The Protective Effect of Hippophae Rhamnoides Carotenoid Extract Against Lipid Peroxidation in Crude Vegetable Oils

摘要

Vegetable oils are important elements of the human diet because they contain essential nutritional factors. Due to the manufacturing processes or inadequate conditions of storage, they may also contain lipid oxidation products that are toxic to the body. The purpose of this paper is to test the protective effect of carotenoid-rich extracts obtained from the fruits of Hippophae rhamnoides on crude sunflower, pumpkin and olive oils oxidative processes. In order to evaluate the effect of antioxidant carotenoids, three stages were followed: thermal induction of lipid peroxidation in the presence of AAPH (2,2'-Azobis(2-amidinopropane) dihydrochloride); determination of the level of lipid peroxidation in oxidized oils in the presence and absence of antioxidants, by quantifying the concentration of conjugated dienes and malonyl dialdehyde (MDA); determination of the level of lipid peroxidation by evaluating the profile of the fatty acids and the ratio between the saturated and unsaturated fatty acids (UFA / SFA), using an GC-MS method. In the case of sunflower oil, it was observed that sea buckthorn fruit extract significantly decreased MDA concentration but does not significantly reduce the concentration of conjugated dienes. The protective effect of carotenoids is more evident in the case of oil from pumpkin seeds. In the olive oil, unlike the first two types of oils, the carotenoids extract inhibits both the MDA and the conjugated dienes formation to a lesser extent, statistically insignificant. Overall, the ratio UFA / SFA decreases in crude oxidized oils. In the oils in which carotenoids were added was observed an increase in the UFA / SFA ratio. Carotenoids fraction from sea buckthorn fruits, rich in xanthophyllsa€? esters, possess a good antioxidant effect, protecting vegetable oils against peroxidation processes induced in the presence of AAPH.