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南果梨果肉中多酚氧化酶（PPO）氧化邻苯二酚的活性明显高于氧化愈创木酚和间苯二酚的活性。以邻苯二酚为底物时，其多酚氧化酶的最适pH值为6．0。以儿茶酚为底物的多酚氧化酶氧化产物在420nm处有吸收高峰。聚乙烯吡咯烷酮（PVP）加入量与南果梨果肉酚类含量比为40：3时，南果梨果肉多酚氧化酶呈最大活性。30℃下多酚氧化酶的活性大于40℃、20℃、10℃、0℃下以儿茶酚为底物的南果梨果肉的多酚氧化酶活性。0．1MVc和001MEDTA对南果梨果肉的多酚氧化酶活性有明显抑制作用。根据凝胶电泳分析，南果梨果肉多酚氧化酶同功酶有8条谱带。
The activity of polyphenol oxidase (PPO) oxidized catechin in Nanguo pear pulp was significantly higher than that of oxidized guaiacol and resorcinol. With catechol as substrate, the optimum pH of polyphenol oxidase was 6.0. Polyphenol oxidase oxidation products with catechol as substrates have absorption peaks at 420 nm. Polyvinylpyrrolidone (PVP) and Nanguo pear pulp phenolic content ratio of 40: 3, Nanguo pear pulp polyphenol oxidase activity was the most. The activity of polyphenol oxidase at 30 ℃ was higher than polyphenol oxidase activity of Nanguo pear pulp at 40 ℃, 20 ℃, 10 ℃, 0 ℃ with catechin as substrate. 0.1MVc and 001MEDTA significantly inhibited the polyphenol oxidase activity of Nanguo pear pulp. According to gel electrophoresis analysis, Nanguo pear pulp polyphenol oxidase isozyme has 8 bands.