Effective Dose of Lactosucrose on Fecal Flora and Fecal Metabolites of Humans

Lactosucrose (4G-B-D-galactosylsucrose) was fermented in vitro by bifidobacteria and lactobacilli, and to a limited degree by the Bacteroides fragilis group, clostridia, eubacteria, and enterobacteriaceae. The effects of dietary lactosucrose on the fecal flora and fecal metabolites were studied in eight healthy volunteers (20-23 years of age) who ingested 3 g of lactosucrose/day for 7 days followed by 6 g of lactosucrose/day for 7 consecutive days. During lactosucrose intake, the counts of bifidobacteria were increased significantly (p< 0.001), whereas the counts of clostridia, including Clostridium perfringens, and bacteroidaceae were decreased significantly (p<0.05) compared with the values before the intake. The total bacterial counts were decreased significantly (p< 0.05) on day 14 during the intake. The frequency of occurrence of lecithinase-negative clostridia was decreased significantly (p<0.05) when compared with the values before and after the intake. No detectable changes occurred in the counts of other organisms throughout the experimental periods. Fecal concentrations of ammonia, sulfide, phenol, ethylphenol, skatol and indole were decreased significantly (p< 0.05) during lactosucrose intake. Acetic acid and lactic acid were increased significantly (p< 0.05) during the intake. Fecal enzyme activity of B-glucuronidase was decreased significantly (p< 0.05) on day 14 of the intake. Serum very low density lipoprotein (VLDL) was increased significantly (p< 0.01) on day 14 during the intake. Mean fecal pH values decreased from 6.3 to 5.9, and mean water content increased 3.6% during the intake. Fecal weight was increased slightly during the intake. The results obtained showed that the effective dose of lactosucrose for all healthy adults is 3 g/day.