Permeabilization of Cinchona ledgeriana cells by dimethylsulphoxide. effects on alkaloid release and long-term membrane integrity.

Dimethyl sulphoxide (DMSO) has been used to permeabilize cells of Cinchona ledgeriana in suspension culture and promote the release of intracellular alkaloids. 5-6% v/v is required before any release is seen, and greater than 20% DMSO is required for full release. Even at these high levels of DMSO release is slow, taking in excess of seven hours to reach completion. Conditions which produce significant release of alkaloids have a deleterious effect on cells. Many of the membranes permeabilized did not recover their ability to selectively exclude compounds such as mannitol when the DMSO was removed. It is concluded that DMSO is not a suitable material for inducing alkaloid release in any biotechnological exploitation of alkaloid production by C. ledgeriana.