In vitro antidiabetic and antioxidant activities of Galega officinalis extracts

The purpose of the present study was to determine the total phenolic, flavonoid, and galegine content and antioxidant activity, as well as the in vitro antidiabetic potential of different extracts of Galega officinalis using the solvent extraction method. The results demonstrated that the highest yield of extraction (28.05%) and galegine content (17.40 ± 0.04 μg/g of sample) was obtained using water as the solvent (p < .05). However, the highest total phenolic content (TPC) (138.35 ± 0.63 mg GAE per gram of dried GOEs) and total flavonoid content (TFC) (189.12 ± 1.47 mg catechin per gram of dried GOEs) were extracted using A90 (acetone-water, 90:10) solvent. A90 extract exhibited the highest inhibition of sucrase activity (91.42%) (p < .05). Also, the inhibitory activity of A90 against α-amylase (59.96%), α-glucosidase (54.3%), and maltase (62.73%) was significantly higher than that of A70 (acetone-water, 70:30) and E20 (ethanol-water, 20:80) (p < .05). According to antioxidant activity results, the highest ABTS^•+ (360.5 ± 15.69 μmol Trolox eq per gram of dried GOEs), hydroxyl radical-scavenging activity (3657.75 ± 21.56 μmol histidine eq per gram of dried GOEs), and FRAP assay (558.18 ± 20.26 μmol FeSO₄ eq per gram of dried GOEs) were related to A90, while the best DPPH radical-scavenging activity and metal-chelating activity were related to A70 (302.66 ± 2.42 μmol Trolox equivalents per gram of dried GOEs) and E20 (36.5 ± 1.02 μmol EDTA eq per gram of dried GOEs), respectively. Taken together, A90 appears to be the best solvent to get Galega officinalis extract with the highest antioxidant and antidiabetic activity.