一株源于北派酱香白酒酿造环境中产淀粉酶细菌的筛选、鉴定及其特性研究

采用平板涂布法从酱香型白酒酿造环境（大曲、酒醅和窖泥）筛选产淀粉酶细菌菌株，通过菌落形态、细胞显微结构、生理生化特性和分子生物学方法对其进行鉴定，并对其生长特性及耐受性进行研究。结果表明，从酱香型白酒大曲中筛选得到一株产淀粉酶的细菌，编号为2-2，经鉴定菌株2-2为解淀粉芽孢杆菌（Bacillus amyloliquefaciens）。菌株2-2能够在25～45 ℃和pH 5～9范围内生长良好，属于乙醇高耐受性菌株，在乙醇体积分数为12%时仍能生长，并具有较高的NaCl和葡萄糖耐受性，最高耐受质量分数分别为15%和70%。菌株2-2在高粱酶解液中能产生酱香型白酒中的多种重要风味物质，如苯乙醇、糠醇3-羟基-2-丁酮、2,5-二甲基吡嗪和乙烯基愈创木酚等，是酱香型白酒酿造中重要的功能菌株。

Isolation and identification of an amylase-producing bacterium from Beipai sauce-flavor Baijiu brewing environment and its characteristics research

Amylase-producing bacteria were screening from sauce-flavor Baijiu (Chinese liquor) brewing environment (Daqu, fermented grains and pit mud) by spread plate method. The strains were identified by colony morphology, cell microstructure, physiological and biochemical characteristics and molecular biological methods, their growth characteristics and tolerance were studied. The results showed that a strain of amylase-producing bacterium was screened from sauce-flavor Baijiu Daqu, numbered 2-2. The strain 2-2 was identified as Bacillus amyloliquefaciens. The strain 2-2 could grow well in the range of 25-45 ℃ and pH 5-9. The strain belonged to high ethanol tolerance strain, and could still grow when the ethanol volume fraction was 12%. It had high tolerance to NaCl and glucose, with the highest tolerance mass fraction of 15% and 70%, respectively. The strain 2-2 could produce a variety of important flavor substances of sauce-flavor Baijiu in the sorghum enzymatic hydrolysate, such as phenethyl alcohol, furfuryl alcohol 3-hydroxy-2-butanone, 2,5-dimethylpyrazine and vinylguaiacol, etc., which was an important functional strain in sauce-flavor Baijiu brewing.