No description available.

No description available.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

An increase in the number of bacteria resistant to most of the antibiotics or biocides in common use is a problem faced by industries and the community at large. More bacteria are resistant to moderate levels of biocides, with the bacteria in biofilms being the most difficult to control. High levels of biocides are used and this has detrimental effects on the environment, as biocides are toxic to humans, being carcinogenic, corrosive and producing intolerable odours. Electrochemical activation technology provides an alternative way of controlling microorganisms. ECA water was shown in other countries to have antimicrobial properties. Anolyte, the positively charged solution is benign to fumes and corrosion caused by other biocides. Since anolyte is eco-friendly and present no problems to the environment, it provides a good alternative for controlling microorganisms instead of chemical control. The minimum inhibitory concentration (MIC) of anolyte and its antimicrobial properties against different microorganisms in suspension was evaluated. The I: 1 0 and neat anolyte gave a 100% kill of all organisms tested while 1 :20 dilution gave variable killing percentages ranging from 31 % to 100%. Minimum inhibitory concentration was found to be 20% for most Gram positives and 50% for most Gram negatives. Anolyte did have some antimicrobial properties with MIC differing amongst different organisms. Biofilm control using different concentrations of anolyte and sodium hypochlorite was evaluated. Neat and 1: 10 anolyte removed biofilm while 1: 100 did not have effect on biofilm. The 100 and 300 ppm sodium hypochlorite were effective in removing the biofilm while 10, 25 and 50 ppm could not remove it. Hand wash trials and hospital disinfection using anolyte resulted in a decrease in the number of cfu/25cm3 after treatment. Effective disinfection of hands and hospital equipment was achieved. Different surfaces in a milking parlour were treated with anolyte to test its suitability to disinfect a milking parlour. High numbers of microorganisms and spreaders were observed from the plates before the surfaces were cleaned with anolyte. All spreaders were identified as sporeformers. Results were generally better when anolyte was used as a disinfectant, being able to eliminate spreaders as well. Treatment of chicken carcasses with anolyte to evaluate its effect on their shelf life was also tested. The number of colony forming units on chicken carcasses decreased after treatment of the carcasses with anolyte. Anolyte is therefore a naturally safe disinfectant that could be used in most fields including water distribution systems and industries for biofilm control, hospitals for minimising cross infection, food industries for increasing quality and shelf life of food and also in households for washing hands. / Dissertation (MSc (Microbiology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted

MSc (Med), Clinical Microbiology and Infectious Diseases, Faculty of Health Sciences, University of the Witwatersrand / The goal of infection control is to minimize the risk of exposure to potential pathogens and to create a safe working environment in which patients can be treated. Use of disinfectants in is an integral part of infection control. The rate of killing of microorganisms depends upon the type, concentration and time of exposure of the killing agent (disinfectant). Chlorinated compounds are frequently used in healthcare settings but chlorine dioxide has only been used in industries on a large scale. Aseptrol® is newly developed slow release chlorine dioxide and noncorrosive formula which can be used on a smaller scale basis. This study assessed the antimicrobial properties of Aseptrol® (48ppm and 24ppm) in comparison with previously used sodium dichloroisocyanurate containing formula, Presept® (10 000ppm). Both disinfectants killed more susceptible bacteria, such as Staphylococcus aureus, Pseudomonas. aeruginosa and Streptococcus mutans within 30 seconds and proved to be fungicidal by killing Candida albicans within 30 seconds. Aseptrol® and Presept® killed less susceptible mycobacteria such as Mycobacterium tuberculosis, Mycobacterium avium subsp. avium and blood borne organism Hepatitis B virus within 30 seconds. Highly resistant B. subtilis spores were killed in 2 and 2.5 minutes by Aseptrol® and Presept® respectively. Although manufacturers recommend that the disinfectant solutions should be prepared daily, when the shelf-life of prepared solutions stored in screw cap bottles was studied, the results showed that Aseptrol® can be effectively used for 27 day and Presept® for more than 37 days. The goal of infection control is to minimize the risk of exposure to potential pathogens and to create a safe working environment in which patients can be treated. Use of disinfectants in is an integral part of infection control. The rate of killing of microorganisms depends upon the type, concentration and time of exposure of the killing agent (disinfectant). Chlorinated compounds are frequently used in healthcare settings but chlorine dioxide has only been used in industries on a large scale. Aseptrol® is newly developed slow release chlorine dioxide and noncorrosive formula which can be used on a smaller scale basis. This study assessed the antimicrobial properties of Aseptrol® (48ppm and 24ppm) in comparison with previously used sodium dichloroisocyanurate containing formula, Presept® (10 000ppm). Both disinfectants killed more susceptible bacteria, such as Staphylococcus aureus, Pseudomonas. aeruginosa and Streptococcus mutans within 30 seconds and proved to be fungicidal by killing Candida albicans within 30 seconds. Aseptrol® and Presept® killed less susceptible mycobacteria such as Mycobacterium tuberculosis, Mycobacterium avium subsp. avium and blood borne organism Hepatitis B virus within 30 seconds. Highly resistant B. subtilis spores were killed in 2 and 2.5 minutes by Aseptrol® and Presept® respectively. Although manufacturers recommend that the disinfectant solutions should be prepared daily, when the shelf-life of prepared solutions stored in screw cap bottles was studied, the results showed that Aseptrol® can be effectively used for 27 day and Presept® for more than 37 days. Chlorinated disinfectants, such as Aseptrol® and Presept®, have potential to be used as intermediate to high level disinfectants in medical and dental settings, where above test organisms are primary contaminants. It is also possible to use them as sterilants, where semicritical conditions are required. Aseptrol® has an additional advantage because it is noncorrosive and can be used on metal instruments.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

