Results for “AMMONIUM COMPOUNDS” — Page 62

PubMed2006

Antifungal characteristics of N,N'-hexamethylenebis (4-carbamoyl-1-decylpyridinium bromide).

A bis-quaternary ammonium compound (bis-QAC), N,N'-hexamethylenebis(4-carbamoyl-1decylpyridinium bromide) (D-38), exhibited a wide antifungal spectrum and a strong activity against sixteen strains of fungi including nine strains isolated from various kinds of food. The antifungal activity was higher than that of N-dodecylpyridinium Iodide, a typical mono-QAC, and that of the commonly used fungicide, 2-(4-thiazolyl) benzimidazole. The activity of D-38, however, was comparatively low when it was measured by the agar dilution method. It is considered that the hydrophobic D-38 molecules, having two long alkyl chains, interacted with the agar medium, and therefore showed lower activity results. On the other hand, the activity of D-38 against Aspergillus niger IFO 6342 was not significantly influenced by temperature, pH and the initial spore concentration. These results indicate that bis-QACs can exhibit a high antifungal activity whether or not the environmental conditions change.

Antifungal Agents↗

PubMed2003

Dibucaine inhibition of serum cholinesterase.

The dibucaine number (DN) was determined for serum cholinesterase (EC 3.1.1.8, SChE) in plasma samples. The ones with a DN of 79-82 were used, because they had the "usual" SChE variant. The enzyme was assayed colorimetrically by the reaction of 5,5'-dithiobis-[2-nitrobenzoic acid] (DTNB) with the free sulfhydryl groups of thiocholine that were produced by the enzyme reaction with butrylthiocholine (BuTch) or acetylthiocholine (AcTch) substrates, and measured at 412 nm. Dibucaine, a quaternary ammonium compound, inhibited SChE to a minimum within 2 min in a reversible manner. The inhibition was very potent. It had an IC(50) of 5.3 microM with BuTch or 3.8 microM with AcTch. The inhibition was competitive with respect to BuTch with a K(i) of 1.3 microM and a linear-mixed type (competitive/noncompetitive) with respect to AcTch with inhibition constants, K(i) and K(I) of 0.66 and 2.5 microM, respectively. Dibucaine possesses a butoxy side chain that is similar to the butryl group of BuTch and longer by an ethylene group from AcTch. This may account for the difference in inhibition behavior. It may also suggest the existence of an additional binding site, other than the anionic binding site, and of a hydrophobic nature.

Acetylthiocholine↗

PubMed1993

Efficacy of disinfectants against fungi isolated from skin and nail infections.

Commercial disinfectants classified as fungicides may not be effective against commonly encountered fungi within reasonable periods. Cell suspensions of clinical fungal isolates were exposed to use-dilutions of various disinfectants. Quaternary ammonium compounds, iodophors, and phenolics were not fungicidal against all test fungi within 60 min of exposure. Trichophyton mentagrophytes, Epidermophyton floccosum, and Aspergillus fumigatus were among the more resistant fungi. Disinfectants that possess low-level activity should not be used for disinfection of medical instruments that come in contact with the patient. The only reliable and safe measure is to use high-level disinfectants such as the glutaraldehydes, which are fungicidal in 15 to 30 min.

Disinfectants↗

PubMed1998

Change of biotransformation steps of formaldehyde cycle in water-melon plants after infection with Fusarium oxysporum.

Recent experiments indicate that the measurable formaldehyde (HCHO) level is considerably elevated in the parts of water-melon plants immediately after a nonlethal infection with Fusarium oxysporum f. sp. niveum. At the same time the level of some quaternary ammonium compounds (N(epsilon)-trimethyl-L-lysine, choline) as potential HCHO generators (gene products) is considerably decreased. That is probably due to the fact that the alarm reaction phase of this biotic stress syndrome includes an intensive demethylation process. It has been proved that HCHO may play a role in dynamic methylation-demethylation processes that also may include the methylation of biotic stress proteins. In this paper we report on qualitative and quantitative changes in the biotransformation steps of the formaldehyde cycle in different parts of the water-melon plant after nonlethal infection (biotic stress) with Fusarium. In consequence of the infection identical quantitative changes, but to a different degree, of the compounds examined are observable in both varieties. The connections resulting from the depiction of the time-dependent quantitative changes of the measured methylated compounds due to infection show a picture similar to that of Selye's stress syndrome model.

