Background: This is the first report testing the antibiotic resistance-modifying activity of Mentha arvensis. Methods: In this study an ethanol extract of M. arvensis L. and chlorpromazine were tested for their antimicrobial activity alone or in combination with conventional antibiotics against strains of Escherichia coli. Results: The growth of two E. coli strains tested was not inhibited by the extract. The minimum inhibitory concentration and minimal bactericide concentration values were ≧1 mg/ml for both strains of E. coli used. A potentiating effect of this extract on gentamicin was demonstrated. Similarly, there was a potentiating effect of chlorpromazine on kanamycin, amikacin and tobramycin, indicating the involvement of an efflux system in the resistance to these aminoglycosides. Conclusions: It is therefore suggested that extracts from M. arvensis could be used as a source of plant-derived natural products with resistance-modifying activity, such as in the case of gentamicin, constituting a new weapon against bacterial resistance to antibiotics, as with chlorpromazine.
Cystic fibrosis is the most common and best known genetic disease involving a defect in transepithelial Cl- transport by mutations in the CF gene on chromosome 7, which codes for the cystic fibrosis transmembrane conductance regulator protein (CFTR). The most serious symptoms are observed in the lungs, augmenting the risk of bacterial infection. The objective of this review was to describe the bacterial pathogens colonizing patients with cystic fibrosis. A systematic search was conducted using the international bibliographic databanks SCIELO, HIGHWIRE, PUBMED, SCIRUS and LILACS to provide a useful and practical review for healthcare workers to make them aware of these microorganisms. Today, B. cepacia, P. aeruginosa and S. aureus are the most important infectious agents in cystic fibrosis patients. However, healthcare professionals must pay attention to emerging infectious agents in these patients, because they represent a potentially serious future problem. Therefore, these pathogens should be pointed out as a risk to these patients, and hospitals all over the world must be prepared to detect and combat these bacteria.
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 methicillinresistant Staphylococcus aureus -MRSA strain.
In an ongoing project to evaluate natural compounds isolated from plants from the Brazilian biodiversity as modulators of antibiotic resistance, kaempferol-3-O-beta-d-(6''-E-p-coumaroyl) glucopyranoside (tiliroside), isolated from Herissantia tiubae (Malvaceae) was investigated using the strain SA-1199B of Staphylococcus aureus, which overexpresses the norA gene encoding the NorA efflux protein which extrudes hydrophilic fluorquinolones and some biocides, such as benzalkonium chloride, cetrimide, acriflavine and ethidium bromide. The minimum inhibitory concentrations (MICs) of the antibiotics and biocides were determined by the microdilution assay in the absence and in the presence of sub-inhibitory concentration of tiliroside. Although tiliroside did not display relevant antibacterial activity (MIC = 256 microg/mL), it modulated the activity of antibiotics, i.e. in combination with antibiotics a reduction in the MIC was observed for norfloxacin (16-fold), ciprofloxacin (16-fold), lomefloxacin (four-fold) and ofloxacin (two-fold), and an impressive reduction in the MICs for the biocides (up to 128-fold). The results presented here represent the first report of a kaempferol glycoside as a putative efflux pump inhibitor in bacteria. The present finding indicates that H. tiubae (and broadly Malvaceae) could serve as a source of plant-derived natural products that modulate bacterial resistance, i.e. a source of potential adjuvants of antibiotics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.