The effects of cereal-derived β-glucans and enzyme supplementation on intestinal microbiota, nutrient digestibility and mineral metabolism in pigs

Effect of sulfated yeast beta-glucan on cyclophosphamide-induced immunosuppression in chickens

Immunosuppression is a condition that causes large economic losses in the poultry industry. To investigate the effect of sulfated yeast beta-glucan on immunosuppression, two hundred and fifty 11-day-old chickens were randomly assigned to five groups, and except for the normal control group, injected with cyclophosphamide once a day for 3 successive days. At 14 days of age, sulfated yeast beta-glucan from Saccharomyces cerevisiae(sGSC) was orally administered at three doses to the chickens in three experimental groups for 14 days. On days 7 and 14 after the first sGSC dose, serum cytokine concentrations and peripheral lymphocyte proliferation were measured. Gut microbiota, organ index, and histopathological changes in the bursa were investigated on day 14. The results demonstrated that at 4 mg/kg, sGSC could significantly enhance the bursa index and IFN-γ and IL-6 concentrations, decrease TGF-β1 concentration, and promote lymphocyte proliferation; it could effectively decrease histopathological changes in the bursa and improve gut Bifidobacterium and Lactobacillus populations in cecal digesta of chickens compared with the model control group. This indicated that sGSC could effectively alleviate immunosuppression and regulate the beneficial microbiota in the gut.

Inonotus obliquus polysaccharide regulates gut microbiota of chronic pancreatitis in mice

Polysaccharide is efficient in attenuation of metabolic ailments and modulation of gut microbiota as prebiotics. The therapeutic effect of Inonotus obliquus polysaccharide (IOP) on chronic pancreatitis (CP) in mice has been validated in our previous study. However, it is not clear whether IOP is conducive to maintaining the homeostasis between gut microbiota and host. The aim of this study is to testify the potential effects of IOP on gut microbiota composition and diversity in mice with CP. The changes in glutathione peroxidase (GSH-P_X), total antioxidant capacity (TAOC), tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), lipase and trypsin levels were measured by commercial assay kits, meanwhile the gut microbiota composition and diversity were analyzed by high throughput sequencing. The IOP treatment increased GSH-P_X and TAOC levels, and decreased TNF-α, TGF-β, lipase and trypsin levels in CP mice. It was also observed that gut microbiota in IOP treated groups were less diverse than others in terms of lower Shannon diversity index and Chao 1 estimator. IOP increased the proportion of Bacteroidetes and decreased that of Firmicutes at phylum level. Bacteroidetes was found positively correlated with GSH-P_X and TAOC, and Firmicutes correlated with TNF-α, TGF-β, and lipase. In conclusion, administration of IOP could regulate gut microbiota composition and diversity to a healthy profile in mice with CP, and some bacterial phylum significantly correlated with characteristic parameters.

Impact of whole grains on the gut microbiota: the next frontier for oats?

The gut microbiota plays important roles in proper gut function and can contribute to or help prevent disease. Whole grains, including oats, constitute important sources of nutrients for the gut microbiota and contribute to a healthy gut microbiome. In particular, whole grains provide NSP and resistant starch, unsaturated TAG and complex lipids, and phenolics. The composition of these constituents is unique in oats compared with other whole grains. Therefore, oats may contribute distinctive effects on gut health relative to other grains. Studies designed to determine these effects may uncover new human-health benefits of oat consumption.

Prebiotic effects of almonds and almond skins on intestinal microbiota in healthy adult humans

Almonds and almond skins are rich in fiber and other components that have potential prebiotic properties. In this study we investigated the prebiotic effects of almond and almond skin intake in healthy humans. A total of 48 healthy adult volunteers consumed a daily dose of roasted almonds (56 g), almond skins (10 g), or commercial fructooligosaccharides (8 g) (as positive control) for 6 weeks. Fecal samples were collected at defined time points and analyzed for microbiota composition and selected indicators of microbial activity. Different strains of intestinal bacteria had varying degrees of growth sensitivity to almonds or almond skins. Significant increases in the populations of Bifidobacterium spp. and Lactobacillus spp. were observed in fecal samples as a consequence of almond or almond skin supplementation. However, the populations of Escherichia coli did not change significantly, while the growth of the pathogen Clostridum perfringens was significantly repressed. Modification of the intestinal microbiota composition induced changes in bacterial enzyme activities, specifically a significant increase in fecal β-galactosidase activity and decreases in fecal β-glucuronidase, nitroreductase and azoreductase activities. Our observations suggest that almond and almond skin ingestion may lead to an improvement in the intestinal microbiota profile and a modification of the intestinal bacterial activities, which would induce the promotion of health beneficial factors and the inhibition of harmful factors. Thus we believe that almonds and almond skins possess potential prebiotic properties.

Gut microbiota, host health, and polysaccharides

The intestinal microbiota is a complicated ecosystem that influences many aspects of host physiology (i.e. diet, disease development, drug metabolism, and regulation of the immune system). It also exhibits spatial patterning and temporal dynamics. In this review, the effects of internal and external (environmental) factors on intestinal microbiota are discussed. We describe the roles of the gut microbiota in maintaining intestinal and immune system homeostasis and the relationship between gut microbiota and diseases. In particular, the contributions of polysaccharides, as the most abundant diet components in intestinal microbiota and host health are presented. Finally, perspectives for research avenues relating to gut microbiota are also discussed.

Effects of cereal β-glucans and enzyme inclusion on the porcine gastrointestinal tract microbiota

This study was designed to evaluate the effect barley-based diets vs. oats based diets on levels of Lactobacillus, Bifidobacterium and Enterobacterium in the porcine gastrointestinal tract (GIT). In addition the effect of enzyme supplementation in both diets was explored. Twenty-eight boars were used in a 2 × 2 factorial arrangement and were assigned to 1 of 4 dietary treatments: barley-based (B) diet; barley-based diet plus an enzyme supplement (B + ES); oat-based (O) diet or oat-based diet plus an enzyme supplement (O + ES). The enzyme supplement contained endo-1,3-β-glucanase and endo-1,4-β-xylanase. Faecal samples were collected from the pigs prior to initiations of the experiment and at slaughter. At slaughter digesta samples were collected from the stomach, ileum, caecum, proximal and distal colon. Alterations in Lactobacillus species composition in the gastrointestinal tract (GIT) were analysed by genus-specific PCR - denaturing gradient gel electrophoresis (DGGE). DGGE profiles indicated that cereal source provoked shifts in Lactobacillus population. The most diverse populations of lactobacilli emerged after feeding the O diets. Enzymes inclusion altered the composition of Lactobacillus species prevalent throughout the GIT in animals fed the B diet, causing a shift in the dominant lactobacilli present in the caecum and proximal colon. No such effect was evident in animals fed the enzyme supplemented O + ES diet. Microbial plate counts revealed that the O diets gave rise to higher counts of Lactobacillus in the caecum and colon and Bifidobacterium counts in the ileum, caecum and colon than the B diets. The O diet caused a 2 log increase in Enterobacterium counts in the proximal colon, no such effects were observed in animals fed the B, the B + ES or the O + ES diets. Overall both O diets had a more positive influence on the counts of the beneficial microorganisms and richness of the Lactobacillus population in the porcine GIT.