HPTLC determination of xanthohumol in hops (Humulus lupulus L.) and hop products

A sensitive thin-layer chromatographic method has been established for quantification of xanthohumol in hops (Humulus lupulus L.) and hop products. Chromatographic separation was performed on silica gel 60 HPTLC plates with toluene-dioxane-acetic acid, 77 + 20 + 3 (v/v), as mobile phase. The plates were scanned densito-metrically at lambda = 368 nm. The method was validated for precision, repeatability, and accuracy. It was found to be precise - intra-day and inter-day RSD were 1.7% and 2.3%, respectively. Instrumental precision and repeatability for the method were found to be 0.38 and 1.5 (%CV), respectively. The accuracy was checked by measuring the recovery at three levels; average recovery was 103.9%. The method was used for the estimation of xanthohumol in hop extracts and xanthohumol-enriched beer and was confirmed to be suitable for this purpose.