Phytochemistry and Anti-Ulcerogenic Effects of the Ethanol Extract of Psidium guajava on Indomethacin- Induced Ulcer in Wistar Rats

Abstract

Background: Psidium guajava leaves are traditionally used for gastrointestinal conditions and may contain bioactive constituents relevant to gastric mucosal protection. This study evaluated the nutritional composition, phytochemical constituents and anti-ulcerogenic activity of the ethanol leaf extract of P. guajava in indomethacin-induced gastric ulceration in Wistar rats. Methods: Fresh guava leaves were collected, air-dried, pulverised and extracted with 70% ethanol. Proximate, vitamin, mineral and quantitative phytochemical analyses were performed using standard analytical methods. Twenty-five male Wistar rats were allocated to five groups (n = 5). Gastric ulceration was induced with indomethacin (30 mg/kg). The standard control group received cimetidine (11.4 mg/kg), while treatment groups received the extract at 100, 200 or 400 mg/kg. Gastric volume, gastric pH, ulcer index and protection index were assessed, and data were analysed using ANOVA with significance set at p < 0.05. Results: The leaves contained carbohydrate, protein, fat, fibre, vitamin C and vitamin A. Phytochemical analysis showed alkaloids, saponins, tannins, flavonoids, cardiac glycosides and phenols. Extract treatment reduced the ulcer index from 24.70 ± 10.30 in the negative control to 12.60 ± 2.80, 11.10 ± 3.00 and 8.90 ± 2.20 at 100, 200 and 400 mg/kg, respectively. The highest extract dose produced a protection index of 63.97%, close to cimetidine. Conclusion: The findings suggest that ethanol extract of P. guajava leaves has dose-related anti-ulcerogenic activity in this model, alongside measurable nutritional and phytochemical constituents.