黑曲霉产植酸酶发酵工艺优化

Optimization of Fermentation for Phytase Production of Aspergillus niger

对黑曲霉液态发酵产酸性植酸酶的发酵工艺进行了优化实验。通过正交试验进行培养基优化得到最佳配比为:5%可溶性淀粉,5%豆粕,0.9%KCl,0.1%FeSO4·7H2O,0.9%MgSO4·7H2O,0.5%MnSO4。根据极差可知,影响程度,MgSO4·7H2O>可溶性淀粉>豆粕>MnSO4>FeSO4·7H2O>KCl。通过对发酵条件进行单因素优化得到黑曲霉发酵产植酸酶的最佳发酵条件是:发酵温度30℃,初始pH5.5,摇床转速220r/min,发酵时间60h。在优化条件下,酸性植酸酶酶活力达到了20U。

The optimization of fermentation process for the production of acidic phytase by Aspergillus niger was carried out. Fermentation medium was optimized through orthogonal array design and the optimal medium consisted of 5%soluble starch, 5%bean pulp, 0.9%KCl, 0.1%FeSO4·7H2O, 0.9%MgSO4·7H2O, 0.5%MnSO4. The effect of the factor on the yield of phytase decreased in the following order：MgSO4·7H2O, soluble starch, bean pulp, MnSO4, FeSO4·7H2O, KCl. Base on the single factor experiment, the optimal fermentation condition was fermentation temperature 30 ℃, the initial pH 5.5, the shaking speed 220 r/min and the fermentation time 60 h . In the optimized conditions, the acidic phytase enzyme activity reached 20 U.