Selected nondigestible carbohydrates and prebiotics support the growth of probiotic fish bacteria mono-cultures in vitro

To search for nondigestible but fermentable (NDF) carbohydrates and prebiotics with a potency to promote the growth of selected bacteria in vitro. The growth of three reference bacteria strains Bacillus subtilis LMG 7135(T), Carnobacterium piscicola LMG 9839, Lactobacillus plantarum LMG 9211 and one candidate probiotic bacteria Lactobacillus delbrueckii subsp. lactis was investigated over a minimum period of 48 h in the presence of beta-glucan, xylo-oligosaccharide, arabinoxylo-oligosaccharide, inulin, oligofructose and glucose. Besides the capability to grow on inulin and oligofructose containing media, a distinct high growth in beta-glucan based substrates and a low growth in (arabino)xylooligosaccharide containing media were evident for most bacteria tested. With the exception of B. subtilis and L. plantarum, other bacteria grew equally well or even better on different substrates than on glucose. The fermentation of studied carbohydrates by these micro-organisms was dominated by the production of acetic acid as the main short chain fatty acid. Selected bacteria are able to ferment and grow on NDF and prebiotic carbohydrates but in a substrate dependent manner. This study delivers a first screening of which NDF or prebiotic carbohydrates are the most promising for aquaculture feed supplementations

Sodium ion interaction with psyllium husk (Plantago sp.)

The nature of and factors effecting sodium interactions with psyllium were investigated in vitro. In a batch extraction system, psyllium mucilage gel retained at least 50% of sodium across a range of concentrations (5–300 mg sodium per g psyllium) and pH (2–10) environments. FTIR and Na NMR analyses of psyllium gels indicated that binding was complex with non-specific multi-site interactions. The potential use of psyllium husk as a binding agent for the reduction of bioavailable sodium was therefore evaluated. The binding of sodium at physiologically relevant conditions (pH 1.2 (stomach) and 6.8 (intestine)) was studied in a gastrointestinal tract (GIT) pH simulated model. Results show consistently high sodium retention (∼50%) across the GIT model and less than 20% loss of bound sodium under the simulated intestinal pH conditions after repeated washings

Regression and stabilization of advanced murine atherosclerotic lesions: a comparison of LDL lowering and HDL raising gene transfer strategies

Both reductions in atherogenic lipoproteins and increases in high-density lipoprotein (HDL) levels may affect atherosclerosis regression. Here, the relative potential of low-density lipoprotein (LDL) lowering and HDL raising gene transfer strategies to induce regression of complex murine atherosclerotic lesions was directly compared. Male C57BL/6 LDL receptor (LDLr)−/− mice were fed an atherogenic diet (1.25% cholesterol and 10% coconut oil) to induce advanced atherosclerotic lesions. A baseline group was killed after 6 months and remaining mice were randomized into a control progression (Adnull or saline), an apolipoprotein (apo) A-I (AdA-I), an LDLr (AdLDLr), or a combined apo A-I/LDLr (AdA-I/AdLDLr) adenoviral gene transfer group and followed-up for another 12 weeks with continuation of the atherogenic diet. Gene transfer with AdLDLr decreased non-HDL cholesterol levels persistently by 95% (p < 0.001) compared with baseline. This drastic reduction of non-HDL cholesterol levels induced lesion regression by 28% (p < 0.001) in the aortic root and by 25% (p < 0.05) in the brachiocephalic artery at 12 weeks after transfer. Change in lesion size was accompanied by enhanced plaque stability, as evidenced by increased collagen content, reduced lesional macrophage content, a drastic reduction of necrotic core area, and decreased expression of inflammatory genes. Elevated HDL cholesterol following AdA-I transfer increased collagen content in lesions, but did not induce regression. Apo A-I gene transfer on top of AdLDLr transfer resulted in additive effects, particularly on inflammatory gene expression. In conclusion, drastic lipid lowering induced by a powerful gene transfer strategy leads to pronounced regression and stabilization of advanced murine atherosclerosis

Comparative prebiotic activity of mixtures of cereal grain polysaccharides

The main components of the non-starch polysaccharide (NSP) fraction of wheat flour are arabinoxylan (AX) and β-glucan. These are also present in other cereal grains, but their proportions vary with AX being the major component in wheat and rye and β-glucan in barley and oats. Therefore, it was hypothesised that these NSPs could act synergistically when fermented in vitro at the ratios present in the major foods consumed, resulting in increased prebiotic activity. AX and β-glucan were therefore tested in in vitro fermentation studies to assess their prebiotic activity when used individually and/or in different ratios. Short-chain fatty-acids (SCFAs) produced from in vitro fermentation were measured using HPLC and bacterial populations were measured using flow cytometry with fluorescence in situ hybridisation (Flow-FISH). Fermentation of AX alone resulted in a significant bifidogenic activity and increased concentrations of SCFAs, mainly acetate, after 8-24 h of fermentation, however β-glucan alone did not show prebiotic activity. The greatest prebiotic activity, based on concentration of total SCFAs and increases in total bacteria as well as beneficial Bifidobacterium and Clostridium coccoides/Eubacterium groups, was observed when AX and β-glucan were combined at a 3:1 ratio, which corresponds to their ratios in wheat flour which is major source of cereal fibre in the diet. This indicates that the population of bacteria in the human GI tract may be modulated by the composition of the fibre in the diet, to maximise the prebiotic potential

