High carbon dioxide and low oxygen storage effects on reactive oxygen species metabolism in Pleurotus eryngii

• The optimized condition was 2% O2 + 30% CO2 at 20–25 °C and 90–95% relative humidity.
• The optimized condition maintained good sensory characteristics of mushrooms.
• The optimized condition alleviated lipid peroxidation in mushrooms.
• The optimized condition limited ROS accumulation in mushrooms.

This study addressed the influence of high carbon dioxide and low oxygen levels on Pleurotus eryngii samples, stored at 20–25 °C and 90–95% RH for 5 d. Evaluations of sensory characteristics, malondialdehyde (MDA) content, superoxide anion (O2−) production rate and the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and cytochrome c oxidase (CCO) were made in the mushrooms in response to high carbon dioxide and low oxygen treatments. The results showed that 2% O2 + 30% CO2 significantly prolonged mushroom shelf-life when compared to the control. The 2% O2 + 30% CO2 mixture was better suited to maintaining mushroom sensory characteristics and delaying the MDA increase and O2− production rate during storage. The activities of SOD, POD, and CAT in 2% O2 + 30% CO2-treated mushrooms were significantly higher than those of the control. However, the CCO activity was not affected by the atmospheric treatment (2% O2 + 30% CO2). These results indicated that the 2% O2 + 30% CO2 treatment could alleviate lipid peroxidation and enhance antioxidant enzyme activities, but it exerted little influence on the CCO activity of Pleurotus eryngii.