBUM MARIANUM L.

Abstract

Silybum marianum, of family Asteraceae is renowned for production of biologically important silymarin, which has shown multi-dimensional medicinal properties. It has a high protective role against jaundice and hepatitis C worldwide. We hereby established a feasible and efficient method for indirect regeneration of S. marianum for production of consistent plantlets. Calli were induced from leaf explants of seed-derived plantlets on Murashige and Skoog (MS) medium supplemented with several concentrations of different plant growth regulators (PGRs). Highest callogenic response (89%) was recorded for 4.4µM Thidiazuron (TDZ) in combination with 6.6µM Kinetin (Kn). Subsequent sub-culturing of callus after 4 weeks of culture, on medium with similar compositions of PGRs induced shoot organogenesis. Highest shoot induction frequency (86%) with maximum mean multiple shoots (26 shoots per explant) were recorded for 11µM TDZ after 4 weeks of transfer. Longest shoots (4.1 cm) were recorded for MS medium augmented with 6.6µM TDZ and 4.4µM αnaphthalene acetic acid (NAA). Furthermore, rooted plantlets were developed on MS medium containing different concentrations of indole acetic acid (IAA). Silymarin was determined by High performance liquid chromatography (HPLC) and 8.47 mg/g DW silymarin was detected in the regenerated plantlets. This study contributes to a better understanding of the different mechanisms involved in morphogenesis and production of biologically active principle in Silybum marianum.