Elicitors' influenced differential ginsenoside production and exudation into medium with concurrent Rg3/Rh2 panaxadiol induction in Panax quinquefolius cell suspensions.

Cobalt nitrate, nickel sulphate, hydrogen peroxide, sodium nitroprusside, and culture filtrates of Pseudomonas monteili, Bacillus circularans, Trichoderma atroviridae, and Trichoderma harzianum were tested to elicit ginsenoside production in a cell suspension line of Panax quinquefolius. Abiotic elicitors preferentially increased panaxadiols whereas biotic elicitors upregulated the panaxatriol synthesis. Cobalt nitrate (50 μM) increased total ginsenosides content by twofold (54.3 mg/L) within 5 days. It also induced the Rc synthesis that was absent in the control cultures. Elicitation with P. monteili (2.5 % v/v, 5 days) also supported 2.4-fold enhancement in saponin yield. Elicitation by T. atroviridae or hydrogen peroxide induced the synthesis of Rg3 and Rh2 that are absent in ginseng roots. The highest ginsenosides productivity (3.2-fold of control) was noticed in cells exposed to 1.25 % v/v dose of T. atroviridae for 5 days. Treating cells with T. harzianum for 15 days afforded maximum synthesis and leaching (8.1 mg/L) of ginsenoside Rh1.