Feeding resistant starch affects fecal and cecal microflora and short-chain fatty acids in rats.

Abstract

The effects of different forms of resistant potato starch (RS) on the major microbial population groups and short-chain fatty acids (SCFA) in the cecum and feces of rats were studied over a 5-mo feeding period. Thirty 8-wk-old male Wistar rats, averaging 210 g initial body weight, were adapted for 7 d to a balanced basal diet containing 60% waxy maize starch devoid of any RS. On d 8, three groups of 10 rats each were fed diets containing the following forms of starch: 1) rapidly digestible waxy maize starch (basal diet), 2) a mixture of 83.3% waxy maize starch and 16.7% native granular potato starch (RS 1), or 3) a mixture of 33.3% waxy maize starch and 66.7% modified potato starch (RS 2). The final RS content in RS 1 and RS 2 was 10%. Fecal samples were collected at d 8 and 1, 3, and 5 mo after the start of the experiment. Cecal contents were taken after 5 mo. The colony counts of microbial groups did not vary with time in the control or the RS 1 group (P > .05). Only the number of Bacteroides/fusobacteria decreased between mo 1 and 5 in rats fed RS 1 (P < .05). The RS 2 diet led to a significant increase in total culturable bacteria, lactobacilli, streptococci, and enterobacteria between mo 1 and 5. The RS 1 and RS 2 diets stimulated the growth of bifidobacteria. Cecal numbers of lactobacilli, streptococci, and enterobacteria were higher in rats fed RS 2 than in rats fed RS 1 or control diet (P < .05). Lactobacillus cellobiosus occurred only in rats fed RS 1 or RS 2. Acetate increased in mo 3 compared with d 8 in all groups (P < .05). The fecal and cecal SCFA displayed higher concentrations of acetate and propionate and a higher molar proportion of propionate in RS 2 than in RS 1 or control rats (P < .05). Stimulation of bifidobacteria, lactobacilli, and SCFA may be useful for the suppression of pathogenic organisms in the colon.

Bioavailability of Glucosyl Hesperidin in Rats

“…22) Moreover, it has been shown that cecal contents have an abundance of intestinal bacteria and that this microflora producesglucosidases as well as -glucosidases. 23,24) Furthermore, Kometani et al have reported that G-hesperidin is hydrolyzed to hesperidin by -glucosidases, but that it can not undergo the action of -glucosidases. 10) On the basis of these findings, our observations suggest that orally administered G-hesperidin is initially hydrolyzed to hesperidin by small intestinal -glucosidases, and that released hesperidin is subsequently hydrolyzed to hesperetin by -glucosidases from intestinal bacteria.…”

Effects of Rice Starch-Isoflavone Diet or Potato Starch-Isoflavone Diet on Plasma Isoflavone, Plasma Lipids, Cecal Enzyme Activity, and Composition of Fecal Microflora in Adult Mice.

“…Different types of starch affect the composition of fecal microflora and short-chain fatty acid production (6). Resistant starch is utilized by intestinal microflora (6) and seems to affect the cecal and colonic functions (7).…”

Adhesion of Bifidobacteria to Granular Starch and Its Implications in Probiotic Technologies

“…A range of human intestinal bacteria can ferment soluble starch; the most numerically dominant of these bacteria are members of the genera Bacteroides, Bifidobacterium, Fusobacterium, and Butyrivibrio (19). However, in animal models, inclusion of resistant starches in the diet has been shown to increase the population of bifidobacteria in the intestinal tract (4,5,16,25,29). Resistant starches have therefore also been proposed as potential prebiotics.…”