The ultra-low O2 environment after anaerobic treatment enhanced the antioxidant properties of Agaricus bisporus mushroom

Abstract

• Excessive oxidative stress in high O2 environment (19%∼20%)accelerated the quality deterioration of mushrooms. • Ultra-low O2 environment (1%∼2%) improved the antioxidant capacity and reduced oxidative damage. • Ultra-low O2 environment inhibited the browning of mushrooms. • Agaricus bisporus has better anaerobic stress adaptation and hypoxia tolerance. Short-term anaerobic treatment provides significant benefits in maintaining the quality of mushrooms, but this benefit requires re-exposing the mushrooms to a suitable O 2 environment. Hence, this research investigated different re-oxygenation environments after 6 h anaerobic treatment on the antioxidant properties of A. bisporus . Results showed that ultra-low O 2 environment (1%∼2%) reduced the accumulation of superoxide radical (O 2 − ) and hydrogen peroxide (H 2 O 2 ), increased the activity of superoxide dismutase (SOD), catalase (CAT) and aseorbate oxidase (APX) and the content of non-enzymatic antioxidants including flavonoids and ascorbic acid, as well as inhibited browning due to the lowest polyphenol oxidase (PPO) and peroxidase (POD) activities. However, oxidative stress caused by instantaneous high concentration O 2 exposure (19%∼20%) caused severe oxidative damage to tissues and thus showed poor antioxidant properties and color maintenance. In conclusion, the ultra-low O 2 environment after anaerobic treatment can maintain the quality of mushrooms by improving the antioxidant capacity and reducing oxidative damage.