Susceptibility of Staphylococcus aureus clinical isolates to propolis extract alone or in combination with antimicrobial drugs.
The objective of this study was to assess in vitro the antimicrobial activity of ethanolic extract of Polish propolis (EEPP) against methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates. The combined effect of EEPP and 10 selected antistaphylococcal drugs on S. aureus clinical cultures was also investigated. EEPP composition was analyzed by a High Performance Liquid Chromatography (HPLC) method. The flavonoid compounds identified in Polish Propolis included flavones, flavonones, flavonolols, flavonols and phenolic acids. EEPP displayed varying effectiveness against twelve S. aureus strains, with minimal inhibitory concentration (MIC) within the range from 0.39 to 0.78 mg/mL, determined by broth microdilution method. The average MIC was 0.54 ± 0.22 mg/mL, while calculated MIC₅₀ and MIC₉₀ were 0.39 mg/mL and 0.78 mg/mL, respectively. The minimum bactericidal concentration (MBC) of the EEPP ranged from 0.78 to 3.13 mg/mL. The in vitro combined effect of EEPP and 10 antibacterial drugs was investigated using disk diffusion method-based assay. Addition of EEPP to cefoxitin (FOX), clindamycin (DA), tetracycline (TE), tobramycin (TOB), linezolid (LIN), trimethoprim+sulfamethoxazole (SXT), penicillin (P), erythromycin (E) regimen, yielded stronger, cumulative antimicrobial effect, against all tested S. aureus strains than EEPP and chemotherapeutics alone. In the case of ciprofloxacin (CIP) and chloramphenicol (C) no synergism with EEPP was observed.
Department and Institute of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Katowice, Poland.
Robert D
RD
Wojtyczka
Arkadiusz
A
Dziedzic
Danuta
D
Idzik
Małgorzata
M
Kępa
Robert
R
Kubina
Agata
A
Kabała-Dzik
Joanna
J
Smoleń-Dzirba
Jerzy
J
Stojko
Mieczysław
M
Sajewicz
Tomasz J
TJ
Wąsik
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D004357:Drug Synergism; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics; D011429:Propolis / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D011429:Propolis