Oxyprenylated ferulic acid derivatives in Italian citrus liqueurs

4'-Geranyloxyferulic and boropinic acid have been recently found as phytochemicals exerting promising pharmacological effects as cancer chemopreventive, anti-inflammatory, neuroprotective, and anti-Helicobacter pylori agents. An RP HPLC-UV/Vis method for the qualitative and quantitative analysis of these oxyprenylated derivatives in handmade citrus-based typical Italian liqueurs like limoncello, arancello, and mandarinetto was successfully performed. Concentration values showed a great variation between the different liquors, limoncello, from Abruzzo region, being the richest one both in 4'-geranyloxyferulic acid (1.68 ± 0.03 µg/ml of liquor) and boropinic acid (0.16 ± 0.01 µg/ml). Only in two cases boropinic acid was not detected.