XANTHINE-OXIDASE INHIBITORY ACTIVITY OF SOME PANAMANIAN PLANTS FROM CELASTRACEAE AND LAMIACEAE

Thirty four crude extracts of Panamanian plants, from nine species of Celastraceae and Lamiaceae, were assayed for xanthine oxidase (XO) inh ibitory activity. The enzymatic activity was estimated by measuring th e increase in absorbance at 290 nm due to uric acid formation. Eighty five percent of the crude extracts were found to possess XO inhibitory activity at 50 mu g/ml and all the extracts of the species from Lamia ceae were active even at 1 mu g/ml. The ethanol extracts of Hyptis obt usiflora Presl ex Benth. (Lamiaceae) and H. lantanaefolia Poit. (Lamia ceae) exhibited the highest activity with an inhibition of approximate ly 40% at 1 mu g/ml.