Alkaloid production from cell suspension cultures obtained from osmotic-stressed callus lines of Catharanthus roseus

Catharanthus roseus callus cultures established were first exposed to osmotic stress using polyethylene glycol (9.0%, w/v)(MW 3350) in solid MS medium supplemented with 20 g/l sucrose, 2 mg/l ?-naphtalene acetic acid (NAA) and 3 mg/l 6-benzylamino purine (BAP). Cell suspensions were then initiated from stressed (S) and non-stressed (NS) calli in liquid LS medium. When LS medium was employed, only ajmalicine was detected at 1.308 µg/ml and 0.405 µg/ml concentrations for the S and NS cell lines, respectively. None of the other alkaloids normally found in the intact plant, such as vinblastine, vincristine and vindoline was detected at the end of experiments carried out with both media. From these results it can be concluded that, application of the osmotic stress to Catharanthus roseus cell suspension cultures increases ajmalicine production capacity, although it does not trigger the production of other alkaloids involved