棒曲霉Asp-195v产蛋白酶条件的优化

目的]优化高产蛋白酶棒曲霉Asp-195v的发酵条件。方法]利用正交设计方法研究培养基成分配比、含水量、初始pH值、培养时间、接种量和培养温度等发酵条件对棒曲霉Asp-195v产蛋白酶的影响。结果]影响该菌株产酶的最主要因素是培养时间,其次是温度,其他4个因素对该菌株产酶影响较小。该菌株最适产酶条件为：培养基成分中麸皮和豆粕比例为7∶3（总量为10g）,含水量为90ml（250ml三角瓶）,pH值为7,培养时间为72h,接种量为1.5ml,培养温度为24℃,摇床转数为120r/min。棒曲霉Asp-195v对盐有一定耐受力,其中24%NaCl中的蛋白酶与空白样品相比仍有47.6%的活性。结论]该菌株在豆酱生产中具有良好的应用价值。

The Optimal Liquid Fermentation Conditions for Protease Production by Asp-195v

Objective]The aim was to optimize fermentation conditions for protease production by Asp-195v.Method]The liquid fermentation conditions for protease production of the strain Asp-195v of Aspergillus clavatus were studied by orthogonal design method,which included medium constituent,water content,initial pH value,inoculum amount,fermentation time and temperature in 250 ml shaking bottle. Results]The results showed that the main factor affecting protease production was fermentation time. The optimal liquid fermentation conditions in shaking bottles were as follows: the ration of bran and bean cake was 7∶3(10 grams of total),water 90 ml,initial pH 7,inoculum amount was 1.5 ml,fermentation time was 72 h,fermentation temperature was 24 ℃,rotation speed was 120 r/min. The strain Asp-195 was able to produce protease in different salinity conditions,which had a certain degree of tolerance to salt,its protease activity in 24%NaCl was 47.6% compared to the blank test without NaCl.Conclusion] The strain had a good application value in the miso production.