双孢蘑菇易褐变菌株的多酚氧化酶特征

The Polyphenol Oxidase Characteristics of Easy-Browning Agaricus bisporus Strains

采用凝胶电泳等生化技术探讨了蘑菇易褐变菌株的酚酶特征。发现易褐变菌株具有特异的同工酶表型,子实体阶段表达的酚酶位点多,且酶活性高;其整个生活史的胞内酚酶活性曲线变化与优质菌株不同;所表达的酚酶对亚硫酸盐类酚酶抑制剂的敏感性低;所表达的酚酶较耐热,在加热的初始阶段(35～40℃)就能迅速催化褐变反应;所含的潜伏型酚酶含量大,且随着鲜菇贮藏期延长而大量活化,继续催化褐变。本文还就如何防止褐变进行了探讨。

The polyphenol oxidase (PPO) characteristics of easy-browning A. bisporus strains were investigated using biochemical technology such as AGE etc. The results showed that the easy-browning strains were possessed of special PPO isozyme pattern and more PPO loci with high enzyme activity at fruitbody growing stage, that the changes of the endocellular PPO activity curve of easy-browning strains were different from that of the high-quality strains during its whole life cycle, that its PPO sensitivity to the PPO inhibitor such as Na2SO3 was relatively low, that its PPO which was tolerant to heat could swiftly catalyze the browning reaction during the initial stage of heat-ing(35-40℃) and that its content of latent PPO was great and the latent PPO was activated in great amount with the extending of storage time to continue catalyzing the browning reaction. And the control of the browning was also discussed in this paper.