The biosynthesis of camptothecin derivatives by Camptotheca acuminata seedlings.

10-hydroxycamptothecin and 9-methoxycamptothecin, naturally occurring camptothecin derivatives, are reportedly present in Camptotheca acuminata with a powerful cytotoxic effect and strong antitumor activity. In this paper, we studied the derivatization reaction of camptothecin catalyzed by C. acuminata seedlings. HPLC traced the reaction between exogenous camptothecin and C. acuminata seedlings. The results showed that the exogenous camptothecin was converted into 10-hydroxycamptothecin and 9-methoxycamptothecin by the tender roots and stems of C. acuminata seedlings, which would be a new method for the synthesis of two camptothecin derivatives.