Screening of phenolic content and antioxidant capacity of Okitsu mandarin (Citrus unshui Marc.) fruits extracted with various solvents
The main purpose of this work is to compare the effect of using various solvents to obtain phenolic extract from ‘Satsuma Okitsu’ mandarin (Citrus unshui Marc.) juice and characterize their phenolic profiles and determine their antioxidant capacity. Three different solvent used to extract phenolic content of mandarin juice as water, methanol and ethanol. A total of 17 phenolic compounds identified and quantified in all samples by LC-DAD-ESI-MS/MS. According to results, among all phenolics, narirutin (naringenin-7-O-rutinoside) was the most abundant compound with the concentrations of 164.3, 201.2 and 203.7 mg L-1 for the aqueous, methanolic and ethanolic extracts respectively. In the aqueous extract, narirutin followed by feruloyl-galactaric acid and luteolin-6,8-di-C-glucoside with 66.4 and 61.5 mg L-1. However, hesperidin (hesperetin-7-O-rutinoside) was the second most abundant compound in methanolic and ethanolic extracts with the concentrations of 83.9 and 125.0 mg L-1. In addition, the total amount of phenolic compounds ranged from 532,1 691,3 755,6 mg L-1 in the mandarin juice for the aqueous, methanolic and ethanolic extracts respectively. Beyond the phenolic profiles, antioxidant capacity of three extracts were investigated by means of DPPH and ABTS assays. According to revealed results, in parallel with the phenolic compounds concentrations, the ethanolic extracts possessed the highest antioxidant activity followed by methanolic extracts for both radicals.