Herbal therapy associated with antibiotic therapy: potentiation of the antibiotic activity against methicillin--resistant Staphylococcus aureus by Turnera ulmifolia L.
BACKGROUND
Staphylococcus genus is widely spread in nature being part of the indigenous microbiota of skin and mucosa of animal and birds. Some Staphylococcus species are frequently recognized as etiological agents of many animal and human opportunistic infections This is the first report testing the antibiotic resistance-modifying activity of Turnera ulmifolia against methicillin-resistant Staphylococcus aureus--MRSA strain.


METHODS
In this study an ethanol extract of Turnera ulmifolia L. and chlorpromazine were tested for their antimicrobial activity alone or in combination with aminoglycosides against an MRSA strain.


RESULTS
The synergism of the ethanol extract and aminoglycosides were verified using microdillution method. A synergistic effect of this extract on gentamicin and kanamycin was demonstrated. Similarly, a potentiating effect of chlorpromazine on kanamycin, gentamicin and neomycin, indicating the involvement of an efflux system in the resistance to these aminoglycosides.


CONCLUSIONS
It is therefore suggested that extracts from Turnera ulmifolia could be used as a source of plant-derived natural products with resistance-modifying activity, constituting a new weapon against the problem of bacterial resistance to antibiotics demonstrated in MRSA strains.
Coutinho
Henrique D M
HD
Laboratory of Research in Natural Products, Center of Biological Sciences and Health, University of the Region of Cariri, Crato, Brazil. hdmcoutinho@gmail.com
Costa
José G M
JG
Lima
Edeltrudes O
EO
Falcão-Silva
Vivyanne S
VS
Siqueira
José P
JP
D000617:Aminoglycosides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002746:Chlorpromazine / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D029647:Turnera
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D002746:Chlorpromazine