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Atividade antibacteriana/desinfetante de extrações galênicas de Jacaranda micrantha Cham. (caroba) sobre cepas de salmonela e estafilococos padrões e de isoladas em produtos de origem animal.Drebes, Tainá January 2014 (has links)
Relatos sobre resistência de microrganismos a inúmeros produtos químicos-sintéticos convencionais, bem como demanda por tecnologias adequadas ao sistema de produção orgânico/agroecológico motivaram o desenvolvimento dessa pesquisa buscando soluções antimicrobianas originadas de extrações de vegetais. O objetivo deste trabalho foi avaliar atividade desinfetante em extrações de Jacaranda micrantha Cham. (caroba), selecionada baseado em investigação etnográfica sobre plantas medicinais nativas no sul do Brasil. Foram confrontadas as cepas padrões Salmonella Choleraesuis ATCC 10708 e Staphylococcus aureus ATCC 25923, bem como as isoladas em alimentos de origem animal Salmonella spp (N=20) e Staphylococcus coagulase positiva (N=20). O método foi o de diluição, pelo teste de suspensão quantitativo para avaliar atividade bactericida de desinfetantes e antissépticos químicos. As formas foram decocto e extrato hidroetanólico (EH). A triagem, com os organismos padrões, ocorreu nas proporções (p : v) 5 g : 100 mL, 10 g : 100 mL e 20 g : 100 mL, hidratados ao volume inicial. As densidades populacionais (DP) de confronto foram 107, 106 e 105 UFCmL-1, nos tempo de contato de oito e 24 horas. A proporção 10 g : 100 mL foi usada para confrontar as isoladas. Verificada a identidade fitoquímica detectou-se a presença de compostos fenólicos, taninos condensados e flavonas tanto no decocto quanto maceração hidroacoólica, e de saponinas apenas no decocto. A triagem evidenciou que o decocto praticamente não promoveu redução das densidades populacionais frente as duas padrões, o mesmo ocorrendo frente às isoladas. Já o EH, na menor proporção p : v, inativou as cepas padrões na menor DP, e nas proporções 10 e 20 : 100 todas DP (exceção de 107 da Salmonella, apenas com redução). Frente as isoladas de Salmonella spp., inativou 5 % delas nas DP 106 e 105 UFCmL-1, e frente as Staphylococcus coagulase positiva, 5 % na DP 107, 40 % na 106 e 75 % na 105 UFCmL-1. Concluiu-se que o decocto pouco apresentou atividade antibacteriana, enquanto que o EH promoveu ação de redução logarítmica das densidades populacionais ou mesmo de inativação total frente todas as bactérias. As evidências mostram que além da densidade populacional de confronto, características intrínsecas dos indivíduos isolados dos dois gêneros também interferiram no tempo necessário para que a ação fosse promovida. / Reports of resistance of microorganisms to many conventional chemical-synthetic products, as well as the demand for appropriate organic / agroecological system technologies motivated the development of this research originated seeking antimicrobial solutions for extractions vegetables. The objective of this study was to assess disinfectant activity extractions Jacaranda micrantha Cham. (caroba), selected based on ethnographic research on native medicinal plants in southern Brazil. Standards strains Salmonella Choleraesuis ATCC 10708 and Staphylococcus aureus ATCC 25923 were compared, as well as isolates in foods of animal origin: Salmonella spp (N = 20) and Staphylococcus coagulase positive (N = 20). The method was to dilution by the quantitative suspension test for evaluating bactericidal activity of chemical disinfectants and antiseptics. The forms were hydroethanolic extract (HE) and decoction, screening with standards strains, occurred in the proportions (p: v) 5 g: 100 mL, 10 g: 100 ml and 20 g: 100 ml, hydrated to the original volume. Population densities (PD) of confrontation were 107, 106 and 105 UFCmL-1, the contact time of 8 and 24 hours. The ratio 10 g: 100 mL was used to confront the isolates. Verified the identity phytochemical detected the presence of phenolic compounds, flavones and condensed tannins as hidroacolic both the decoction and saponins only decoction. The screening showed that the decoction hardly promoted reduction of population densities across the two standards, the same occurring against isolated. Have the HE, the lowest proportion p: v, inactivated strains patterns in lower PD, and in the proportions 10 and 20: 100 all PD (except for the 107 Salmonella, only reduction). Against isolates of Salmonella spp. 5% of inactivated at 106 and 105 UFCmL-1 PD and against Staphylococcus coagulase positive in 5% PD 107, 40% 106 and 75% at 105 UFCmL-1. It was concluded that the decoction showed little antibacterial activity, while the hydroalcoholic extract promoted action log reduction in population density or total inactivation forward all bacteria. Evidence shows that in addition to population density of confrontation, intrinsic characteristics of isolated individuals of both genders also interfered in the time required for the action to be promoted.
