Synergistic effect of 1-methylcyclopropene and carvacrol on preservation of red pitaya (Hylocereus polyrhizus).

Pitaya fruit is susceptible to fungal attack and shrivelling during storage. This study investigated the individual and combined effect of 1-methylcyclopropene (1-MCP) and carvacrol (CVR) on red pitaya. Fruits were treated with 1 µL L-1 1-MCP, 20 µL L-1 CVR or their combination (1-MCP + CVR), and then storage at 7 °C for 30 days. 1-MCP + CVR was more effective in suppressing decay and maintaining quality during storage than individual treatment of 1-MCP or CVR. In addition, 1-MCP + CVR treatment led to decreased levels of O2-, H2O2, and lipid peroxidation, concomitant with increased activities of superoxide dismutase, catalase, and ascorbate peroxidase, and elevated total phenolic content, as compared to the individual application. Moreover, transmission electron microscopy observation showed that the combined treatment protected cell ultrastructure from oxidative damage. This study suggests 1-MCP combined with CVR may be a useful method for the preservation of pitaya fruit.