文献类型：期刊文献

英文题名：Effect of oxygen and shear stress on molecular weight of hyaluronic acid produced by Streptococcus zooepidemicus

作者：Duan, Xu-Jie[1];Yang, Li[1];Zhang, Xu[1];Tan, Wen-Song[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2008

卷号：18

期号：4

起止页码：718

外文期刊名：JOURNAL OF MICROBIOLOGY AND BIOTECHNOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000255424600016)】；

语种：英文

外文关键词：oxygen; shear stress; hyaluronic acid; molecular weight; Streplococcus zooepidemicus

摘要：Dissolved oxygen (DO) and shear stress have pronounced effects on hyaluronic acid (HA) production, yet various views persist about their effects on the molecular weight of HA. Accordingly, this study investigated the effects of DO and shear stress during HA fermentation. The results showed that both cell growth and HA synthesis were suppressed under anaerobic conditions, and the HA molecular mass was only (1.22 +/- 0.02) x 10(6) Da. Under aerobic conditions, although the DO level produced no change in the biomass or HA yield, a high DO level favored the HA molecular mass, which reached a maximum value of (2.19 +/- 0.05) x 10(6) Da at 50% DO. Furthermore, a high shear stress delayed the rate of HA synthesis and decreased the HA molecular weight, yet had no clear effect on the HA yield. Therefore, a high DO concentration and mild shear environment would appear to be essential to enhance the HA molecular weight.