Brazilian red propolis: unreported substances, antioxidant and antimicrobial activities.
Righi AA, Alves TR, Negri G, Marques LM, Breyer H, Salatino A.
Institute of Biosciences, Botany Department, University of São Paulo, 05508-090, São Paulo, SP, Brazil. email@example.com.
Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Antimicrobial and antioxidant activities were also obtained.
The propolis sample contained low content of narigenin-8-C-hexoside, this being the first report of a C-glycoside in propolis. The main constituent found was characterized as 3,4,2′,3′-tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)-vestitol, (3S)-7-O-methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans-anethol, methyl eugenol, elimicin, methoxyeugenol and cis-asarone, and the triterpenic alcohols lupeol and α- and β- amyrins. The methanol extract exhibited high antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl and β-carotene/linoleic acid assay methods, and antimicrobial activity toward Gram-positive and Gram-negative bacteria.
Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2′,3′-tetrahydroxychalcone and a flavone C-glycoside in a propolis sample. Copyright © 2011 Society of Chemical Industry.
Copyright © 2011 Society of Chemical Industry.
* THESE STATEMENTS HAVE NOT BEEN EVALUATED BY THE FOOD AND DRUG ADMINISTRATION. THIS IS NOT INTENDED TO DIAGNOSE, TREAT CURE OR PREVENT ANY DISEASE.