Optimum temperature of polyphenoloxidase

The optimum temperature for the enzyme polyphenol oxidase (PPO) is 40 degrees Celsius. This is the temperature at which the enzyme is most effective; like many other enzymes the rate of reaction will decrease with temperature, but if the temperature rises much above the optimum level, it will cause the enzymes to denature. Denatured enzymes will stay denatured even if the temperature decreases again. The optimum pH for polyphenol oxidase is 5.