新疆回民自制酸泡菜中产转糖基活性β-半乳糖苷酶菌株的筛选和鉴定

Screening and Identification of Strains Producing β-galactosidase with Transgalactosylation Activity from the Pickles of Hui in Xinjiang

[目的]通过可培养的方式从泡菜中分离和筛选产转糖基活性β-半乳糖苷酶(β-gal)的菌株。[方法]以乳糖为唯一碳源,Ca CO3溶钙圈和添加X-Gal的MRS筛选平板进行初筛,再通过o NPG法测定菌株β-gal活性进行复筛,最后以粗酶液催化乳糖进行转糖基反应,通过TLC分析确认转糖基活性。[结果]通过3级筛选,得到具有转糖基活性β-gal的菌株6株。结合其形态学、生理生化特征及16S r DNA序列同源性分析,确定筛选获得产转糖基活性β-gal菌株中,5株为发酵乳杆菌(Lactobacillus fermentum),1株为植物乳杆菌(Lactobacillus plantarum)。[结论]该研究可为以乳糖为底物高效合成功能性的低聚半乳糖提供新的酶源。

[ Objective]To isolate and screen the strains producing transglycosylated active p-galactosidase（ p-gal） from pickles by culturablmethods. [ Method] With lactose as the only carbon sourcc,CaCO3 calcium solution and X - G a l Mactivity of strain p-gal was rescreened by oNPG method. Finally, the glycosyl reaction was catalyzed bty of glycosyl group was confirmed by TLC analysis. [ Result] A total of 6 strains of transglycosyl activated p-gal were obtained by three stagscreening. According to its morphological,physiological and biochemical characteristics and the homolog analysis of 16S rDNA sequence,strains of Lactobacillus fermentum and 1 strain of Lactobacillus plantarurn were selected and obtained. [enzyme source for the efficient synthesis of functional Galacto oligosaccharides based on lactose.