Draw-fill batch culture mode for production of xylanases by Cellulomonas flavigena on sugar cane bagasse.

Draw-fill culture was evaluated as a method for xylanase production by Cellulomonas flavigena on sugar cane bagasse. Specific xylanase activity and volumetric xylanase activities were measured by harvesting 50%, 55%, 60% and 70% of fermented broth at the end of each subculture. Maximum specific (64 IU mg(-1) protein) and volumetric (166 IU ml(-1)) xylanase activities were obtained by harvesting 50-55% of broth. Values were 3.4 and 3.8 times greater than those obtained in batch cultures carried out under the same conditions. Enzyme productivity of 4.2 IU ml(-1) h(-1) was significantly greater than that obtained in continuous cultures (2.4 IU ml(-1) h(-1)) (P<0.05).