Effect of culture conditions on the biosynthesis of gagaminine, a potent antioxidant from the roots of Cynanchum wilfordii

Gagaminine, a steroidal alkaloid isolated from the roots of Cynanchum wilfo rdii, exhibited potent inhibitory effects on the aldehyde oxidase activity and lipid peroxidation. To find a possible means of mass production of this active component, which will be useful for animal tests, we synthesized it by an in vitro culture method using various growth conditions. Calli were induced from the explants of this medicinal plant and cultivated under cult ure conditions which varied in light, and the kinds and concentration of pl ant growth regulators. The production of gagaminine was found to be signifi cantly higher in the dark than in the light. The best gagaminine content (0 .960%) was obtained after cultivation of stems on the medium containing 2,4 -dichlorophenoxyacetic acid (2,4-D, 2.0 mg/l) only. However, gagaminine was not detected by the mixture of 2,4-D and kinetin, while the mixtures of 2, 4-D/zeatin and 2,4-D/6-benzylaminopurine produced a low content of gagamini ne (<0.4%). In addition, suspension medium was much better for the formatio n of gagaminine than solid medium with an increase from 0.960 to 2.227% yie ld. These results suggest that gagaminine can be produced massively by in v itro culture using stems under the conditions of dark and 2,4-D on liquid m edium.