Cinchona cells performance in in vitro culture: quinine alkaloid production with application of different elicitors

Abstract

Abstract Quinine is a dominant alkaloid in Cinchona ledgeriana. It is widely used in anti-malaria, anti-cramping, and anti-arrhythmia medication. In addition, it is commercially demanded for its bitter taste in certain soft drinks. The main source of quinine is the bark of Cinchona plant, which consists of 4-7% of the alkaloid. Land use shifting from perennial trees to cash-crops has resulted in a shortage of the plant material for quinine extraction. Plant cell culture has proven its success in producing secondary metabolites, including alkaloids. In principle, plant cells synthesize secondary metabolites when they are exposed to stress conditions. Therefore, in cell culture of C. ledgeriana, two stress-inducing agents i.e. abscisic acid (ABA) and paclobutrazol (PBZ) in combination with mannitol or sorbitol were applied to increase quinine yield. ABA and PBZ depressed the cells growth. Sorbitol caused more stress to cells than mannitol. Its combination with ABA 3 mgL−1 or with PBZ 7 mgL−1, mixed three weeks after culture, produced the highest concentration of quinine followed by mannitol with ABA 3 mgL−1 or PBZ 7 mgL−1 combined at the third week after culture. Cultured cells showed three different shapes: round, oval, and elongated. The elongated shape pre-dominated in the mature cells culture, while round cells pre-dominated in young cells culture. Those mature cells were found to contain alkaloids.