Abstract:In order to clarify the pharmacodynamic basis of water extract from Vicia faba flowers, the chemical constituents were analyzed and identified by ultra performance liquid chromatography electrospray ion source quadrupole time of flight mass spectrometry (UPLC-ESI-QTOF-MS), and the antioxidant activity was determined. The results showed that 178 components were identified from the water extract, and the relative contents of 107 components were more than 0.01%. The components with higher relative content included scutellarein 7-neohesperidoside, indoxyl glucuronide, spirolide E, rutin, propylene glycol alginate, kaempferol 3-α-d- galactoside, xanthurenic acid, and so on. The main components of flower water extract were flavonoids and alkaloids, with 16 and 19 kinds, and their relative contents were 36.53% and 34.33%, respectively. The IC50 of flower water extract for scavenging DPPH and ABTS+ free radical was 26.5 and 25.0 µg/mL, respectively. Therefore, flavonoids and alkaloids were the main substance basis of V. faba flower, and the water extract had strong antioxidant activity, indicating V. faba flowers had high application value.