Acta Pharmaceutica, Vol. 54 No. 1, 2004.
Short communication, Note
Quantitative analysis of the flavonoids in raw propolis from northern Croatia
IVAN KOSALEC
MARINA BAKMAZ
STJEPAN PEPELJNJAK
SANDA VLADIMIR-KNEZEVIC
Abstract
Spectrometric analyses of flavonoids in twenty propolis samples collected from ten different geographic localities in northern Croatia using two complementary methods, are reported. Flavones and flavonols were determined using aluminum chloride and expressed as quercetine equivalent while flavanones were determined using 2,4-dinitrophenylhydrazine and expressed as naringenin. Contents of flavones and flavonols were similar for most samples and ranged from 2 to 2.3%, except for one sample with a concentration of 1.3% and one sample in which it was not possible to detect flavones and flavonols. The content of flavanones in propolis samples is very variable. 55% of samples contain flavanons between 15 and 24% and 45% of samples between 4 and 14%. Total levels of flavonoids in raw propolis samples ranged between 5 and 26%; for the majority of samples (75%), the total level of flavonoids ranged between 15 and 25.9%. The high variability of flavanone concentration will affect biological activity of propolis preparations.
Keywords
propolis; flavonoids; flavones; flavonols; flavanones; Croatia
Hrčak ID:
16835
URI
Publication date:
1.3.2004.
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