Phytochemical Profiling of Aged Garlic Extract

The phytochemical profile of AGE was investigated by liquid chromatography coupled with diode array detection and electrospray/ion-trap tandem mass spectrometry (LC-DAD-ESI-MS/MS) analysis. Separation was carried out by a Luna Omega PS C18 column (150 × 2.1 mm, 5 μm; Phenomenex, Torrance, CA, USA) at RT and with a flow rate of 0.4 mL/min using 0.1% formic acid (Solvent A) and methanol (solvent B) as mobile phase, according to the elution program and mass spectrometer parameters reported in Smeriglio et al. [27 (link)]. Mass spectra were acquired using a fragmentation energy of 1.2 V (MS/MS). The peaks were identified by comparing retention times, UV–VIS and mass spectra of the analytes with those of commercially available HPLC-grade reference standards (purity ≥ 95%), as well as by comparison with those reported in literature, and quantified by using external calibration curves of oregonin (1–50 μg/mL) for diarylheptanoids and quercetin-3-O-glucoside for quercetin derivatives.