Milk oligopeptide inhibition of (α)-tocopherol fortified linoleic acid oxidation

Dietary zinc deficiency impairs desaturation and elongation of linoleic acid, but nothing is so far known about its effects on net whole-body utilization of linoleic or α-linolenic acids. By measuring intake, whole-body accumulation, and excretion of linoleic and α-linolenic acids, together with accumulation of their long-chain products, we hypothesized that a quantitative estimate could be obtained of their whole-body disappearance (apparent oxidation). This was evaluated in pregnant and nonpregnant rats given a low-zinc diet (3.4 vs. 34 mg zinc/kg diet in zinc-adequate controls). In the nonpregnant controls, low zinc intake did not significantly affect food intake or weight gain but did reduce whole-body accumulation of desaturated and (or) elongated products of linoleic and α-linolenic acids. In pregnant rats, low zinc intake reduced food intake and weight gain and doubled whole-body disappearance of linoleic and α-linolenic acids relative to that in the zinc-adequate controls. In contrast to the maternal fatty acid changes, low zonc intake had no significant effect on linoleic acid accumulation in the fetuses. We conclude that low zinc intake during pregnancy prevents the normal accumulation of long-chain fatty acids and differentially depletes maternal whole-body stores of linoleic and α-linolenic acids.Key words: fetus, linoleic acid, oxidation, pregnancy, zinc.

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Anthocyanin-rich purple potato flake extract has antioxidant capacity and improves antioxidant potential in rats

British Journal Of Nutrition ◽

10.1017/bjn20061928 ◽

2006 ◽

Vol 96 (6) ◽

pp. 1125-1134 ◽

Cited By ~ 58

Author(s):

Kyu-Ho Han ◽

Mitsuo Sekikawa ◽

Ken-ichiro Shimada ◽

Makoto Hashimoto ◽

Naoto Hashimoto ◽

...

Keyword(s):

Linoleic Acid ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Control Group ◽

Acid Oxidation ◽

Mrna Levels ◽

Scavenging Activity ◽

Potato Flake ◽

Linoleic Acid Oxidation ◽

Potato Flakes

Anthocyanins from various vegetables and fruits have antioxidant activities, however, the bioactivities of coloured potato anthocyanins are not well studied. We examined the antioxidant capacities of pigmented fractions from purple potato flakes in vitro, and the antioxidant potentials of purple potato flakes in vivo. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity of the pigmented fraction from Hokkai no. 92 (H92) potato flakes was higher than that from Kitamurasaki (KM) potato flakes. Extracts equivalent to 600 μg pigmented fractions from KM and H92 potato flakes inhibited linoleic acid oxidation in the order trolox>H92 ≥ KM>control. Rats were fed 25 % KM or H92 potato flake diets for 4 weeks. The major anthocyanin was identified as petanin. Control rats were fed a diet with cornstarch instead of potato flakes for 4 weeks. The serum antioxidant potential level in the H92 group was significantly higher than that in the control group. The degree of hepatic lipid peroxidation in the H92 group was significantly lower than that in the control group. Hepatic Cu/Zn-superoxide dismutase (SOD), Mn-SOD and glutathione peroxidase (GSH-Px) mRNA levels in the H92 group were significantly higher than those in the control group. Similar significant differences in Cu/Zn-SOD and Mn-SOD mRNA levels between the KM and control groups were found. The present results suggest that purple potato flakes have antioxidant functions with regard to radical scavenging activity and inhibition of linoleic acid oxidation, and that they improve the antioxidant potentials in rats by enhancing hepatic Mn-SOD, Cu/Zn-SOD and GSH-Px mRNA expression.

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