%0 Journal Article
%T Enterobacter agglomerans B1 producing β-galactosidase with transglycosylation activity: screening, identification, fermentation conditions, and galacto-oligosaccharides synthesis<br>转糖基β-半乳糖苷酶产生菌Enterobacter agglomerans B1：筛选鉴定、发酵产酶及其合成低聚半乳糖的研究
%A Lili Lu
%A Min Xiao
%A Xiaodong Xu
%A <br>卢丽丽
%A 肖敏
%A 徐晓东
%J 微生物学报
%D 2008
%I 
%X Galacto-oligosaccharides (GOS) are promising non-digestible oligosaccharides recognized as prebiotics. Commercial GOS containing galactose as subunit, are synthesized from lactose using the galactosyl-transferase activity of beta-galactosidase. A strain producing beta-galactosidase with transglycosylation activity was screened from the soil. Phenotypic analysis including morphology and physiology characteristics and 16S rDNA sequence analysis were carried out. Based on taxonomy results, the strain was identified as Enterobacter agglomerans B1. Medium and fermentation conditions were optimized by single factor and orthogonal experiments. The enzyme reached 9.7 U/mL in the medium (pH 7.5) containing 1% lactose, 1% yeast extract, and 0.5% peptone when cultured at 25 degrees C for 26 h. Effects of pH, temperature, lactose concentration, and reaction time on transgalactosylation by whole cells were studied. Yield of GOS reached 40.7% in 30% lactose (pH 7.5) at 50 degrees C for 12 h, as analyzed by HPLC and TLC. The results of an MS analysis showed that GOS were composed of di, tri-, and tetrasaccharides.
%K 成团肠杆菌
%K 鉴定
%K 转糖基β-半乳糖苷酶
%K 发酵条件
%K 低聚半乳糖
%K 糖基
%K 半乳糖苷酶
%K 产生菌
%K agglomerans
%K Enterobacter
%K 筛选鉴定
%K 发酵产酶
%K 合成
%K 低聚半乳糖
%K 技术研究
%K producing
%K activity
%K galactosidase
%K screening
%K identification
%K conditions
%K fermentation
%K 二糖
%K 转移
%K 组分
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A3C6BA55AB623B90FA9104CFFC826F3C&aid=E1E471BBE918D236A42F65E181CA6BF8&yid=67289AFF6305E306&vid=B6DA1AC076E37400&iid=CA4FD0336C81A37A&sid=16D8618C6164A3ED&eid=1AE5323881A5ECDC&journal_id=0001-6209&journal_name=微生物学报&referenced_num=0&reference_num=29