超高压对枯草杆菌胞外蛋白酶的影响

 以枯草杆菌为研究对象，采用Box-Behnken响应曲面设计，研究了超高压处理对枯草杆菌胞外蛋白酶的影响以及菌体致死与胞外酶的关系。结果表明，超高压能显著抑制枯草杆菌胞外蛋白酶的活性，处理过程中压力和温度是酶失活的主要因素，并且两者之间存在交互作用，超高压处理时温度协同有效。利用Design Expert软件建立了胞外蛋白酶超高压钝化模型，决定系数R₂=0.974 7，调整决定系数R_2,adj=0.942 1。方差分析表明，模型显著，可应用于钝化效果分析与预测。实验结果还表明，超高压处理后枯草杆菌的致死率与胞外蛋白酶活的变化相关性达到极显著水平（R=0.933 0），胞外酶可作为超高压处理对微生物影响的一个评价指标。

Effect of High Pressure on Exoproteinase of Bacillus subtilis

We studied the effect of high pressure process(HPP) on exoproteinase of Bacillus subtilis by using Box-Behnken response surface methodology.Experimental results showed that HPP could inhibit activity of exoproteinase significantly.In the course of treatment,pressure and temperature were key factors to passivate enzyme,and their interaction was notable.A model of exoproteinase passivation was established by design expert software,which determination coefficient was 0.974 7 and adjusted determination coefficient was 0.942 1.Analysis of variance implied that the model was significant.Therefore,the model could be used to analyze and predict.Additionally,the experiment indicated that exoproteinase activity correlated with lethal rate significantly(R=0.933 0).The exoproteinase could be regarded as an index to evaluate effect of HPP on microorganism.