Camptothecin production by in vitro cultures and plant regeneration in Ophiorrhiza species.

Camptothecin derivatives are clinically used for the treatment of various human cancers. These derivatives are semi-synthesized from camptothecin which is isolated from the extracts of Camptotheca acuminata and Nothapodytes foetida. For the feasible production of camptothecin, the protocols for the tissue cultures of Ophiorrhiza species, O. pumila, O. liukiuensis and O. kuroiwai, have been established. The established aseptic plants and hairy roots produced camptothecin, and O. pumila hairy roots accumulated highest amount of camptothecin. Furthermore, we have established methods of plant regeneration from O. pumila hairy roots.