Catharanthus roseus tissue culture: the effects of medium modifications on growth and alkaloid production.

A number of nutritional factors as well as the growth factors 2,4-D and IAA were studied to determine their influence on growth and alkaloid formation in Catharanthus roseus suspension cultures. The optimal 2,4-D concentration for growth and alkaloid production was 1 mg/liter. With IAA, both 0.5 and 2.0 mg/liter in media produced tissue growth comparable to tissue receiving 1 mg/liter 2,4-D; however, qualitative and quantitative differences in alkaloid production were observed. Media formulations containing 2,4 and 6% sucrose showed proportionate increases in cell yield with increased sucrose, but concomitant decreases in alkaloid production. Suspension cultures in media containing 2, 5, and 10 times the normal level of phosphate exhibited little change in growth or alkaloid production. When thiamin HCl, yridoxine nicotinic acid and inositol were deleted from the medium, the tissue continued to grow well through the 24 month duration of the experiment; however, alkaloid production was altered quantitatively and qualitatively.