Objective: To develop a simple and sensitive high performance liquid chromatographic method for simultaneous determination of catechin hydrate, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, dihydromyricetin, glycyrrhizic acid and glycyrrhetinic acid in healthy food for anti-hangover and hepatoprotection, and compare with the capillary electrophoresis method established by our laboratory.
Methods: The samples were ultrasonically extracted by using methanol-water( 4∶ 1, V/V) for 30 minutes and then centrifuged at 10 000 r/min for 10 minutes. The supernatant was filtered and injected into the HPLC system and then separated on a C_(18) column( 5 μm × 250 mm × 4. 6 mm) at 30℃ with gradient elution at a flow rate of 0. 8mL/min. Catechins and dihydromyricetin were detected at the wavelength of 210 nm, glycyrrhizic acid and glycyrrhetinic acid were detected at 250 nm.
Results: Under the optimal analytical conditions, the peak area of each analyte and its concentration had agood correlation within the linear range( r ≥ 0. 9996). The limits of detection and quantification of the method were 0. 07-1. 25 μg/g( S/N = 3) and 0. 22-4. 18 μg/g( S/N = 10), respectively. The intra-and inter-day relative standard deviations( RSDs)of the mixed standard solution were 0. 26%-1. 95% and 1. 17%-3. 89%, respectively. The spiked recoveries of the analytes were 86. 15%-98. 61%.
Conclusion: The established method is sensitive and reliable, and could be used for quality control of the healthy food for anti-hangover and hepatoprotection.
Keywords: catechins; dihydromyricetin; glycyrrhetinic acid; glycyrrhizic acid; high performance liquid chromatography.