ENHANCEMENT OF SECONDARY METABOLITE PRODUCTION BY IMMOBILIZED GOSSYPIUM-ARBOREUM CELLS

A novel reactor with simultaneous use of plant cell immobilization, pe rmeabilization, and elicitation was designed to enhance the productivi ty of secondary metabolites and to overcome Limitations of plant cell culture, such as slow metabolic rate, low product yield, and sensitivi ty to shear stresses. Production of gossypol, an antifungal agent, fro m Gossypium arboreum was selected as a model system. The effects of im mobilization, permeabilization, and elicitation on gossypol production were investigated in free suspension culture, immobilized plant cell reactor with recycled batch operation, and bioreactor with continuous operation. G. arboreum cells were effectively immobilized on a cotton matrix by entrapment with a spirally wound configuration. Permeabiliza tion of immobilized cells provided a tool for a continuous process inc reasing the release of gossypol by 30%, while the elicitation techniqu e played a major role to enhance productivity by more than 8-fold. In comparisons of productivity, continuous operation and combined treatme nt gave productivity: over 20-fold higher than batch culture. Simultan eous use of immobilization, permeabilization, and elicitation was poss ible in continuous operation with an immobilized plant cell reactor.