黄酒用脲酶产生菌的分离与选育

Isolation and screen of urease-producing bacteria used in rice-wine.

从２２批土样中分离到２７０余株能以尿素为唯一氮源的细菌，经变色圈法初筛，摇瓶复筛，获得产眠酶水平较高的菌株９０４３，初步鉴定为肠杆菌属菌（Ｅｎｔｅｒｏｂａｃｔｅｒｓｐ．）．采用紫外线和亚硝基胍进行诱变育种，得到产酶水平为０．３４Ｕ／ｍｌ的脲酶产生菌株９０４３Ｃ１２．模拟黄酒中应用试验表明，该菌所产豚酶在２５℃，ｐＨ５．０条件下，只需向含乙醇２０％（ｖ／ｖ）和尿素３０ｍｇ／Ｌ的模拟酒中添加６．０Ｕ／Ｌ就可在３６ｈ内使尿素的去除率达９０％以上．

Using the methods of color-changing circle and the screen shaking flask,a strain 9043 with relatively high yield of urease was abtained from 270 strains which were isolated from 22 soil samples. It was identified as the strain of Enterobacter sp.mutant strain 9043 C12 which could pro-duce 0.34 U/ml urease was selected from the strains being treated with UV and NTL. The analog rice-wine test proved that using this kind of urease at a level of 6.0U/L for 36h,25℃,pH 5.0,20%(v/v) alcohol and 30 mg/l, urea decomposition rate attained over 90%.