Determination of flavonoids in propolis-rich functional foods by reversed phase high performance liquid chromatography with diode array detection

► Flavonoids in propolis-rich functional foods were determined by a HPLC-DAD method. ► Ten flavonoids were separated by a rapid and simple gradient elution within 40 min. ► A simple, rapid and efficient ultrasonic-assisted extraction procedure was developed. ► Use of methanol as the extracting solvent could avoid emulsification and interference. ► The HPLC-DAD method was less costly, more common and suitable for routine analysis.