Evaluation of the Vitamin E Content, Phenolic Compounds Profile and Antioxidant Activity of Some Citrus Seeds Oils

Abstract

The aim of this research work is to evaluate the vitamin E contents, phenolic compound profiles and the antioxidant activity of seed oils extracted from fruits of some citrus plants and to determine the correlation between these parameters and antioxidant activity of the seed oils. The oils were extracted using Soxhlet extractor, the vitamin E content and the phenolic compounds profiles were determined using chromatographic technique while their antioxidant abilities were investigated using 1, 1 – diphenyl- 2-picrylhydrazyl (DPPH) radical and ferric reducing antioxidant power (FRAP) assays. The oils had relatively high vitamin E contents (7.28- 24.48mg/100g) with grapefruit significantly having the highest amount. Gallic acid and some other phenolic compounds were detected in appreciable amount in the oils and the oils showed good antioxidant ability. There was a strong correlation between the vitamin E content, phenolic compounds profile and antioxidant activity of the extracted oil. Therefore, seeds from these plants could be used as sources of oils for pharmaceutical, cosmetics and food industries to produce dietary antioxidants and bioactive compounds thus helping to prevent occurrence of certain deadly diseases associated with generation of free radicals instead of regarding them as waste.