title: Fed-batch production of a bioflocculant from Corynebacterium glutamicum.
abstract: The constant-rate fed-batch production of the polygalacturonic acid bioflocculant REA-11 was studied. A controlled sucrose-feeding strategy resulted in a slight improvement in biomass and a 7% reduction in flocculating activity compared with the batch process. When fed with a 3 g l(-1) urea solution, the flocculating activity was enhanced to 720 U ml(-1) in 36 h. High cell density (2.12 g l(-1)) and flocculating activity (820 U ml(-1)) were obtained in a 10-l fermentor by feeding with a sucrose-urea solution, with values of nearly two times and 50% higher than those of the batch process, respectively. Moreover, the residual sucrose declined to 2.4 g l(-1), and residual urea decreased to 0.03 g l(-1). Even higher flocculating activity of 920 U ml(-1) and biomass of 3.26 g l(-1) were obtained by feeding with a sucrose-urea solution in a pilot scale fermentation process, indicating the potential industrial utility of this constant-rate feeding strategy in bioflocculant production by Corynebacterium glutamicum.
authors.affiliation: Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, People's Republic of China.
authors.forename: Haijun
authors.initials: H
authors.lastname: Wu
authors.forename: Qingbiao
authors.initials: Q
authors.lastname: Li
authors.forename: Rui
authors.initials: R
authors.lastname: Lu
authors.forename: Yuanpeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Zhuang
authors.forename: Ning
authors.initials: N
authors.lastname: He
mesh_terms: D018533:Biomass; D019149:Bioreactors; D048230:Corynebacterium glutamicum / Q000378:metabolism*; D017077:Culture Media, Conditioned / Q000737:chemistry; D005285:Fermentation; D005427:Flocculation; D005818:Genetic Engineering; D005947:Glucose / Q000378:metabolism; D010368:Pectins / Q000096:biosynthesis*; D013395:Sucrose / Q000378:metabolism; D014508:Urea / Q000378:metabolism
chemical_list: D017077:Culture Media, Conditioned; D013395:Sucrose; D010368:Pectins; D014508:Urea; D005947:Glucose; C003181:polygalacturonic acid