为提高白酒酿造过程中阿魏酸的含量,该研究从浓香型白酒大曲中分离筛选产阿魏酸酯酶的菌株,通过形态观察、生理生化试验及分子生物学技术对其进行菌种鉴定,并以阿魏酸酯酶活力为评价指标,采用单因素试验及响应面试验对其发酵条件进行优化。结果表明,筛选得到一株产阿魏酸酯酶的菌株,编号为M2。经鉴定,其为一株蜡样芽孢杆菌(Bacillus cereus),该菌株产阿魏酸酯酶的最佳发酵条件为接种量5%,发酵温度30℃,初始pH值5.5,发酵时间72 h。在此优化条件下,阿魏酸酯酶活力为33.89 U/L,比优化前提高10.03%,具有较强的产阿魏酸酯酶能力。
In order to improve the content of ferulic acid in the brewing process of Baijiu, the ferulic acid esterase-producing strains were isolated and screened from strong-flavor (Nongxiangxing) Baijiu Daqu, and identified by morphological observation, physiological and biochemical tests and molecular biology techniques. Using ferulic acid esterase activity as evaluation index, the fermentation conditions were optimized by single factor experiments and response surface methodology. The results showed that a ferulic acid esterase-producing strain was obtained by screening, which was numbered as M2. It was identified as Bacillus cereus. The optimal fermentation conditions for the strain to produce ferulic acid esterase were inoculum 5%, fermentation temperature 30 ℃, initial pH 5.5, and time 72 h. Under the optimized conditions, the activity of ferulic acid esterase was 33.89 U/L, which was 10.03% higher than that before optimization, and it had a strong ability to produce ferulic acid esterase.