Effect of Ozone on the Antioxidant Capacity of "Qiushui" Pear (Pyrus pyrifolia Nakai cv. Qiushui) during Postharvest Storage

The aims of this study are to investigate the effect of different concentrations of ozone (O3) on pear fruit quality. Qiushui Asian pear (Pyrus pyrifoliaNakai cv. Qiushui) were treated with various concentrations of O3 (2.14, 6.42 and 21.4mg/m3) at room temperature everyday for 1h. The pear fruit firmness, superoxide dismutase, catalase, peroxidase (POD), polyphenol oxidase (PPO) activity and the antioxidant composition contents (total phenolics and total flavonoids) were investigated every 8 days. Results indicated that O3 treatment maintained high level of firmness and total soluble solids and also increased the antioxidant enzymes activity of pear fruit during storage. The moderate O3 (6.42mg/m3) treatment could significantly induce higher POD activity, inhibit PPO activity and keep high contents of total phenolics and total flavonoids. These results suggest that postharvest application of suitable O3 treatment (6.42mg/m3) could enhance antioxidant capacity and keep pear fruit quality. Practical Applications The presented study showed that treatment with suitable concentration of O3 (6.42mg/m3) could delay the decrease of fruit quality, induce higher antioxidant enzyme activities, and keep a higher antioxidant capability of the Qiushui pear fruit during storage at room temperature. These results suggest that suitable O3 treatment is a useful method for maintaining Qiushui pear fruit quality and extending their postharvest life; it might have potential application in pear fruit preservation.