LAUSR

ABSTRACT This study investigated the effect of hypobaric treatment on the fruit quality, bioactive compound contents, and reactive oxygen species (ROS) metabolism of blueberry. Blueberry fruit cv. bluecrop were stored under hypobaric pressures of 0.025, 0.05, 0.075 and 0.1 MPa (control) at 20°C for 25 and 50 d, respectively. Fruit physiological changes, bioactive compound contents, pro- and anti-oxidant enzyme activities and antioxidant capacities were monitored. Results showed that hypobaric treatment had little influence on decay rate, firmness, respiratory rate, pH and soluble solid content (SSC). However, the contents of bioactive compounds such as anthocyanins, total phenols, and total flavonoids increased significantly, especially at 0.025 MPa. The effect of hypobaric storage on the bioactive compounds of blueberries was through (i) promoting ROS degradation through catalase (CAT), (ii) reducing ROS and bioactive compounds degradation by polyphenol oxidase (PPO) and peroxidase (POD), (iii) increasing the ROS scavenging and antioxidant capacity of blueberries. Graphical abstract