In the fall of 2001, letters laced with anthrax spores were delivered to various news organizations in New York and Florida, as well as to two Senators in Washington, D.C. Over 22 anthrax infections and five deaths resulted from exposure to these spores, and decontamination of the affected buildings was both time consuming and costly. Since these attacks, interest in sporicidal disinfectants has increased greatly. Many chemical sporicidal disinfectants are available commercially, but the exposure time required to sterilize can be relatively long. In addition, some spores are simply injured or inhibited by chemical disinfectants, but not necessarily killed. Studies have shown that heat shocking spores after exposure to some disinfectants can aid in the recovery of injured spores, but these studies have not evaluated this effect on spores exposed to peracetic acid-based disinfectants. Recently, our lab has evaluated two novel peracetic acid-based chemical disinfectants, PeraDox™ and PeraDox Ultra™ for their activity against a variety of bacterial agents. Results indicated that the PeraDox™ solutions had extremely rapid cidal activity on a wide variety of microorganisms, especially those with innate germicide resistance, such as bacterial endospores. However, possible recovery of these spores after heat shock was not evaluated. The purpose of this study was to compare the sporicidal activity of three disinfectants: CIDEX™, PeraDox™, and PeraDox Ultra™ on three species of spores (Bacillus subtilis, Bacillus anthracis, and Clostridium sporogenes) in suspension, with and without heat shocking. Spores in suspension were exposed to disinfectants for specified times and assayed for viable spores. These spore suspensions were then heat shocked (80 ºC for 20 min) and assayed again. After exposure to peracetic acid-based disinfectants and subsequent heat shock, some B. subtilis spores recovered, resulting in up to a one log difference in viable spores. Other species and disinfectants did not show this effect. In addition, the activity of these disinfectants on spores dried onto a surface was evaluated using the standard AOAC sporicidal test. The current AOAC test specifies heat shocking after three weeks of incubation. In this study, we evaluated the AOAC sporicidal test by heat shocking immediately following disinfection and after three weeks of incubation as prescribed. Carrier tests showed a greater number of positive B. subtilis carriers when heat shocked immediately following PeraDox™, and PeraDox Ultra™ treatment, than when carriers were heat shocked after three weeks. In summary, results showed that heat shocking increases resuscitation of spores treated with some disinfectants, but not others. Spores in suspension and those dried onto carriers responded similarly to heat shocking. Finally, PeraDox™ formulations had surprisingly rapid sporicidal kinetics.

