Öner Özer, Aslim Belma, Aydaş Selcen Babaoğlu
Gazi University Faculty of Science, Department of Biology, Biotechnology Laboratory, Ankara, Turkey.
J Mol Microbiol Biotechnol. 2014;24(1):12-8. doi: 10.1159/000354316. Epub 2013 Oct 18.
The bile salt hydrolase (BSH) enzyme activities of human-derived lactic acid bacteria and bifidobacteria were evaluated. The highest enzyme activity was identified as 1.76 ± 0.23 U/mg protein for Bifidobacterium breve A26 and 1.42 ± 0.11 U/mg protein for Lactobacillus plantarum LA3. The bile salt deconjugation ability of the 6 isolates representing the highest BSH enzyme activity was calculated as the release of cholic acid and was between the range of 2.03 ± 0.22 and 1.05 ± 0.25 mM. The strains with high BSH enzyme activity also showed high deconjugation ability (p < 0.01). The effect of increasing bile concentrations on the growth of bacteria and their cholesterol removal abilities based on cholesterol precipitation were determined. Cholesterol removal in control medium was between 22.6 ± 0.4 and 26.5 ± 0.4%. The highest value was recorded at a 0.2% bile concentration. As the biliary concentration increased, a decrease in cholesterol removal and viability of the bacteria was noted in all strains. The percent of similarity of the bsh gene region between different genes was specified. The results may throw some light on proving the ability of these probiotics either as a novel alternative or as adjuvants to chemical drugs in treating hypercholesterolemia.
对源自人类的乳酸菌和双歧杆菌的胆汁盐水解酶（BSH）活性进行了评估。短双歧杆菌A26的最高酶活性被确定为1.76±0.23 U/mg蛋白质，植物乳杆菌LA3的最高酶活性为1.42±0.11 U/mg蛋白质。计算了代表最高BSH酶活性的6株分离株的胆汁盐去结合能力，以胆酸的释放量表示，其范围在2.03±0.22至1.05±0.25 mM之间。具有高BSH酶活性的菌株也表现出高去结合能力（p<0.01）。测定了胆汁浓度增加对细菌生长及其基于胆固醇沉淀的胆固醇去除能力的影响。对照培养基中的胆固醇去除率在22.6±0.4%至26.5±0.4%之间。在胆汁浓度为0.2%时记录到最高值。随着胆汁浓度的增加，所有菌株的胆固醇去除率和细菌活力均下降。确定了不同基因之间bsh基因区域的相似百分比。这些结果可能有助于证明这些益生菌作为治疗高胆固醇血症的新型替代物或化学药物佐剂的能力。
