微孢根霉产凝乳酶的发酵条件优化

Optimization of fermentation conditions for milk clotting enzyme production by Rhizopus microsporus

筛选得到一株高产凝乳酶的菌株F518,鉴定为微孢根霉。通过单因素试验优化了微孢根霉F518液体发酵产凝乳酶的发酵条件。结果表明:发酵产酶的最适碳源为酒糟,最适氮源为酵母浸粉,培养基最适初始pH为5.0。在优化后的发酵条件下30℃培养72h,微孢根霉F518产凝乳酶活性最高,达到1 001SU/mL。微孢根霉F518在凝乳酶生产方面有很大的应用前景。

The strain F518,identified as Rhizopus microsporus,was newly isolated from fermented bean curd for its high level of milk clotting enzyme production.The single-factor tests were employed to evaluate the optimal fermentation conditions for milk clotting enzyme production of RhizopusmicrosporusF518by liquid fermentation.The results showed that the optimal conditions for milk clotting enzyme production were as follows:vinasse as carbon source,yeast extract as nitrogen source,the initial pH was 5.0and incubation temperature was 30℃.Under optimized conditions,the highest enzyme activity of 1 001SU/mL was obtained after 72hof incubation.Rhizopus microsporus F518possesses a potential application from the industrial point of view for the milk clotting enzyme production.