Biotechnological production of zeaxanthin by an Antarctic Flavobacterium: Evaluation of culture conditions

Abstract

Statistical experimental designs were used to formulate a culture medium for zeaxanthin production by an Antarctic Flavobacterium sp. P8 strain. Eleven nutritional factors were assayed in shaken flasks. The effect of temperature on zeaxanthin and carotenoid production was also studied. Peptone, yeast extract, and sodium chloride were the nutrients that caused the principal impact on the biomass growth. These components were further studied to enhance zeaxanthin and total carotenoid concentrations. Although a high production rate of zeaxanthin and carotenoids was achieved, the aerobic characteristics of the bacterial strain and the oxygen requirements for zeaxanthin biosynthesis incorporate a factor that requires additional consideration. Scaling up the process to a 5 L-bioreactor that increased dissolved oxygen availability resulted in a 4.5-fold increase in the total carotenoid content and an almost 9-fold increase in zeaxanthin, which represented 98% of the total carotenoids produced. The results reveal that Flavobacterium sp. P8 is a promising strain for zeaxanthin production.