Antibacterial activity of Brazilian propolis and fractions against oral anaerobic bacteria

Propolis collected from a cerrado area in Minas Gerais State, Brazil, was subjected to chromatography on silica gel column and to partition between immiscible solvents. Propolis aqueous-ethanolic extract and fractions obtained were tested for inhibitory activity against periodontitis-causing bacteria. All of the assayed bacterium species were susceptible to propolis extract. The two fractionation methodologies yielded fractions which were active against bacteria, with minimum inhibitory concentrations (MIC) ranging from 64 to 1024 mug/ml. TLC and HPLC analyses of the extract and of active fractions showed the presence of phenolic compounds of varied polarity. None of the assayed fractions was more active than the extract, suggesting that the antibacterial activity is probably due to the synergistic effect of several compounds. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.