Time-dependent fermentation of different structural units of commercial pectins with intestinal bacteria.

Many of the proposed health-related properties of pectins are based on their fermentability in the large intestine, but detailed structure-related studies on pectin fermentation have not been reported so far. Here, pectin fermentation kinetics were studied with a focus on structurally different pectic polymers. Therefore, six commercial pectins from citrus, apple, and sugar beet were chemically characterized and fermented in in vitro fermentation assays with human fecal samples over different periods of time (0 h, 4 h, 24 h, 48 h). Structure elucidation of intermediate cleavage products showed differences in fermentation speed and/or fermentation rate among the pectins, but the order in which specific structural pectic elements were fermented was comparable across all pectins. Neutral side chains of rhamnogalacturonan type I were fermented first (between 0 and 4 h), followed by homogalacturonan units (between 0 and 24 h) and, at last, the rhamnogalacturonan type I backbone (between 4 and 48 h). This indicates that fermentation of different pectic structural units might take place in different sections of the colon, potentially affecting their nutritional properties. For the formation of different short-chain fatty acids, mainly acetate, propionate, and butyrate, and the influence on microbiota, there was no time-dependent correlation regarding the pectic subunits. However, an increase of members of the bacterial genera Faecalibacterium, Lachnoclostridium, and Lachnospira was observed for all pectins.

Specific Wheat Fractions Influence Hepatic Fat Metabolism in Diet-Induced Obese Mice.

Low whole grain consumption is a risk factor for the development of non-communicable diseases such as type 2 diabetes. Dietary fiber and phytochemicals are bioactive grain compounds, which could be involved in mediating these beneficial effects. These compounds are not equally distributed in the wheat grain, but are enriched in the bran and aleurone fractions. As little is known on physiological effects of different wheat fractions, the aim of this study was to investigate this aspect in an obesity model. For twelve weeks, C57BL/6J mice were fed high-fat diets (HFD), supplemented with one of four wheat fractions: whole grain flour, refined white flour, bran, or aleurone. The different diets did not affect body weight, however bran and aleurone decreased liver triglyceride content, and increased hepatic n-3 polyunsaturated fatty acid (PUFA) concentrations. Furthermore, lipidomics analysis revealed increased PUFA concentration in the lipid classes of phosphatidylcholine (PC), PC-ether, and phosphatidylinositol in the plasma of mice fed whole grain, bran, and aleurone supplemented diets, compared to refined white flour. Furthermore, bran, aleurone, and whole grain supplemented diets increased microbial α-diversity, but only bran and aleurone increased the cecal concentrations of short-chain fatty acids. The effects on hepatic lipid metabolism might thus at least partially be mediated by microbiota-dependent mechanisms.

The influence of an anti-inflammatory diet on gingivitis. A randomized controlled trial.

AIM: Aim of this study was to investigate the influence of an anti-inflammatory diet on different parameters in patients with gingivitis. MATERIALS AND METHODS: Thirty patients were randomly allocated to an experimental and a control group stratified by their plaque values. The experimental group had to change to a diet low in processed carbohydrates and animal proteins, and rich in omega-3 fatty acids, vitamin C, vitamin D, antioxidants, plant nitrates and fibres for 4 weeks. The control group did not change their diet. Both groups suspended interdental cleaning. Periodontal parameters were assessed by a blinded dentist. Serological and subgingival plaque samples were taken at baseline and end. RESULTS: While there were no differences regarding the plaque values, the experimental group showed a significant reduction in gingival bleeding (GI Baseline: 1.04 ± 0.21, GI End: 0.61 ± 0.29, p < 0.05), a significant increase in Vitamin D values and a significant weight loss. There were no inter-group differences regarding the inflammatory serological parameters, the serological omega fatty acids, nor the subgingival microbiome composition. CONCLUSION: The evaluated diet could significantly reduce gingivitis in a clinically relevant range, while serological inflammatory parameters and the subgingival microbiome seem to be unaffected in this study duration. (German Clinical Trials Register; DRKS00009888).