^(60)Co-γ射线诱变柠檬酸产生菌黑曲霉Co9-6的研究

MUTAGENESIS OF CITRIC ACID PRODUCTING STRAINS OF ASPERGILLUS NIGER Co9-6 WITH ^(60) Co GAMMA RAYS

本试验采用￣（６０）Ｃｏ－γ射线对柠檬酸产生菌黑曲霉Ｃｏ９－６进行辐射，经两次处理后选育出Ｌ１２１７和Ｌ８０１两株优良柠檬酸产生菌。中试结果表明菌株Ｌ１２１７较Ｌ８０１更优：产酸率较菌株Ｃｏ９－６提高１７．６％、发酵周期缩短１３．４％、对糖转化率提高１３．３％。

In this experiment ￣(60)Co gamma rays were used to irradiate citric acid producingstrains of Aspergillus Niger Co9-6. Two fine citric acid producing strains,L801 andL1217,were obtained through twice treatment and selection. More than seven batches of fer-mentation tests on the scale of 50-ton or 100-ton fermenten were repeatedly conducted.Results indicated that the strain of L1217 was better than L801. The average yield of citricacid and the fermentation time as well as the comersation rate of glucose to citric acid respec-tively was 17.6%higher, 13.4%shorter and 13.3%higher than that of the Aspergillusniger Co9-6.