{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T21:10:49Z","timestamp":1793481049948,"version":"4.5.0"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,6,24]],"date-time":"2022-06-24T00:00:00Z","timestamp":1656028800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007771","name":"Medical University of Silesia","doi-asserted-by":"publisher","award":["PCN-2-087\/N\/0\/I"],"award-info":[{"award-number":["PCN-2-087\/N\/0\/I"]}],"id":[{"id":"10.13039\/100007771","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>The spread of antibiotic resistance among bacteria has become one of the major health problems worldwide. Methicillin-resistant staphylococcal strains are especially dangerous because they are often resistant to other antibiotics. The increasing insensitivity to macrolides, lincosamides and streptogramin B antibiotics of methicillin-resistant staphylococcal isolates has limited the use of these drugs in therapy. The combination of natural compounds and antibiotics can be considered as an alternative tool to fight multi-drug-resistant pathogen infections. The aim of the presented study was to examine the antibacterial activity of protocatechuic acid ethyl ester\u2013erythromycin combination towards Staphylococcus aureus and Staphylococcus epidermidis strains with various resistance profiles to methicillin and macrolides, lincosamides and streptogramin B (MLSB) antibiotics. The in-vitro antibacterial potential of the above combination was investigated by minimum inhibitory concentration assays and checkerboard testing. The observed effects were strain dependent, with 8 of 12 tested staphylococcal strains showing an indifferent effect on the natural compound and erythromycin; for 2 strains, the tested combination had an additive effect, while for another 2, the effect was synergistic. Interestingly, the multi-drug-resistant strains were more sensitive to the cooperative action of the protocatechuic acid ethyl ester and the antibiotic.<\/jats:p>","DOI":"10.3390\/antibiotics11070848","type":"journal-article","created":{"date-parts":[[2022,6,25]],"date-time":"2022-06-25T10:39:13Z","timestamp":1656153553000},"page":"848","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["The Array of Antibacterial Action of Protocatechuic Acid Ethyl Ester and Erythromycin on Staphylococcal Strains"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8607-8866","authenticated-orcid":false,"given":"Maria","family":"Miklasi\u0144ska-Majdanik","sequence":"first","affiliation":[{"name":"Department of Microbiology and Virology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiello\u0144ska 4, 41-200 Sosnowiec, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4013-6688","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"K\u0119pa","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Virology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiello\u0144ska 4, 41-200 Sosnowiec, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monika","family":"Kulczak","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Virology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiello\u0144ska 4, 41-200 Sosnowiec, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maciej","family":"Ochwat","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Virology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiello\u0144ska 4, 41-200 Sosnowiec, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6525-9767","authenticated-orcid":false,"given":"Tomasz J.","family":"W\u0105sik","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Virology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiello\u0144ska 4, 41-200 Sosnowiec, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3551","DOI":"10.2147\/IJN.S246484","article-title":"Synergistic Ros-Associated Antimicrobial Activity of Silver Nanoparticles and Gentamicin against Staphylococcus epidermidis","volume":"15","author":"Mazur","year":"2020","journal-title":"Int. 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