OBJECTIVETo develop an LC-MS method for identification of flavonoids in Chinese hawthorn fruits and an HPLC method for quantification of 5 flavonoids.

METHODAccurate molecular weights of the target flavonoids were acquired by time-of-flight mass spectrometer (TOF-MS) in both positive and negative ion modes. The flavoniods were then further confirmed by standards. An RP-HPLC method was established to quantitatively analysis five major flavonoids (chlorogenic acid, procyanidin B2, epicatechin, hyperoside and isoquercitrin) in hawthorn fruits from ten different regions.

RESULTSThe molecular formulae of 8 components were determined by TOF-MS. In the quantitative method validation, the method is linear over the studied range of 1.8-178.5, 2.2-284.8, 2.7-270. 6,1.5-150.0, 1.5-150.0 mg x L(-1) for chlorogenic acid, procyanidin B2, epicatechin, hyperoside and isoquercitrin, respectively. The correlation coefficient for each analyze was greater than 0.999. The inter-day precision of the analysis was lower than 4%, The RSDs of precision and stability were lower than 5%. The recovery rate was from 98.5% to 102.5%, and RSDs were less than 3.5%.

CONCLUSIONThe method is simple, specific and reliable, and is suitable for quality control of Chinese hawthorn.