EFFECTS OF PHENOLICS COMPOUNDS ON SOYBEAN UREASE ACTIVITY

Allelopathy is defined as any direct or indirect harmful effect of one plant (including microorganisms) on another through the production of chemical compounds that escape into the environment. The allelochemic als produced by microorganisms or higher plants include p-coumaric and ferulic acids: these phenolic compounds were found in soils at concen trations between 0,01 mM and 0,1 mM. Soybean urease (E.C. 3.5.1.5) cat alyzes the hydrolysis of urea, thus producing carbon dioxide and ammon ia which are important for plant growth. This article analyzes a proba ble relation between allelopathic agents and enzymatic activity of ure ase. The results show that p-coumaric acid is an inhibitor of urease a t high concentrations (10 mM), while ferulic acid inhibits the enzyme at extremely low concentrations (10(-7) mM).