Comparison of functions on intestinal microbes between strains of Bifidobacterium and Ruminococcus.

不易消化的益生菌对控制结肠中的微生物群很重要。低聚果糖（FOS）是一种典型的难消化性低聚糖，对双歧杆菌有促进作用。利用微生物酶高效制备难消化低聚糖DFAIII（二果糖酐III）。DFAIII能促进从人粪便中分离的Ruminococcus productus AHU 1760的生长，但不能促进双歧杆菌的生长，因为双歧杆菌不能降解DFAIII。在这项研究中，我们比较了DFAIII + Ruminococcus productus AHU 1760与FOS +短双歧杆菌JCM 1192 T的健康效果。这两种组合是共生的。以富含FOS的天然蔬菜雪莲果为试验材料，与FOS试剂进行对比。所用大鼠为5周龄SD雄性，采用普通饲料和高脂饲料。饲养30 d后，采用高效液相色谱法（HPLC）、DNA PCR-DGGE技术分析盲肠内容物pH、有机酸组成、微生物菌群，结果表明，两种共生菌均表现出盲肠内容物和粪便pH明显下降，说明肠道内微生物大量生长，肠道发酵作用明显。在高脂肪条件下观察到差异。DFAIII与Ruminococcus productus AHU 1760的共生菌能维持较低的肠道pH，而FOS与短双歧杆菌JCM 1192 T的共生菌不能维持较低的肠道pH。这些结果支持DNA PCR-DGGE分析。产瘤胃球菌AHU 1760的保健效果优于短双歧杆菌JCM 1192 T。雪莲果死亡后肠道菌群和pH值变化快，比FOS试剂具有更好的保健效果。

In-digestible saccharides are important to control microbiota in colon. Fructo-oligosaccharide (FOS) is a typical in-digestible oligosaccharide, and it increase cells of Bifidobacterium species. We made process to make different in-digestible oligosaccharide which is DFAIII (di-fructose anhydride III) with using microbial enzyme effectively. DFAIII enhanced growth of Ruminococcus productus AHU1760 which was isolated from human feces, but not growth of Bifidobacterium strains because Bifidobacterium strains can’t degrade DFAIII. In this study we compared health effect of DFAIII + Ruminococcus productus AHU1760 vs. FOS + Bifidobacterium breve JCM1192T. Both combination were symbiotic. Yacon which is FOS rich natural vegetable were used as comparison with reagent FOS. Rat used were SD male 5 weeks with normal feed and high fat feed were used. Rats were kept for 30 days and analyzed pH, organic acid compositions, microbiota in cecum with using HPLC, DNA PCR-DGGE.Both symbiotic showed clear pH decrease in cecal contents and feces which indicated abundant intestinal fermentation by abundant growth of microbes. Differences were observed in high fat conditions. Symbiotic by DFAIII and Ruminococcus productus AHU1760 continued abundant intestinal fermentations and kept intestinal pH in lower condition but not symbiotic by FOS and Bifidobacterium breve JCM1192T. Those results were supported DNA PCR-DGGE analysis. Ruminococcus productus AHU1760 showed better health effect than Bifidobacterium breve JCM1192T. Yacon died gave faster change of intestinal microbiota and pH which shoeing better health effect than reagent FOS.