Enhancement of polysialic acid yield by reducing initial phosphate and feeding ammonia water to <Emphasis Type="Italic">Escherichia coli</Emphasis> CCTCC M208088 |
| |
Authors: | Jian-Rong Wu Jin-Long Liu Xiao-Bei Zhan Chi-Chung Lin Hui Zhao |
| |
Institution: | 1.Key Laboratory of Industrial Biotechnology, School of Biotechnology, Ministry of Education,Jiangnan University,Wuxi,China |
| |
Abstract: | Polysialic acid (PSA) is a capsular polysaccharide obtained from aerobic fermentation with Escherichia coli. To enhance PSA production and eliminate the influence of phosphate on the PSA purification process, a lower level of initial
phosphate was adopted with pH control. The resulting PSA yield reached 4.1 g/L in fed-batch fermentation with 2.5 g/L K2HPO4 and E. coli strain CCTCC M208088. In addition, an ammonia water (NH4OH) feeding strategy to control the pH at 6.4 was developed resulting in PSA production that reached as high as 5.2 g/L. NMR
spectra confirmed the purified biopolymer as a α-2,8 linked PSA, identical to the published NMR spectra, with a molecular
weight in the range of 16 ∼ 50 kDa. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|