Effect of heat processing on the profiles of trans fatty acids and conjugated linoleic acid in butter oil

Sman or traditional butter oil (TBO) is known to be rich in saturated fatty acids (SFA). Meanwhile, published information about trans fatty acids (TFAs) content in TBO remains unexplored. Therefore, a comparison of the fatty acid (FA) composition of traditional butter (TB) and (TBO) with emphasis on geometric and conjugated linoleic acid (CLA) isomers was undertaken. Both TB and TBO accounted for a high level of SFA with significant high content in TBO (p < 0.05). Total TFAs in TBO were more than twice the content in TB (8.23% vs. 3.85%, respectively, p < 0.01). An increase by 1.81 and 2.9 times was observed for trans monounsaturated FAs and trans polyunsaturated FAs in TBO compared to TB, respectively. Vaccenic acid (VA), the predominant TFA in both TB and TBO, was increased by 100% in TBO (p < 0.001). Trans-linoleic acid isomers were 1.84-fold higher in TBO than in TB. The contribution that CLA made to the total FA was increased by 1.48-fold for TBO. In general, it was found that TBO contains high levels of TFAs and CLA. Thus, TBO represents a mixture of FAs with different configurations from natural and technological origins, having potential conflicting effects on human health.Keywords: Trans-fatty acids, conjugated linoleic acid, butter oilAfrican Journal of Biotechnology Vol. 12(21), pp. 3333-334

The intake of high fat diet with different trans fatty acid levels differentially induces oxidative stress and non alcoholic fatty liver disease (NAFLD) in rats

<p>Abstract</p> <p>Background</p> <p><it>Trans</it>-fatty acids (TFA) are known as a risk factor for coronary artery diseases, insulin resistance and obesity accompanied by systemic inflammation, the features of metabolic syndrome. Little is known about the effects on the liver induced by lipids and also few studies are focused on the effect of foods rich in TFAs on hepatic functions and oxidative stress. This study investigates whether high-fat diets with different TFA levels induce oxidative stress and liver dysfunction in rats.</p> <p>Methods</p> <p>Male Wistar rats were divided randomly into four groups (n = 12/group): C receiving standard-chow; Experimental groups that were fed high-fat diet included 20% fresh soybean oil diet (FSO), 20% oxidized soybean oil diet (OSO) and 20% margarine diet (MG). Each group was kept on the treatment for 4 weeks.</p> <p>Results</p> <p>A liver damage was observed in rats fed with high-fat diet via increase of liver lipid peroxidation and decreased hepatic antioxidant enzyme activities (superoxide dismutase, catalase and glutathione peroxidase). The intake of oxidized oil led to higher levels of lipid peroxidation and a lower concentration of plasma antioxidants in comparison to rats fed with FSO. The higher inflammatory response in the liver was induced by MG diet. Liver histopathology from OSO and MG groups showed respectively moderate to severe cytoplasm vacuolation, hypatocyte hypertrophy, hepatocyte ballooning, and necroinflammation.</p> <p>Conclusion</p> <p>It seems that a strong relationship exists between the consumption of TFA in the oxidized oils and lipid peroxidation and non alcoholic fatty liver disease (NAFLD). The extent of the peroxidative events in liver was also different depending on the fat source suggesting that feeding margarine with higher TFA levels may represent a direct source of oxidative stress for the organism. The present study provides evidence for a direct effect of TFA on NAFLD.</p

Antioxidant Activity of the Leaf Volatile Oil and Extracts of Olea europaea L.cv. Chetoui from Northern Tunisia

This study is designed to examine the chemical composition and the in vitro antioxidant activity of the volatile oil and the extracts (polar and non-polar sub-fractions) of the methanol extract of Olea europea L. (cv) chetoui. GC and GC–MS analyses of the volatile oil from the dried leaves of the variety chetoui resulted in the identification of 32 compounds, representing 92.1% of the oil; alcohols (39.5%), aldehydes (19.1%) and ketones (12.2%) were the main groups of volatiles in the studied cultivar, comprising 70.8% of the total oil. Antioxidant activities of the samples were determined by the test system namely DPPH. The weakest radical scavenging activity was exhibited by the volatile oil (49.92%). Antioxidant activity of the non-polar sub-fraction of methanol extract was superior to the all samples tested with an inhibition of the free radical DPPH value of 64.31%. Total phenolic content of the polar and non-polar sub-fractions was 65.35 and 69.17 mg/100 g DW, respectively. In fact, the results showed no significant differences in the levels of polyphenols between sub-fractions of the methanol extract of Olea europea L. Furthermore, the amount of the total orthodiphenols was highest in the non-polar sub-fraction (219.66 mg /100 g DW). A positive correlation was observed between the antioxidant activity potential and total flavonoids content of the extracts