紫外线诱变选育高产柠檬酸菌株及发酵条件研究

对1株初筛产柠檬酸黑曲霉进行紫外线诱变处理，并对选育的优势菌进行了发酵条件实验。研究结果表明，选育出的（Aspergillus niger）UV-5是一株优良高产菌株，该菌株的产酸率达到11.54%，比初始菌株（YZ-35）产酸率提高了24.41%；以红薯为发酵原料，在初始糖浓度15%、温度为35℃、起始pH值为5.5，转速140r·min-1、发酵84h的优化条件下，摇瓶发酵平均产酸率可达到13.15%。

Mutagenic Breeding of Producing Citric Acid Aspergillus Niger Strains

Screening for a production of citric acid by Aspergillus niger UV mutagenic treatment, and dominant bacteria breeding experiments carried out fermentation conditions. The results showed that breeding （Aspergillus niger） UV-5 was an excellent high-yielding strains of strain, the strain of acid production rate reached 11.54%. Compared with the initial strain （YZ-35）, acid production rate increased by 24.41%;sweet potato as fermentation of raw materials, 15%of the initial sugar concentration, the temperature was 35℃, initial pH 5.5, speed 140r/min. Under optimal conditions 84h of fermentation, fermentation acid production rate reached an average of 13.15%.