Morphological, physico-chemical characteristics and effects of extraction solvents on UHPLC-DAD-ESI-MSn profiling of phenolic contents and antioxidant activities of five date cultivars (Phoenix dactylifera L.) growing in Algeria

The aim of this study was to evaluate the morphological, physico-chemical characteristics and in vitro antioxidant activity (DPPH, FRAP, total antioxidant activity, Fe2+-chelating activity and CUPRAC) of five date cultivars (Phoenix dactylifera L.) growing in Algeria. The fruits are characterized as being economically important via their PH values, weight and quality. The highest level of total phenolic and condensed tannins contents was found in 80% methanol extracts. This level ranged from 20.38-69.85 mg GAE/100 g DW and between 3.58 and 60.05 mg CE/100 g DW. The highest total flavonoid contents were found in acetonic extracts. The fruits exerted different antioxidant activities and they were influenced by the extraction solvent. Although they have low phenolic contents, 70% acetone extracts gave the highest antioxidant activities. Using UHPLC-DAD-ESI-MSn analysis, 19 compounds were identified, most detected compounds were found in 70% acetonic extracts. Thus, 70% acetone was found to be the best solvent to run such investigation. Due to date-pathogen, infected Tinnaser date synthesized more or new polyphenols such as O-p-coumaroylshikimic acid and apigenin pentosyl hexoside.