Dietary supplementation with rice bran or navy bean alters gut bacterial metabolism in colorectal cancer survivors

Abstract

Scope Heat-stabilized rice bran and cooked navy bean powder contain a variety of phytochemicals that are fermented by colonic microbiota and may influence intestinal health. Dietary interventions with these foods should be explored for modulating colorectal cancer risk. Methods and results A randomized-controlled pilot clinical trial investigated the effects of eating heat-stabilized rice bran (30g/day) or cooked navy bean powder (35g/day) on gut microbiota and metabolites (NCT01929122). Twenty-nine overweight/obese volunteers with a prior history of colorectal cancer consumed a study-provided meal and snack daily for 28 days. Volunteers receiving rice bran or bean powder showed increased gut bacterial diversity and altered gut microbial composition at 28 days compared to baseline. Supplementation with rice bran or bean powder increased total dietary fiber intake similarly, yet only rice bran intake led to a decreased Firmicutes:Bacteroidetes ratio and increased short chain fatty acids (propionate and acetate) in stool after 14 days but not at 28 days. Conclusion These findings support modulation of gut microbiota and fermentation by-products by heat-stabilized rice bran and suggest that foods with similar ability to increase dietary fiber intake may not have equal effects on gut microbiota and microbial metabolism.

Longitudinal impact of oral probiotic Lactobacillus acidophilus vaccine strains on the immune response and gut microbiome of mice

“…These results could be attributed to the compound effect of the probiotic vaccine and the prebiotic rice bran in this case. Modulation of the microbiome utilizing rice bran 51,11 and the effects of diet are well supported 52,53,54 . Taken together these results highlight the opportunity for synbiotics, combining probiotics and prebiotics to improve efficacy of vaccination.…”

Effects of Short-Term Intake of Wheat Bran with Different Particle Sizes on the Murine Intestinal Environment

“…High dietary fiber intake is reported to increase the phylum Bacteroidetes in the intestine of mammals such as mouse, pig and human (Miyazato et al, 2016;Magistrelli et al, 2016;Sheflin et al, 2016). Previous studies have shown that 8-week intake of whole-grain wheat increases the ratio of Bacteroidetes at the phylum level and Prevotella at the genus level in human (Vitaglione et al, 2015), and that SCFA production in mice is elevated by long-term intake (4 weeks) of whole wheat and wheat bran (Garcia-Mazcorro et al, 2016;Takahashi et al, 1999).…”

“…Wheat bran contains high levels of dietary fiber, including lignin, cellulose, arabinoxylan (pentosan) and other non-starch polysaccharides (Zhao and Dong, 2016). High-fiber foods such as cereal bran are known to provide human health benefits by changing intestinal microbiota (Kontula et al 1998;Sheflin et al, 2016;Ou et al, 2016). Because dietary fiber is resistant to digestive enzymes, it reaches the distal intestine and is used as an energy source for intestinal microbiota (Gibson et al, 1995).…”

The Effect of Hops (Humulus lupulus L.) Extract Supplementation on Weight Gain, Adiposity and Intestinal Function in Ovariectomized Mice

“…The clear supernatant was transferred for UHPLC-MS analysis. Analysis was performed at the Colorado State University Proteomics and Metabolomics Core Facility on a Waters (Millford, MA, USA) Acquity UHPLC coupled to a Waters Xevo TQ-S triple quadrupole mass spectrometer, as described previously [29]. Chromatographic separations were carried out on a Waters HSS T3 stationary phase (1 × 100 mm, 1.8 µM).…”