In vitro antioxidant, antiglycation, α-glucosidase and α-amylase inhibitory activities of extracts and solvent fractions of Elaeocarpus serratus L.

Plants are an essential source of unique pharmacologically active natural products beneficial to human and animal health. In this research, crude extracts and solvent fractions from the leaves, bark, stem, seeds and fruit pulp of Elaeocarpus serratus (Cylon olive) were assessed for their antioxidant potential, antiglycation and enzymatic inhibitory activity. Phytochemical contents were analyzed by the colorimetric method. Antioxidant activities were estimated by DPPH radical scavenging, superoxide anion radical and ferrous ion chelating assays. Antiglycation properties were determined through the bovine serum albumin-methylglyoxal (BSA-MG) test and enzyme inhibitory activities were tested in vitro on α-glucosidase and α-amylase. The ethyl acetate fraction of the leaves exhibited high phenolic content (71.63 ± 0.01 mg GAE/g DW). The n-butanol fraction of the bark had high flavonoid content (37.37 ± 0.07 mg QE/g DW). The n-butanol fraction of the bark also significantly inhibited both α-glucosidase and α-amylase with IC50 values of 2.32 ± 0.62, and 2.81 ± 0.37 μg/mL, respectively, compared with quercetin (43.27 ± 3.24 μg/mL) and acarbose (17.72 ± 2.35 μg/mL). These findings indicate that E. serratus can be a source of plant-based pharmaceuticals and natural products, which may be considered for the treatment of diabetes and the formulation of healthy food supplements. However, further studies are required on the isolation, identification and toxicity of components from E. serratus.