Effect of 24-epibrassinolide treatment on the metabolism of eggplant fruits in relation to development of pulp browning under chilling stress

This study aims to investigate the effect of 24-epibrassinolide (EBR) on the metabolism in relation to development of chilling injury-induced pulp browning of eggplant fruit. The fruits were dipped for 10 min in solutions containing 10 mu mM EBR and then stored at 1 degrees C for 15 days. Chilling injury index, weight loss, electrolyte leakage and malondialdehyde (MDA) content of control fruit increased during storage. Chilling injury improved phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) activities, which are correlated with the increase of total phenolic content and pulp browning of eggplant fruit. The inhibition of pulp browning by EBR treatment was possibly attributed to preserving the cell membrane integrity, reducing total phenolic content, and decreasing PAL, PPO, and POD activities. These results suggest that EBR may inhibit chilling injury and pulp browning in eggplant fruit during cold storage.