Barker P E, Ajongwen N J
Department of Chemical Engineering and Applied Chemistry, University of Aston, Birmingham, England.
Biotechnol Bioeng. 1991 Apr 5;37(8):703-7. doi: 10.1002/bit.260370803.
High yields of the enzyme dextransucrase have been produced repeatedly by fed-batch fermentation techniques. Activities in excess of 21.9 U/cm(3) have been obtained by culturing Leuconostoc mesenteroides NRRL B-512(F) under nonaerated fed-batch fermentation conditions. Aerobic fermentations carried out under identical conditions have consistently produced enzyme of less than 17 U/cm(3), but with no difference in the final cell concentration in the broth. Different types of yeast extract have been found to have significant effect on the final cell concentration and more especially on the enzyme activity with enzyme yields varying by as much as 50% when different types of yeast extracts were used.
通过补料分批发酵技术已多次获得高产量的右旋糖酐蔗糖酶。在非曝气补料分批发酵条件下培养肠系膜明串珠菌NRRL B - 512(F),已获得超过21.9 U/cm³的活性。在相同条件下进行的需氧发酵一直产生低于17 U/cm³的酶,但肉汤中的最终细胞浓度没有差异。已发现不同类型的酵母提取物对最终细胞浓度有显著影响,更特别的是对酶活性有显著影响,当使用不同类型的酵母提取物时,酶产量变化高达50%。