Detection of flavonoids from Spinacia oleracea leaves using HPLC-ESI-QTOF-MS/MS and UPLC-QqQ_LIT-MS/MS techniques

Spinacia oleracea L. (Spinach) is a leafy vegetable which is considered to have a high nutritional value. Flavonoids in spinach were reported to act as antimutagenic property. Rapid detection of these flavonoids in Spinach was achieved by using HPLC-ESI-QTOF-MS/MS. Thirty six compounds were tentatively identified based on their retention times, accurate mass and MS/MS spectra. The fragmentation patterns of known compounds were applied to elucidate the structure of their corresponding derivatives having the same basic skeleton. Out of thirty six peaks, three peaks were assigned as patuletin and six peaks were assigned as spinacetin derivatives. Twelve compounds were first time identified following the fragmentation pattern of known compounds. Five of the identified compounds i.e., spinacetin, 5,3',4'-trihydroxy-3-methoxy-6,7-methylenedioxyflavone, protocatechuic acid, ferulic acid and coumaric acid were simultaneously quantified in spinach leaves by a validated UPLC-ESI-MS/MS method under MRM mode.