Biotransformation↗

PubMed2000

Occupational skin diseases among the nurses in the region of Lódź.

We examined 223 nurses from the Lódź region, referred to the Nofer Institute of Occupational Medicine in 1995-99 because of suspected occupational dermatoses. The diagnosis of contact allergy was based on the positive results of patch tests, and immediate allergy to common allergens and latex on the results of prick tests, as well as on the determinations of specific IgE antibodies. Contact allergy was diagnosed in 66.4% of nurses. The most frequent sensitisers were quaternary ammonium compounds (benzalkonium) (23.8%), nickel (21.5%) and formaldehyde (20.6%); allergy was somewhat less frequently caused by thimerosal (14.3%), fragrances (12.1%), glutaraldehyde (10.8%), cobalt (9.9%), thiurams (6.7%) or glyoxal (4.9%). Allergy to rubber was diagnosed in 40 patients (17.9%), including 25 cases of immediate allergy to latex, 8 cases of contact dermatitis from thiuram rubber curing accelerators, and 7 cases of mixed allergy. It has been concluded that the contact with disinfectants (40.8% of allergic nurses), metals (30.9%) and rubber (17.9%) was the most frequent source of allergy in this group of medical personnel.

Adult↗

PubMedDate not supplied

In vitro effect of ethylenediaminetetraacetic acid-Tris on the efficacy of hatchery disinfectants.

Solutions of ethylenediaminetetraacetic acid (EDTA)-Tris showed synergistic or additive effects on gram-negative bacteria when combined with hatchery disinfectants consisting of phenol and detergent (Magnaphen-100), quaternary ammonium compound (QAC) and glutaraldehyde (Synergize), QAC (BioSentry 904), and hydrogen peroxide. The gram-positive bacteria reacted less favorably, with reaction mixtures showing all three levels of potentiation (synergistie, additive, and antagonistic). Combinations of EDTA-Tris and a commercial glutaraldehyde solution (Glutracide), when mixed with the test organisms, showed mostly antagonistic effects. Solutions of EDTA-Tris decreased the concentration of hatchery disinfectants required for bacterial killing by 75% in those situations in which synergistic potentiation occurred. EDTA-Tris is nontoxic to 12-day-old embryos. Serial passage of the test organisms in solutions of EDTA-Tris did not result in the development of resistant forms.

Animal Husbandry↗

PubMedDate not supplied

[Benzalkonium chloride: unacceptable to sterilize or disinfect medical or dental instruments].

OBJECTIVE: To compare the sporicidal activity of benzalkonium chloride (BKC) with that of glutaraldehyde. MATERIAL AND METHODS: A comparative study was conducted at the microbiology laboratory of Facultad de Odontología, Universidad Nacional Autónoma de México. Bacillus subtilis ATCC 9372 spores were exposed to these germicides (1 spore x mL) on a 0.22 mm filter. After completing the contact time the spores were washed and the filters were incubated on nutrient agar for 72 h at 37 degrees C. RESULTS: BKC did not eliminate B. subtilis spores at the concentration used, not even after increasing contact time to 15 h (900-fold the recommended time). Two percent glutaraldehyde destroyed spores only after 10 h of contact. Urea and sodium chloride showed no sporicidal activity. CONCLUSIONS: The results confirm that BKC lacks sporicidal activity and confirm that this quaternary ammonium compound is not able to "sterilize" or "disinfect" medical and dental instruments.

Anti-Infective Agents, Local↗

PubMed2002

Active efflux, a common mechanism for biocide and antibiotic resistance.

Energy-driven drug efflux systems are increasingly recognized as mechanisms of antibiotic resistance. Chromosomally located or acquired by bacteria, they can either be activated by environmental signals or by a mutation in a regulatory gene. Two major categories exist: those systems energized by proton motive force and those dependent on ATP. The pumps may have limited or broad substrates, the so-called multiple drug resistance pumps, which themselves form a number of related families. The multiple antibiotic resistance (mar) locus and mar regulon in Escherichia coli and other members of the Enterobacteriaceae is a paradigm for a generalized response locus leading to increased expression of efflux pumps. One such pump, the AcrAB pump extrudes biocides such as triclosan, chlorhexidine and quaternary ammonium compounds as well as multiple antibiotics. In Pseudomonas aeruginosa, a number of multidrug efflux pumps export a broad range of substrates. Since bacteria expressing these pumps thwart the efficacy of both kinds of therapeutic agents which control infectious diseases -- biocides which prevent transmission of infectious disease agents and antibiotics which treat and cure infectious diseases -- they are of particular concern. The prudent use of antibiotics and biocides will guard against the selection and propagation of drug-resistant mutants and preserve the efficacy of these valuable anti-infective agents.

