Effect of Food Substances on beta-glucuronidase Activity of lntestinal Bacteria.

本研究采用电泳法和活性染色酶法研究了食物对肠道微生物区系β-葡萄糖醛酸苷酶代谢的影响。与上述方法相结合，分别建立了各产生菌的活性测定方法。将该方法应用于大鼠盲肠内容物和人粪便中。大鼠灌胃香料后，盲肠β-葡萄糖苷酶活性显著提高。在大鼠盲肠组织中，我们在PAGE凝胶上只检测到一条β-葡萄糖醛酸酶活性条带，该条带与大肠杆菌β-葡萄糖醛酸酶的活性条带一致。这是由于大肠杆菌中β-葡萄糖醛酸酶活性的提高所致。以酶带浓度为指标，检测盲肠总活力的变化。从大肠杆菌总数不变的实验结果来看，可以合理地得出结论，这种活性的增加依赖于大肠杆菌β-葡萄糖苷酶产量的增加。在健康人的粪便中，PAGE凝胶上检测到两条活性条带。其中1株与大肠杆菌β-葡萄糖苷酸酶测定结果基本一致，另1株矿工菌与脆弱类杆菌酶测定结果基本一致。在人类粪便中，β-葡萄糖醛酸苷酶的主要活性是大肠杆菌，本研究的问题是以6-溴-2-萘基-β-D-葡萄糖醛酸苷或α-萘酚-AS-β-葡萄糖醛酸苷为底物的低检出限染色酶法。因此，这种方法不足以检测低活性的同工酶。

This study was conducted to clarify the effect of food substances on beta-glucuronidase metabolism of intestinal microflora by using the electrophoresis and the activity staining enzyme method. By using together with above methods, the measuring assay for the activity of each producing bacteria, respectively was established. This method was applied to the rat cecal content and human fecesBy supplemented spices to rats, the activity of cecal beta-glucronidase activity was increased significantly. In tha rat cecum, we detected only one of beta-glucuronidase active band on the PAGE gel, and this band was in accord with that established in Esherichia coli beta-glucuronidase. This increase was resulted from activity increase of beta-glucuronidase of E.coli. Changes of total activity in cecum were detected as the enzyme band concentrations of E.coli. From the experimental results of the total number of E.coli did not varied, It may be reasonable to conclude that the increases of the activities depend on the increases of production rate of beta-glucronidase from E.coli.We detected two active bands on PAGE gel in healthy human feces. One was major in accord with that established in E.coli beta-glucuronidase, and another miner was in accord with Bacteroides fragilis enzyme. In human feces, major activity of beta-glucuronidase was E.coli orgin.The problem in this study is the low detectable limit activity staining enzyme method with the substrate as 6-brom-2 naphtyl-beta-D-glucuronide or alpha-naphtol-AS-Bl beta-glucuronide. Therefore, this method are inadequate to detect low activity of the isozyme.