Determination of Several Procyanidins in Litchi Pericarp by HPLC with Pass-through Extraction

Abstract:

A method was established in this study for determining the contents of catechin (C)，epicatechin (EC)，gallic acid (GA)，procyanidin B2 (PCB2)，procyanidin B4 (PCB4) and procyanidin A2 (PCA2) in litchi pericarp. The samples were extracted with 85% aqueous ethanolic solution and purified by Oasis PRiME HLB solid-phase extraction column, and analyzed by HPLC. The chromatographic column was thermo Syncronis C18 (250×4.6 mm, 5 μm), with methanol and 1 % glacial acetic acid as the mobile phase in gradient elution at a flow rate of 1.0 mL/min, column temperature at 35 ℃ and detection wavelength at 280 nm. The separation was carried out using consisting of. In the range of 0.5~100 mg/L, the concentrations of catechin, epicatechin, gallic acid, procyanidin B2, procyanidin B4 and procyanidin A2 had a good linear relationship with the peak areas with coefficients all higher than 0.9998. The average spiking recovery rates were 83.00%~102.00%, with relative standard deviations (RSD) between 0.48% and 0.83 %. The limits of detection (LOD, S/N=3) were 0.52, 0.55, 0.35, 0.45, 0.95 and 0.65 mg/kg, and the limits of quantification (LOQ, S/N=10) were 1.26, 1.64, 0.95, 1.35, 2.80 and 1.45 mg/kg for catechin, epicatechin, gallic acid, procyanidin B2, procyanidin B4 and procyanidin A2, respectively. This method is simple, rapid, accurate, reproducible, and can be used for the simultaneous quantitative determination of catechin, epicatechin, gallic acid, procyanidin B2, procyanidin B4 and procyanidin A2 in litchi pericarp.