The present work was designed to study the chemical composition, antioxidant, antihyperglycemic effect, and toxicity assessment of Ridolfia segetum (L.) Moris extract. The chemical composition was studied by use of high-performance liquid chromatography (HPLC). Antioxidant power was tested by use of DPPH and FRAP assays. The antihyperglycemic effect was tested by use of a glucose tolerance test, while toxicity assessment was done in vivo by use of Wistar rats for 14 days. Analysis of the extract by HPLC-UV revealed the presence of gallic acid, catechol, vanillic acid, catechin, tannic acid, rosmarinic acid, naringenin, and coumarin acid. The crude hydroethanolic extract possessed high levels of total phenols (15.6 ± 1.76 mg EAG/g), condensed tannins (383.49 mg ECat/g DM), and flavonoid (11.63 mg EQ/g). The findings showed that the studied extract possessed good antioxidant power with IC50 values equal to 550, 650, 700 µg/mL respectively for the decoction, the ethyl acetate fraction (F2M), and the ethyl acetate fraction (F2E). For the antioxidant activity by FRAP, the aqueous fraction (F3E) and the aqueous extract (F4) showed CE50 values of 0.33 mg/mL and 0.4 mg/mL, respectively. Glucose tolerance test analysis showed that R. segetum (L.) Moris decoction had a significant postprandial antihyperglycemic effect in normal Wistar rats. The results of the acute toxicity test showed that the decoction was not toxic even at 2 g/Kg. Pancreatic α-amylase activity was significantly inhibited in the presence of R. segetum (L.) Moris extract (IC50 = 0.133 ± 0.09 mg/mL). The outcome of the present work showed that R. segetum (L.) Moris is very rich in phenolic compounds with potent antioxidant and antihyperglycemic effects.
Keywords: DPPH; FRAP; Ridolfia segetum (L.) Moris; antihyperglycemic; polyphenols; toxicity.