Antioxidant and antidiabetic properties of <i>Tetrapleura tetraptera</i> (Schum. and Thonn.) Taub. whole fruit

Abstract

The objective of this study is to investigate toxicity, phytochemical constituents, antioxidant and antidiabetic activities of Tetrapleura tetraptera whole fruits. Phytochemical screening of the extract identified the presence of alkaloid, saponin and flavonoid. The total phenolic contents of methanol extract, hexane, chloroform and ethyl acetate fractions are of 38.63 ± 8.11, 52.41 ± 1.92, 8.16 ± 0.36 and 5.16 ± 0.56 mg gallic acid equivalent/g of extract, respectively, while methanol extract, hexane, chloroform and ethyl acetate fractions had total flavonoid contents of 6.87 ± 0.81, 7.44 ± 0.78, 12.38 ± 0.72 and 9.32 ± 0.37 mg quercetin equivalent/g of extract, respectively. The IC₅₀ for DPPH radical scavenging activity of methanol extract, hexane, chloroform and ethyl acetate fractions are 192±2.01, 226.67±1.40, 73.33±1.86 and 127.33±3.18μg/mL respectively. The IC₅₀ value of ascorbic acid was 18.44±1.20 μg/mL. The methanol extract of T. tetraptera fruit (1g/kg bw.) produced a significant (p<0.05) reduction of fasting blood glucose level. There was an increase in the plasma level of ALT in T. tetraptera treated rats compared to the control. According to histopathological examinations of the pancreas of diabetic rats given methanol extract treatment, the pancreatic islets' size was noticeably reduced, the islets of Langerhans' outlines were atypical, and there were numerous hemorrhages throughout the organ. These results indicate that the fruit of T. tetraptera may be a source for future oral hypoglycemic drug development.