传统阳江豆豉发酵过程中米曲霉的筛选及发酵条件优化

Screening and Optimization of Fermentation Conditions of Aspergillus oryzae Isolated from Yangjiang Lobster Sauce

摘要:

对从广东阳江豆豉的曲醅中筛选的米曲霉菌株进行培养基和发酵条件优化，结果表明，该菌产酶最适培养基的组成为添加3%的酵母粉、1%的葡萄糖、3%的硝酸钠和0.50%的氯化钙于基础PDA培养基中。该菌株产酶最优发酵条件为温度30 ℃，pH值为7~8，250 mL三角瓶中装瓶量为120 mL。在此最优条件下进行生长曲线绘制，培养12 h时，开始出现白色菌落，到36 h时，白色菌丝体明显增多，蛋白酶活力也持续增大，菌株培养48 h时，黄绿色孢子开始产生，蛋白酶活力达到最大值，到60 h时，菌株增长明显减慢，产生大量孢子，颜色较深，蛋白酶活力开始下降。综合菌量和蛋白酶活力，培养48 h为最适发酵时间。

Abstract:

The optimization of medium and fermentation conditions of Aspergillus oryzae were studied, which isolated from Gguangdong yangjiang lobster sauce. The results showed that, the optimum medium contained 3% yeast powder, 1% glucose, 3% sodium nitrate and 0.50% calcium chloride in PDA. The optimal fermentation conditions was temperature 30℃ and pH value 7~8. After cultivated 12 h, the medium was appeared white colony. At 36 h, white mycelium noticeably increased, protease activity also continued to increase. After 48 h, yellow-green spores were produced, protease vitality at maximize level, and at 60 h, strain growth slowed significantly, creating a large number of spore, and protease activity began to decline. So 48 h was the optimum fermentation time.