Development and validation of a LC-method for determination of catechin and epicatechin in aqueous extractives from leaves of Maytenus ilicifolia

A reverse phase-LC method was developed and validated for separation and quantification of catechin and epicatechin in aqueous extractives from leaves of Maytenus ilicifolia. The analysis was performed using a C 18 column with acetic acid–acetonitrile gradient elution. The detection was carried out by UV at 280 nm and the peak identification was based on the retention times and by co-chromatography with reference substances. High coefficients of determination were achieved for both catechin and epicatechin peaks from the standard solutions (0.9996 and 0.9999), as well as from extractives (0.9981 and 0.9982, respectively). The method showed good repeatability (R.S.D.