title: Increasing of the aminoglicosyde antibiotic activity against a multidrug-resistant E. coli by Turnera ulmifolia L. and chlorpromazine.
abstract: In this study, an ethanol extract of Turnera ulmifolia L. (EETU) and chlorpromazine (CPZ) were tested for their antimicrobial activity alone or in combination with conventional antibiotics against two strains of Escherichia coli (E. coli). The growth of neither E. coli strain was inhibited by the extract. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration values were > or =1 mg/ml for both the strains of E. coli. However, the extract did increase the antimicrobial effects of amikacin, neomycin, and tobramycin. A similar effect of CPZ on amikacin, kanamycin, and tobramycin indicated the involvement of an efflux system in the resistance to these aminoglycosides. Results suggest that extracts from T. ulmifolia could be used as a plant-derived natural product with resistance-modifying activity, constituting a new weapon against bacterial resistance to antibiotics.
authors.affiliation: Laboratory of Research in Natural Products, Department of Biological Sciences, University of the Region of Cariri, Rua Cel. Antonio Luis 1161, Crato, CE, Brazil. hdmcoutinho@gmail.com
authors.forename: Henrique D M
authors.initials: HD
authors.lastname: Coutinho
authors.forename: José G M
authors.initials: JG
authors.lastname: Costa
authors.forename: Edeltrudes O
authors.initials: EO
authors.lastname: Lima
authors.forename: Vivyanne S
authors.initials: VS
authors.lastname: Falcão-Silva
authors.forename: José P
authors.initials: JP
authors.lastname: Siqueira-Júnior
mesh_terms: D000617:Aminoglycosides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002746:Chlorpromazine / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D004357:Drug Synergism; D004926:Escherichia coli / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D029647:Turnera / Q000737:chemistry*
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D002746:Chlorpromazine