An effect of freeze-milling on processing properties of beta-glucan oat bran has been evaluated. A comparison with existing, patented methods of high molecular weight oat beta-glucan has been carried ...out. The new method employs raw material pre-treatment with freezing and milling in a hammer mill, resulting in significant reduction of particle size – 89% was between 80 and 50 μm in comparison with initial material when 79% were between 250 and 200 μm. Reduction of particle size also improved some process parameters of extraction technology – 30% improvement in fat removal during first stage of beta-glucan recovery was observed. The achieved pilot plant yield of product containing beta-glucan extraction was 64,03%, purity (ie. beta-glucan content), of achieved product was 84,4% and average molecular weight was about 69,500 g/mol.
•Freeze-milling efficiently reduces oat bran particle size enabling higher yield of beta-glucan recovery.•Freeze-milling can efficiently reduce molecular-weight of beta-glucan preparation.•Particle size reduction form 250–200 μm to 80–50 μm leads to 30% improvement of lipid extraction.
Protective and antioxidant properties of highly purified oat β-glucans of high and low molecular weight in liver and stomach were evaluated. The novelty in approach was to determine whether dietary ...β-glucans affect the parameters of oxidative stress directly in the stomach and indirectly in the liver, especially in inflammation states. Physicochemical properties e.g. viscoelastic was found as strictly dependent from molecular weight of oat β-glucans hence its metabolic activity could also show dependence. Three groups of rats were fed control diet and diet supplemented with low and high molecular weights oat β-glucans. Animals were divided into controls and individuals with experimentally induced intestinal inflammation. Most active in increasing of total antioxidant status was low molecular weight β-glucan. High molecular weight β-glucan supplementation inhibits lipid oxidation the most in LPS treated animals. The results obtained from experiment encourage for dietary intervention with oat β-glucans for stomach and liver protection during existing enteritis.
Food hydrocolloids impact on human health is usually associated with positive interaction within gastrointestinal track and connected immune response. One of the most underestimated organs which ...reflect pathological changes appearing systemically is spleen. Acting not only as blood storage but as active organ the spleen play an important role in innate immunity which can be stimulated by alimentary treatment of immune active food hydrocolloids. Two oat beta-glucan purified preparations with high (2,179,700 g/mol) and low (69,700 g/mol) molecular weight were prepared and their antioxidant, free radical scavenging activity, the ability to alleviate inflammatory conditions and protective properties against severe oxidant induced lipid peroxidation were evaluated.
This study was performed on rats, divided into 3 groups: fed control diet and diet supplemented with small molecular mass and large molecular mass oat beta-glucans. Within groups animals were divided into controls and individuals with experimentally induced intestinal inflammation. Low molecular weight beta-glucan diet supplementation effectively decreased oxidative stress parameters in the control groups. The supplementation with high molecular weight beta-glucan in animals with inflammation decreases lipid superoxides, 7-ketocholesterol concentration and GSSG activity in rat spleens. In conclusion, beta-glucan possesses antioxidant properties as manifested by a reduction in superoxide dismutase and reductase activity. This study also demonstrated that diet supplementation with beta-glucan improves stress oxidative parameters in the spleen. It is especially important in the case of rats with induced gut inflammation. The encouraging results obtained from our experiment enables the use of this food hydrocolloid to form food formulation with protecting health properties.
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•Impact of LPS induced enteritis on antioxidant status of spleen in rats has been recognized.•Effect of dietary supplementation with purified oat beta-glucan has been checked.•Difference in antioxidant activity of high and low molecular oat beta-glucan has been evaluated.
Purpose
: The aim of the study was to investigate the protective effect of low and high molecular weight beta-glucans on the chosen immunological parameters, markers of antioxidative potential in ...rats' colon tissue, the number of lactic acid bacteria (LAB) and the concentration of short-chain fatty acids (SCFA) in rats' faeces.
Methods
: The experiment was carried out on 72 8-week old male Sprague-Dawley rats: control (
n
= 36) and experimental (
n
= 36). In half of the animals from each group enteritis was induced by LPS (10 mg kg
−1
). Rats from the experimental group were divided into two groups receiving high (GI) or low (GII) molecular weight beta-glucans for 6 consecutive weeks.
Results
: LPS evoked enteritis in all the treated animals, manifested by changes in the levels of IL-10, IL-12 and TNF-alpha, as well as in the number of intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) in the colon tissue. Dietary supplementation with beta-glucans following LPS treatment partially reversed this effect. The changes in SCFA concentration were noted, indicating an improvement of the fermentation process in the colon. This effect coincided with an increased number of LAB, pointing at the prebiotic properties of beta-glucans. The positive influence of beta-glucans was also manifested by the improved values of antioxidative potential markers (TAS, SOD, GR and GPx activity, TBARS concentration), noted especially in rats with LPS-induced enteritis. This influence was more pronounced in the case of low molecular weight oat beta-glucan (GII).
Conclusions
: The present study showed a positive effect of beta-glucans, especially the low molecular weight form, on the colon tissue of healthy rats, as well as animals with LPS-induced enteritis.
Effect of oat beta-glucans on colon of rats.
Letter to the Editor Suchecka, Dominika; Banasik, Marek; Zhu, Yiliang ...
The Journal of Toxicological Sciences,
2011/10/01, Volume:
36, Issue:
5
Journal Article
PDF
