title: Antibacterial activity of three newly-synthesized chalcones & synergism with antibiotics against clinical isolates of methicillin-resistant Staphylococcus aureus.
abstract: OBJECTIVE
  Multidrug-resistance of methicillin-resistant Staphylococcus aureus (MRSA) is a serious therapeutical problem. Chalcones belong to a group of naturally occurring flavonoids, usually found in various plant species, and have potent antibacterial, antiviral and antifungal activities. The goal of this study was to evaluate the antibacterial effect of three newly-synthesized chalcones against clinical isolates of MRSA, and their synergism with β-lactam and non-β-lactam antibiotics.
  
  
  METHODS
  Antimicrobial activity of the three newly-synthesized chalcones was tested against 19 clinical isolates of MRSA and a laboratory control strain of MRSA (ATCC 43300). The synergism with β-lactams: cefotaxime (CFX), ceftriaxone (CTX), and non-β-lactam antibiotics: ciprofloxacin (CIP), gentamicin (GEN) and trimethoprim/sulphamethoxazole (TMP-SMX) was investigated by checkerboard method.
  
  
  RESULTS
  All evaluated compounds showed significant anti-MRSA activity with MIC values from 25-200 μg/ml. Observed synergism with antibiotics demonstrated that chalcones significantly enhanced the efficacy of CIP, GEN and TMP-SMX.
  
  
  CONCLUSIONS
  Our study demonstrated that three newly-synthesized chalcones exhibited significant anti-MRSA effect and synergism with non-β-lactam antibiotics. The most effective compound was 1,3-Bis-(2-hydroxy-phenyl)-propenone. Our results provide useful information for future research of possible application of chalcones in combination with conventional anti-MRSA therapy as promising new antimicrobial agents.
authors.affiliation: Departments of Microbiology & Immunology, University of Belgrade-Faculty of Pharmacy, Belgrade, Serbia.
authors.forename: Dragana D
authors.initials: DD
authors.lastname: Božić
authors.forename: Marina
authors.initials: M
authors.lastname: Milenković
authors.forename: Branka
authors.initials: B
authors.lastname: Ivković
authors.forename: Ivana
authors.initials: I
authors.lastname: Ćirković
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002439:Cefotaxime / Q000494:pharmacology; D002443:Ceftriaxone / Q000494:pharmacology; D047188:Chalcones / Q000138:chemical synthesis / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D002939:Ciprofloxacin / Q000494:pharmacology; D004357:Drug Synergism; D005839:Gentamicins / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D013055:Spectrophotometry, Infrared; D018709:Statistics, Nonparametric; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology
chemical_list: C000595693:1,3-bis-(2-hydroxy-phenyl)-propenone; D000900:Anti-Bacterial Agents; D047188:Chalcones; D005839:Gentamicins; D002939:Ciprofloxacin; D002443:Ceftriaxone; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D002439:Cefotaxime