Disinfectants are added to the water distribution system and swimming pools to control the growth of pathogenic microorganisms in water. High disinfectant levels are health hazards since they produce disinfectant by-products which are carcinogens. Thus, monitoring the amount ofresidual disinfectants present and maintaining an optimal amount of residual disinfectants throughout the distribution network is very crucial for safe water distribution. Colorimetric measurements are the current standard for measuring disinfectant levels in water. However, it is very difficult to integrate colorimetric measurements into automated monitoring devices. Redox active molecules like the phenyl-capped aniline tetramer (PCAT) can be incorporated as a dopant into a single wall carbon nanotube sensor for detecting oxidant in drinking water. The sensor works on the principle of oxidizing adsorbed redox molecules on carbon nanotubes by oxidant present in drinking water thus changing the resistivity of the carbon nanotube film. Most commonly used disinfectants are HOCl, Cl2, ClO2, Chloramine, KMnO4, HOBr, H2O2, O3, Br2, I2, etc. They all are oxidizing agents and can be distinguished from one another as they have different oxidation potentials. For water treatment purposes, it is not enough to know the disinfectant level, but it is also very important to identify which disinfectant is present. Currently, there is no standard method for distinguishing different disinfectants presents in water. The development of sensor arrays based on redox active molecules having different redox potentials is a potential pathway towards differentiating between different disinfectants in water. Different aniline oligomers were synthesized to create a library of redox active molecules. Redox properties of these molecules have been determined, and expected results were compared with the sensor performance. In the future, these sensors can be incorporated into a reliable, resettable and reagent free sensor array for monitoring and distinguishing different disinfectants in water. Being able to constantly monitor the disinfectant level and identifying the disinfectant present in water will enable us to design an improved and sustainable disinfecting system. / Thesis / Master of Science (MSc)

Gangrenous dermatitis (GD) has become a major health problem among broiler flocks in the United States, resulting in high mortality, carcass condemnations, and trimmed parts. There are large economic losses due to GD. Clostridium septicum, Clostridium perfringens type A, and Staphylococcus aureus are the etiologic agents associated with GD. Gangrenous dermatitis has been associated with birds that have a compromised immune system. It is known that the gastrointestinal (GI) tract plays a crucial role in animal health and performance. The development of a healthy normal microflora in the GI tract benefits the host by improved resistance to pathogens. Our hypothesis is the application of commercial disinfectants, probiotics, vitamins, acidifiers, and windrowing technologies will reduce Clostridium levels in poultry operations. The objective of the first study was to administer probiotics to commercial broilers on three farms periodically throughout the grow-out cycle to conclude if bird health and performance was improved. The objective of the second study was to use commercial disinfectants, vitamins, acidifiers, and windrowing technologies on three farms in multiple houses and determine their effects on broiler production parameters. During grow-out, standard production practices were followed in all experiments and standard production parameters were measured. On all three farms in this study, the probiotic-treated houses had no mortality due to GD and an increase (P </= 0.05) in body weight gain was observed unlike their respective control houses. These experiments indicate that the application of probiotic in this field trial significantly altered the onset of GD by providing the birds with normal GI flora that contributed to their overall health during a commercial field study. When evaluating the different products and field technologies to control GD, our laboratory observed that treatment houses that were windrowed and received added vitamins did break with GD. Houses that were treated with peroxymonosulfates and monoglyceride, peroxymonosulfates, or glutaraldehyde litter disinfectants; acidifiers or vitamins had higher gross and net pounds weight gain at processing than their respective control houses. In conclusion, the significance of this work was to determine if products and technologies can be used by growers in commercial broiler houses to eliminate disease.

Lietuvoje registruotų dezinfekcinių priemonių: baliklio, TH4+, Safe 4, Ecocid S, formalino, buvo atliktas tyrimas, nustatyti Microsporum canis jautrumą, dezinfektantui. Patogeninio mikromiceto M. canis kolonijos išskirtos iš dermatofitija sergančių kačių. / Experiment was done to determine Microsporum canis sensitivity for disinfectant, using detergents which are registered in Lithuania: bleach , TH4 + , Safe 4 , S ecocide , formalin. Micromycetes pathogenic M. canis colonies isolated from cats which infected by dermatophytosis.