Application of a complete factorial design for the production of zeaxanthin by Flavobacterium sp.

Utilizing a four-liter fermentor and applying a complete factorial design 2 (3), the combined effects of agitation speed, aeration rate, and corn steep liquor concentration on zeaxanthin production by Flavobacterium sp. were s tudied. Maximum growth and production of total carotenoids and zeaxanthin w ere obtained at 600 rpm, 2 vvm and 4.6% corn steep liquor. Under these cond itions, zeaxanthin represented 86% of the total carotenoids produced. Lower values of the variables studied resulted in lower growth, volumetric produ ction of zeaxanthin and total carotenoids, and favored the formation of oth er carotenoids such as beta -carotene and canthaxanthin. The positive effec ts on growth and total carotenoids and zeaxanthin formation were in a large extent due to the interaction of agitation/corn steep liquor. However, aer ation also had a positive effect on growth.