Chemical composition and bioactivities of the polyphenolic-rich extract of Ormenis africana Jord. and Fourr

Ormenis africana is an endemic North African species used in folk medicine because of its hypoglycemic property. In this study, the α-amylase and α-glucosidase inhibition and antioxidant activities of the polyphenolic-rich extract from O. africana were determined. The chemical composition was made using liquid chromatography with photodiode array and electrospray ionization mass spectrometry method and the identification of phenolics was assessed by comparing their retention times and ultraviolet and mass spectra with those of the standards and/or reported in the literature. The total phenolic content was estimated by the Folin–Ciocalteu method. The antidiabetic potential was estimated by the determination of α-amylase and α-glucosidase inhibition in vitro. Four assays were used for the evaluation of antioxidant activity of the extracts. Seventeen phenolic compounds were detected. The major peaks are chlorogenic acid, 5-O-di-caffeoylquinic acid, and apigenin and luteolin derivatives. The polyphenolic-rich extract showed remarkable α-amylase and α-glucosidase inhibition activity in a concentration dependent manner. Furthermore, the extract also demonstrated high antioxidant activities. O. africana can serve as a potential natural source for the development of a novel α-amylase and α-glucosidase inhibitory agents against diabetic complications.