ANTIOXIDANT PROPERTIES OF AQUEOUS STEM BARK EXTRACT OF ANOGEISSUS LEIOCARPUS AGAINST ETHANOL-INDUCED GASTRIC ULCER IN RATS
The Gastroprotective effect of aqueous stem bark extract of Anogeissus leiocarpus against ethanol induced gastric ulcer in albino rats was investigated. Eighty-six albino rats (weighing 160-250g) of both sexes were used in this study. The results of the qualitative analysis of phytochemical constituents of aqueous stem bark extract of Anogeissus leiocarpus shows the degree of abundance of these phytochemicals in mg/100g of the extract is as follows; 87.67 of flavonoids, 51.00 of alkaloids, 36.33 of saponins, 11.23 of tannin, and 15.53 of phenol. The oxidative analysis shows significant decrease in Malondialdehyde (MDA) at 100mg/kg, 200mg and 400mg/kg b.w as well as the (100mg/kg b.w) cimetidine group (p˂0.05) when compared with the ulcer control group. Antioxidant studies shows a significant increase in Catalase at 100mg/kg, 200mg/kg and 400mg/kg b.w groups as well as 100mg/kg cimetidine group (p˂0.05) when compared with the ulcer control group. There was a significant increase in Superoxide dismutase (SOD), at 400mg/kg b.w and 100mg/kg cimetidine groups when compared with the ulcer control group. In Glutathione Peroxidase (GPx), there was a significant increase in 400mg/kg b.w group (p<0.05) but there was no significance increase in 100 and 200mg/kg as well as (100mg/kg) cimetidine group (p 0.05) when compared with the ulcer control group. . The aqueous extract of A. leiocarpus was partially purified by column chromatography. Eluents with similar Rf values were pooled together into five fractions using thin layer chromatography (TLC). The qualitative (spectrophotometrically using DPPH) and quantitative antioxidant activity of the five pooled fractions were determined to using 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) spray to identify the fraction with highest activity on a TLC plate, an active spot turned from violet to yellow. Fraction A had higher DPPH percentage inhibition of (97.95%) and the lowest IC50 (20.88). In conclusion these findings suggest that aqueous stem bark extract of A. leiocarpus possesses antioxidant properties and dose-dependent gastroprotection, these justify the ethno medicinal use of the plant in the treatment and management of gastric ulcer.