Supplementation of Isomalto-oligosaccharide Reduced Colon Cancer-related Bacteria Enzymes and Fecal Toxicity in Nursing-home Residents

摘要

This study investigated effects of 2-month isomalto-oligosaccharide (IMO) supplementation on fecal colonic bacterial enzymes, bile acid metabolites, and fecal toxicity in the nursing-home residents. Twelve nursing-home residents (mean age 85.2 ± 1.9 y. o.) participated in the placebo-controlled and diet-controlled study. This experiment consisted of a 1-month placebo, 2-month IMO (10 g indigestible oligosaccharide/d) and 1 month post (IMO withdrawal) period. Stool samples were collected for analyses of glucuronidase, mucinase, bile acids and cytotoxicity. The fecal glucuronidase and mucinase activity was significantly lowered by 32% and 22%, respectively, with 1 month of IMO supplementation. The fecal glucuronidase and mucinase activity was furthermore reduced by 38% and 39% with 2-month supplementation. Two-month IMO supplementation significantly decreased the fecal deoxycholic acid, a secondary bile acid related to colon cancer incidence by 57% and. beneficially reduced the relative proportion of the secondary bile acid from 75.1% to 52.6%. Overall, one-month IMO supplementation was sufficient to decrease the cytotoxicity of fecal water with 3-h of co-incubation time. This human trial suggested that IMO (10 g/d) could effectively improve colonic ecology and reduce the colon cancer risk markers.