Simultaneous determination of 20 phenolic compounds in propolis by HPLC-UV and HPLC-MS/MS

Propolis is rich in flavonoids and phenolic acids, which has strong antioxidant capacity. Two methodologies for simultaneous determination of 20 phenolic compounds in propolis by HPLC-UV and HPLC-MS/MS were developed. The sample extraction and chromatographic separation conditions, and ultraviolet detection wavelength, as well as mass spectrometry parameters were selected and optimized. Under the optimized conditions, good linearities (R2≥0.998) were obtained for all analytes. The limits of quantification (LOQs) of the proposed methods by HPLC-UV and HPLC-MS/MS for all analytes were in the range of 0.02–0.1 mg/g and 0.05–0.2 mg/g, respectively, and the recoveries were in the range of 95.4 %− 109.5 % and 94.0 %− 106.8 % with the relative standard deviations (RSDs) in the range of 1.1 %− 7.5 % and 0.4 %− 11.1 %, respectively. The proposed methods were applied for the determination of 20 phenolic compounds in 13 propolis samples collected from China and Brazil. The detection results of the two methods are almost consistent with each other, indicating that both methods are applicable, and the inter-confirmation of the two methods can improve the accuracy of the determination of phenolic components in propolis.