粗壮假丝酵母(Candida valida 20231)产脂肪酶发酵条件的研究

Studies on fermentation conditions for lipase production by Candida valida 20231

对粗壮假丝酵母(Candida valida 20231)产脂肪酶所需的培养基成分和发酵条件进行了优化。结果表明,粗壮假丝酵母在接种后3 h即进入对数期,18 h后转入稳定期,66 h后进入衰退期;发酵36 h达到最大酶活,至72 h仍然无明显下降趋势。最适合的培养基成分为:4.0%大豆粉,2.0%菜籽油,0.3%葡萄糖,0.3%NH_4NO_3,1.2%K_2HPO_4,0.42%NaH_2PO_4,0.4%MgSO_4·7H_2O。使用优化的培养基,最佳产酶的条件为:装液量80 mL(250 mL摇瓶),初始pH 6,接种量为2.0%,种子菌龄为12 h。在最佳产酶条件下,脂肪酶活力达到32.6 U/mL。

The optimization of medium components and fermentation conditions for lipase production by Candida vallida 20231 was investigated. The results showed that during fermentation period Candida valida entered logarithmic phase after 3 h, transferred to stationary phase after 18 h, and then cane into decline phase after 66 h. The lipase activity reached the maximum at 36 h after fermentation, and the obvious descending trend could not be observed even at 72 h. The optimum medium compositions were as follows： 4.0% soybean flour, 2.0% rapeseed oil, 0.3 % glucose, 0.3% NH4 NO3, 1.2 % K2 HPO4, 0.42 % NaH2 PO4, 0.4 % MgSO4 7H2O. The optimum conditions for lipase production using optimized medium were： liquid volume 80 mL in 250 mL shaking flask, the original pH value 6, the inoculation volume 2% and the seed cell age 12 h. Under the optimized conditions, the maximum lipase activity reached 32.6 U/mL.