Comparison of polyphenol oxidase in fruits of Solanum melongena L. (purple) and Solanum melongena L. (green)

A comparative study of polyphenol oxidase (PPO) from two varieties of brinjal (local long green-bili badnea and purple-gundu badne) was conducted to determine differences and similarities of some of the characteristics of the PPO enzymes in terms of temperature and pH optima, substrate specificity, thermal inactivation and potency of some PPO inhibitors. PPO was partially purified by ammonium sulfate precipitation followed by dialysis. The optimum pH and temperature of the two PPOs was found to be similar. It is found that the PPO activity is found more in local long green-bili badnea than in purple-gundu badne. PPO activity is almost double the concentration in local long green-bili badnea compared to PPO found in purple-gundu badne. The data obtained in this study help to better understand fruit browning in two varieties of brinjal.