STUDY ON XANTHINE OXIDASE INHIBITORY ACTIVITY OF Hygrophila auriculata

Background: Gout is a metabolic disorder associated with hyperuricemia and the deposition of urate crystals in joints, Xanthine oxidase plays a key role in the formation of uric acid and is therefore an important therapeutic target for the management of gout. Hygrophila auriculata is a medicinal plant containing various bioactive phytoconstituents which may possess potential pharmacological activities. However, it may contain xanthine oxidase inhibitory activity but it confirms after the investigation Objective: To evaluate the antigout activity in ethanolic extract of Hygrophila auriculata. Methods: Dried and powdered leaves of Hygrophila auriculata were extracted with ethanol using a Soxhlet apparatus. Preliminary phytochemical screening was performed on the ethanolic extract. Xanthine oxidase inhibitory activity was evaluated at concentrations of 50, 100, 200, 400, 800 and 1600 µg/ml using xanthine as substrate, with allopurinol as the standard drug. Absorbance was measured at 290 nm using a UV spectrophotometer. The assay was performed in triplicate. Results: The ethanolic extract showed concentration-dependent inhibition of XO activity. The percentage inhibition increased from 37.76 ± 0.23% at 50 µg/ml to 97.59 ± 0.55% at 1600 µg/ml. Allopurinol showed 21.51 ± 0.53% to 92.87 ± 0.53% inhibition over the same concentration range. The IC₅₀ values were 71.71 µg/ml for the H.auriculata extract and 187.84 µg/ml for allopurinol. Conclusion: The present study demonstrated that the ethanolic leaf extract of Hygrophila auriculata possesses concentration-dependent in vitro xanthine oxidase (XO) inhibitory activity. The extract showed increasing inhibition with increasing concentrations, with a maximum inhibition of 97.59 ± 0.55% at 1600 µg/mL. The calculated IC₅₀ value of the ethanolic extract was 71.71 µg/ml under the experimental conditions used in this study