Down-regulation of endothelial TLR4 signalling after apo A-I gene transfer contributes to improved survival in an experimental model of lipopolysaccharide-induced inflammation

The protective effects of high-density lipoprotein (HDL) under lipopolysaccharide (LPS) conditions have been well documented. Here, we investigated whether an effect of HDL on Toll-like receptor 4 (TLR4) expression and signalling may contribute to its endothelial-protective effects and to improved survival in a mouse model of LPS-induced inflammation and lethality. HDL cholesterol increased 1.7-fold (p < 0.005) and lung endothelial TLR4 expression decreased 8.4-fold (p < 0.005) 2 weeks after apolipoprotein (apo) A-I gene transfer. Following LPS administration in apo A-I gene transfer mice, lung TLR4 and lung MyD88 mRNA expression, reflecting TLR4 signalling, were 3.0-fold (p < 0.05) and 2.1-fold (p < 0.05) lower, respectively, than in LPS control mice. Concomitantly, LPS-induced lung neutrophil infiltration, lung oedema and mortality were significantly attenuated following apo A–I transfer. In vitro, supplementation of HDL or apo A–I to human microvascular endothelial cells-1 24 h before LPS administration reduced TLR4 expression, as assessed by fluorescent-activated cell sorting, and decreased the LPS-induced MyD88 mRNA expression and NF-κB activity, independently of LPS binding. In conclusion, HDL reduces TLR4 expression and signalling in endothelial cells, which may contribute significantly to the protective effects of HDL in LPS-induced inflammation and lethality

Regulation of Nitric Oxide Synthase Expression by Structure Modified Arabinoxylans from Wheat Flour in Cultured Human Monocytes

This is the peer reviewed version of the following article: Zhang, Z., Smith, C. J., Ashworth, J. J., & Li, W. (2018). Regulation of Nitric Oxide Synthase Expression by Structure Modified Arabinoxylans from Wheat Flour in Cultured Human Monocytes. International Journal of Food Science & Technology, 53(5), 1294-1302. https://doi.org/10.1111/ijfs.13710 which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/ijfs.13710/full. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingThe immunomodulatory activity of the arabinoxylans (AXs) extracts from cereal sources has been reported to impart health benefits in terms of immune enhancement. This study investigated the effect of enzymatic extraction on extraction yield and structure of AXs from wheat flour pentosan fraction. Under the optimised conditions, the extraction yield of AXs reached up to 81.25%. Furthermore, the study determined whether water-extracted AXs (WEAXs) and enzyme-extracted AXs (E-WEAXs) from wheat flour were able to differentially stimulate nitric oxide (NO) secretion through increased levels of inducible nitric oxide synthase (iNOS) in human U937 monocytes. The results indicated that AXs concomitantly induced (P < 0.05) both NO and iNOS productions in U937 monocytes compared to untreated cells. Compared with WEAXs, E-WEAXs resulted in a higher proportion of low Mw (1–10 KDa) AXs (49.51% vs. 19.11% in WEAXs), a higher A/X ratio (0.83 vs. 0.48 in WEAXs) and a higher yield (12.83 ± 0.35% vs. 7.54 ± 0.47% in WEAXs). Moreover, E-WEAXs induced significantly (P < 0.05) greater NO and iNOS production per million viable cells (61.8 ± 2.7 μm and 42.41 ± 3.83 ng respectively) than WEAXs (51.6 ± 2.6 μm and 33.46 ± 1.48 ng, respectively). The findings suggest AXs may heighten innate immune activity in the absence of infection or disease through an iNOS-mediated stimulation of NO production. The immunomodulatory activity of the wheat-derived AXs was enhanced by enzyme treatment, with low Mw and high A/X ratio associated with elevated NO/iNOS levels in human monocytes compared to water extraction

Psyllium husk gel to reinforce structure of gluten-free pasta?

Gluten-free pasta is a technological challenge. The effect of Psyllium particle size, processing temperature and gel concentration on the quality of rice-based pasta was investigated. The rheological properties, i.e. maturation kinetics and mechanical spectra, of the Psyllium gels were studied and optimal conditions were set: 160–315 μm particle size, 4 g/100 g Psyllium husk concentration thermally processed at 40 ºC. Cooking quality parameters, texture properties, nutritional composition, antioxidants and digestibility of pasta were determined. Consequently, the use of Psyllium husk in gluten-free pasta showed good overall properties. Moreover, the pregelatinization step of rice flour can be eliminated, resulting in a final gluten-free pasta formulation with Psyllium gel and rice flour (50/50) with high digestibilityinfo:eu-repo/semantics/publishedVersio