发光杆菌产几丁质酶的工艺优化

为提高海洋发光杆菌Photobacterium sp.LG-1产低温几丁质酶的酶活性，利用响应面法对其发酵产酶条件进行了优化。Plackett-Burman实验结果表明，影响菌株产酶的三个主要因素分别为发酵温度、发酵时间和酵母膏含量。菌株产酶的最适条件为:胶体几丁质浓度12.0 g/L、酵母膏浓度4.5 g/L、转速220 r/min、发酵温度20℃、装液量75 mL/250 mL、接种量1%、初始pH7.0、发酵时间120 h，几丁质酶的最大酶活为5.10 U/mL。实际平均酶活经验证与预测酶活相近，几丁质酶活比优化前提高了11.50%。为下一步低温几丁质酶的降解机制研究及在工业中的应用提供参考。

Optimization of Chitinase Production by the Photobacterium sp.LG-1

To increase chitinase activity,response surface methodology was used to optimize the fermentation conditions of cold-adapted chitinase by Photobacterium sp. LG-1. The result of Plackett-Burman showed that the important factors influencing chitinase production were fermentation temperature,fermentation time and yeast extract. The optimal fermentation conditions were determined as followed: colloidal chitin 12.0 g/L,yeast extract 4.5 g/L,shaking speed 220 r/min,fermentation temperature 20 ℃,liquid volume 75 mL/250 mL,inoculums dose 1%,pH7.0,and fermentation time 120 h,respectively. Under these conditions,the max enzyme activity of chitinase was 5.10 U/mL.The maximum theoretic value was consistent with mean value of verification test and the chitinase production was increased by 11.50% comparing to that before optimization.It provides a reference for the research on the degradation mechanism of low-temperature chitinase and its application in industry.