Effect of Lotus Seed Resistant Starch on Lactic Acid Conversion to Butyric Acid Fermented by Rat Fecal Microbiota

The aim was to investigate the effect of lotus seed resistant starch (LRS) on lactic acid (LA) conversion to butyric acid (BA) fermented by rat fecal microbiota to construct an acetyl CoA pathway. According to growth curves, the microbiota compositions at 10 and 36 h were further analyzed. The microbiota in the LRS group had higher richness and diversity compared to glucose (GLU) and high amylose maize starch (HAMS). Moreover, LRS and isotope LA promoted the growth of Lactobacillus and Bifidobacterium, promoted BA production, and inhibited the growth of Escherichia–Shigella. The BUT pathway played a dominant role in three groups. At 10 h, Escherichia–Shigella and Bifidobacterium showed a negative correlation with BUT and a positive correlation with BUK, whereas Escherichia–Shigella, Allobaculum, Bifidobacterium, and Ralstonia showed a positive correlation with BUT and BUK at 36 h. [3-¹³C] LA was converted to [4-¹³C] BA by the isotope labeling technique. Finally, LRS promoted LA conversion to BA mainly by the BUT pathway in intestinal microbiota, especially including Allobaculum, Bifidobacterium, and Ralstonia.