A comparative study of physicochemical properties, antioxidant and enzyme inhibition activities of oils extracted from seeds of seven new sunflower (Helianthus annuus L.) lines

This study was aimed to evaluate the physicochemical properties and chemical profile of seeds oil obtained from new seven sunflower (Helianthus annuus L.) lines as well as their antioxidant and enzyme inhibition activity. The seeds powder was extracted by maceration in n-hexane. The oil content of the seven lines was ranged from 20.04% to 36.65% and was either yellow or pale yellow in color. No significant variations were observed on the refractive index (1.46 unit) of the oil. Oils of the seven lines were significantly (p < 0.05) different in their saponification values (32.13-282.66 mg KOH/g oil), peroxide values (1.76-13.26 mg KOH/g-oil), acid values (0.016-1.766 mg KOH/g oil) and free fatty acids content (6.26-72.23 mg KOH/g-oil). The chemical profile of the oil revealed that line APO42 contained the highest amount of monounsaturated fatty acids (55.9%). All the seven lines contained a considerable amount of linoleic acid (27.5%-42.5%), and it represented the major compound in lines BOH3 (42.5%) and H1733 (39.8%). The variation was remarkable in their oleic acid content where the highest amount was observed in lines APO42 (55.4%) and APO43 (42.2%), respectively. Lines BOH3, APO43, APO41, and H1733 exerted the best total antioxidant activity in addition to their capacity to reduce Cu2+ and Fe3+, while lines H1733 and APO43 had a metal chelating activity as well. All oils showed weak acetylcholinesterase, butyrylcholinesterase, alpha-glucosidase and alpha-amylase inhibitory activities. Only four lines showed considerable enzyme inhibitory activity against tyrosinase enzymes. Multivariance analysis suggested that linoleic acid participated in the observed biological activity of the oils. In conclusion, these new lines might contribute to the nutritional and phytotherapeutic properties of sunflower oil in addition to other industrial applications.