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草菇多酚氧化酶(polyphenoloxidase)与过氧化物酶(peroxidase)的最适pH分别为60~68、67~74,最适温度分别为30~32℃、25~28℃在最适条件下,前者的活性远高于后者,当pH86及温度43℃或48℃处理1min,二者活力显著降低;但是,先在35~38℃保温1h再测定,发现二者的最适温度分别达40~41℃、52~53℃,升温至80℃10s,过氧化物酶仍表现活性O2对多酚氧化酶活性影响极大,而对过氧化物酶活性影响较小金属离子Mn2+、Zn2+、Mg2+对二者均有强烈激活作用,Ca2+对二者的作用都很弱,Fe2+、Cu2+对前者作用明显强于后者二者的反应进程及酶浓度与反应速度的关系,表现出较大的差异
The optimal pH values of polyphenoloxidase and peroxidase were 60 ~ 68, 67 ~ 74, respectively, and the optimum temperature were 30 ~ 32 ℃, 25 ~ 28 ℃ under the optimum conditions, the former activity is much higher than the latter, when pH8 6 and temperature 43 ℃ or 48 ℃ for 1min, both significantly reduced vitality; however, the first 35 ~ 38 ℃ incubated 1h and then The results showed that the optimum temperature of the two was 40 ~ 41 ℃, 52 ~ 53 ℃, respectively. When the temperature was raised to 80 ℃ for 10 seconds, the activity of peroxidase still had a great influence on the activity of polyphenol oxidase, The activity of enzyme was less affected. Mn2 +, Zn2 + and Mg2 + were strongly activated by both metal ions. The effect of Ca2 + on both was weak. The effect of Fe2 + and Cu2 + on the former was stronger than that of the latter And the relationship between enzyme concentration and reaction rate, showing a greater difference