Phytochemical Screening, Antioxidant, and Antidiabetic Activities of Different Solvent Extracts of Elaeocarpus serratus (Veralu) and Elaeocarpus angustifolius (Nilveralu) Grown in Sri Lanka

Abstract

The novel bioactive compounds derived from plants have shown more efficacy in the management of type II diabetes. The dried fruit pericarp of Elaeocarpus serratus and Elaeocarpus angustifolius were extracted with methanol, hexane, ethyl acetate, and aqueous using sonication extraction. The antioxidant activities were determined through the DPPH and ABTS radical scavenging assays, ferric reducing power (FRAP), and oxygen radical absorbance capacity (ORAC) methods. The anti-diabetic activities were assessed using anti-amylase and anti glucosidase assays. The crude extract of E. serratus had the highest total phenolic content (561.47 ± 28.35 mg GAE/g of dried extract), while the ethyl acetate fraction of E. angustifolius had the highest total flavonoid content (0.19 ± 0.00 mg QE/g of dried extract). The highest ORAC, FRAP, DPPH, and ABTS values were in the aqueous fraction of E. serratus (83.35 ± 5.20 mg TE/g of dried extract), crude of E. serratus (668.75 ± 7.7 mg TE/g of dried extract), aqueous fraction of E. serratus (89.23 ± 2.92 mg TE/g of dried extract), and hexane fraction of E. serratus (570.305 ± 7.067 mg TE/g of dried extract), respectively. The results showed that all four extracts of E. serratus had significantly (p<0.05) high amounts of antioxidants. Aqueous and crude extracts of E. angustifolius showed the highest anti-glucosidase activities (IC50 = 44.58 ± 0.17 µg/mL, 248.50 ± 0.18 µg/mL, respectively) compared to Acarbose (IC50 = 262.32 ± 0.69 µg/mL). None of the extracts showed anti-amylase activities. These findings conclude the potential of these fruits to enhance and promote their commercial value.