Abstract: In this paper, changes in the contents of chitin, cellulose and lignin in Agaricus bisporus during high-oxygen dynamic controlled atmosphere (HO-DCA) storage were examined as well as changes in cell wall metabolism and enzyme activities related to lignin synthesis. The results showed that the chitin content of HO-DCA treated Agaricus bisporus was significantly higher than that of the static-controlled atmosphere and control groups at the end of storage (P < 0.05), and chitinase activity was significantly lower than the control group (P < 0.05), indicating that HO-DCA treatment effectively inhibited the degradation of chitin in the cell wall. Meanwhile, HO-DCA treatment significantly inhibited cellulase activity (P < 0.05) and maintained a higher content of cellulose, thus maintaining a higher tissue compressive resistance. At the late stage of storage, the lignin content of the stipe increased dramatically, and the degree of lignification was improved; the degree of lignification was greater in the stipe than in the pileus. The activities of 4-coumarate: coenzyme A ligase (4CL) and cinnamyl alcohol dehydrogenase (CAD) were positively correlated with lignin content, while there was no significant correlation between phenylalnine ammonialyase and lignin content. The lignin content of HO-DCA treated Agaricus bisporus was significantly lower than that of the control (P < 0.05), indicating that HO-DCA treatment inhibited lignin accumulation by inhibiting the activity of 4CL and CAD in Agaricus bisporus and delayed its lignification. The results of this study can provide a theoretical basis for effectively controlling texture deterioration of Agaricus bisporus.

Key words: Agaricus bisporus, high-oxygen, dynamic controlled atmosphere, cell wall, lignin