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The polyphenol oxidase (PPO) enzyme was purified and characterized from Hemşin Apple (Malus communisL.), which was organically grown in Hemşin, in the Rize province of Turkey. Enzyme (PPO) activation was determined with catechol substrate. Apples were homogenized with homogenate buffer (pH 8.5). This process was followed by precipitation with (20–80%) saturated solid (NH4)2SO4and dialysis. Finally, purification with DE52-Cellulose ion-exchange and Sephadex G-25 columns was performed. Experiments were performed at an optimum pH (5.5) and optimum temperature (30–40°C). The kinetic and thermal parametersKm (3.40 mM),Vmax (333.3 EU/mL.min),Ea(3.57 kcal), ∆H (2.968 kcal/mol), Q10(1.33),kcat(24.57 min−1) andV0(7.2x103mM−1.min−1) were assessed. Additionally, the effects of Mg2+, Pb2+, Fe2+, Fe3+, Cd2+, Cu2+, Zn2+, Co2+, Al3+, Mn2+and Na+on enzyme activity was recorded, and the IC50values, Kİvalues and inhibition types were determined. [ABSTRACT FROM AUTHOR]