几株植物乳杆菌β-葡萄糖苷酶的特性研究

Characteristics of β-glucosidase from Lactobacillus plantarum

通过比色法测定酶活,比较5株植物乳杆菌(Lactobacillus plantarum)产β-葡萄糖苷酶的特性,对胞内β-葡萄糖苷酶最佳反应pH和温度进行了研究,考察了氯化钠及乙醇对β-葡萄糖苷酶活性的影响。结果表明,5株植物乳杆菌都可以产生胞内β-葡萄糖苷酶,其中比酶活最高的为菌株W-4(14.168 U/g),其次是菌株Y-12(13.015 U/g),之后分别是菌株Y-20(11.359 U/g)、菌株1.3919(7.029 U/g)及菌株Y-22(4.630 U/g);植物乳杆菌W-4和1.3919还可以产生胞外酶;菌株W-4的胞内β-葡萄糖苷酶的最适反应pH为4.0～4.5,菌株Y-12的最适pH为4.5,菌株Y-20和1.3919的最适pH为5.5,菌株Y-22的最适pH为5.0;菌株W-4、Y-20、Y-22及1.3919的最适反应温度均为30℃,而菌株Y-12的最适反应温度为37℃。不同含量的氯化钠和乙醇对5株植物乳杆菌的β-葡萄糖苷酶活性具有一定的抑制作用,且浓度与抑制作用呈正相关。

The characteristics ofβ-glycosidase produced by 5 strains of Lactobacillus plantarum were compared by colorimetric method.The optimum reaction temperature and pH of intracellularβ-glycosidase were studied,and the effects of sodium chloride and ethanol onβ-glycosidase activity were also investigated.The results showed that all strains could produce intracellularβ-glycosidase,among them,the strain W-4 had the highest enzyme activity(14.168 U/g),followed by Y-12(13.015 U/g),Y-20(11.359 U/g),1.3919(7.029 U/g)and Y-22(4.630 U/g),and the strain W-4 and 1.3919 could also produce extracellularβ-glycosidase.The optimum reaction pH of intracellularβ-glycosidase produced by strain W-4,Y-12,Y-20,1.3919 and Y-22 were 4.0-4.5,4.5,5.5,5.5 and 5.0,respectively.The optimum reaction temperature of strain W-4,Y-20,Y-22 and 1.3919 were all 30℃,while the optimum reaction temperature of strain Y-12 was 37℃.Different concentrations of sodium chloride and ethanol had a certain inhibitory effect on the activity ofβ-glucosidase produced by 5 strains of L.plantarum,which had a positive correlation with inhibitory effect.