{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:22:45Z","timestamp":1792790565930,"version":"4.5.0"},"reference-count":46,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,12,16]],"date-time":"2024-12-16T00:00:00Z","timestamp":1734307200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      The persistence of\n                      <jats:italic>Acinetobacter baumannii<\/jats:italic>\n                      in the contaminated environment is sustained by tolerance to biocides and ability to growth as biofilm. The aim of the study was to analyze the susceptibility of\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      biofilms to chlorhexidine (CHX) and benzalkonium (BZK) biocides and the ability of natural monomeric stilbenoid resveratrol (RV) to modulate the phenomenon.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Biofilm formation and preformed biofilm were tested by Crystal violet and tetrazolium salt reduction assay, respectively. Analysis of efflux pump (EP) expression during biofilm growth was performed by Real-time RT-PCR assays.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      CHX and BZK at \u00bc and \u00bd MICs alone or in combination inhibited biofilm growth of\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ATCC 19606, 4190, and 3909 strains. RV at 32\u202fmg\/L and CHX and BZK at \u00bc or \u00bd MICs showed a synergistic effect and completely inhibited biofilm formation in all\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      strains. Similarly, RV at 32\u202fmg\/L and CHX and BZK at \u00bd MIC significantly inhibited air-liquid biofilm formation of\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ATCC 19606, 4190 and 3909 strains. The inactivation of AdeB and AdeJ RND EPs in\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ATCC19606 increased the susceptibility to CHX and BZK alone or in the presence of 32\u202fmg\/L RV. Concordantly, carbonyl cyanide m-chlorophenylhydrazine (CCCP) increased the susceptibility to CHX, BZK and RV and dose-dependently inhibited biofilm formation in\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ATCC 19606, 4190 and 3909 strains. RV at 32\u202fmg\/L inhibited basal and CHX-induced EP genes expression, while increased EP gene expression in the presence of BZK during\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ATCC19606 biofilm growth. In addition, CHX and BZK alone or in combination dose-dependently reduced preformed biofilm of all\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      strains. The combination of RV with CHX and BZK additively decreased minimal biofilm eradicating concentrations in\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      strains.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      These results demonstrate that: (i) CHX and BZK alone or in the presence of RV inhibit biofilm growth and preformed biofilm in\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      ; (ii) tolerance to CHX and BZK during biofilm growth is dependent on the activation of AdeB and AdeJ EPs; and (iii) the inhibitory effect of RV on biofilm growth is mediated by the inhibition of EP genes expression in\n                      <jats:italic>A. baumannii<\/jats:italic>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmicb.2024.1494772","type":"journal-article","created":{"date-parts":[[2024,12,16]],"date-time":"2024-12-16T10:50:47Z","timestamp":1734346247000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":16,"title":["Inhibition of biofilm formation and preformed biofilm in Acinetobacter baumannii by resveratrol, chlorhexidine and benzalkonium: modulation of efflux pump activity"],"prefix":"10.3389","volume":"15","author":[{"given":"Antonella","family":"Migliaccio","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Stabile","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Triassi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuelle","family":"D\u00e9","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eliana","family":"De Gregorio","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raffaele","family":"Zarrilli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2024,12,16]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"87","DOI":"10.1016\/j.jhin.2012.03.003","article-title":"Klebsiella pneumoniae susceptibility to biocides and its association with cepA, qacDE and qacE efflux pump genes and antibiotic resistance","volume":"81","author":"Abuzaid","year":"2012","journal-title":"J. Hosp. Infect."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"50","DOI":"10.1016\/j.micpath.2016.06.016","article-title":"Biofilm inhibitory effect of chlorhexidine conjugated gold nanoparticles against Klebsiella pneumoniae","volume":"98","author":"Ahmed","year":"2016","journal-title":"Microb. Pathog."