عنوان مقاله [English]
Background and Objectives
Study of phytochemical changes of fruits has a great importance for plant physiologists and pomologists. Date is an important horticultural fruit in Iran which is mainly produced in southern regions. Barhee is considered as one of the most important date palm cultivars. The fruit of cv. Barhee can be harvested and consumed at different maturation stages including Khalal, Rutab and Tamar. In present study the biochemical alterations of date fruit cv. Barhee during development and ripening stages were studied.
Material and Methods
The experiment was carried out in a randomized complete block design with three replications. Sampling was done at Date Palm Research Institute Collection Orchard located in Ahwaz. To do that, fruits were harvested in five different developmental stages including late Kimri, Khalal, mainly Khalal, mainly Rutab, fully Rutab and Tamar. The fruits were transferred to Quality Analysis Lab of Department of Horticultural Science of Shahid Chamran University of Ahvaz. Selected uniform fruits were used for analysis of different phytochemical compounds. Chlorophyll, carotenoid, starch, soluble sugars, phenolic compounds, flavonoids and antioxidant capacity were analysed using spectrophotometric methods and the type and concentration of sugars, organic acids and phenolics were assessed using HPLC. Also vitamin C content was determined by titration againt DCIP dye.
The results showed that soluble sugars increased significantly during ripening stages, and glucose and fructose were the main detected sugars for Barhee cultivar. The amount of sucrose was negligible. The acidity of the fruit increased at initial growth stages and then decreased gratually till Rutab stage. At the end of ripening process and at Tamar stage, the amount of organic acid content increased to 2.45 mg/g FW. Among the detected organic acids, acetic acid was dominant in Tamar stage, while in the earlier stages malic acid was considered as the main organic acid. Other major compounds that have been investigated, including flavonoids, chlorophylls, carotenoids, starch and vitamin C decreased during development. Different compounds including p-cinamic, gintistic, gallic, chlorogenic, vanilic, caffeic, syringic and p-cumaric acids were detected by HPLC evaluation of phenolic acids. Among them, gallic acid was the dominant, and the trend was incremental during development of fruit.
The comparing the current results with published data for other date cultivars, says that there are big differences in biochemical compounds among different cultivars. In this cultivar, the increasing trend of accumulation of soluble sugars, organic acids, phenolic compounds and antioxidant capacity during ripening stages from late Kimri to Rutab and Tamar stage, makes the fruit an important source of high nutritional value.