A fungal mycelium elicitor efficiently improved ginsenoside synthesis during adventitious root culture of Panax ginseng

To select an effective and economic elicitor for the production of ginsenosides by adventitious root culture of Panax ginseng C.A. Mey, this study used mycelia of the pathogenic fungi Alternaria panax as a biotic elicitor to investigate effects of elicitor concentrations and elicitation duration on ginsenoside accumulation; the elicitation effect of mycelia and its extract as well as methyl jasmonate was also compared. The concentrations of the mycelium elicitor and elicitation duration significantly affected ginsenoside accumulation, and the maximum ginsenoside contents were obtained when 30-day-old adventitious roots were treated with 200 mg/L mycelium elicitor for 8 days. In comparison experiment, ginsenoside accumulation of mycelium elicitor was similar to that of the mycelium extract elicitor and approximately 25 mg/g DW of ginsenoside content was obtained, which was significantly higher (p < 0.05) than that of methyl jasmonate. Consequently, the mycelium was considered to be the more suitable elicitor because it can effectively improve ginsenoside accumulation with easily and simply preparing. The finding of the present study suggested that the mycelia of Alternaria panax can be used as an economic elicitor during adventitious root culture of Panax ginseng for the commercial production of ginsenosides in the future.