PHYTOCHEMICAL CONSTITUENTS AND FREE RADICALS SCAVENGING ACTIVITY OF EXTRACTS FROM SEA BUCKTHORN FRUITS (HIPPOPHAE RHAMNOIDES)

Abstract

Due to its high content of ascorbic acid, tocopherols, polyphenols, carotenoids, and selenium, sea buckthorn (Hippophae rhamnoides) has an intense antioxidant action. Because, in certain situations, some synthetic antioxidants (BHT, BHA, BHQ) can generate allergies, asthma, rashes or other disorders, plants represent a healthy alternative for chemical substances used to preserve the quality of foods. Sea buckthorn (Hippophae rhamnoides) is a fascinating plant with diverse uses, such as the control of soil erosion, and source of nutrition, drugs, and skin-care products. In this study, we investigated the phytochemical constituents and the ability of Hippophae rhamnoides water-acetonic and alcoholic extracts to act as scavenger of reactive oxygen species. The quantification of total soluble phenols was based on the reduction of phosphomolybdic acid by phenols in aqueous alkali. Hydroxyl radicals were generated by the Fe 3+ /EDTA/ascorbate system, and assayed by the evaluation of deoxyribose degradation using thiobarbituric acid method. Scavenging of hydrogen peroxide was evaluated by a spectrophotometric method. Hypochlorous acid scavenging activity was tested by measuring the inhibition of hypochlorous acid induced by 5-thio-2-nitrobenzoic acid oxidation to 5,5'-dithiobis-2-nitrobenzoic acid. The radical scavenging activities were compared with standard antioxidants such BHA and BHT. The results indicated that Hippophae rhamnoides extracts contain polyphenols that act as scavenger of hydroxyl radicals, hydrogen peroxide, and hypochlorous acid.