Dissertations / Theses: 'Anti-infective agents'

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Osborne, Sadie D. "Synthesis of carbohydrate based anti-infective agents." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394179.

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Allcock, Robert William. "The synthesis and evaluation of some anti-infective agents." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341277.

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Kanwar, Ankush. "Studies Aimed at the Synthesis of Anti-Infective Agents." Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7176.

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Infectious diseases continue to be a major concern worldwide. They are the second leading cause of death after heart disease. Factors such as an increasing global population, travel, urbanization, global climate change and evolution of pathogens have made infectious diseases more common. Infectious diseases, particularly neglected tropical diseases (NTDs) result in many deaths worldwide. Malaria and leishmaniasis are two common (NTDs) which affect low income countries around the globe. Low cost drugs with novel mechanism of action are required to tackle the growing resistances of parasites against current drugs used in the developing world, where most of the cases occur. The first part of this manuscript (chapters 1 - 3) describes the synthesis of novel analogs active against Leishmania donovani parasite which causes leishmaniasis. Leishmaniasis is a vector-borne complex group of diseases transmitted through the bite of an infected female sand-fly. Its clinical manifestations range from the less severe (cutaneous) to fatal (visceral) forms depending upon infecting species, immunity of host and the environment. Reports have suggested the role of Heat shock protein 90 (Hsp 90) in the differentiation of the Leishmania parasite from the promastigote stage to the pathogenic amastigote stage inside the host. A series of tetrahydro-indazole, tetrahydro-pyrazolo pyridine and radicicol hybrid compounds were prepared based on known Hsp 90 inhibitors, SNX2112 and NVP-AUY922. The synthetic approach allowed us to generate a diverse library of analogs which were used to probe the hydrophobic pocket of Hsp 90 active site. The most active compound, was found to be twice more active as the clinically used drug, Miltefosine, in an infected macrophage assay with an IC50 = 0.88 µM. The second part of this manuscript (chapters 4 - 5) describes the synthesis of xanthurenic acid analogs as antimalarial drugs. Xanthurenic acid (XA) is a vital component for the gametogenesis of the Plasmodium inside the mosquito’s gut. Gametogenesis plays an important part in the continuation of the parasite’s life cycle. A series of xanthurenic acid analogs were synthesized with the aim of inducing premature exflagellation of the microgametes, thus blocking the key step required for the transmission of parasites from humans to the mosquito. A biotinylated xanthurenic acid analog and a clickable xanthurenic acid analog were also synthesized which will help us investigate the mechanism of action of xanthurenic acid in inducing gametogenesis in mosquito. In the preliminary screening efforts in an exflagellation assay, analog 4.40 showed promising activity and was more active in inducing exflagellation than xanthurenic acid. An exflagellation assay of other analogs is currently being pursued. Further investigations into the molecular target and mechanism of action are underway with the biotinylated xanthurenic acid analog.

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Alamu, Josiah Olusegun Herwaldt Loreen A. "Evaluation of antimicrobial use in a pediatric intensive care unit." Iowa City : University of Iowa, 2009. http://ir.uiowa.edu/etd/277.

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Pütsep, Katrin. "On the control of the microflora in the gastro intestinal tract : functional examples of antibacterial peptides from Helicobacter pylori and mouse small intestine /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4267-6/.

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Giraldi, Cátia. "Enterococcus isolados de alimentos: caracterização molecular e perfil de resistência a antimicrobianos." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1136.

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Os enterococos são patógenos com considerável capacidade de expressar resistência a vários antimicrobianos e com abundante representatividade em alimentos. Este estudo teve por finalidade realizar o isolamento de cepas do gênero Enterococcus em alimentos, representados por carne de frango e carne suína (crua e processada), analisar o perfil de resistência antimicrobiana através do método de disco-difusão e identificar através de técnicas moleculares as espécies dos isolados e os genes codificadores de resistência para vancomicina e tetraciclina. Foram analisadas 36 amostras, totalizando 54 cepas isoladas pertencentes ao gênero Enterococcus. A espécie detectada em maior ocorrência nos isolados de carne crua de frango (40%) e carne crua suína (29%) foi E. faecalis e nos isolados de produtos cárneos processados (100%) E. faecium. E. casseliflavus/E. flavencens teve seu isolamento apenas em produto processado. A espécie E. gallinarum não foi confirmada entre as amostras de alimentos analisadas. As espécies E. faecalis e E. faecium isoladas a partir de carne crua de frango foram significativamente mais resistentes que as isoladas das demais amostras, apresentando altos percentuais de resistência para: estreptomicina, ciprofloxacina, norfloxacina, eritromicina, vancomicina e tetraciclina. Isolados de carne crua de frango e suína apresentaram gene de resistência para tetraciclina e vancomicina. Portanto, sugere-se que, alimentos de origem animal possam desempenhar um papel importante na disseminação e transferência de enterococos resistentes e/ou genes de resistência aos seres humanos.
Enterococci are pathogens with considerable ability to express resistance to multiple antimicrobials and abundant representation in foods. This study aimed to carry out the isolation of strains of the genus Enterococcus in food, represented by chicken and pork (raw and processed), to analyze the profile of antimicrobial resistance by the disk diffusion method and by molecular techniques to identify species isolates and genes encoding resistance to vancomycin and tetracycline. 36 samples, totaling 54 strains belonging to the genus Enterococcus were analyzed. The species detected in most occurred in isolates from raw chicken meat (40 %) and raw pork (29%) was isolated in E. faecalis and processed meat products (100%) E. faecium. E. casseliflavus / E. flavencens had its isolation only in the processed product. The species E. gallinarum was confirmed between food samples surveyed. E. faecalis and E. faecium isolates from raw chicken meat isolated were significantly more resistant than the other samples, showing high percentage of resistance to: streptomycin, ciprofloxacin, norfloxacin, erythromycin, vancomycin and tetracycline. The isolated raw poultry and swine gene showed resistance to tetracycline and vancomycin. Therefore, it is suggested that food of animal origin may play an important role in the dissemination and transfer resistant enterococci and / or resistance genes to humans.

