Abstract

Ginsenoside Rb₁ is one of the principal pharmacological ingredients of ginseng. The effects of Amaranthus tricolor suspension cells, containing high level of squalene, on ginsenoside Rb₁ production by Panax ginseng suspension cells were investigated. The maximum Rb₁ content (51.5 ± 3.1 mg/L) reached during the next 4 d after A. tricolor cells (16 g fresh weight /L) were added into P. ginseng suspension cell cultures on day 16 of cultivation, which was around 2-fold that in control. The activity of ginsenoside Rb₁ synthase was increased by 1.6 fold at this point. At the same time, addition of A. tricolor cells increased the content of squalene, a precursor of ginsenoside Rb₁, in the culture medium of P. ginseng suspension cell cultures. Feeding squalene (10 mg/L) led to a 16 ± 0.9% increase in ginsenoside Rb₁ production. The observation suggested that the enhanced Rb₁ production resulted from that the A. tricolor cells invoked the ginsenoside Rb₁ synthase and supplied the precursor squalene. Rational utilization of suspension cell co-culture could be a novel tactic for improving ginsenoside production by cell cultures.

Key words: Ginsenoside Rb₁, Panax ginseng, ginsenoside Rb₁ synthase,Amaranthus tricolor, plant cell suspension culture.