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Atividade antibacteriana e antifúngica, in vitro e in situ, do extrato etanólico de própolis verde, frente a micro-organismos presentes em bebedouros avícolasSouza, Francine Bretanha Ribeiro de 21 February 2014 (has links)
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Previous issue date: 2014-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O uso de produtos naturais com fins medicinais, para tratamento, cura e prevenção de doenças é uma das formas mais antigas de prática medicinal da humanidade. A própolis é uma substância resinosa natural, produzida por abelhas melíferas a partir de exsudatos coletados em diferentes partes das plantas, que vem sendo utilizada desde a antiguidade na medicina popular, tanto humana quanto veterinária, devido as suas propriedades terapêuticas. A atividade antimicrobiana é relatada em diversos estudos que utilizam como modelo experimental diferentes gêneros de vírus, bactérias, fungos e parasitas, porém são raros os estudos utilizando-a como desinfetante. Avaliou-se um extrato etanólico de própolis verde (EEPV), em comparação com um desinfetante comercial à base de amônia quaternária, quanto à capacidade desinfetante in situ em bebedouros utilizados para frangos de corte até 28 dias de idade das aves. O EEPV também foi avaliado, in vitro, contra as bactérias isoladas a partir de suabes dos bebedouros utilizados no experimento. Aos 28 dias de idade dos frangos, quando o desafio microbiano foi maior, a ação do EEPV como desinfetante foi semelhante à ação do desinfetante comercial a base de amônia quaternária. Nesta mesma idade das aves, o EEPV, assim como o desinfetante comercial, inibiu por completo o crescimento fúngico nos bebedouros. O EEPV apresentou ação in vitro contra as bactérias gram positivas Staphylococcus sp. coagulase negativa, S. aureus, Corynebacterium sp., isoladas a partir de suabe coletado dos bebedouros, além da bactéria gram negativa Escherichia coli. / The use of natural products for medicinal purposes for treatment, cure and prevention of diseases is one of the most antique forms of medical practice of humanity. Propolis is a natural resinous substance produced by honeybees from exudates collected of different parts of the plant and has been used as a therapeutic compound since antiquity in the popular medicine both human and veterinary due to its therapeutics properties. The antimicrobial activity is mentioned in various studies applying different genus of viruses, fungus, bacterias and parasites as a experimental model. An ethanolic extract from green propolis was evaluated as to the sanitizer capacity in situ over drinking fountains used for broilers in comparison with a commercial disinfectant based on quaternary ammonia. The extract was also evaluated in vitro against bacterias isolated from the drinking fountains used in the experiment. At 28 days of broiler age when the microbial challenge was greater the action of the extract as a disinfectant was similar to the action of the commercial disinfectant based on quaternary ammonium. In the same age of the birds both the propolis extract as well as the commercial disinfectant the fungal growth was completely inhibited in the drinking fountains. The extract presented action in vitro against gram positive bacteria Staphylococcus sp. negative coagulase, S. aureus, Corynebacterium sp. isolated from swabs collected from the drinking fountains and also the gram negative bacteria Escherichia coli.
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Zásobování pitnou vodou bez použití desinfekčního činidla / Water supply without a residual disinfectantRajnochová, Markéta January 2017 (has links)
The diploma thesis focuses on the water distribution system functioning without chlorine-based disinfectant. This thesis contains research of documented cases of examples of drinking water distribution systems both abroad and in the Czech Republic, which do not use disinfectants. Moreover, the thesis pay attention to chlorine and its effects on bacteria. The thesis deals with the first assessment of water supply structure, which determines whether the water supply structure is suitable for operating without disinfectant. The thesis describes the process of transition to the disinfectant-free operation and determines the undesired events, which may occur with the ending of the use of disinfectant. As a part of the research, the thesis examines the water supply system in village Kateřinice, to determine if it is suitable for operation without disinfectant.
