The Study Of Screening Enzyme Inhibitors By Electrophoretically Mediated Microanalysis Method

The most prevalent diseases which threat people health are found to linked to related enzyme disorders. So the enzyme is one of the most important targets for new drug development. So it is important to develop one fast and lower cost screening enzyme inhibitors method. In this paper, Electrophoretically Mediated Microanalysis(EMMA) method in the research of kinetics of enzyme reactions of a-glucosidase and Tyrosinase were introduced, including the measurement of kinetic parameters of enzyme reactions and screening the inhibitors of a-glucosidase and Tyrosinase and the research of kinetics of inhibitory activities.In the first part of the study of screening a-glucosidase inhibitors, we optimized the reaction condition.40 mM sodium phosphate buffers for the reaction and the incuration time 0 were selected for the experiment. The Michaelis-Menton constant of a-glucosidase and the inhibitive mechanism of acarbose were studied, which were in the same range as previous literature data. Furthermore, the inhibitory ratios of enzymatic activity (IRE) of 20 traditional Chinese drugs were determined. The IRE of Galla Chinensis attained 100%, the inhibitory active are too strong, and may lead to hypoglycemia. The IRE of Flos Caryophylli, Radix et Rhizoma Rhei,Folium Mori, Radix Puerariae, were between 45% and 70%, similar with acarbose, and have potential as a source of a-glucosidase inhibitors.In the second part of the study of screening Tyrosinase inhibitors, we optimized the reaction condition. Deionized water for the reaction and the incuration time 2min were selected for the experiment. With the method, the Michaelis-Menten constant of Tyrosinase and the inhibitive mechanism of Kojic acid (a reference tyrosinase inhibitor) were studied. Furthermore, the inhibitory ratios of enzymatic activity (IRE) of 61 metal complexes and 20 traditional Chinese drugs and some organic compounds were determined. From the result of screening, we find that the 47# have strong inhibitory effect as Kojic acid and the IRE of Fructus Crataegi attained 58.3% and some organic compounds have no inhibitory. A kinetic analysis shows that 47# is a competitive inhibitor for substrates L-tyrosine.