Manipulation of colonic bacteria and volatile fatty acid production by dietary high amylose maize (amylomaize) starch granules

Abstract

Aims: To study the effects of amylomaize starch and modified (carboxymethylated and acetylated) amylomaize starches on the composition of colonic bacteria and the production of volatile fatty acids, in mice. Methods and Results: Balb ⁄ c mice were fed with experimental diets containing various amount of amylomaize and modified amylomaize starches. Colonic bacterial populations and short-chain fatty acids were monitored. Results showed that the increases in indigenous bifidobacteria were detected in mice fed all starches tested; however, the highest numbers were observed in the group fed with 40% unmodified amylomaize starch. The starch type influenced the populations of indigenous Lactobacillus, Bacteroides and coliforms. High Lactobacillus numbers were achieved in the colon of mice fed with high concentration of amylomaize starch. Acetylated amylomaize starch significantly reduced the population of coliforms. In addition, orally dosed amylomaize utilizing bifidobacteria reached their highest levels when fed together with amylomaize or carboxymethylated amylomaize starch and in both cases butyrate levels were markedly increased. Conclusions: These results indicate that different amylomaize starches could generate desirable variation in gut microflora and that particular starches may be used to selectively modify gut function. Significance and Impact of Study: Amylomaize starch appeared to enhance the desirable composition of colonic bacteria in mice, and suggested it possessed the potential prebiotic properties. Therefore, resistant starch and its chemical derivatives may exert beneficial impacts to the human colon.

Effects of High Amylose Maize Starch and Clostridium butyricum on Metabolism in Colonic Microbiota and Formation of Azoxymethane‐Induced Aberrant Crypt Foci in the Rat Colon

“…These observations suggest that the intestinal microbiota were changed by the administration of HAS and CBM588. It is known that the fecal number of Bifidobacterium increases when HAS is fed to pigs (5) and mice (48). However, there are very few bacterial strains that can utilize HAS, although there are many kinds of bacterial species that can utilize amylopectin maize starch (49).…”

Increased probiotic yogurt or resistant starch intake does not affect isoflavone bioavailability in subjects consuming a high soy diet

“…Although we did not determine gastrointestinal microbial activity in the current study, prebiotic effects have been reported after 2 -4 weeks of daily RS intake of between 15 and 55 g (38-42), thus it is likely the RS intake in the current study had a similar effect. Resistant starch specifically stimulates the growth of bifidobacteria in the 13 colon (15,43) and increases caecal lactobacilli and bifidobacteria levels in human flora-associated rats (16). Bifidobacteria can hydrolyze daidzin and genistin from soy milk to their respective aglycones (44) and metabolize daidzein in human faecal samples (45,46) and these effects have been attributed to its β-glucosidase activity (36,44).…”

Effects of Resistant Starch Intake in Humans

“…SCFAs are one of the most essential microbial products affecting a number of physiological processes such as energy utilization, host-microbe signaling, production of secondary bile acids, control of colonic pH, and gut motility. In addition, SCFAs play a role in epithelial cell proliferation and are associated with reduced diet-induced DNA damage and decreased precancerous lesions [30]. SCFAs are metabolized rapidly by the colon epithelial cells, referred to a colonocytes, which line the villi of the colon.…”