曲酸生产菌种的筛选和发酵培养条件的优化

Selection of Kojic Acid Producing Strains and optimization of the Fermentation Condition

通过多次UV诱变黄曲霉菌A－5，获得-高产曲酸生产菌株UV3x3，该菌株的适宜发酵条件为：温度33℃，淀粉14％，酵母浸出物0．5％，H3PO4。0．07％，MgSO4·7H2O0．05％，FeSO4·7H2O0．002％，K2CO30.03％，在此条件下摇瓶培养6天可生产曲酸6．84g／100m，平均生产效率为11．4g／（1·d），后期生产效率达15．4g／（1·d），转化率为55％。

A high kojic acid producing mutant UV3x3 was screened out from an Aspergillus flavus strain A-5 using UV mutation technique. The strain produced 6. 84g/100mlkojic acid in 6 days under an optimal shaking flask cultivation condition:temperature, 33 ℃;corn starch, 14%; yeast extract, 0. 5%; H3PO4, 0.07%; MgSO4· 7H2O, 0. 05%; FeSO4.7H2O, 0. 002 %; K2CO3, 0. 03 %. The overall productivity was 11. 4g/ (1. d ) and 15. 4g/ (1. d )was reached in the later period, with conversion yield of 55% on the reducing sugar con-sumed.