[Improved camptothecin production by cell lines of Camptotheca acuminata].

The concentration of camptothecin was determined in different tissues of Camptotheca acuminata seedling. The concentrations of camptothecin in new leaves and roots were significantly higher than in other tissues. However, the concentration of camptothecin declined with leaves becoming old. The induction of callus and cell suspension cultures from younger leaves of Camptotheca acuminata was observed. Cell lines were selected with improved camptothecin production as 0.02%.