The oxygen transfer rate influences the molecular mass of the alginate produced by Azotobacter vinelandii

被引：44

作者：

Diaz-Barrera, A. ^{[1
]}

Pena, C. ^{[1
]}

Galindo, E. ^{[1
]}

机构：

[1] Univ Nacl Autonoma Mexico, Inst Biotechnol, Dept Ingn Celular & Biiocatalisis, Cuernavaca 62250, Morelos, Mexico

来源：

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY | 2007年 / 76卷 / 04期

关键词：

oxygen transfer rate; alginate; molecular mass; oxygen limitation;

D O I：

10.1007/s00253-007-1060-3

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

The influence of oxygen transfer rate (OTR) on the molecular mass of alginate was studied. In batch cultures without dissolved oxygen tension (DOT) control and at different agitation rates, the DOT was nearly zero and the OTR was constant during biomass growth, hence the cultures were oxygen-limited. The OTR reached different maximum levels (OTRmax) and enabled to establish various relative respiration rates. Overall, the findings showed that OTR influences alginate molecular mass. The mean molecular mass (MMM) of the alginate increased as OTRmax decreased. The molecular mass obtained at 3.0 mmol l(-1)h(-1)supercript stop was 7.0 times higher (1,560 kDa) than at 9.0 mmol l(-1)h(-1) (220 kDa). An increase in molecular mass can be a bacterial response to adverse nutritional conditions such as oxygen limitation.

引用

页码：903 / 910

页数：8

共 38 条

[1] Online respiration activity measurement (OTR, CTR, RQ) in shake flasks [J].