RESUMEN
BACKGROUND AND AIM: Bombax buonopozense (Bombacaceae) leaves have been used traditionally for arthritis in south-western Nigeria. Therefore, the aim of the study was to investigate the antioxidant and anti-arthritic activity of B. buonopozense in Complete Freund adjuvant-induce arthritic wistar rats. EXPERIMENTAL PROCEDURE: The plant leaves methanol extract and fractions were screened for preliminary phytochemicals and brine shrimp lethality was determined. Total phenolic content (TPC), Total flavonoid content (TFC) as well as anti-oxidant activity of the extract and fractions were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Cyclophosphamide, gallic acid, and ascorbic acid were used as standards respectively. Anti-arthritic activity of crude methanol extract (BBME) at 100, 200 and 400mg/kg was evaluated in complete Freund's adjuvant (CFA) induced arthritis model in rats. Data were analysed using Graph pad prism version 5, two-way and one-way ANOVA, and Bonferroni post hoc test. RESULTS AND CONCLUSION: Phytochemical screening revealed the presence of flavonoids, alkaloids, and phenolics. The brine shrimp lethality assay of the crude extract and fractions gave LC50 value≥1000µg/mL, compared to Cyclophosphamide (LC50=224.7±0.35µg/mL). The BBME had TPC value of 19.8±0.56mg GAE/g, while the TFC of ethyl acetate fraction was the highest (173.5±0.05mg QE/g). The ethyl acetate fraction has the highest antioxidant activity (IC50=20.96±0.23µg/mL) as compared to ascorbic acid (2.8±0.01) and rutin (20.6±9.26µg/mL). BBME significantly reduced the paw circumference. BBME (400mg/kg) prevented biochemical changes to a greater extent than Celecoxib (20mg/kg). Bombax buonopozense leaves could be an effective antiarthritic and holds prospect in the treatment of rheumatoid arthritis.