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"3531","DOI":"10.1038\/s41467-023-39316-5","article-title":"A polyamine acetyltransferase regulates the motility and biofilm formation of Acinetobacter baumannii","volume":"14","author":"Armalyt\u0117","year":"2023","journal-title":"Nat. Commun."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"001340","DOI":"10.1099\/mic.0.001340","article-title":"Biofilms as protective cocoons against biocides: from bacterial adaptation to One Health issues","volume":"169","author":"Charron","year":"2023","journal-title":"Microbiology"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"769","DOI":"10.1093\/cid\/ciy988","article-title":"Treatment outcomes of colistin- and carbapenem-resistant Acinetobacter baumannii infections: an exploratory subgroup analysis of a randomized clinical trial","volume":"69","author":"Dickstein","year":"2019","journal-title":"Clin. Infect. Dis."},{"key":"ref6","doi-asserted-by":"publisher","first-page":"221","DOI":"10.3390\/dj12070221","article-title":"Insights into the cytotoxicity and irritant potential of chlorhexidine Digluconate: an In vitro and In Ovo safety screening","volume":"12","author":"Dinu","year":"2024","journal-title":"Dent. J."},{"key":"ref7","doi-asserted-by":"publisher","first-page":"197","DOI":"10.1111\/j.1469-0691.2010.03254.x","article-title":"Molecular epidemiological investigation of multidrug-resistant Acinetobacter baumannii strains in four Mediterranean countries with a multilocus sequence typing scheme","volume":"17","author":"Di Popolo","year":"2011","journal-title":"Clin. Microbiol. Infect."},{"key":"ref8","doi-asserted-by":"publisher","first-page":"e0197742","DOI":"10.1371\/journal.pone.0197742","article-title":"Dissection of the antimicrobial and hemolytic activity of Cap18: generation of Cap18 derivatives with enhanced specificity","volume":"13","author":"Ebbensgaard","year":"2018","journal-title":"PLoS One"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"21519","DOI":"10.1039\/c9ra03673c","article-title":"Expeditious synthesis and preliminary antimicrobial activity of deflazacort and its precursors","volume":"9","author":"Esposito","year":"2019","journal-title":"RSC Adv."},{"key":"ref10","doi-asserted-by":"publisher","first-page":"3222","DOI":"10.1093\/jac\/dkv262","article-title":"Reduced susceptibility to biocides in Acinetobacter baumannii: association with resistance to antimicrobials, epidemiological behaviour, biological cost and effect on the expression of genes encoding porins and efflux","volume":"70","author":"Fern\u00e1ndez-Cuenca","year":"2015","journal-title":"J. Antimicrob. Chemother."},{"key":"ref11","doi-asserted-by":"publisher","first-page":"1192","DOI":"10.1093\/jac\/dkz024","article-title":"The chloramphenicol\/H+ antiporter CraA of Acinetobacter baumannii AYE reveals a broad substrate specificity","volume":"74","author":"Foong","year":"2019","journal-title":"J. Antimicrob. Chemother."},{"key":"ref7001","doi-asserted-by":"publisher","first-page":"930","DOI":"10.3389\/fmicb.2019.00930","article-title":"Comparative analysis of the two Acinetobacter baumannii multilocus sequence typing (MLST) schemes","volume":"10","author":"Gaiarsa","year":"2019","journal-title":"Front. Biol."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"456","DOI":"10.1089\/mdr.2023.0074","article-title":"Biocides in the hospital environment: application and tolerance development","volume":"29","author":"Geraldes","year":"2023","journal-title":"Microb. Drug Resist."},{"key":"ref13","doi-asserted-by":"publisher","first-page":"282","DOI":"10.1186\/1471-2334-13-282","article-title":"Virulence-related traits of epidemic Acinetobacter baumannii strains belonging to the international clonal lineages I-III and to the emerging genotypes ST25 and ST78","volume":"13","author":"Giannouli","year":"2013","journal-title":"BMC Infect. Dis."},{"key":"ref14","doi-asserted-by":"publisher","first-page":"e0027621","DOI":"10.1128\/JCM.00276-21","article-title":"Update from the European Committee on antimicrobial susceptibility testing (EUCAST)","volume":"60","author":"Giske","year":"2020","journal-title":"J. Clin. Microbiol."},{"key":"ref15","doi-asserted-by":"publisher","first-page":"427","DOI":"10.1093\/jac\/11.5.427","article-title":"The fractional inhibitory concentration (FIC) index as a measure of synergy","volume":"11","author":"Hall","year":"1983","journal-title":"J. Antimicrob. Chemother."},{"key":"ref16","doi-asserted-by":"publisher","first-page":"20254","DOI":"10.1073\/pnas.1317052110","article-title":"Transcriptomic and biochemical analyses identify a family of chlorhexidine efflux proteins","volume":"110","author":"Hassan","year":"2013","journal-title":"Proc. Natl. Acad. Sci."