Why do you think the enzyme(PPO) activity is dropping with time? Is benzoquinone a reactive species?...

Why do you think the enzyme(PPO) activity is dropping with time? Is benzoquinone a reactive species?

ppo=polyphenol oxidase

the question comes from enzymatic browning reaction.

Expert Solution

The enzyme polyphenol oxidase (PPO) catalyzes the oxidation of phenolic compounds into highly reactive quinones. Polymerization of PPO-derived quinones causes the postharvest browning of cut or bruised fruit, but the native physiological functions of PPOs in undamaged, intact plant cells are not well understood.

PPO activity is most commonly measured by spectrophotometric assay, in which the rate of phytomelanin production is quantified, or by oxygen electrode assay, in which the consumption of oxygen by the enzyme is quantifiedPPO activity is most commonly measured by spectrophotometric assay, in which the rate of phytomelanin production is quantified, or by oxygen electrode assay, in which the consumption of oxygen by the enzyme is quantifiedPPO activity is most commonly measured by spectrophotometric assay, in which the rate of phytomelanin production is quantified, or by oxygen electrode assay, in which the consumption of oxygen by the enzyme is quantified.

Thank you, hope this answer will help.

queen_honey_blossom answered 2 years ago

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