响应面法优化黑曲霉产抗菌物质的发酵培养基

Optimization of fermentation medium for antibacterial material produced by Aspergillus niger with response surface methodology

以抑菌圈直径为响应值,采用响应面法对黑曲霉（Aspergillus niger）xj产抗菌物质的发酵培养基进行优化.首先通过单因素试验确定最适碳源和氮源分别为麦芽糖和麦麸,并初步考察了麦芽糖、麦麸、无机盐、生长因子及表面活性剂的最适添加量.通过Plackett-Burman设计筛选出影响抗菌物质活力的显著因素：无水硫酸镁、氯化钙和吐温-80.最后通过中心复合设计及响应面分析确定产抗菌物质的的最优发酵培养基组分为麦芽糖30.00g/L、麦麸7.50g/L、酵母膏1.00g/L、磷酸氢二钾1.00g/L、无水硫酸镁0.2982g/L、吐温-80 0.24mL/L、微量元素液2.00mL/L、氯化钾0.50g/L.采用滤纸片扩散法检测优化后的发酵液抗菌活性,抑菌圈直径为（27.26±0.41）mm,比未经优化测得的抑菌圈直径提高了83％.

Taking inhibition zone diameter as the response value,single-factor tests and response surface methodology （RSM） were used to optimize fermentation conditions for antibacterial material produced by Aspergillus niger.Firstly,the optimum carbon source and nitrogen source were determined as maltose and wheat bran by single factor experiment.Secondly,the optimum addition of maltose,wheat bran,inorganic salt,growth factors and surfactant were determined.The significant factors affecting antibacterial material energy were MgSO4,CaC12 and Tween-80 selected by Plackett-Burman design.Finally,the optimized fermentation medium was obtained by central composite design and response surface analysis：maltose 30.00g/L,wheat bran 7.50g/L,yeast paste 1.00g/L,K2HPO4 1.00g/L,MgSO4 0.2982g/L,Tween-80 0.24ml/L,trace elements liquid 2.00ml/L and KCI 0.50g/L.Detecting the optimized fermented liquid antibacterial activity by filter paper diffusion method,it turned out that the diameter of inhibitory zone reached （27.26±0.4 1）mm,which was 83％ higher compared with the one before optimization （the liquid PDA fermentation medium）.