Abstract

This research was carried out on the aqueous extracts of bitter leaf (Vernonia amygdalina) to evaluate its phytochemical, proximate and antioxidant composition and its effects in vivo on diabetes and obesity biomarkers, antioxidant and hematological profiles.The phytochemical screening of the bitter leaf extract showed a high concentration of flavonoids as the most abundant phytochemical present. Daily administration of extract to rats led to a slight decrease in the lipid profile of the test rats relative to control and no significant difference in the liver function, kidney function, glucose level and hematological profile of test rats relative to control. Antioxidant assay showed high levels of total antioxidant activity and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity that was concentration dependent. In vivo antioxidant enzyme assay showed an appreciable increase in the level of the antioxidants, glutathione (GSH), superoxide dismutase (SOD), catalase and malondialdehyde (MDA) of the test rats as compared to control. This suggests improved functionality of the antioxidant system of the test rats probably due to the effect of the phytochemical antioxidants in the extract. It is concluded that aqueous extract of V. amygdalina can be consumed as food or as an herbal medicine without plausible toxicity to body organs and tissues.

Key words: Bitter leaf, medicinal plants, lipid profile, hematology, antioxidants.