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Leggett M, Setlow P, Sattar S, Maillard JY. Assessing the activity of microbicides against bacterial spores: knowledge and pitfalls. J Appl Microbiol 2016; 120:1174-80. [DOI: 10.1111/jam.13061] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/25/2015] [Accepted: 10/14/2015] [Indexed: 11/27/2022]
Affiliation(s)
- M.J. Leggett
- Cardiff School of Pharmacy and Pharmaceutical Sciences; Cardiff University; Cardiff UK
| | | | - S.A. Sattar
- Faculty of Medicine; University of Ottawa; Ottawa ON Canada
| | - J.-Y. Maillard
- Cardiff School of Pharmacy and Pharmaceutical Sciences; Cardiff University; Cardiff UK
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Bowman AS, Nolting JM, Nelson SW, Bliss N, Stull JW, Wang Q, Premanandan C. Effects of disinfection on the molecular detection of porcine epidemic diarrhea virus. Vet Microbiol 2015; 179:213-8. [PMID: 26072369 PMCID: PMC7127254 DOI: 10.1016/j.vetmic.2015.05.027] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/28/2015] [Accepted: 05/30/2015] [Indexed: 11/29/2022]
Abstract
Routine detection of porcine epidemic diarrhea virus (PEDV) is currently limited to RT-PCR but this test cannot distinguish between viable and inactivated virus. We evaluated the capability of disinfectants to both inactivate PEDV and sufficiently damage viral RNA beyond RT-PCR detection. Five classes of disinfectants (phenol, quaternary ammonium compound, sodium hypochlorite, oxidizing agent, and quaternary ammonium/glutaraldehyde combination) were evaluated in vitro at varying concentrations, both in the presence and absence of swine feces, and at three different temperatures. No infectious PEDV was recovered after treatment with evaluated disinfectants. Additionally, all tested disinfectants except for 0.17% sodium hypochlorite dramatically reduced qRT-PCR values. However, no disinfectants eliminated RT-PCR detection of PEDV across all replicates; although, 0.52%, 1.03% and 2.06% solutions of sodium hypochlorite and 0.5% oxidizing agent did intermittently produce RT-PCR negatives. To simulate field conditions in a second aim, PEDV was applied to pitted aluminum coupons, which were then treated with either 2.06% sodium hypochlorite or 0.5% oxidizing agent. Post-treatment surface swabs of the coupons tested RT-PCR positive but were not infectious to cultured cells or naïve pigs. Ultimately, viable PEDV was not detected following application of each of the tested disinfectants, however in most cases RT-PCR detection of viral RNA remained. RT-PCR detection of PEDV is likely even after disinfection with many commercially available disinfectants.
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Affiliation(s)
- Andrew S Bowman
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA.
| | - Jacqueline M Nolting
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA
| | - Sarah W Nelson
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA
| | - Nola Bliss
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA
| | - Jason W Stull
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA
| | - Qiuhong Wang
- Department of Veterinary Preventive Medicine, The Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA; Food Animal Health Research Program, Ohio Agricultural Research and Development Center, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, 1680 Madison Ave, Wooster, OH 44691, USA
| | - Christopher Premanandan
- Department of Veterinary Biosciences, The Ohio State University, 1925 Coffey Road, Columbus, OH, USA
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Pandey P, Packiyaraj MS, Nigam H, Agarwal GS, Singh B, Patra MK. Antimicrobial properties of CuO nanorods and multi-armed nanoparticles against B. anthracis vegetative cells and endospores. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:789-800. [PMID: 24991516 PMCID: PMC4077429 DOI: 10.3762/bjnano.5.91] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 05/06/2014] [Indexed: 05/21/2023]
Abstract
Two different kinds of CuO nanoparticles (NPs) namely CuO nanorods (PS2) and multi-armed nanoparticles (P5) were synthesized by wet and electrochemical routes, respectively. Their structure, morphology, size and compositions were characterized by SEM, EDX and XRD. The NPs demonstrated strong bactericidal potential against Bacillus anthracis cells and endospores. PS2 killed 92.17% of 4.5 × 10(4) CFU/mL B. anthracis cells within 1 h at a dose of 1 mg/mL. Whereas P5 showed a higher efficacy by killing 99.92% of 7 × 10(5) CFU/mL B. anthracis cells within 30 min at a dose of 0.5 mg/mL and 99.6% of 1.25 × 10(4) CFU/mL B. anthracis cells within 5 min at a dose of 2 mg/mL. More than 99% of spores were killed within 8 h with 2 mg/mL PS2 in LB media.