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Drinking Water Microbial CommunitiesEl-Chakhtoura, Joline 11 1900 (has links)
Water crises are predicted to be amongst the risks of highest concern for
the next ten years, due to availability, accessibility, quality and management
issues. Knowledge of the microbial communities indigenous to drinking water is
essential for treatment and distribution process control, risk assessment and
infrastructure design. Drinking water distribution systems (DWDSs) ideally
should deliver to the consumer water of the same microbial quality as that
leaving a treatment plant (“biologically stable” according to WHO). At the start
of this Ph.D. program water microbiology comprised conventional culturedependent
methods, and no studies were available on microbial communities
from source to tap.
A method combining 16S rRNA gene pyrosequencing with flow
cytometry was developed to accurately detect, characterize, and enumerate the
microorganisms found in a water sample. Studies were conducted in seven fullscale
Dutch DWDSs which transport low-AOC water without disinfectant
residuals, produced from fresh water applying conventional treatment. Full-scale
studies were also conducted at the desalination plant and DWDS of KAUST,
Saudi Arabia where drinking water is produced from seawater applying RO
membrane treatment and then transported with chlorine residual. Furthermore,
biological stability was evaluated in a wastewater reuse application in the
Netherlands.
When low-AOC water was distributed without disinfectant residuals,
greater bacterial richness was detected in the networks, however, temporal and
spatial variations in the bacterial community were insignificant and a substantial
fraction of the microbiome was still shared between the treated and transported
water. This shared fraction was lower in the system transporting water with
chlorine residual, where the eukaryotic community changed with residence time.
The core microbiome was characterized and dominant members varied between
the two systems. Biofilm and deposit-associated communities were found to
drive tap water microbiology regardless of water source and treatment scheme.
Network flushing was found to be a simple method to assess water
microbiology. Biological stability was not associated with safety. The biological
stability concept needs to be revised and quantified. Further research is needed
to understand microbial functions and processes, how water communities affect
the human microbiome, and what the “drinking” water microbiome is like in
undeveloped countries. / The research presented in this doctoral dissertation was financially supported by and conducted in collaboration with Delft University of Technology (TU Delft) and Evides Waterbedrijf in the Netherlands.
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Evaluation and improvement of coagulant disinfectant products for humanitarian emergency reliefBorrett, Leigh A. 02 September 2020 (has links)
As climate change progresses, the number of extreme weather events are predicted to rise and generate an increase in climate related humanitarian emergencies. These emergencies result in complex displacements of populations, unsanitary conditions, and a corresponding increase in diarrheal disease risks within affected communities. Because diarrheal disease ranks as one of the major contributors to overall morbidity and mortality rates following a disaster, it is critically important that aid agencies are prepared to make informed decisions regarding the prevention of disease transmission. As water is one of the main transmission routes of diarrheal disease, providing clean and safe drinking water is acknowledged as one of the most important and effective interventions. Once we acknowledge the importance of this resource, we also acknowledge the need for quick, simple, and effective water treatment solutions.
The term point-of-use (POU) water treatment defines water treatment systems and technologies that are used at the point of consumption. These systems often treat relatively small batches of water and are operated by the consumer or head of household. POU water treatment systems and safe storage techniques have been shown to improve water quality and decrease diarrheal disease incidence and are therefore an effective option in humanitarian emergencies. One type of POU water treatment product - coagulant/disinfection products (CDPs) which are also known as flocculant/disinfectants, have been increasingly used in response to humanitarian emergencies. CDPs are shown to provide microbial and aesthetic (i.e. turbidity reductions) water quality improvements and post-treatment protective free chlorine residuals (FCRs). The relative simplicity of CDPs allows quick intervention for communities with few resources plus CDPs are durable, small, and ready for quick deployment. However, limited research has been completed on the different CDPs on the market or on methods to improve them.
