Ag+-induced silymarin production in cell suspension culture of Silybum marianum L. Gaertn

Abstract

Silymarin production in cell suspension culture of Silybum marianum treated with Ag+ was investigated. It is well known that elicitation is one of the strategies employed to increase accumulation of secondary metabolites (1). Callus induction was initiated from cotyledon segments of seedlings on MS medium supplemented with picloram (3mg l–1) and kinetin (0.4mg l–1). Cell suspensions were established from 1-month-old undifferentiated callus and maintained in darkness in MS liquid medium and were incubated on a rotary shaker cultures (150 rpm) and 25°C (1 and 2). Cell suspension cultures of S. marianum were exposed to various levels of Ag+ (0.2, 0.4, 0.8, 1 and 2 mM) and harvested 12, 24, 48, 72, 144 and 216 hr after treatment. The highest silymarin production reached about 60µg g-1Dw, 24 hours after treatment with Ag+ (0.8mM), witch was 30-fold that of the control. Therefore cell suspension culture of S. marianum are susceptible to elicitation by Ag+ and the information obtained in this work is useful for efficient large-scale production of silymarin by cell suspension culture of S.marianum.