Inhibitory effects of Cefazolin and Cefodizime on the activity of mushroom tyrosinase

Abstract

Tyrosinase (EC 1.14.18.1) catalyzes both the hydroxylation of tyrosine into o-diphenols and the oxidation of o-diphenols into o-quinones that form brown or black pigments. In the present paper, the effects of Cefazolin and Cefodizime on the activity of mushroom tyrosniase have been studied. The results showed that the Cephalosporin antibacterial drugs (Cefazolin and Cefodizime) could inhibit both monophenolase activity and diphenolase activity of the enzyme. For the monophenolase activity, Both Cefazolin and Cefodizime could lengthen the lag time and decrease the steady-state activities, and the IC₅₀ values were estimated as 7.0 mM and 0.13 mM for monophenolase activity, respectively. For the diphenolase activity, the inhibitory capacity of Cefodizime was obviously stronger than that of Cefazolin, and the IC₅₀ values were estimated as 0.02 mM and 0.21 mM, respectively. Kinetic analyses showed that inhibition by both compounds was reversible and their mechanisms were competitive and mixed-type, respectively. Their inhibition constants were also determined and compared. The research may offer a lead for designing and synthesizing novel and effective tyrosinase inhibitors and also under the application field of Cephalosporins.

Keywords::

• Tyrosinase
• monophenolase activity
• diphenolase activity
• Cefazolin
• Cefodizime
• inhibition kinetics

Acknowledgements

The present investigation was supported by Grant 30570408 of the Natural Science Foundation of China, Grant 2007N0051 of the Science and Technology Foundation of Fujian Province and by the Program for Innovative Research Team in Science and Technology in Fujian Province University.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.