嗜热侧孢霉液体发酵产聚半乳糖醛酸酶条件优化

Optimization of Culture Medium and Liquid-state Fermentation Conditions for Polygalacturonase Production by Thermophilic sporotrichum

对嗜热侧孢霉(Thermophilic sporotrichum)液体发酵产聚半乳糖醛酸酶条件进行研究。得出最佳产酶培养基条件为:麸皮1.5%、(NH4)2SO4 0.5%、苹果皮粉3%、KH2PO4 0.1%、MgSO4.7H2O 0.025%,pH6.0;发酵条件为:装液量45mL/250mL三角瓶,培养温度50℃,转速170r/min,培养时间96h。最佳条件下培养,酶比活力为2768.97U/mL。

Thermophilic sporotrichum was cultured in a liquid medium with shaking for polygalacturonase production in this study.To improve polygalacturonase production,the culture medium composition and four fermentation conditions were optimized.The optimal culture medium composition found was composed of wheat bran 1.5%,（NH4）2SO4 0.5%,apple peel powder 3%,KH2PO4 0.1% and MgSO4·7H2O 0.025%,pH 6.0.The optimal values of the volume of the medium in a 250 mL conical flask,fermentation temperature and duration and shaking speed were determined to be 45 mL,50 ℃,96 h and 170 r/min,respectively.The fermentation broth obtained under the optimized conditions presented a polygalacturonase activity of 2768.97 U/mL.