This thesis explores CDPs and their role in emergency response through two interlinked perspectives:
1. First, in an overall review compiled as Manuscript #1 (Chapter 2), I assess the existing and current CDPs, how they perform in comparison to global water treatment guidelines, and where their limitations lie. The outcomes of this study provide a simple analysis for aid agencies to carefully select the CDPs used in emergency interventions; and
2. I take the findings from the research completed in Chapter 2 to develop a computational modelling approach to improving the residual protective capacity of the CDPs. These results are presented in Manuscript #2 (Chapter 3) . The outcomes are intended to serve two purposes: (1) to provide a baseline computational model to guide and encourage improvement and testing of these products by manufacturers; and (2) to provide an educational tool to facilitate understanding of these products and the key functions taking place during their treatment.
This thesis addressed the research objective of invoking conversation surrounding effective emergency response through developing solutions to provide clean drinking water in at-risk communities during complex humanitarian emergencies. / Graduate
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Fate of Nanomaterials in the Environment: Effects of Particle Size,Capping agent and Surface Cleaning Products on the Stability of Silver Nanomaterials In Colloidal Consumer Products.Radwan, Islam Mohamed Othman 01 October 2019 (has links)
No description available.
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Efficacy of Liming Forest Soil in the Context of African Swine Fever VirusTanneberger, Franziska, Abd El Wahed, Ahmed, Fischer, Melina, Deutschmann, Paul, Roszyk, Hanna, Carrau, Tessa, Blome, Sandra, Truyen, Uwe 13 June 2023 (has links)
Since September 2020, Germany has experienced the first ever outbreak of African swine
fever (ASF). The first known cases occurred exclusively in wild boar in forest areas in Brandenburg
and Saxony; in July 2021, infected domestic pigs were also confirmed for the first time. As wild boar
are considered the main reservoir for the virus in the European region, an effective interruption of this
infection chain is essential. In particular, the removal and safe disposal of infected carcasses and the
direct disinfection of contaminated, unpaved ground are priorities in this regard. For the disinfection,
highly potent as well as environmentally compatible disinfectants must be used, which are neither
influenced in their effectiveness by the soil condition nor by increased organic contamination. Thus,
in this study, slaked lime, milk of lime and quicklime (1% to 10% solutions) were selected for efficacy
testing against the test virus recommended by the German Veterinary Society (DVG), Modified
Vaccinia Ankara virus (MVAV), and ASF virus (ASFV) in conjunction with six different forest soils
from Saxony in two different soil layers (top soil and mineral soil) each. In summary, 10% of any
tested lime type is able to inactivate both MVAV and ASFV under conditions of high organic load
and independent of the water content of the soil. At least a 4 log reduction of the virus titer in all
tested forest soil types and layers and by all applied lime types was observed. In conclusion, the high
efficacy and suitability of all tested lime products against both viruses and in the presence of high
organic load in forest soil can be confirmed and will help to control ASF spread.
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Genotoxicity of haloacetic acids, aspirin and ibuprofen in human cells. Genotoxic effects of water disinfectant- by-products in human blood and sperm and bulk and nano forms of aspirin and ibuprofen in human blood of respiratory disease patientsAli, Aftab H.M. January 2014 (has links)
This project focuses on two important topics which may pose hazards to human health. Firstly, drinking water disinfection by-products (DBPs), which are generated by the chemical disinfection of water have been investigated. What has not been shown is the effect of DBPs in human germ cells as well as somatic cells and whether oxidative stress is involved in the mechanism of genotoxic action. Three different DBPs (halo acetic acids: HAAs), together with the antioxidants – catalase and butylated hydroxyanisole (BHA), were investigated in peripheral blood cells and sperm from healthy individuals using the Comet assay and lymphocytes only using the micronucleus assay. Secondly, nanoparticles of the non-steroidal anti-inflammatory drugs (NSAIDs), aspirin and ibuprofen, have been investigated in patients with respiratory diseases, in the micronucleus assay and the Comet repair assay. NSAIDs inhibit cyclooxygenase enzyme activity, which plays part in tumour progression. In the Comet assay, BHA and catalase were able to reduce DNA damage in both cell types compared to HAAs alone. Similarly, in the micronucleus assay, micronuclei were reduced with the antioxidants, suggesting oxygen radical involvement in both assays. With the NSAIDs, reductions were seen for DNA damage in the micronucleus assay with aspirin and ibuprofen nanoparticles compared to their bulk forms. Using the Comet repair assay, aspirin and ibuprofen nanoparticles aided repair of DNA to a greater extent than their bulk counterparts, which in turn showed better repair compared to samples repaired without NSAIDs. These observations show the importance of DBPs and NSAIDs in genotoxic public health issues. / United Kingdom India Education and Research Initiative (UKIERI).
