an effective biotic elicitor for improving biosynthesis of
secondary metabolites and the stimulation was found to
associate with the key enzyme in the biosynthesis (Cheng
et al., 2006). In several other plant species, chitosan has
been shown to be a powerful elicitor to produce secondary
metabolites. A study of effect of chitosan on Rubia akane
Nakai cell culture indicated that 25 mg/L of chitosan was
the optimal concentration for anthraquinone production.
The total anthraquinone production was approximately