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Kasanah, Noer. "Marine anti-infective agents : bioactivity, microbial production, biotransformation and biosynthetic study /." Full text available from ProQuest UM Digital Dissertations, 2008. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1850412761&SrchMode=1&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1279226241&clientId=22256.

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Sherrill, Jennifer Lynne. "Surface modification of nylon 6,6 to form Light-Activated Antimicrobial Materials (LAAMS)." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/18964.

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Everett, Lucy Margaret. "The effects of antibiotic stress on the expression of virulence factors by strains of Staphylococcus aureus diplaying vancomycin-intermediate resistance." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272854.

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Toft, Simonsen Henrik. "Ethnopharmacological and phytochemical investigation of Melicope species from Réunion Island /." Cph. : Department of Medicinal Chemistry, Royal Danish School of Pharmacy, 2002. http://www.dfh.dk/phd/defences/Henrik%20Toft%20Simonsen.html.

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Tong, Carmen. "Screening for inhibitors of Staphylococcal Sortase A as novel anti-infective agents." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/53236/.

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Staphylococcus aureus is a Gram-positive human pathogen that has developed resistance to all traditionally used antibiotics. Sortase A (SrtA) is a 'house-keeping' enzyme present in a number of Gram-positive organisms including S. aureus that is responsible for the covalent anchoring of proteins to the cell wall through the recognition of a highly conserved LPXTG motif. Many of the proteins it anchors are involved in virulence and immune evasion suggesting that it is an attractive target for potential anti-infective therapies. Moreover, as SrtA is not vital for bacterial growth or survival, inhibition may not select for the development of drug-resistance, unlike conventional antibiotics. This study evaluated different assays to assay SrtA activity and includes an in vitro Fluorescence Resonance Energy Transfer (FRET) assay using purified recombinant SrtA protein and an in vivo whole cell-based assay that measured SrtA-mediated anchoring of Gaussia luciferase (GLuc) in S. aureus. A further in vivo assay was evaluated, which measured SrtA activity using fluorescence as a reporter and analysis by flow cytometry and structured illumination microscopy. In this study three novel small molecules were identified as potential inhibitors of SrtA using in silico computational docking and SAR analysis; NCC-00014270, NCC-00076932 and NCC-00032784. These compounds were shown to inhibit SrtA in vitro in a dose-dependent manner with IC50s of 140 ± 24.6 µM, 172 ± 28.1 µM and 628 ± 122 µM respectively and were shown to act as competitive inhibitors of the SrtA. With the use of an in vivo reporter, it was shown that all three compounds negatively affected SrtA-mediated anchoring in S. aureus whole cells. Moreover, the cytotoxicity of these lead compounds against eukaryotic cells was assessed. Overall, these data suggest that two of the three lead compounds were potential 'hit' molecules for further structural modification for increased inhibitory activity against SrtA.

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Khara, Jasmeet. "De novo design of antimicrobial peptides for application as anti-infective agents." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/45283.

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The escalating threat of antimicrobial resistance has increased pressure to develop novel therapeutic strategies to tackle drug-resistant infections. Antimicrobial peptides (AMPs) have gathered considerable interest as a new source of antibiotics due to their broad-spectrum and rapid bactericidal activities, in addition to their ability to synergise with conventional antibiotics against drug-resistant pathogens. However, natural AMPs are increasingly recognised as poor therapeutic candidates due to their long sequences, which inadvertently induce significant systemic toxicities and translate into higher manufacturing costs. To enhance their clinical utility, short synthetic analogues have been designed by fine-tuning their selectivity to preferentially interact with microbial over mammalian cells. However, the strategies employed by the majority of these studies have remained largely empirical, often utilising natural AMPs as templates, or helical wheel projections to perform modifications by replacing, deleting or scrambling amino acid sequences. Furthermore, synthetic peptides derived from natural host defence peptides possess high sequence similarity, which may promote cross-resistance when applied as therapeutic agents. Adopting a de novo approach enables the rational design of short synthetic AMPs, whilst mitigating concerns of resistance development to naturally occurring innate immune peptides. However, such rational approaches have yet to be applied to the de novo design of short synthetic anti-mycobacterial peptides. As such, this thesis first explores the feasibility of rationally designed synthetic alpha-helical AMPs as anti-tubercular agents and subsequently, a new sequence-based approach for the design of multifunctional alpha-helical peptides with idealised facial amphiphilicity, is proposed. In doing so, we demonstrate that the adoption of such systematic design principles, in the optimisation of short synthetic AMPs, could facilitate the development of safe and effective novel peptide therapeutics for application in infectious and inflammatory human diseases.

