Biological and phytochemical investigations of crude extracts of Astragalus creticus

Abstract

This study was carried out to isolate the secondary metabolites and to evaluate the antibacterial, antifungal, antioxidant, phytotoxic, anti-leishmanial and α-glucosidase activities of dichloromethane and methanol extracts of whole plant of Astragalus creticus. Preliminary phytochemical screening indicated flavonoids, saponins, tannins and cardiac glycosides in this plant. Phytochemical evaluation of methanol extract resulted in isolation and characterization of Ethyl gallate, 1-triacontanoic acid, quercimeritrin, kaempferol-7-O-β-D-glucopyranose, myricetin, kaempferol, betulinic acid, stigmasterol and Daucosterol. The structures of the compounds were determined by Mass and NMR spectroscopy. The methanol extract exhibited better activity against Staphylococcus aureus (58.75%) while dichloromethane extract was found to be very active against Bacillus subtilis (56.30%).The methanol extract demonstrated highly significant phytotoxic (92.68% at 1000µg/ml) and antioxidant (64.55±0.43%) potential while both extracts identified best inhibition of α-glucosidase enzyme. The plant extracts showed non-significant antifungal and anti-leishmanial activities. To our knowledge, it’s a first research study on Astragalus creticus that indicate a great biological and phytochemical potential in it.