Predominance of oleanane-type ginsenoside R0 and malonyl esters of protopanaxadiol-type ginsenosides in the 20-year-old suspension cell culture of Panax japonicus C.A. Meyer

Abstract

Cell culture of Panax spp. is a potent sustainable source of biologically active triterpene glycosides (ginsenosides) specific for this genus. In this study, growth and biosynthetic profiles were investigated for P. japonicus suspension cell culture maintained for over 20 years by periodic subcultures in flasks. Cell culture demonstrated intensive growth evidenced by high accumulation of dry weight (DW, 9.8 gL−1), viability (80–90%) and specific growth rate (0.12 day−1) that were comparable to those recorded at the year of culture induction. Nineteen structurally different ginsenosides were identified in cell biomass using UPLC-Q-Exactive-Orbitrap HRMS and HPLC-ESI-Q-MS. Ginsenoside R0 and malonyl-ginsenosides (MalGs) accounted for over 80% of the total ginsenoside content in cells during the subculture cycle while the sum of neutral ginsenosides of protopanaxatriol (PPT: Re, Rg1, Rf) and protopanaxadiol (PPD: Rb1, Rb2, Rc, Rd) groups constituted less than 20%. Ginsenoside contents were maximized during growth decline phase as 35.3 mg/gDW for R0, 48.7 mg/gDW for MalGs, 10.4 mg/gDW for PPD and 5.2 mg/gDW for PPT. These data confirmed that 20-year-old cell culture of P. japonicus retained the ability for intensive growth and accumulation of wide spectrum of ginsenosides which opens the door for wide application of this culture.