},{"key":"ref17","doi-asserted-by":"publisher","first-page":"1179","DOI":"10.1099\/00207713-47-4-1179","article-title":"Discrimination of Acinetobacter genomic species by AFLP fingerprinting","volume":"47","author":"Janssen","year":"1997","journal-title":"Int. J. Syst. Bacteriol."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"17","DOI":"10.3390\/toxics8010017","article-title":"Concentration- and time-dependent effects of Benzalkonium chloride in human lung epithelial cells: necrosis, apoptosis, or epithelial mesenchymal transition","volume":"8","author":"Kim","year":"2020","journal-title":"Toxics"},{"key":"ref19","doi-asserted-by":"publisher","first-page":"1995","DOI":"10.1038\/s41564-023-01474-z","article-title":"Systematic analyses identify modes of action of ten clinically relevant biocides and antibiotic antagonism in Acinetobacter baumannii","volume":"8","author":"Li","year":"2023","journal-title":"Nat. Microbiol."},{"key":"ref20","doi-asserted-by":"publisher","first-page":"402","DOI":"10.1006\/meth.2001.1262","article-title":"Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) method","volume":"25","author":"Livak","year":"2001","journal-title":"Methods"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"2289769","DOI":"10.1080\/21505594.2023.2289769","article-title":"Pathogenicity and virulence of Acinetobacter baumannii: factors contributing to the fitness in healthcare settings and the infected host","volume":"15","author":"Lucidi","year":"2024","journal-title":"Virulence"},{"key":"ref22","doi-asserted-by":"publisher","first-page":"981","DOI":"10.1111\/1469-0691.12651","article-title":"Antimicrobial susceptibility testing in biofilm-growing bacteria","volume":"20","author":"Maci\u00e0","year":"2014","journal-title":"Clin. Microbiol. Infect."},{"key":"ref23","doi-asserted-by":"publisher","first-page":"95","DOI":"10.1186\/s13756-023-01290-4","article-title":"How biofilms change our understanding of cleaning and disinfection","volume":"12","author":"Maillard","year":"2023","journal-title":"Antimicrob. Resist. Infect. Control"},{"key":"ref24","doi-asserted-by":"publisher","first-page":"336","DOI":"10.3390\/antibiotics9060336","article-title":"Stilbenoids: a natural arsenal against bacterial pathogens","volume":"9","author":"Mattio","year":"2020","journal-title":"Antibiotics"},{"key":"ref25","doi-asserted-by":"publisher","first-page":"147","DOI":"10.1128\/CMR.12.1.147","article-title":"Antiseptics and disinfectants: activity, action, and resistance","volume":"12","author":"McDonnell","year":"1999","journal-title":"Clin. Microbiol. Rev."},{"key":"ref26","doi-asserted-by":"publisher","first-page":"e00377-19","DOI":"10.1128\/AEM.00377-19","article-title":"Benzalkonium chlorides: uses, regulatory status, and microbial resistance","volume":"85","author":"Merchel Piovesan Pereira","year":"2019","journal-title":"Appl. Environ. Microbiol."},{"key":"ref27","doi-asserted-by":"publisher","first-page":"1635","DOI":"10.3390\/antibiotics11111635","article-title":"Contribution of RND-type efflux pumps in reduced susceptibility to biocides in Acinetobacter baumannii","volume":"11","author":"Meyer","year":"2022","journal-title":"Antibiotics"},{"key":"ref28","doi-asserted-by":"publisher","first-page":"790263","DOI":"10.3389\/fmicb.2021.790263","article-title":"Inhibition of AdeB, AceI, and AmvA efflux pumps restores chlorhexidine and Benzalkonium susceptibility in Acinetobacter baumannii ATCC 19606","volume":"12","author":"Migliaccio","year":"","journal-title":"Front. Microbiol."},{"key":"ref29","doi-asserted-by":"publisher","first-page":"961","DOI":"10.3390\/antibiotics11070961","article-title":"Resveratrol reverts tolerance and restores susceptibility to chlorhexidine and benzalkonium in gram-negative bacteria, gram-positive bacteria and yeasts","volume":"11","author":"Migliaccio","year":"","journal-title":"Antibiotics"},{"key":"ref30","doi-asserted-by":"publisher","first-page":"274","DOI":"10.1086\/524736","article-title":"Chlorhexidine: expanding the armamentarium for infection control and prevention","volume":"46","author":"Milstone","year":"2008","journal-title":"Clin. Infect. Dis."},{"key":"ref31","doi-asserted-by":"publisher","first-page":"e111660","DOI":"10.1371\/journal.pone.0111660","article-title":"Characterisation of pellicles formed by Acinetobacter baumannii at the air-liquid Interface","volume":"9","author":"Nait Chabane","year":"2014","journal-title":"PLoS One"},{"key":"ref32","doi-asserted-by":"publisher","first-page":"736","DOI":"10.3390\/antibiotics11060736","article-title":"Disinfection strategies for Carbapenem-resistant Klebsiella pneumoniae in a healthcare facility","volume":"11","author":"Ni","year":"2022","journal-title":"Antibiotics"},{"key":"ref33","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1093\/jac\/dkg301","article-title":"Synergy, antagonism, and what the chequerboard puts between them","volume":"52","author":"Odds","year":"2003","journal-title":"J. Antimicrob. Chemother."