关键词: 琥珀酸, 固定化发酵, 载体改性, 吸附, 聚乙烯亚胺

Abstract: Immobilization of Escherichia coli on cotton fiber modified by polyethylenimine coating and glutaraldehyde crossing-linking for succinic acid production was investigated. Compared with unmodified cotton fiber, static cell adhesion increased by 63.3% after the carrier was modified by PEI and GA. When 43 g/L glucose was put in fermentation medium, 120 g/L PEI-GA cotton fiber was added, and MgCO3 was used as neutralizer in batch fermentation, concentration of scuccinic acid was 29.6 g/L, productivity was 0.66 g/(L?h)and yield was 70.5%, increased by 11.3%, 37.5% and 7.5%, respectively. The batch fermentation of immobilized cells on PEI-GA cotton fiber was repeated seven times. The concentration of scuccinic acid, yield and productivity did not decrease. It suggested that PEI-GA cotton fiber as immobilization carrier was suitable for scuccinic acid production by Escherichia coli AFP111.

Key words: succinic acid, immobilized fermentation, modified carrier, adhesion, polyethylenimine