Promising strategy to efficiently improve the kinsenoside and polysaccharide production of rhizome cultures of Anoectochilus roxburghii (Wall.) Lindl

Elicitation is an efficient strategy for enhancement of metabolite production during plant cell or organ culture. Salicylic acid (SA) and methyl jasmonate (MeJA) are the wildly used abiotic elicitors. To improve the accumulation of the kinsenoside and polysaccharides in rhizome cultures of Anoectochilus roxburghii (Wall.) Lindl., the present study added SA or MeJA to the culture medium after 30 days of rhizome suspension culture, and the effects of concentration and elicitation time of both elicitors on the kinsensode and polysaccharide accumulation were investigated. SA and MeJA efficiently enhanced contents of the bioactive compounds in concentration- and time-dependent manners. In SA groups, the maximum kinsenoside and polysaccharide contents were determined when rhizomes were treated with 500 μM SA for 12 days; in MeJA groups, kinsenoside and polysaccharide contents reached the highest levels when rhizomes were treated with 550 μM MeJA for 14 days and 16 days, respectively. In addition, the elicitation effects were compared in a large-scale bioreactor system. Kinsenoside and polysaccharide contents were markedly improved by elicitation with SA and MeJA compared with the un-elicited rhizomes and field-grown plants. The SA-treated group produced high kinsenoside (661.4 mg/g DW), which was 1.9-fold more than that from MeJA treatment. No significant difference was found in the polysaccharide content between SA and MeJA treatments. Thus, SA is a promising elicitor to economically improve the industrial production of kinsenoside and polysaccharides during rhizome culture of A. roxburghii.