Effect of Yacon Tuber (<i>Smallanthus sonchifolius</i>)-derived Fructooligosaccharides on the Intestinal Flora and Immune System of OVA-sensitized BALB/c Mice

Abstract

Yacon (Smallanthus sonchifolius) tuber contains fructooligosaccharides (FOS). FOS are known as prebiotics that beneficially affect the host, i.e., improve the intestinal flora balance and enhance the immunomodulatory potential. In this study, we investigated the effect of a yacon extract rich in FOS (YOS) on the intestinal flora and immune system of BALB/c mice sensitized and challenged with ovalbumin in comparison with an extract with acid-degraded FOS (YAH). During the 4-week test period, the amount of YOS intake was lower than that of YAH; however, a significant increase in body weight was not shown among any of the test groups. Sneezing events were observed in OVA-treated mice. It was found that administration of yacon FOS improved the intestinal flora. Further, it was suggested that administration of yacon-derived FOS could epidemiologically improve the Th1/Th2 cytokine balance through its prebiotic effect on the number of beneficial bacteria in the animal gut.