Anti-Bacterial Agents↗

PubMed2002

Biocide use in the food industry and the disinfectant resistance of persistent strains of Listeria monocytogenes and Escherichia coli.

AIMS: The aims of the project were threefold: to survey the use of disinfectants in the UK food industry; to assess the product and environmental microflora of selected food factories for the persistence of Listeria monocytogenes and Escherichia coli; and to determine the disinfectant resistance of any persistent strains. METHODS AND RESULTS: A survey of the use of disinfectants in the UK food industry was undertaken in which a total of 40 sites were visited and a further 77 postal questionnaires were returned from farms, food manufacture, food transport and food retail sites. Quaternary ammonium compounds (QACs) were predominantly used, applied in small volumes as a mist. Approximately 30,000 samples from the product and environment of five chilled food factories were examined for L. monocytogenes and E. coli over a 3 year period. A total of 181 L. monocytogenes and 176 E. coli isolates were ribotyped to yield 19 and 34 ribogroups, respectively. Some strains were isolated only from the product, a number only from the environment and others from both niches. Some strains were seen to be persistent for the duration of the sampling exercise (2-3 years). The most common L. monocytogenes and E. coli strains, together with two environmental L. monocytogenes strains, were assessed for any resistance to commercial disinfectants as compared with a laboratory L. monocytogenes disinfectant testing strain. The resistance of the L. monocytogenes and E. coli strains isolated from the factory were not significantly different from the laboratory control strain. CONCLUSIONS: Persistent strains of L. monocytogenes and E. coli are found in the UK food industry, though this persistence is not related to their increased susceptibility to the most commonly used disinfectants. SIGNIFICANCE AND IMPACT OF THE STUDY: The concept of a persistent microflora in food factories will have an impact on the future selection of suitable control options, including the use of biocides.

DNA Fingerprinting↗

PubMed2002

Introduction of biocides into clinical practice and the impact on antibiotic-resistant bacteria.

Biocides and other antimicrobial agents have been employed for centuries. Much later, iodine found use as a wound disinfectant, chlorine water in obstetrics, alcohol as a hand disinfectant and phenol as a wound dressing and in antiseptic surgery. In the early part of the twentieth century, other chlorine-releasing agents (CRAs), and acridine and other dyes were introduced, as were some quaternary ammonium compounds (QACs, although these were only used as biocides from the 1930s). Later still, various phenolics and alcohols, formaldehyde and hydrogen peroxide were introduced and subsequently (although some had actually been produced at an earlier date) biguanides, iodophors, bisphenols, aldehydes, diamidines, isocyanurates, isothiazolones and peracetic acid. Antibiotics were introduced clinically in the 1940s, although sulphonamides had been synthesized and used previously. After penicillin came streptomycin and other aminoglycosides-aminocyclitols, tetracyclines, chloramphenicol, macrolides, semi-synthetic beta-lactams, glycopeptides, lincosamides, 4-quinolones and diaminopyrimidines. Bacterial resistance to antibiotics is causing great concern. Mechanisms of such resistance include cell impermeability, target site mutation, drug inactivation and drug efflux. Bacterial resistance to biocides was described in the 1950s and 1960s and is also apparently increasing. Of the biocides listed above, cationic agents (QACs, chlorhexidine, diamidines, acridines) and triclosan have been implicated as possible causes for the selection and persistence of bacterial strains with low-level antibiotic resistance. It has been claimed that the chronological emergence of qacA and qacB determinants in clinical isolates of Staphylococcus aureus mirrors the introduction and usage of cationic biocides.

Anti-Bacterial Agents↗

PubMed2002

Susceptibility of antibiotic-resistant cocci to biocides.

