中文摘要：

基于青香蕉组织致密性及多酚氧化酶（PPO）存在形式与成熟香蕉差别较大的特点,以PPO比活力为考察指标,研究缓冲液种类、离子强度、pH值、液料比、聚乙烯聚吡咯烷酮（PVPP）、吐温-80（Tween 80）、浸提时间、提取次数对PPO提取效果的影响.获得壤佳提取工艺条件：0.05 mol/L、pH 6.0的磷酸缓冲液,内含5％的PVPP和1％的Tween 80,液料比1.5∶1（V/W）,10 000 r/min匀浆机打浆20 s,4℃以10 000 r/min离心30 min,残渣重复提取1次,上清液即为粗酶液,酶比活力为1 574.06 U/mg.

英文摘要：

As the tissue density and polyphenol oxidase （PPO） existing forms are greatly different between green banana and ripe banana. In this study, taking the specific activity of PPO as index, effect of some factors including buffer type, ionic strength, pH value, ratio of liquid to solid, PVPP, Tween 80, extraction time, extraction times on the extraction of PPO were studied and the best extraction conditions were 0.05 mol/L pH 6 phosphate buffer containing 5% PVPP and 1% Tween 80, liquid to solid ratio of 1.5：1 （V/W）, homogenization at 10 000 r/min for 20 s, centrifugation at 10 000 r/min for 30 min at 4~C, extraction for two times, as the supernatant was crude enzyme, and the specific activity was 1 574.06 U/mg.