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Published on: April 26, 2016
Enzyme activity of alpha-chymotrypsin after derivatization with phenolic compounds
Sascha Rohn1, Harshadrai M Rawel, Ulla Wollenberger
1University of Potsdam, Institute of Nutritional Science, Bergholz-Rehbrücke, Germany.
Abstract:
Alpha-chymotrypsin was allowed to react with selected phenolic and related compounds (chlorogenic acid, m-, o-, p-dihydroxybenzene, p-benzoquinone). The derivatized enzymes obtained were characterized in terms of their activity. In vitro experiments illustrated that the enzymatic activity of the derivatives was adversely affected. The kinetics of the enzymatic reactions showed that the hydrolysis of selected food proteins becomes slower and the affinity of the enzyme to these substrates declined as measured by Michaelis-Menten constant and maximum velocity of the enzymatic reaction. This enzyme inhibition depended on the reactivity of the phenolic and related substances tested as well as on the degree of the derivatization. Further, influence of the enzyme-substrate ratio was also demonstrated. The effects of the derivatization are more pronounced with increasing concentration of the substrates.
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