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Affiliation(s)
- Pratibha Pandey
- Electron Microscopy Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
| | - Merwyn S Packiyaraj
- Microbiology Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
| | - Himangini Nigam
- Microbiology Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
| | - Gauri S Agarwal
- Microbiology Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
| | - Beer Singh
- Electron Microscopy Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
- Protective Devices Division Defence R&D Establishment, New Campus, Jhansi Road, Gwalior, India
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Gnanadhas DP, Marathe SA, Chakravortty D. Biocides--resistance, cross-resistance mechanisms and assessment. Expert Opin Investig Drugs 2012; 22:191-206. [PMID: 23215733 DOI: 10.1517/13543784.2013.748035] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Antibiotic resistance in bacterial pathogens has increased worldwide leading to treatment failures. Concerns have been raised about the use of biocides as a contributing factor to the risk of antimicrobial resistance (AMR) development. In vitro studies demonstrating increase in resistance have often been cited as evidence for increased risks. It is therefore important to understand the mechanisms of resistance employed by bacteria toward biocides used in consumer products and their potential to impart cross-resistance to therapeutic antibiotics. AREAS COVERED In this review, the mechanisms of resistance and cross-resistance reported in the literature toward biocides commonly used in consumer products are summarized. The physiological and molecular techniques used in describing and examining these mechanisms are reviewed and application of these techniques for systematic assessment of biocides for their potential to develop resistance and/or cross-resistance is discussed. EXPERT OPINION The guidelines in the usage of biocides in household or industrial purpose should be monitored and regulated to avoid the emergence of any MDR strains. The genetic and molecular methods to monitor the resistance development to biocides should be developed and included in preclinical and clinical studies.
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Affiliation(s)
- Divya Prakash Gnanadhas
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research and Biosafety Laboratories, Indian Institute of Science, Bangalore 560012, India
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Oulé MK, Quinn K, Dickman M, Bernier AM, Rondeau S, De Moissac D, Boisvert A, Diop L. Akwaton, polyhexamethylene-guanidine hydrochloride-based sporicidal disinfectant: a novel tool to fight bacterial spores and nosocomial infections. J Med Microbiol 2012; 61:1421-1427. [PMID: 22871428 DOI: 10.1099/jmm.0.047514-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial spores are of continuing interest to the food and medical industries. In efforts to eliminate bacterial spore contamination, a number of sporicidal agents have been developed. Most of these compounds must be used carefully in very specific circumstances as they are toxic to humans. The sporicidal activity of Akwaton, a polyhexamethylene-guanidine hydrochloride (PHMGH)-based disinfectant, was tested against Bacillus subtilis spores. PHMGH is a colourless, odourless, non-corrosive and non-irritating antimicrobial biocide of the guanidine family. Spores suspended in distilled water and spores placed on solid surfaces (stainless steel and glass) were used to determine the log(10) reduction after exposure to varying concentrations of Akwaton. The minimum sporostatic concentration, the minimum sporicidal concentration and the time required for sporicidal activity corresponded to 0.06% (w/v), 0.08 % (w/v) and 8.5 min, respectively. Disinfectant concentrations of 0.24 % (w/v) and 0.44 % (w/v) killed all spores suspended in distilled water within 3 min and 90 s, respectively. The sporicidal activity against suspended spores was linearly dependent with respect to the concentration of PHMGH and contact time (y(3 min) = 40x-1.6 and y(90 s) = 20x-0.8 thus y(3 min) = 2y(90 s)). Spores placed on surfaces were more resistant to the effect of the disinfectant and the positive linear correlation between the sporicidal activity and concentration was not observed. The concentration required to kill all spores placed on a surface (stainless steel or glass) corresponded to 0.52 % (w/v) for 90 s of contact and 0.36 % (w/v) for 3 min. This study demonstrated that PHMGH is an effective sporicidal disinfectant with great potential for use in hospitals, laboratories, food industries and households.
