• Maja Marasović University of Split
  • Zrinka Čorić University of Split
  • Mladen Miloš University of Split
  • Borivoj Galić University of Split
Keywords: Tyrosinase inhibitors, kojic acid, boronic acids, halogenated boroxine dipotassium-trioxohydroxytetrafluorotriborate.


INTRODUCTION: A number of biochemical and medical researchers have detected increased activity of tyrosinase in skin tumor cells. The most famous and available inhibitor, kojic acid, has several side effects and is not completely safe for use.

OBJECTIVES: This paper describes the study of inhibitory influence of halogen boroxine K2[B303F4OH] on tyrosinase. The research was prompted by the ability of this compound to inhibit enzymes through metal ion chelation as well as its synthesis and application in cosmetic skin products that produce no serious side-effects.

METHOD: Tyrosinase activity was measured by spectrophotometric analysis for the appearance of dopachrome pigment at a wavelength of 475 nm. Tyrosinase exhibited typical Michaelis-Menten kinetics.

RESULTS: Tests of the proposed inhibition of the enzyme tyrosinase showed that K2[B3O3F4OH] had weak inhibitory properties.

CONCLUSION: It will be necessary to search for new ways of antitumor mechanisms that differ from those of previous results.


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