{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T19:37:20Z","timestamp":1770493040041,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,7,10]],"date-time":"2023-07-10T00:00:00Z","timestamp":1688947200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Portuguese Foundation for Science and Technology\/MCTES","doi-asserted-by":"publisher","award":["UIDB\/00709\/2020"],"award-info":[{"award-number":["UIDB\/00709\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Portuguese Foundation for Science and Technology\/MCTES","doi-asserted-by":"publisher","award":["UIDP\/00709\/2020"],"award-info":[{"award-number":["UIDP\/00709\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Staphylococcus aureus can exhibit resistance to various antibiotics. Among its resistance mechanisms, the active efflux of antibiotics can be seen as relevant. This study aimed to evaluate the ability of resveratrol to modulate norfloxacin resistance in S. aureus. The antimicrobial activity of resveratrol was assessed using the broth microdilution method to determine the minimum inhibitory concentration (MIC). Then, the modulatory effect of resveratrol was evaluated using the MIC determination for the antibiotic or ethidium bromide in the presence and absence of resveratrol at a sub-MIC level. The MIC of norfloxacin against S. aureus SA1199B (NorA-overexpressing strain) decreased 16-fold when in the presence of resveratrol, with a similar behavior being observed for ethidium bromide. An evaluation of the ethidium bromide accumulation was also performed, showing that in the presence of resveratrol, the SA1199B strain had augmented fluorescence due to the accumulation of ethidium bromide. Altogether, the results suggested that resveratrol may act by inhibiting NorA. These in vitro data were supported by docking results, with interactions between resveratrol and the NorA efflux pump predicted to be favorable. Our findings demonstrated that resveratrol may modulate norfloxacin resistance through the inhibition of NorA, increasing the effectiveness of this antibiotic against S. aureus.<\/jats:p>","DOI":"10.3390\/antibiotics12071168","type":"journal-article","created":{"date-parts":[[2023,7,10]],"date-time":"2023-07-10T00:35:21Z","timestamp":1688949321000},"page":"1168","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Resveratrol as an Inhibitor of the NorA Efflux Pump and Resistance Modulator in Staphylococcus aureus"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4884-6622","authenticated-orcid":false,"given":"Madalena","family":"Santos","sequence":"first","affiliation":[{"name":"CICS-UBI\u2014Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9904-0699","authenticated-orcid":false,"given":"Raquel","family":"Santos","sequence":"additional","affiliation":[{"name":"CICS-UBI\u2014Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilh\u00e3, Portugal"}]},{"given":"Pedro","family":"Soeiro","sequence":"additional","affiliation":[{"name":"CICS-UBI\u2014Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4297-5108","authenticated-orcid":false,"given":"Samuel","family":"Silvestre","sequence":"additional","affiliation":[{"name":"CICS-UBI\u2014Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8308-2862","authenticated-orcid":false,"given":"Susana","family":"Ferreira","sequence":"additional","affiliation":[{"name":"CICS-UBI\u2014Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5926","DOI":"10.1099\/ijsem.0.004498","article-title":"Phylogenomic analyses of the Staphylococcaceae family suggest the reclassification of five species within the genus Staphylococcus as heterotypic synonyms, the promotion of five subspecies to novel species, the taxonomic reassignment of five Staphylococcus species to Mammaliicoccus gen. nov., and the formal assignment of Nosocomiicoccus to the family Staphylococcaceae","volume":"70","author":"Madhaiyan","year":"2020","journal-title":"Int. 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