COMPARISON HPLC AND FLUORESCENCE SPECTROMETRY METHODS FOR DETERMINATION OF COUMARIN DERIVATIVES IN PROPOLIS

Abstract

This paper illustrates the composition of propolis samples obtained from two regions in the Slovak Republic and focuses on the determination of coumarins. The HPLC method with on-line spectrophotometric and fluorescent detection was used for the separation and the determination of coumarins from the subgroup of simple coumarins (esculin, daphnetin, fraxetin, umbelliferone, 4-methylumbelliferone, 4-hydroxycoumarin, scoparone, coumarin, herniarin) and cinnamyl alcohol. The results confirmed that the quantity of umbelliferone, 4-methylumbelliferone, and scoparone in the propolis depends on the area of collection. The HPLC results were compared with those obtained by the spectrofluorimetric method developed for the determination of total coumarins (calculated as scoparone). For the quantification of total coumarins in propolis extracts we found 15% higher values of coumarin content by fluorescence spectrometry than by HPLC, which can be ascribed to the higher matrix effects on fluorescence spectra.

Keywords:

• coumarins
• HPLC
• propolis
• spectrofluorimetry

ACKNOWLEDGMENT

This study was financially supported by the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and of Slovak Academy of Sciences (grant no. 1/0164/11).

Notes

^{a, b} Concentration level of 10 µg/mL (UV, 280 nm).

^c 323 nm.

^d 280 nm.

^a µg/g.

^b ng/g.

^a Fluorescence detection.

^b Concentration level of 1 µg/mL.

^c Mean value for concentration level of 10 ng/mL and 20 ng/mL.