Sweet Potato Improves Defecation and Gut Microbiota of Female University Students

Abstract

Introduction: Effect of sweet potato, Benitenshi, on defecation and gut microbiota was examined in 22 female university students. Method(s): Dietary fiber was 2.9g (1.2g water soluble +1.7g insoluble) per 100g of Benitenshi peeled after heat treatment. The study consisted of 4 experimental periods and lasted 4 weeks. First week was control period, 2nd week was 300g intake of Benitensih period, 3rd week was 0g intake, and 4th week was 100g intake. Fecal weight was presumed on the basis of wood cube. Feeling of bowel condition and abdominal distention were obtained by 4 score questionnaire. Fresh fecal sample was collected to measure microflora on the last day of each experimental period. Result(s): Fecal weight was 1.6 times higher in 300g intake of Benitenshi (109.3g/day) and 1.5 times higher in 100g intake (109.3g/day) than control (66.4g/day). Dairy defecation number also significantly increased in 300g and 100g intake than control. Bowel condition and ease of defecation improved by 300g intake, and abdominal distention did not change. Gut microbiota was determined by 16S rRNA gene library, As a result, Bentenshi intake significantly increased a certain operational taxonomic units (OTU), A58, which contained Faecalibacterium sp. This species is known as excretion butyrate fatty acid. Conclusions, discussion and/or practical application: These findings suggest that Benitenshi intake might improve bowel condition and gut microbiota without abdominal distention. COMPETING INTERESTS: The authors of this document can confirm there is no conflict of interests.