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Affiliation(s)
- Mathias K Oulé
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Kelsi Quinn
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Michael Dickman
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Anne-Marie Bernier
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Sylvie Rondeau
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Danielle De Moissac
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Aurèle Boisvert
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
| | - Lamine Diop
- Department of Biological Science, Faculty of Science, Université de Saint-Boniface, 200 de la Cathédrale Avenue, Winnipeg, MB R2H 0H7, Canada
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Kampf G, Kramer A. Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs. Clin Microbiol Rev 2004; 17:863-93, table of contents. [PMID: 15489352 PMCID: PMC523567 DOI: 10.1128/cmr.17.4.863-893.2004] [Citation(s) in RCA: 416] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The etiology of nosocomial infections, the frequency of contaminated hands with the different nosocomial pathogens, and the role of health care workers' hands during outbreaks suggest that a hand hygiene preparation should at least have activity against bacteria, yeasts, and coated viruses. The importance of efficacy in choosing the right hand hygiene product is reflected in the new Centers for Disease Control and Prevention guideline on hand hygiene (J. M. Boyce and D. Pittet, Morb. Mortal. Wkly. Rep. 51:1-45, 2002). The best antimicrobial efficacy can be achieved with ethanol (60 to 85%), isopropanol (60 to 80%), and n-propanol (60 to 80%). The activity is broad and immediate. Ethanol at high concentrations (e.g., 95%) is the most effective treatment against naked viruses, whereas n-propanol seems to be more effective against the resident bacterial flora. The combination of alcohols may have a synergistic effect. The antimicrobial efficacy of chlorhexidine (2 to 4%) and triclosan (1 to 2%) is both lower and slower. Additionally, both agents have a risk of bacterial resistance, which is higher for chlorhexidine than triclosan. Their activity is often supported by the mechanical removal of pathogens during hand washing. Taking the antimicrobial efficacy and the mechanical removal together, they are still less effective than the alcohols. Plain soap and water has the lowest efficacy of all. In the new Centers for Disease Control and Prevention guideline, promotion of alcohol-based hand rubs containing various emollients instead of irritating soaps and detergents is one strategy to reduce skin damage, dryness, and irritation. Irritant contact dermatitis is highest with preparations containing 4% chlorhexidine gluconate, less frequent with nonantimicrobial soaps and preparations containing lower concentrations of chlorhexidine gluconate, and lowest with well-formulated alcohol-based hand rubs containing emollients and other skin conditioners. Too few published data from comparative trials are available to reliably rank triclosan. Personnel should be reminded that it is neither necessary nor recommended to routinely wash hands after each application of an alcohol-based hand rub. Long-lasting improvement of compliance with hand hygiene protocols can be successful if an effective and accessible alcohol-based hand rub with a proven dermal tolerance and an excellent user acceptability is supplied, accompanied by education of health care workers and promotion of the use of the product.
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Affiliation(s)
- Günter Kampf
- Bode Chemie GmbH & Co., Scientific Affairs, Melanchthonstrasse 27, 22525 Hamburg, Germany.