Biocide resistance has hitherto been a poorly studied subject, possibly due to the belief that such resistance was rare and clinically insignificant. Various recent findings, however, have underlined the importance of biocide resistance as a clinically relevant phenomenon. Outbreaks of biocide-resistant organisms in hospitals have been described and the genetic mechanism for resistance to quaternary ammonium compounds (QACs) in Staphylococcus aureus has now been elucidated. Mycobacteria resistant to commonly used endoscope disinfectants are now commonly reported and have caused numerous adverse clinical events. Cross-resistance between triclosan and antituberculous drugs has been demonstrated in other strains of mycobacteria. This is related to a common mechanism of action. The work presented here describes studies into the biocide resistance of antibiotic-resistant cocci and attempts to create biocide-resistant strains in vitro. Strains of staphylococci (including methicillin-resistant Staph. aureus (MRSA)) and enterococci (including vancomycin-resistant enterococci (VRE)) had their susceptibility to biocides assayed using broth macro dilution methods and resistant strains were selected by serial subculture on biocide-containing media. Mutants were created with relative ease; for instance, triclosan minimal bactericidal concentrations (MBCs) increased from 0.002 to 3.12 mg l(-1). Some strains of MRSA which have intermediate resistance to glycopeptides were demonstrated to have decreased susceptibility to some biocides. Biocide resistance amongst enterococci was demonstrated although there was no clear correlation between biocide and antibiotic resistance. The exact mechanisms of resistance in these strains are still being studied but it is clear that biocide resistance is an important clinical phenomenon.

Anti-Infective Agents, Local↗

PubMed2002

Effect of solution parameters on the removal efficiency of humic substances by a reuse material.

This paper provides an overview of the ability of polypropylene (PPL), a synthetic polymeric adsorbent made from reused plastic material. The removal of humic substances (HS) in a solution pretreated with dedoxyltrimethylammoniumbromide (DDTMAB), a cationic quaternary ammonium compound (QAC), was studied under various conditions. The removal of HS was achieved in its solute complexed form but also as suspended solids. The conditions of the HS solution, which fluctuation was suspected to have an impact on the performance of the adsorbent, were tested. The parameters investigated included the pH, the initial concentration of the surfactant, and the presence of suspended solids in solution. The results of the laboratory scale experiments showed that PPL removal efficiency of HS is strongly pH dependant with higher removal achieved at pH greater than 7. However, the shift for pH above 7 induced an increase in the optimum doses of DDTMAB as more and more deprotonated HS become available to react with DDTMAB. Ionic strength did have the opposite effect: the increase of ionic strength by addition of NaCl decreased PPL removal of HS.

Adsorption↗

PubMed2002

[In vitro germicide action of disinfectant products used in the food industry].

There is a wide offer of disinfectant products, for the food industry, available in the market, such as chlorine, iodine and quaternary ammonium compounds and their respective derivatives. However, new alternative products have emerged, for instance grapefruit seed extract, and peracetic and lactic acids. The present study was carried out in order to analyze in vitro the germicide effect, from the grapefruit seed extract (400 ppm), peracetic acid (2000 ppm) and lactic acid (20,000 ppm) at the manufacturer recommended action time, and other additional times. The germicide effect was tested against microorganisms such as Escherichia coli, Staphylococcus aureus, Streptococcus faecalis and Pseudomonas aeruginosa. In each case, the death kinetic was determined through the evaluation of the germicide effect (%), specific death rate (t-1) and the decimal reduction time (min). From the evaluated products, the best germicidal effect at the manufacturer conditions was reached by peracetic acid (2000 ppm) at 1 min, which presented the lower decimal reduction times compared with the other tested microorganisms. Generally speaking, Gram positive microorganisms showed a greater sensibility to the disinfectant action.

Disinfectants↗

PubMed2002

Active efflux, a common mechanism for biocide and antibiotic resistance.

