Salmonella serovars sampled from meat products in Southern Spain (Andalucía) during the period 2002-2007 were analyzed in this study. The serovars most frequently detected (in order) were Typhimurium, Enteritidis, Derby, Anatum and Rissen. Isolates (n = 43) were tested for sensitivity to biocides, including the quaternary ammonium compounds benzalkonium chloride (BC), cetrimide (CT) and hexadec...

OBJECTIVE To evaluate disinfectants for domestic use for the presence of bacteria, identify them, and determine their tolerance level to benzalkonium chloride. METHODS Fifty-two samples of commercially available disinfectants for domestic use were acquired at random in the metropolitan area of São Paulo, Brazil, and analyzed to detect the presence of bacterial contaminants. The isolated organ...

OBJECTIVES To investigate the role of a putative small multidrug resistance transporter, annotated in Enterococcus faecalis V583 genome as EFA0010 (we will refer to this gene as qacZ), in decreased susceptibility to biocides. METHODS A derivative strain of V583, susceptible to erythromycin (V583ErmS), was complemented with pORI23 carrying the qacZ gene (strain EF-SAVE1). MICs of benzalkonium ...

Some aliphatic long-chain quaternary ammonium compounds and choline derivatives have been examined for their ability to induce pseudopodia from Amoeba proteus. The reaction involved in pseudopodium induction is believed to be between the quaternary nitrogen cations and polysaccharides on the cell surface. Not all of the carboxyl groups of the polysaccharide are involved in this reaction. The me...

The effects of a quaternary ammonium compound, ditallowdimethylammonium chloride (DTDMAC), on natural populations of bacteria and phytoplankton from the lower River Rhine were examined to estimate their sensitivity to the discharges of cationic surfactants in the river basin. In short-term experiments, significant decreases in the growth rate of bacterioplankton and in the photosynthetic rate o...

OBJECTIVE To investigate the effectiveness of a topically applied emulsion of an analgesic ammonium solution for the temporary treatment of pain associated with arthritis, tendinitis and bursitis. DESIGN 100 subjects in a single center, presenting with chronic pain associated with arthritis, tendinitis, or bursitis trialed against placebo in a double-blind cross-over protocol. MAIN OUTCOME ...

A simple and sensitive spectrophotometric assay for quaternary ammonium compounds (QACs) based on Dragendorff's reagent is described. Although not specific for a particular QAC, the assay allows for rapid survey of tissue for QAC content. A separation method for QACs in halophyte tissue containing high levels of cations was developed using ion exchange resins and ninhydrin to remove the amino a...

The scope of this study was the removal of ammonium by ion exchange from simulated wastewater. The study looks at the effect of organics upon ammonium ion exchange equilibrium uptake. The ion exchangers included a natural zeolite clinoptilolite, and two polymeric exchangers, Dowex 50w-x8, and Purolite MN500. The organic compounds studied included citric acid and a number of proteins. The tradit...

Effects of a quaternary ammonium compound (QAC) on the survival of adhering staphylococci on a surface were investigated using atomic force microscopy (AFM). Four strains with different minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) for the QAC were exposed to three different concentrations of the QAC in potassium phosphate buffer (0.5×, 1×, and 2× MBC) wh...

A series of soft quaternary ammonium antimicrobial agents, which are analogues to currently used quaternary ammonium preservatives such as cetyl pyridinium chloride and benzalkonium chloride, were synthesized. These soft analogues consist of long alkyl chain connected to a polar headgroup via chemically labile spacer group. They are characterized by facile nonenzymatic and enzymatic degradation...