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McDonnell G, Russell AD. Antiseptics and disinfectants: activity, action, and resistance. Clin Microbiol Rev 1999; 12:147-79. [PMID: 9880479 PMCID: PMC88911 DOI: 10.1128/cmr.12.1.147] [Citation(s) in RCA: 2643] [Impact Index Per Article: 105.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Antiseptics and disinfectants are extensively used in hospitals and other health care settings for a variety of topical and hard-surface applications. A wide variety of active chemical agents (biocides) are found in these products, many of which have been used for hundreds of years, including alcohols, phenols, iodine, and chlorine. Most of these active agents demonstrate broad-spectrum antimicrobial activity; however, little is known about the mode of action of these agents in comparison to antibiotics. This review considers what is known about the mode of action and spectrum of activity of antiseptics and disinfectants. The widespread use of these products has prompted some speculation on the development of microbial resistance, in particular whether antibiotic resistance is induced by antiseptics or disinfectants. Known mechanisms of microbial resistance (both intrinsic and acquired) to biocides are reviewed, with emphasis on the clinical implications of these reports.
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Affiliation(s)
- G McDonnell
- STERIS Corporation, St. Louis Operations, St. Louis, Missouri 63166, USA.
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Knott AG, Russell AD. Effects of chlorhexidine gluconate on the development of spores of Bacillus subtilis. Lett Appl Microbiol 1995; 21:117-20. [PMID: 7639992 DOI: 10.1111/j.1472-765x.1995.tb01021.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of sublethal concentrations of the membrane-active agent chlorhexidine gluconate (CHG) on the growth rate and sporulation of Bacillus subtilis vegetative MB2 cells have been investigated. CHG increased the mean generation time (Mgt) of vegetative cells in casein medium. It also affected spore development: as CHG concentrations increased, spore index (SI) values decreased and sensitivity to both toluene and heat increased.
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Affiliation(s)
- A G Knott
- Welsh School of Pharmacy, University of Wales College of Cardiff, UK
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9
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Jones DS, Loftus AM, Gorman SP. Physical factors affecting the sporicidal activity of chlorhexidine gluconate. Int J Pharm 1995. [DOI: 10.1016/0378-5173(94)00409-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Bryce EA, Smith JA, Tweeddale M, Andruschak BJ, Maxwell MR. Dissemination of Bacillus cereus in an intensive care unit. Infect Control Hosp Epidemiol 1993; 14:459-62. [PMID: 8376735 DOI: 10.1086/646779] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To report the contamination of ventilator equipment with Bacillus cereus and to outline the measures taken to trace the source of the organism. DESIGN A prospective survey of all intensive care unit patients who were culture-positive for B cereus and obtaining of environmental cultures of the cleaning and assembly area of the respiratory services division between October 1991 and September 1992. SETTING AND PATIENTS Ventilated patients from a 16-bed medical and surgical intensive care unit (ICU) in a 1,000-bed adult tertiary care hospital. INTERVENTIONS AND RESULTS From October 1991 to April 1992, B cereus colonized the ventilator circuitry of patients in the ICU. One of two washer/decontaminators in the cleaning and assembly area of the respiratory services division was found to yield the microorganism consistently from the water intake port. The design of the machine precluded easy decontamination of the port with 2% glutaraldehyde and a second outbreak occurred. Following the second outbreak, aqueous chlorhexidine in a final concentration of 0.05% was added to the first of two pasteurization cycles in an attempt to achieve sporicidal activity. This ended the outbreak. Sixty-two patients became colonized with the organism including two with nonfatal Bacillus sepsis and one death due to pneumonia associated with the organism. CONCLUSION This experience emphasizes the importance of obtaining cultures of machine parts to identify the source of contamination and thereby direct control measures. Use of chlorhexidine gluconate at high temperatures effectively eradicated B cereus from ventilator circuitry in a practical and cost-effective manner.
