In vitro screening of extracts for their xanthine oxidase inhibitory potential of some Indian medicinal plants and active fraction of selected plants

Abstract

Background: The activity of xanthine oxidase (XO) enzyme plays main role in the induction of hyperuricemia, gout and raising superoxide radical level in blood through oxidation of xanthine and hypoxanthine into uric acid. Thus, inhibition of xanthine oxidase activity is regarded as an effective treatment of hyperuricemia, gout, inflammation and other XO associated diseases.

Objective: Twenty- seven plants extracts were assayed for the novel XO inhibitors to develop a potent lead for the management of hyperuricemia gout, and other XO metabolism related diseases / disorders.

Materials and methods: Traditional knowledge based prioritized plant extracts were screened for XO inhibitory potential through in-vitro assay. Microtiter plate based high through spectrophotometric method was employed to determine the inhibition by measuring the uric acid at 295 nm.

Results: The in-vitro assay of extracts was found as eight alcoholic and six hydroalcoholic extract found to have highest inhibition more than 50% at a concentration of 250 μg/ml in the assay mixture. While thirteen plant extracts found to have moderate inhibition 20-30% at 250 µg/ml. Plants Alectra chitrakutensis, Butea monosperma, Dasmodium gangeticum, Gardenia lucida, Zanthoxylum armatum investigated their IC₅₀ values below 250 μg/ml.

Conclusion: On the basis of detail phytochemical exploration both from data mining and 3qualitative evaluation, we found that phenolic rich plants particularly Z. armatum and G. lucida showed highest XOI potential. Present study correlates with the traditional usages of these plants and provides basis for further investigation for lead of natural XOI for treatment of gout and other XO-related disorders.