产植酸酶菌株的筛选及其产酶条件研究

Screening of phytase producing strain and optimization of fermentation conditions

摘要: 本研究筛选出1株稳定的产植酸酶菌株，初步鉴定为黑曲霉，命名为Aspergullus niger FZ41。摸索了液体发酵产酶的最佳条件，获得其最适发酵培养基（w/w）：可溶性淀粉4%，NH₄NO₃ 0.08%，KCl 0.05%，MgSO₄·7H₂O 0.05%，FeSO₄·7H₂O 0.003%，MnSO₄·7H₂O 0.003%，水1 L。培养基起始pH值6.0，种龄为36 h，接种量为5%，装液量为50/500 mL，在30 ℃、220 r·min^{-1^{下培养84 h，酶活可达219 U·mL^-1。}}

Abstract: A phytase-producing strain was isolated and identified as Aspergullus niger FZ41. Liquid fermentation was investigated and the optimal fermentation medium obtained. A 500 mL flask filled with 50 mL inoculums with an initial pH of 6.0 was used in the inoculation. The relative percents of ingredients of fermentation medium were: starch 4%, NH₄NO₃ 0.08%, KCl 0.05%, MgSO₄·7H₂ 0.05%, FeSO₄·7H₂ 0.003%, MnSO₄·7H₂ 0.003%. The age of the inoculums was 36 h, with initial medium pH 6.0 and an inoculation dose of 5%. Extracellular phytase production was 219 U·mL^{-1^{under fermentation conditions of 30 ℃ at 220 r·min^{-1^{for 84 h.}}}}