Activity of Compounds from Temperate Propolis againstand.
Molecules. 2021 Jun 26 ;26(13). Epub 2021 Jun 26. PMID: 34206940
Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against threestrains and displayed ECvalues<20µg/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry, as 3-acetoxypinobanksin, tectochrysin, kaempferol, pinocembrin, 4'-methoxykaempferol, galangin, chrysin, apigenin, pinostrobin,cinnamic acid, coumaric acid, cinnamyl ester/coumaric acid benzyl ester (mixture), 4',7-dimethoxykaempferol, and naringenin 4',7-dimethyl ether. The isolated compounds were tested against drug-sensitive and drug-resistant strains ofand, with the highest activities≤ 15 µM. The most active compounds againstwere naringenin 4',7 dimethyl ether and 4'methoxy kaempferol with activity of 15-20µM against the threestrains. The most active compounds againstwere 4',7-dimethoxykaempferol and the coumaric acid ester mixture, with ECvalues of 12.9± 3.7 µM and 13.1 ± 1.0 µM. No loss of activity was found with the diamidine- and arsenical-resistant or phenanthridine-resistantstrains, or the miltefosine-resistantstrain; no clear structure activity relationship was observed for the isolated compounds. Temperate propolis yields multiple compounds with anti-kinetoplastid activity.