| چکیده انگلیسی مقاله |
Background and Objective: Thomson navel orange has a high nutritional value due to the high concentration of vitamin C, fiber, folate, minerals, and phytochemical compounds such as flavonoids, amino acids, triterpenes, phenolic acids and carotenoids. The postharvest respiration of orange fruit may produce changes in its bioactive compounds. The objective of this study was to investigate changes in the bioactive compounds, including ascorbic acid, flavonoids, and total carotenoid concentrations, as well as antioxidant activity and respiration rate of Thomson navel oranges, during storage. Materials and Methods: Thomson oranges (citrus sinensis) var. navel were purchased from Iran Citrus Research Center (Ramsar) and transported to the laboratory immediately after harvest and kept in cold store at 4-5 °C and 85-90 % relative humidity for 65 days. Changes in the concentrations of vitamin C, flavonoid compounds and total carotenoids, as well as in the antioxidant capacity and respiration rate of the oranges, were measured at 7-day intervals. Results: Analysis of the data obtained showed that after 56 days of storage the concentrations of total flavonoides and total carotenoids, as well as the antioxidant activity and respiration rate of the oranges, increased by 36 %, 39 %, 19.6% and 94%, respectively, while the concentration of ascorbic acid decreased by 60.5% (p≤0.05). Effects of storage on the bioactive compounds concentrations, antioxidant activity, and respiration rate were significant )0.05). Changes in the concentrations of compounds with an antioxidant activity and the respiration rate affected the antioxidant activity of oranges during storage. Conclusion: Based on our results, and considering the nutritional value and functional compounds of orange fruit, using suitable technology to better protect the bioactive compounds and antioxidant activity of this valuable fruit is recommended. Keywords: Thomson orange, Bioactive compounds, Respiration rate, Antioxidant activity, Storage |