Energy-driven drug efflux systems are increasingly recognized as mechanisms of antibiotic resistance. Chromosomally located or acquired by bacteria, they can either be activated by environmental signals or by a mutation in a regulatory gene. Two major categories exist: those systems energized by proton motive force and those dependent on ATP. The pumps may have limited or broad substrates, the so-called multiple drug resistance pumps, which themselves form a number of related families. The multiple antibiotic resistance (mar) locus and mar regulon in Escherichia coli and other members of the Enterobacteriaceae is a paradigm for a generalized response locus leading to increased expression of efflux pumps. One such pump, the AcrAB pump extrudes biocides such as triclosan, chlorhexidine and quaternary ammonium compounds as well as multiple antibiotics. In Pseudomonas aeruginosa, a number of multidrug efflux pumps export a broad range of substrates. Since bacteria expressing these pumps thwart the efficacy of both kinds of therapeutic agents which control infectious diseases--biocides which prevent transmission of infectious disease agents and antibiotics which treat and cure infectious diseases--they are of particular concern. The prudent use of antibiotics and biocides will guard against the selection and propagation of drug-resistant mutants and preserve the efficacy of these valuable anti-infective agents.

Anti-Bacterial Agents↗

PubMed2002

Biocide use in the food industry and the disinfectant resistance of persistent strains of Listeria monocytogenes and Escherichia coli.

AIMS: The aims of the project were threefold: to survey the use of disinfectants in the UK food industry; to assess the product and environmental microflora of selected food factories for the persistence of Listeria monocytogenes and Escherichia coli; and to determine the disinfectant resistance of any persistent strains. METHODS AND RESULTS: A survey of the use of disinfectants in the UK food industry was undertaken in which a total of 40 sites were visited and a further 77 postal questionnaires were returned from farms, food manufacture, food transport and food retail sites. Quaternary ammonium compounds (QACs) were predominantly used, applied in small volumes as a mist. Approximately 30,000 samples from the product and environment of five chilled food factories were examined for L. monocytogenes and E. coli over a 3 year period. A total of 181 L. monocytogenes and 176 E. coli isolates were ribotyped to yield 19 and 34 ribogroups, respectively. Some strains were isolated only from the product, a number only from the environment and others from both niches. Some strains were seen to be persistent for the duration of the sampling exercise (2-3 years). The most common L. monocytogenes and E. coli strains, together with two environmental L. monocytogenes strains, were assessed for any resistance to commercial disinfectants as compared with a laboratory L. monocytogenes disinfectant testing strain. The resistance of the L. monocytogenes and E. coli strains isolated from the factory were not significantly different from the laboratory control strain. CONCLUSIONS: Persistent strains of L. monocytogenes and E. coli are found in the UK food industry, though this persistence is not related to their increased susceptibility to the most commonly used disinfectants. SIGNIFICANCE AND IMPACT OF THE STUDY: The concept of a persistent microflora in food factories will have an impact on the future selection of suitable control options, including the use of biocides.

Anti-Bacterial Agents↗

PubMed2002

Introduction of biocides into clinical practice and the impact on antibiotic-resistant bacteria.

Biocides and other antimicrobial agents have been employed for centuries. Much later, iodine found use as a wound disinfectant, chlorine water in obstetrics, alcohol as a hand disinfectant and phenol as a wound dressing and in antiseptic surgery. In the early part of the twentieth century, other chlorine-releasing agents (CRAs), and acridine and other dyes were introduced, as were some quaternary ammonium compounds (QACs, although these were only used as biocides from the 1930s). Later still, various phenolics and alcohols, formaldehyde and hydrogen peroxide were introduced and subsequently (although some had actually been produced at an earlier date) biguanides, iodophors, bisphenols, aldehydes, diamidines, isocyanurates, isothiazolones and peracetic acid. Antibiotics were introduced clinically in the 1940s, although sulphonamides had been synthesized and used previously. After penicillin came streptomycin and other aminoglycosides-aminocyclitols, tetracyclines, chloramphenicol, macrolides, semi-synthetic beta-lactams, glycopeptides, lincosamides, 4-quinolones and diaminopyrimidines. Bacterial resistance to antibiotics is causing great concern. Mechanisms of such resistance include cell impermeability, target site mutation, drug inactivation and drug efflux. Bacterial resistance to biocides was described in the 1950s and 1960s and is also apparently increasing. Of the biocides listed above, cationic agents (QACs, chlorhexidine, diamidines, acridines) and triclosan have been implicated as possible causes for the selection and persistence of bacterial strains with low-level antibiotic resistance. It has been claimed that the chronological emergence of qacA and qacB determinants in clinical isolates of Staphylococcus aureus mirrors the introduction and usage of cationic biocides.

