Abstract: The experiments were purposed to investigate the effect of chitosan and yeast extract on Stemona
alkaloid production in Stemona sp. culture. Both elicitors enhanced Stemona alkaloid production over the
control. Treatment with chitosan at a concentration of 25 mg/L for 1 week resulted in the highest production
of Stemona alkaloids. It was found that 1', 2'-didehydrostemofoline and stemofoline production was 2.65 fold
and 2.95 fold higher than the control, respectively.