A systematic UHPLC Q-ToF MS approach for the characterization of bioactive compounds from freeze-dried red goji berries (L. barbarum L.) grown in Serbia: Phenolic compounds and phenylamides

The aim of this study was to identify and characterise different classes of bioactive compounds from freeze-dried red goji berries (RGB) grown in Serbia, using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC Q-ToF MS). In addition, this study aims to demonstrate the importance of applying the advanced UHPLC Q-ToF MS technique in the identification of various biocompounds. The analysis showed the presence of 28 phenolic compounds, 3 organic acids, and 26 phenylamides. The 2-O-β-d-glucopyranosyl-l-ascorbic acid (AA-2βG) was identified by UHPLC Q-ToF MS and quantified by standardised UHPLC-DAD method. Most of the compounds detected were derivatives of caffeic acid and ferulic acid, followed by quercetin derivatives. Among the phenylamides, several glucosylated caffeoyl and/or dihydrocaffeoyl derivatives of spermidine and spermine were characterized, confirming their recent characterization. Some glycosylated/non-glycosylated putrescine derivatives and caffeoyl-dihydrocaffeoyl-feruloyl spermidines were identified in goji berriesfor the first time. Their tentative structures and fragmentations were proposed.