Anti-Bacterial Agents↗

PubMed2002

Susceptibility of antibiotic-resistant cocci to biocides.

Biocide resistance has hitherto been a poorly studied subject, possibly due to the belief that such resistance was rare and clinically insignificant. Various recent findings, however, have underlined the importance of biocide resistance as a clinically relevant phenomenon. Outbreaks of biocide-resistant organisms in hospitals have been described and the genetic mechanism for resistance to quaternary ammonium compounds (QACs) in Staphylococcus aureus has now been elucidated. Mycobacteria resistant to commonly used endoscope disinfectants are now commonly reported and have caused numerous adverse clinical events. Cross-resistance between triclosan and antituberculous drugs has been demonstrated in other strains of mycobacteria. This is related to a common mechanism of action. The work presented here describes studies into the biocide resistance of antibiotic-resistant cocci and attempts to create biocide-resistant strains in vitro. Strains of staphylococci (including methicillin-resistant Staph. aureus (MRSA)) and enterococci (including vancomycin-resistant enterococci (VRE)) had their susceptibility to biocides assayed using broth macro dilution methods and resistant strains were selected by serial subculture on biocide-containing media. Mutants were created with relative ease; for instance, triclosan minimal bactericidal concentrations (MBCs) increased from 0.002 to 3.12 mg l(-1). Some strains of MRSA which have intermediate resistance to glycopeptides were demonstrated to have decreased susceptibility to some biocides. Biocide resistance amongst enterococci was demonstrated although there was no clear correlation between biocide and antibiotic resistance. The exact mechanisms of resistance in these strains are still being studied but it is clear that biocide resistance is an important clinical phenomenon.

Anti-Bacterial Agents↗

PubMed2003

[Effect of disinfectants on surface hydrophobicity and mobility in Salmonella enterica serovar Typhimurium DT104].

The paper evaluated antibacterial efficacy of 12 disinfectants on the basis of quaternary ammonium compounds (KAZ) on the isolates of Salmonella enterica serovar Typhimurium of the definitive phage type 104 (DT104). One isolate--5551/99--represented the multiresistant phenotype, resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), and tetracycline (T). The second isolate--577/99--was sensitive to all antibiotics tested. The present study further examined the capability of sub-MIC concentrations of disinfectants to intervene into surface hydrophobicity and motility of the strains tested. The results showed that all disinfectants under study exhibited high antibacterial activity. It is of interest that the isolate resistant to antibiotics was more sensitive to disinfectants in comparison with the isolate resistant to antibiotics. The most effective substances against strain 5551/99 (R-type) were Sokrena, Triquart, Hexaquart plus, ID213, and Microbac forte, and those most effective against strain 577/99 (S-type) were Benzalkonium chloride and Hexaquart plus (MIC 0.09-0.19 microliter/ml). Surface hydrophobicity of both tested strains after the action of sub-MIC (1/16, 1/8, 1/4 of MIC) of disinfectants was not influenced in a more marked way. In the case of strain 5551/99, the highest percentage of inhibition of adherence to xylene, to 69.5% versus the control, was produced by 1/4 of MIC of the substance Triquart and, in the whole concentration range, by the substance Microbac forte. After the action of most substances to strain 577/99, stimulation of adherence took place. Only substance ID213 induced inhibition of adherence in the whole concentration range. The salt-aggregative capabilities of both strains were not influenced in a more marked way. The only exceptions were the action of 1/4 of MIC of the substances Cetrimid, Sokrena, ID212, Forten, and 1/8 of MIC of Hexaquart S on strain 577/99, where a decrease in hydrophobicity was observed. A moderate inhibition of motility was found after the action of 1/4 of MIC of Benzalkonium chloride (to 87.5%) and A.D.L. 007 (to 85.2%) on strain 5551/99. In the case of sensitive isolate 577/99, the most markedly manifested inhibition effect was that of Sokrena within the whole concentration range and that of 1/4 of MIC ID213. The results can be used in the selection of a suitable disinfectant for decontamination of solid surfaces. The effect of substances under study on surface hydrophobicity and motility of the important, food-transferred pathogen in the sense of inhibition or stimulation points out to intervention into its pathogenic potential.

Bacterial Adhesion↗