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Updated: May 8, 2026

Quantification of Hypopigmentation Activity In Vitro
Published on: March 6, 2019
Inhibitory kinetics of chlorocinnamic acids on mushroom tyrosinase
Yong-Hua Hu1, Xuan Liu1, Yu-Long Jia1
1State Key Laboratory of Cellular Stress Biology and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China.
Abstract:
Tyrosinase (EC 1.14.18.1) is the key enzyme of most food enzymatic oxidation. Tyrosinase inhibitors are important in food industry. In the present paper, 2-chlorcinnamic acid and 2,4-dichlorocinnamic acid were synthesized and the inhibitory kinetics on mushroom tyrosinase were investigated. The results showed that both compounds synthesized could inhibit tyrosinase activity. For monophenolase activity, both chlorocinnamic acids could extended the lag time and decrease the steady-state activities, 2-chlorcinnamic acid extended the lag time just by 5%, and 2,4-dichlorcinnamic acid extended the lag time more than by 30.4%. For diphenolase activity, the IC50 values of 2-chlorcinnamic acid and 2,4-dichlorocinnamic acid were determined to be 0.765 mM and 0.295 mM, respectively. The inhibition kinetics showed that 2-chlorcinnamic acid and 2,4-dichlorocinnamic acid displayed a reversible and uncompetitive mechanism. The inhibition constants were determined to be 0.348 mM and 0.159 mM, respectively. The research may supply the basis for designing new tyrosinase inhibitors.
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