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Affiliation(s)
- E A Bryce
- Division of Medical Microbiology, Vancouver General Hospital, British Columbia, Canada
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Gorman S, Jones D, Loftus A. The synergistic effect of direct and indirect ultrasonic energy and chlorhexidine gluconate on spores of Bacillus subtilis. Int J Pharm 1990. [DOI: 10.1016/0378-5173(90)90017-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rönner U, Husmark U, Henriksson A. Adhesion of bacillus spores in relation to hydrophobicity. THE JOURNAL OF APPLIED BACTERIOLOGY 1990; 69:550-6. [PMID: 2292519 DOI: 10.1111/j.1365-2672.1990.tb01547.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The adhesion of spores of five different Bacillus species to solid surfaces of different hydrophobicity was evaluated. The spore surface hydrophobicity was measured using hydrophobic interaction chromatography (HIC). A large variation in hydrophobicity was found among the spores of the different species tested. The degree of adhesion of spores to the solid surfaces was consistent with the results obtained using the HIC method. The most hydrophobic spores, according to the HIC method, adhered in a much larger extent to the hydrophobic surfaces. Furthermore, spores generally adhered to a greater extent to hydrophobic and hydrophilic surfaces than did the vegetative cells.
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Affiliation(s)
- U Rönner
- Swedish Institute for Food Research, Göteborg
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13
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Shaker L, Dancer B, Russell A, Furr J. Emergence and development of chlorhexidine resistance during sporulation ofBacillus subtilis168. FEMS Microbiol Lett 1988. [DOI: 10.1111/j.1574-6968.1988.tb02971.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Shaker LA, Furr JR, Russell AD. Mechanism of resistance of Bacillus subtilis spores to chlorhexidine. THE JOURNAL OF APPLIED BACTERIOLOGY 1988; 64:531-9. [PMID: 3139612 DOI: 10.1111/j.1365-2672.1988.tb02444.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Chlorhexidine diacetate (CHA) was rather more sporicidal at 20 degrees C to urea-dithreitol-sodium lauryl sulphate (UDS)-treated spores of Bacillus subtilis NCTC 8236 than to urea-dithiothreitol (UDT)-treated or normal (untreated) spores. UDS spores adsorbed more CHA from solution than did the other two forms. No differences in hydrophobicity, as determined by hydrophobic interaction chromatography (HIC) or bacterial adherence to hydrocarbon (BATH), could be detected between the three spore types. Germinating spores took up much less CHA than did outgrowing spores. Germinating cells were considerably more hydrophobic, as measured by the BATH technique, than outgrowing cells or normal spores. Chlorhexidine diacetate increased the apparent hydrophobicity of the two latter forms, but this effect could be partially reversed by subsequent exposure to a non-ionic surfactant.
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Affiliation(s)
- L A Shaker
- Pharmaceutical Microbiology Research Laboratory, Welsh School of Pharmacy, University of Wales Institute of Science and Technology, Cardiff, UK
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Gorman SP, Jones DS, Loftus AM. The sporicidal activity and inactivation of chlorhexidine gluconate in aqueous and alcoholic solution. THE JOURNAL OF APPLIED BACTERIOLOGY 1987; 63:183-8. [PMID: 3115938 DOI: 10.1111/j.1365-2672.1987.tb02701.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The sporicidal activity of chlorhexidine gluconate in aqueous and alcoholic solution against spores of Bacillus subtilis was examined over a broad temperature range. Activity was not observed at 20 degrees C even with concentrations as high as 10% chlorhexidine. Temperatures of 37 degrees-70 degrees C in combination with such high concentrations were required for reductions in spore viability. No viable spores were recoverable after 4 h contact at 55 degrees C with 10% aqueous chlorhexidine and none after 3 h contact with the alcoholic solution. Because of the high concentrations necessary for activity and the possibility of sporostasis occurring from inefficient chlorhexidine inactivation, existing inactivation systems were examined and modified to obtain satisfactory results. The spores of other Bacillus species examined (B. cereus, B. megaterium and B. stearothermophilus) proved to be considerably less resistant than those of B. subtilis. Presence of organic matter had little effect on the activity.
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Affiliation(s)
- S P Gorman
- Department of Pharmacy, Queen's University of Belfast, UK
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