产黄曲霉毒素B_1降解酶菌株的发酵工艺优化

Optimization of Fermentation Technology for AFB_1-Degrading Enzyme Producing Strain

黄曲霉毒素主要是由黄曲霉和寄生曲霉等真菌在生长繁殖过程中产生的有毒次级代谢产物。其具有极强的毒性、致癌性和致突变性并且广泛存在于食品、饲料、农副产品中,对人类和动物产生了极大的危害。试验在前期研究的基础上通过Plackett-Burman试验设计和中心复合设计对HSD8(Sinomonas sp.)菌株的发酵培养基进行优化,最终确定其发酵培养基为:糖蜜3 g/L,柠檬酸氢二铵10 g/L,磷酸二氢钾2 g/L,三水合磷酸氢二钾0.4 g/L,氯化钠4.5 g/L,一水合硫酸镁0.6 g/L,氯化钙0.6 g/L,硫酸镁2.16 g/L,香豆素0.17 g/L。通过对模型验证试验,黄曲霉毒素B_1降解酶酶活达736 U/mL,比优化前提高了25.54%。试验对菌株HSD8在生物降解黄曲霉毒素B_1方面具有指导意义,值得进一步研究开发。

Af latoxins were typically found as toxic secondary metabolites produced by fungus like Aspergillus parasiticus and Aspergillus f lavus when they grew and propagated. Af latoxin was extremely toxic, mutagenic, carcinogenic and widely exists in the food, feed and agricultural and sideline products, posing great hazard to both humans and livestock. Through Plackett-Burman design and central composite design（CCD）, the fermentation medium was determined as follows： molasses 3 g/L, diammonium hydrogen citrate 10 g/L, monopotassium phosphate 2 g/L, trihydrate potassium hydrogen phosphate 0.4 g/L, sodium chloride 4.5 g/L, kieserite 0.6 g/L, calcium chloride 0.6 g/L, magnesium sulfate 2.16 g/L, coumarin 0.17 g/L. Further proven experiments to the model showed that the activity of AFB_1-degradation enzyme reached 736 U/mL which was 25.54% higher than that of pre-optimization. It had guiding signif icance for biological degradation of AFB_1 by the strain of HSD8 and valuable to further research and development.