Effect of pre‐harvest salicylic acid spray treatment on post‐harvest antioxidant in the pulp and peel of ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck)

Abstract

AbstractBACKGROUND: Exogenous salicylic acid (SA) pretreatment could change the antioxidant system and maintain the nutritional value of fruits and vegetables, which have a higher ability to withstand oxidation injuries. However, the relationship between a pre‐harvest SA spray and post‐harvest antioxidant compounds in fruit remains unknown.RESULTS: The post‐harvest behaviour of antioxidant compounds in ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck) fruit was investigated in relation to the pre‐harvest SA applications. Pre‐harvest SA treatment significantly increased the content of carotenoids (lycopene and α‐carotene), ascorbic acid, glutathione, total phenolics, and total flavonoids in the pulp and peel during storage. Furthermore, the values of these antioxidant compounds were high in the fruit treated with high SA concentrations (1.0 and 2.0 mmol L−1). High antioxidant activity was also observed in the SA pre‐harvest treated fruit when compared with the control. The positive relationships were found between the antioxidant activity and the content of these active compounds.CONCLUSION: These results indicated that SA could maintain fruit antioxidant activity and nutrition which was shown by the increase in content of antioxidant compounds and suggested that pre‐harvest treatment with SA promised a novel technology, which was a substitute for the perplexing programme control of post‐harvest nutrition in fruit. Copyright © 2007 Society of Chemical Industry