Effect of sodium nitroprusside on antioxidative enzymes and the phenylpropanoid pathway in blueberry fruit.

The purpose of this study is to investigate the effects of sodium nitroprusside (SNP) treatment after harvest on the activity of antioxidative enzymes and the phenylpropanoid pathway of blueberries. Blueberry fruits were dipped in 1.0 mmol/L SNP solution for 10 min and stored at 4 °C. Fruits treated with distilled water were used as the control. The results indicated that SNP significantly inhibited the increase of weight loss and enhanced the ascorbic acid content of blueberry fruit. Moreover, SNP increased the activity of phenylalanine ammonia-lyase, 4-coumarate-CoA ligase, polyphenol oxidase, superoxide dismutase, glutathione reductase, ascorbate peroxidase, peroxidase, and hydrogen peroxide in blueberry fruit. The accumulation of lignin and anthocyanin in the fruit was also stimulated by the SNP treatment. These results demonstrate that SNP treatment could maintain the antioxidant ability of blueberries by regulating the phenylpropanoid pathway and antioxidant enzymes.