Tyrosinase, the enzyme responsible for biosynthesis of melani pigments has a special place. It is a metaloenzyme containing copper ions that catalyses two distinct reactions in the pathway of melanin biosynthesis. The monophenolase activity leads to hydroxylation of phe
More
Tyrosinase, the enzyme responsible for biosynthesis of melani pigments has a special place. It is a metaloenzyme containing copper ions that catalyses two distinct reactions in the pathway of melanin biosynthesis. The monophenolase activity leads to hydroxylation of phenylalanin and the oxidation of 3, 4 dihydroxy phenylalanin to O-dopaquinon is through its diphenolase activity. Inhibitors and activators of the enzyme has a wide variety of effects on human health as well as in industrial applications. Considering the importance of pigments in human skin and hair and the role of tyrosinase in the production of melanin pigments, in the present research three important skin medications were selected for their effect on tyrosinase activity. In practical section, the enzyme was first extracted from banana skin followed by its characterization. The kinetic parameters were then investigated in the presence and absence of benzocaein, zinc oxide and kojic acid and the Michaelis Menton as well as Linweaver Burk plots were obtained. The results indicated that tyrosinase extracted from banana skin is similar to mushroom tyrosinase and its optimum temperature is higher than known tyrosinases. Therefore, by bearing in mind its low priced source, it can be recommended as an alternative to the commercial enzyme from mushroom. The results also showed that all three medicines were un-competitive inhibitors of tyrosinase. They reduced the maximum rate, Vmax of enzymatic reaction with no effect on Km. The highest inhibitory activity was obtained for zinc oxide Keywords: Tyrosinase, banana wastes, benzocaein, kojic acid, zinc oxide
Manuscript profile
