In vitro antioxidant and α‐amylase inhibitory potential of methanolic and lipid fractions fromPistacia atlantica Desf. galls

Abstract

The aim of this study is to evaluate the effects of harvest period, growing region, and shapes of P. atlantica galls on the chemical composition, as well as on the antioxidant activities and ability to inhibit the carbohydrate hydrolyzing enzymes. Thus, the fatty acid composition; the determination of total sterols and tocopherols; the quantitative analysis of phenolic compounds; the antioxidant activities (DPPH•, FRAP, and ABTS•+) and the α-amylase inhibitory activity were carried out. Two shapes (spherical and semi-circular) of galls collected at different harvest periods were used in this work. The result revealed that all the methanolic, lipid extracts, and unsaponifiable fractions showed antioxidant and α-amylase inhibitory activities. Notably, the methanolic extracts from spherical galls has a higher antioxidant activity than those from semi-circular galls. Whereas, in lipid extracts, the observation is reversed. A higher α-amylase inhibitory activity for semi-circular galls was recorded in August and in September for spherical galls. Practical applications Galls are used in traditional medicine. Results from the present study suggest that galls are a good source of natural antioxidants and potential alternatives to control postprandial hyperglycemia. They can be useful for developing nutraceuticals, functional foods, and additives in food processing for health. This is the first report of α-amylase inhibitory activity for methanolic and lipid extracts from P. atlantica galls.