1,721,104 research outputs found
Effect of the ratio of casein phosphopeptides to calcium (w/w) on passive calcium transport in the distal small intestine of rats
No full textWe investigated the influence of different ratios between casein phosphopeptides and calcium (CPP/Ca) in intestinal lumen on passive Ca transport across the distal small intestine of rats in vitro
Polyphenol content and total antioxidant potential of selected Italian wines.
No full textThe total antioxidant activity (TAA) of 13 typical Italian wines was determined (average 12.3 and 1.6 mM Trolox equivalents for red and white wines, respectively), and the resulting values were correlated with total phenols (1365-3326 and 96-146 mg/L for red and white wines, respectively), flavanols (203-805 and 11-49 mg/L, for red and white wines, respectively), and flavonols. Only the red wines contained appreciable amounts of flavonols (average 15.3 mg/L), with quercetin and
rutin being the most abundant, followed by myricetin, kaempferol, and isorhamnetin accounting for only 0.7-3% of TAA. The TAA of investigated wines are well correlated with phenol (r=0.9902) and flavanol (r=0.9270) content. These results confirm that red wine polyphenols are in vitro
significant antioxidants and may explain the beneficial effects of a moderate daily intake of red wines, probably through a sparing action of highly bioavailable vitamins C, E, and beta-carotene
Effects of durum wheat dietary selenium on glutathione peroxidase activity and Se content in long-term-fed rats
No full textA 120-day assay was made of Se concentration and glutathione peroxidase Se-dependent (GSHpx) activity in plasma, erythrocytes and liver of female Sprague-Dawley rats fed either a Torula diet (low Se content) or a durum wheat diet providing 28-405 micrograms of Se/kg diet. For all groups there was a strong increase for the first 20 days in plasma and liver Se; for the remaining period the increase was lower; erythrocyte Se increased, as before, in the first 60 days for groups fed 28-200 micrograms/kg diet, after this period it decreased in the groups fed high-Se diet. Plasma GSHpx activity was extremely sensitive to dietary Se levels and increased for up to 40 days of repletion, after which the trend was to plateau; liver and erythrocyte GSHpx activity increased continuously for up to 60 days of supplementation, it then remained constant. The correlation between Se in plasma, liver and erythrocytes and its GSHpx activity was statistically significant (p less than 0.001). These results suggested that in long-term-fed rats, a diet with levels of 100-400 micrograms/kg was sufficient to satisfy the rat's needs; there was no evidence of toxicity and, moreover, in all tissues, an amount of Se, probably bound to proteins with unknown functions, was present
LABORATORY ASSESSMENT AND EFFECTS OF INCREASED COLONIC FERMENTATION INDUCED BY UNABSORBABLE CARBOHYDRATES
No full textAbsorption of lycopene from single or daily portions of raw and processed tomato
No full textTo study the relationship between lycopene intake and plasma concentration, ten healthy female subjects were given one or more portions of tomato puree or fresh raw tomato containing 16.5 mg total lycopene (all-trans + cis forms). In Expt 1 subjects (n 9) were randomly assigned the single portions of the two tomato products and blood samples were collected to follow the change in plasma carotenoid concentrations within the first 12 h and on each of the following 5 d (104 h). In Expt 2 subjects (n 10) were divided into two groups of five each receiving daily dietary portions of tomato puree or fresh raw tomato containing 16.5 mg total lycopene for 7 d. Fasting blood samples were collected daily. In Expt 1 the plasma total lycopene (all-trans + cis forms) concentration, after the single portions of tomato puree and raw tomato, varied significantly over time, with a first peak reached after 6 h, a further increase after 12 h and a slow decrease until 104 h. In Expt 2, when the tomato products were given daily, there was a day-by-day increase in the plasma total lycopene concentration, and through the following week of a diet without tomato there was a gradual decrease. However, values did not return to basal concentrations. Plasma total lycopene concentration was higher after the tomato puree intake than after the raw tomato in both the first (F(1,8) 7.597; P < 0.025) and the second experiments (F(1,8) 12.193; P < 0.01) demonstrating a significant effect of food matrix on absorption
Malondialdehyde production in Jurkat T cells subjected to oxidative stress
No full textOBJECTIVE: We investigated the relation between membrane lipid peroxidation, as evaluated by malondialdehyde (MDA), and oxidative stimuli in the Jurkat T-cell line and designed a cellular model to assess the antioxidant potential of compounds. METHODS: Jurkat T cells were subjected to different concentrations of Fe(2+) ions (from 25 to 150 micromol/L) or H(2)O(2) (from 0.1 to 5 mmol/L), and MDA was determined after separation in high-performance liquid chromatography of the adduct with thiobarbituric acid. MDA production also was investigated in cells supplemented with epigallocatechin gallate and genistein and subjected to Fe(2+) oxidative treatment. RESULTS: MDA production increased with the concentration of Fe(2+), whereas H(2)O(2) had no effect at any concentration. Oxidative stress for 15 min or 2 h produced similar MDA levels. The supplementation of epigallocatechin gallate partly prevented MDA production (about 40%, P < 0.05), whereas genistein exerted no preventive effect on lipid peroxidation. CONCLUSION: We propose this cellular model, consisting of Jurkat T cells subjected to 100 micromol/L of Fe(2+) for 15 min, to study the protective effect of antioxidant supplementation against membrane lipid peroxidation
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