Abstract
Effects of a daily intake of soft drink containing 4g of galacto-oligosaccharides(GOS) on defecation frequency, fecal properties and fecal microflora were evaluated by a double-blind crossover study in 51 healthy female students (average age 19.7±1.2 y). The subjects were divided into two groups and given a 60 mL/day (containing 4 g GOS) of soft drink or a placebo drink for three weeks each with two weeks interval. Seventeen subjects of them, whose viable Bifidobacterium counts in feces were less than 30% of the total fecal bacterial counts, were analyzed for their fecal microflora before and after the both drinks intake period. As a result, after the GOS drink intake, in 28 subjects whose defecation was less than five days per week, significant increases in defecation frequency and fecal volume were observed compared to the placebo drink intake (p<0.05) or the non-intake period (p<0.01). Fecal microfloral analysis revealed the number of total anaerobic bacteria and Bifidobacteria to have increased significantly compared to the placebo drink intake (p<0.05) or the non-intake period (p<0.05, p<0.01, respectively), and the occupation percentage of Bifidobacteria in the total count of fecal microflora was tended to increase compared to the placebo drink intake or significantly increased compared to the non-intake period (p<0.05). On the other hand, the number of Clostridium lecithinase (+) significantly decreased compared to the non-intake period (p<0.05). Furthermore, in 6 subjects, whose viable Bifidobacterium counts in feces were less than 10% of the total fecal bacterial counts before the GOS drink intake period, the number of Bifidobacteria and Lactobacilli increased significantly, and the occupation percentage of Bifidobacteria in the total count of fecal microflora was significantly increased compared to the non-intake period (p<0.05, respectively). These results clearly show that the daily intake of the soft drink containing 4g GOS per 60m1 contributes to improve defecation and fecal properties through its prebiotic effects on increasing useful intestinal bacteria and simultaneous decreasing harmful intestinal bacteria to keep a good intestinal environment.
