title: Antibacterial Activity of Protocatechuic Acid Ethyl Ester on Staphylococcus aureus Clinical Strains Alone and in Combination with Antistaphylococcal Drugs.
abstract: The aim of the presented study was to examine in vitro the antibacterial activity of protocatechuic acid ethyl ester (ethyl 3,4-dihydroxybenzoate, EDHB) against Staphylococcus aureus clinical isolates alone and in the combination with four selected antibiotics. The EDHB antimicrobial activity was tested against twenty S. aureus strains isolated from the clinical samples, and three reference strains. The phenotypes and genotypes of resistance to methicillin for the tested strains were defined as well as the phenotypic resistance to macrolides, lincosamides and streptogramin B (MLSB). EDHB displayed diverse activity against examined S. aureus strains with the minimal inhibitory concentration (MIC) within the range from 64 to 1024 µg/mL. Addition of ¼ MIC of EDHB into the Mueller-Hinton Agar (MHA) resulted in augmented antibacterial effect in the presence of clindamycin. In the case of cefoxitin no synergistic effect with EDHB was noted. For erythromycin and vancomycin the decrease of mean MICs in the presence of EDHB was observed but did not reach statistical significance. The results of the present study showed that in vitro EDHB possesses antibacterial activity against S. aureus clinical strains and triggers a synergistic antimicrobial effect with clindamycin and to the lesser extent with erythromycin and vancomycin.
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. maria.miklasinska@o2.pl.
authors.forename: Maria
authors.initials: M
authors.lastname: Miklasińska
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. mkepa@sum.edu.pl.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Kępa
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. rwojtyczka@sum.edu.pl.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Wojtyczka
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. didzik@sum.edu.pl.
authors.forename: Danuta
authors.initials: D
authors.lastname: Idzik
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. anna.zdebik@gmail.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Zdebik
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. kamila_orlewska@o2.pl.
authors.forename: Kamila
authors.initials: K
authors.lastname: Orlewska
authors.affiliation: Department of Microbiology and Virology, School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, ul. Jagiellońska 4, 41-200 Sosnowiec, Poland. twasik@sum.edu.pl.
authors.forename: Tomasz J
authors.initials: TJ
authors.lastname: Wąsik
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000187:drug effects*; D006801:Humans; D062385:Hydroxybenzoates / Q000737:chemistry / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000254:growth & development* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D062385:Hydroxybenzoates
keywords: Staphylococcus aureus; antibacterial activity; protocatechuic acid ethyl ester; synergistic effect