Abstract:The effect of acorn starch isomalto-oligosaccharide on the proliferation ofBifidobacteriumand its laxative effect was explored.Being used as carbon source substitute for glucose in MRS medium，the proliferation test and the comparison of growth curves were done；the constipation model group，blank control group，acorn starch isomalto-oligosaccharide low，medium，and high dose groups were established with mice，at the same time，the experiment of mice defecation and intestinal propulsion were done.Text results showed that the acorn starch isomalto-oligosaccharide had significant promoting effects on the growth ofBifidobacterium adolescentis.With the increase of acorn starch isomalto-oligosaccharide，the viable count of the probiotics increased.When glucose was substituted by the acorn starch isomalto-oligosaccharide with concentration 1.5%，after 24 h culture，the count of theBifidobacterium adolescentiswas（7.22±0.15）%，which had reach to maximum quantity，and acorn starch isomalto-oligosaccharide promoted the growth rates of theBifidobacterium adolescentisand made its stable growth periods earlier.The acorn starch isomalto-oligosaccharide low，medium，and high dose groups all could improve the function of constipation and defecation，in which，the laxative effect of medium dose group was better.The result showed that the acorn starch isomalto-oligosaccharide had good function of promoting the proliferation ofBifidobacteriumand the laxative effect.