},{"key":"ref34","doi-asserted-by":"publisher","first-page":"1919","DOI":"10.1093\/jac\/dkq195","article-title":"Molecular and functional characterization of a novel efflux pump, AmvA, mediating antimicrobial and disinfectant resistance in Acinetobacter baumannii","volume":"65","author":"Rajamohan","year":"","journal-title":"J. Antimicrob. Chemother."},{"key":"ref35","doi-asserted-by":"publisher","first-page":"228","DOI":"10.1093\/jac\/dkp427","article-title":"Novel role of Acinetobacter baumannii RND efflux transporters in mediating decreased susceptibility to biocides","volume":"65","author":"Rajamohan","year":"","journal-title":"J. Antimicrob. Chemother."},{"key":"ref36","doi-asserted-by":"publisher","first-page":"e0243082","DOI":"10.1371\/journal.pone.0243082","article-title":"Rescued chlorhexidine activity by resveratrol against carbapenem-resistant Acinetobacter baumannii via down-regulation of AdeB efflux pump","volume":"15","author":"Singkham-In","year":"2020","journal-title":"PLoS One"},{"key":"ref37","doi-asserted-by":"publisher","first-page":"e01313","DOI":"10.1128\/mBio.01313-14","article-title":"Defining gene-phenotype relationships in Acinetobacter baumannii through one-step chromosomal gene inactivation","volume":"5","author":"Tucker","year":"2014","journal-title":"mBio"},{"key":"ref38","doi-asserted-by":"publisher","first-page":"706","DOI":"10.3945\/an.115.011627","article-title":"Resveratrol: how much wine do you have to drink to stay healthy?","volume":"7","author":"Weiskirchen","year":"2016","journal-title":"Adv. Nutr."},{"key":"ref39","volume-title":"Bacterial pathogens of public health importance to guide research, development and strategies to prevent and control antimicrobial resistance","year":"2024"},{"key":"ref40","doi-asserted-by":"publisher","first-page":"174","DOI":"10.1016\/j.jhin.2007.02.016","article-title":"Resistance to disinfectants in epidemiologically defined clinical isolates of Acinetobacter baumannii","volume":"66","author":"Wisplinghoff","year":"2007","journal-title":"J. Hosp. Infect."},{"key":"ref41","doi-asserted-by":"publisher","first-page":"409","DOI":"10.1128\/CMR.00058-16","article-title":"Clinical and pathophysiological overview of Acinetobacter infections: a century of challenges","volume":"30","author":"Wong","year":"2017","journal-title":"Clin. Microbiol. Rev."},{"key":"ref42","doi-asserted-by":"publisher","first-page":"240","DOI":"10.3390\/antibiotics9050240","article-title":"PYED-1 inhibits biofilm formation and disrupts the preformed biofilm of Staphylococcus aureus","volume":"9","author":"Vollaro","year":"2020","journal-title":"Antibiotics"},{"key":"ref43","doi-asserted-by":"publisher","first-page":"e00309-15","DOI":"10.1128\/mBio.00309-15","article-title":"Contribution of resistance-nodulation-cell division efflux systems to antibiotic resistance and biofilm formation in Acinetobacter baumannii","volume":"6","author":"Yoon","year":"2015","journal-title":"mBio"},{"key":"ref44","doi-asserted-by":"publisher","first-page":"2359","DOI":"10.1128\/JB.00245-11","article-title":"Genome sequences of three Acinetobacter baumannii strains assigned to the multilocus sequence typing genotypes ST2, ST25, and ST78","volume":"193","author":"Zarrilli","year":"2011","journal-title":"J. Bacteriol."},{"key":"ref45","doi-asserted-by":"publisher","first-page":"106605","DOI":"10.1016\/j.ijantimicag.2022.106605","article-title":"Clinical characteristics, tolerance mechanisms, and molecular epidemiology of reduced susceptibility to chlorhexidine among Pseudomonas aeruginosa isolated from a teaching hospital in China","volume":"60","author":"Zheng","year":"2022","journal-title":"Int. J. Antimicrob. Agents"}],"container-title":["Frontiers in Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2024.1494772\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,12,16]],"date-time":"2024-12-16T10:50:49Z","timestamp":1734346249000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2024.1494772\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,16]]},"references-count":46,"alternative-id":["10.3389\/fmicb.2024.1494772"],"URL":"https:\/\/doi.org\/10.3389\/fmicb.2024.1494772","relation":{},"ISSN":["1664-302X"],"issn-type":[{"value":"1664-302X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,16]]},"article-number":"1494772"}}