SUMMARY
The chemical composition of propolis was investigated. This type of investigations was extremely valuable with respect to propolis standardization and practical applications in therapy. In this study are two methods presented for two flavonoids group determination: flavone/flavonols (FF)–AlCl3, and flavanones/dihydroflavonols (FD)–2,4-dinitrophenylhidrazine.Transylvanian propolis taken into analysis had an amount of 6.61% flavone/flavonols, 3.02% flavanones/dihydroflavonols and about 10% total flavonoids typical for propolis derived from Populus sp. Total phenolic content was measured by the Folin-Ciocalteu procedure using a mixture of Pinocembrin and Galangin as internal standards. The analyzed samples of propolis presented an average of 35.60% of phenolic compounds. The extraction of active principles from propolis was performed and the average of the extraction yield was found to be 60% ± 7.7%.