Cryopreservation of periwinkle, Catharanthus roseus cells cultured in vitro.

UNLABELLED: A procedure for prolonged cryogenic storage of periwinkle cell cultures is described. Cells derived from periwinkle, Catharanthus roseus (L.) G. Don, and subcultured as suspension in 1-B5C nutrient medium have been frozen, stored in liquid nitrogen (-196°C) for 11 weeks, thawed and recultured. Maximal survival was achieved when 3-4 day-old cells precultured for 24 h in nutrient medium with 5% DMSO were frozen at slow cooling rates of 0.5 or 1°C/min prior to storage in liquid nitrogen. The only loss in viability of cells occurred subsequent to treatment with DMSO. ABBREVIATIONS: DMSO, dimethylsulfoxide; 2,4-D, 2,4-dichlorophenoxyacetic acid; TTC, triphenyltetrazolium chloride.