发酵生产β-环状糊精葡萄糖基转移酶的气球菌(Aerococcus sp·P3-2)污染及防治

摘要

An Aerococcus strain was isolated from the aberrant fermentation broth β - cyclodextrin glucosyltransferase by using phenolphthalein culture medium. This strain can grow in alkaline medium for β - cyclodextrin glucosyltransferase fermentation, but could not produce the enzyme. The bacteria OD, pH, enzyme activity, and 16SrDNA gene sequence were analyzed. The strain was identified as Aerococcus sp. P3 - 2, which could lower pH of fermentation broth for preventing normal bacteria growth. We used conventional microorganism sampling analysis to find out that the aerococcus may be grow in fermentation process. The cause of fermentation pollution was from air purification system. The waster in air purification system must be treated and PH value should be monitored to prevent the pollution.%我们从环状糊精生产厂家的β-环状糊精葡萄糖基转移酶发酵失败的发酵液中分离出一株气球菌.此菌可以在发酵专用碱性培养基上生长,但不生产β-环状糊精葡萄糖基转移酶.通过研究该菌种在碱性培养基上的发酵过程中的pH、OD、酶活,同时使用16SrDNA进行分析,证明此菌种为气球菌(Aerococcus sp.P3-2),其在发酵过程中可以明显降低发酵培养基的pH,对正常生产菌形成抑制.通过对发酵生产可能染菌的环节进行微生物取样分析,该菌种大量存在于空气过滤系统的积水中,从而找到污染源,由此判断是由于空气净化系统被污染所导致的发酵失败.在实际生产中定期对空气净化系统中的积水进行排放处理,同时对发酵过程中的酶活和pH进行监控,可以做到发酵污染的早发现直至杜绝发酵污染.