Investigation of the effects of pesticides on 'Jonagold' apple (Malus x domestica) polyphenol oxidase enzyme activity

this study, the effects of a number commonly used pesticides on activity polyphenol oxidase (PPO) enzyme from pesticide-free and pesticide-applied 'Jonagold' apples were comparatively evaluated. Substrates 4-methylcatechol, pyrocatechol, pyrogallol L-tyrosine to determine substrate specificity PPO obtained apple. According results, contrary, apple did not show any against which is monophenolic substrate, had high affinity pyrocatechol are di tri phenolic substrates. Km values substrates determined as followed 0.27 mM, 2.27 0.37 respectively. Vmax found 0.133 mM/min, 0.081 0.051 mM/min. Optimum pH be 4.5 for 7.0 7.5 pyrogallol. temperature 40 °C 10 50 pesticide-treated 0.98 3.94 0.08 0.02 0.034 4-methylcatechol 30 Overall, results showed that higher than apples. The metals storage stability also investigated. reveal pesticide use affects activity. data bring light new functional features great interest in medicinal, agro-chemical environmental circles.