植酸酶产生菌的快速筛选及发酵条件优化

Rapid screening of phytase-producing strains and the optimization of fermentation conditions

采用改良的含溴甲酚绿的植酸钙平板初筛法,在极大提高植酸钙水解圈观察效果的同时,快速有效地初筛得到植酸酶产生菌。利用改进的钒钼酸铵法对发酵上清液进行酶活测定,在提高测定结果稳定性与可靠性的同时,复筛得到一株植酸酶高产菌株PHYf。对其发酵条件进行正交优化后,PHYf产植酸酶活力高达19.5U/mL。

The strains producing phytase were efficiently and effectively screened from the soil by primary screening medium containing phytate-calcium combined with bromocresol green which made the hydrolyzing circle more visible. At the secondary screening stage, the improved vanadium ammonium molybdate method with better stability and reliability was employed for phytase activity assay, and a strain with higher phytase production was marked as PHYf. By orthogonal experiment, the fermentation conditions were optimized and the phytase activity could reach 19.5 U/ml.