Antibacterial activity against β- lactamase producing Methicillin and Ampicillin-resistants Staphylococcus aureus: Fractional Inhibitory Concentration Index (FICI) determination

Ann Clin Microbiol Antimicrob. 2012 Jun 20:11:18. doi: 10.1186/1476-0711-11-18.

Abstract

Background: The present study reports the antibacterial capacity of alkaloid compounds in combination with Methicillin and Ampicillin-resistants bacteria isolated from clinical samples. The resistance of different bacteria strains to the current antibacterial agents, their toxicity and the cost of the treatment have led to the development of natural products against the bacteria resistant infections when applied in combination with conventional antimicrobial drugs.

Method: The antibacterial assays in this study were performed by using inhibition zone diameters, MIC, MBC methods, the time-kill assay and the Fractional Inhibitory Concentration Index (FICI) determination. On the whole, fifteen Gram-positive bacterial strains (MRSA/ARSA) were used. Negative control was prepared using discs impregnated with 10 % DMSO in water and commercially available Methicillin and Ampicillin from Alkom Laboratories LTD were used as positive reference standards for all bacterial strains.

Results: We noticed that the highest activities were founded with the combination of alkaloid compounds and conventional antibiotics against all bacteria strains. Then, results showed that after 7 h exposition there was no viable microorganism in the initial inoculums.

Conclusion: The results of this study showed that alkaloid compounds in combination with conventional antibiotics (Methicillin, Ampicillin) exhibited antimicrobial effects against microorganisms tested. These results validate the ethno-botanical use of Cienfuegosia digitata Cav. (Malvaceae) in Burkina Faso. Moreover, this study demonstrates the potential of this herbaceous as a source of antibacterial agent that could be effectively used for future health care purposes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / isolation & purification
  • Alkaloids / pharmacology*
  • Ampicillin / pharmacology*
  • Ampicillin Resistance / drug effects
  • Anti-Bacterial Agents / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / antagonists & inhibitors
  • Bacterial Proteins / metabolism
  • Biological Assay
  • Drug Synergism
  • Malvaceae / chemistry*
  • Methicillin / pharmacology*
  • Methicillin Resistance / drug effects
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Methicillin-Resistant Staphylococcus aureus / growth & development
  • Microbial Sensitivity Tests / methods
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology
  • beta-Lactamase Inhibitors*
  • beta-Lactamases / metabolism

Substances

  • Alkaloids
  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Plant Extracts
  • beta-Lactamase Inhibitors
  • Ampicillin
  • beta-Lactamases
  • Methicillin