Abstract
Abstract The effect of lactitol on intestinal bacteria was compared with that of lactulose in vitro and in vivo. The utilization of lactitol and lactulose by human intestinal bacteria (11 genera, 35 species, 48 strains) in vitro was tested by measuring the pH of the medium after a 48-hr incubation. Lactitol was utilized by 15 strains, and lactulose by 37 strains. That is, lactitol was utilized by fewer species of Bifidobacterium, Lactobacillus, Bacteroides and Clostridium than lactulose was. The cecal microbial flora was examined in rats treated orally with lactitol or lactulose for 7.5 days. The changes in the cecal flora caused by lactitol were almost the same as those caused by lactulose at the medium and high doses. The increases in the numbers of bifidobacteria were particularly noticeable Enterobacteriaceae, Streptococcus and bacteroidaceae also increased at the high dose of both drugs.
