ANTIOXIDANT AND ANTIDIABETIC EFFECTS OF VERNONIA AMYGDALINA DEL. ETHANOLIC LEAF EXTRACT ON DROSOPHILA MELANOGASTER

Abstract

Diabetes mellitus (DM) is a significant global public health concern. Vernonia amygdalina Del. is a medicinal herb reported to have multiple biological activities, including antidiabetic properties. This work investigated the in vitro and in vivo antioxidant and antidiabetic properties of Vernonia amygdalina Del. ethanolic leaf extract (VAE). Total phenolic content (TPC) and total flavonoid (TFC) content of VAE were assessed using Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. The antioxidant activities of VAE were assessed by the DPPH and FRAP methods. The effects of the VAE on the gustatory, toxicity, body weight, and triglycerides were determined in wild-type Drosophila melanogaster. The results showed that VAE had high levels of TPC (57.45±0.45 mg GAE/g DW), TFC 79.55±0.88 mg QE/g DW), and in vitro antioxidant activities (0.11±0.02 mg/mL).VAE exhibited the in vitro inhibitory activities against α-glucosidase and α-amylase with the IC50 values of 267.69±11.51 µg mL-1 and 331.56±26.47 µg mL-1. Treatment with VAE at 5 and 15 mg/mL did not affect the fruit fly survival, indicating that VAE was not toxic to the insects. In D. melanogaster supplemented with 15 mg/mL VAE, significant increases in survival time after exposure to H2O2 and paraquat were observed. VAE also reduced triglyceride levels in fruit flies fed with a high-sugar diet. These findings suggest that VAE, which is derived from natural sources, possesses antioxidant and antidiabetic properties and may also be used as a potential source of bioactive compounds for managing hyperglycemia.