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Cross-Contamination Risk of Dental Tray Adhesives: An In Vitro StudyPaczkowski, Isabel, Stingu, Catalina S., Hahnel, Sebastian, Rauch, Angelika, Schierz, Oliver 05 May 2023 (has links)
Background: The aim of this study was to investigate the risk of cross-contamination in dental tray adhesives with reusable brush systems. Methods: Four dental tray adhesives with different disinfectant components were examined for risk as a potential transmission medium for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus oralis, and Candida albicans. Bacterial and fungal strains were mixed with artificial saliva. The contaminated saliva was intentionally added to tray adhesive liquid samples. At baseline and up to 60 min, 100 microliters of each sample were collected and cultivated aerobically on Columbia and Sabouraud agar for 24 or 48 h, respectively. Results: At baseline, contamination with Staphylococcus aureus and Candida albicans could be identified in three out of four adhesives. In the subsequent samples, low counts of up to 20 colony-forming units per milliliter could be observed for Staphylococcus aureus. All other strains did not form colonies at baseline or subsequently. Adhesives with isopropanol or ethyl acetate as disinfectant additives were most effective in preventing contamination, while adhesives with hydrogen chloride or acetone as a disinfectant additive were the least effective. Conclusion: Within 15 min, the tested adhesives appeared to be sufficiently bactericidal and fungicidal against all microorganisms tested.
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<b>Investigating application methods and active agents for healthcare-related surface contamination</b>Geraldine Madalitso Tembo (9754958) 19 July 2024 (has links)
<p dir="ltr">Healthcare-acquired infections (HAIs) cause a burden in acute care hospitals in the United States. HAIs are caused by <i>Staphylococcus aureus</i>, along with other pathogens found on high-touch and non-high-touch surfaces in hospital environments (e.g., bed rails, blood pressure cuffs, countertops, and floors). To minimize the growth and cross-contamination of pathogens, it is vital to use disinfectants for surface decontamination. In this work, the impact of different application methods and disinfectant active agents was evaluated for use on different healthcare-related surfaces. The first study examined the cross-contamination potential of an auto-scrubber when used to clean and disinfect a 2m<sup>2</sup> vinyl floor contaminated with <i>S. aureus</i>. Five EPA-registered disinfectants and a cleaner were used with three application methods. Hydrogen peroxide and quaternary ammonium compounds-based disinfectants significantly resulted in less cross-contamination compared to the cleaner. However, there were no significant differences among the application methods used. In the second study, manual floor cleaning and disinfecting on a two-square-meter vinyl floor with three different moping materials were evaluated to assess their ability to prevent cross-contamination. Evidence showed that there were significant differences among the products used, with Hydrogen peroxide and quaternary ammonium compound products being the most effective. The cleaner caused the most cross-contamination, while cotton mops resulted in significant cross-contamination among materials used. Study three investigated the differences among four application methods used with three different wiping cloths (Cotton, microfiber, and nonwoven) on a 2m<sup>2</sup> Formica board. A spray surface and wipe method was successful in decreasing <i>S. aureus</i> on the surface. A hydrogen peroxide-based product was most effective in reducing bacteria at contamination areas and minimizing cross-contamination. Microfiber cloth picked up significantly more bacteria at contaminated areas. Post disinfection, there was evidence of cross-contamination at sampling areas regardless of product type, wiping cloth, and application methods used, with the cotton cloth causing the most cross-contamination. Viable bacteria were found on the wiping cloths used and on worker's gloves. Together, this work shows that the use of disinfectants is important in hospital environments. The choice of product, wiping material, and application method are principal in the disinfection process as they influence disinfection failure or success.</p>
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