In Vitro Inhibition of Rumen Urease by Melon (Cucumis melo) Seed Urease Inhibitor

Abstract

The urease (urea aminohydrolase; EC. 3.5.1.5) inhibitor isolated from Cucumis melo seeds decreased the urease activity of intact rumen microbes in vitro. Inhibition was 50% at a inhibitor concentration of 3.0 mg/ml. The kinetics of inhibition with partially purified rumen urease (21-fold) was noncompetitive in nature with inhibitor constants .67 and .95 mg/ml at 39 C and 30 C. The inhibitor appeared to be slightly susceptible to hydrolysis by pepsin, trypsin, or rumen proteases. © 1980, American Dairy Science Association. All rights reserved.