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Svinhufvud, Lillemor Borthen. "Selective modulation of the oropharyngeal microflora with topical administration of antimicrobial agents." Stockholm : Kongl Carolinska Medico Chirurgiska Institutet, 1987. http://catalog.hathitrust.org/api/volumes/oclc/16150025.html.

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Mustafa, Manal. "Studies on uptake and effect of triclosan on production of inflammatory mediators in human gingival fibroblasts /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-714-2.

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Khadambi, Tshiwela Norah. "Antimicrobial properties of phenolic compounds from sorghum." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-03022007-164705.

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Mativandlela, Sannah Patience Nkam. "Evaluation of isolates and identified phenolics from pelargonium sidiodes against tuberculosis, other bacteria and fungi." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02132006-113925.

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Ali, Saleh A. "Antimicrobial and antioxidant activity of two desert truffles, Tirmania and Terfezia." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99316.

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Two species of desert truffles, Tirmania and Terfezia were collected from the Northern desert region in Saudi Arabia for antimicrobial and antioxidant activity testing. Both species were extracted with four types of extraction solutions, methanol, ethanol, ethyl acetate and water to test for antimicrobial activity and with three extraction solutions, methanol, ethanol and water for antioxidant activity. Using disc diffusion method, the extracts were subjected to twenty three different microorganisms to observe the antimicrobial activity by measuring clear zones. Methanol extract from Tirmania was the most effective, followed by those extracted with ethanol, water and ethyl acetate respectively. In Terfezia, ethanol extract was better than methanol extract in effectiveness. Ethyl acetate extracts were the least effective. The results indicate that truffles possess antimicrobial activity with broad spectrum effects against Gram positive, Gram negative, aerobic and anaerobic bacteria as well as Saccharomyces, while no effect was recorded with fungi. The results on antioxidant activity showed that truffles have very strong antioxidant property with 99.9% with ethanol extracts of Tirmania species and 95.5% with ethanol extract of Terfezia species using beta-carotene bleaching method and antioxidant property with 96.1% with ethanol extracts of Tirmania species and 95.3% with methanol extract of Terfezia species using DPPH free radical method.

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Palenske, Nicole Marie Dzialowski Edward. "Effects of triclosan, triclocarban, and caffeine exposure on the development of amphibian larvae." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/permalink/meta-dc-11016.

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Van, Eeden Nestor. "Synthesis of some potential antimicrobial carbocyclic compounds." Thesis, Cape Technikon, 1994. http://hdl.handle.net/20.500.11838/745.

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Thesis (M. Diploma in Technology (Chemistry))--Cape Technikon, 1994
Some naturally occurring compounds containing the naphtho [2,3 - c] pyran ring system have been found to be useful antibiotic agents and thus the laboratory synthesis ofthese compounds and their derivatives are of importance in the medical field. Their antibiotic and even antineoplastic activities are attributed to their potential to act as alkylating agents, via a bioreductive process. This thesis deals with studies directed towards the synthesis of some benzo [c] pyrans as these compounds also possess the correct structural configuration to undergo the bioreductive process, and act as alkylating agents to cellular nucleic acids. Chapter Two describes the synthesis 00,4 dihydro - 1,3 - dimethyl- IH - benzo - [cl pyran - 5,8 - quinone (13) by employing a base induced cyclization with potassium tertiary butoxide. This compound was proven to be biologically active against both Gram positive and Gram negative organisms. (±) (1R, 3R, 4R) - 3,4 - Dihydro - 4 - hyroxy -1,3 - dimethyl- 1H - benzo [e] pyran - 5,8quinone (17) and its 4 S diastereomer (18) were synthesized with cerium (IV) ammonium nitrate as the cyclizing reagent. Antimicrobial evaluation ofcompound (17) displayed inhibitory activity against both Gram positive and Gram negative organism growth. This is discussed in Chapter Three. In Chapter Four, the synthesis ofthe benzo analogue ofthe naturally occurring naphthopyran antibiotic, hongconin, is discussed. The synthetic route used for this synthesis could well be applied to synthesise hongconin.

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Amaral, Lílian Ferreira Barbosa 1978. "Avaliação da segurança e eficácia do extrato de Caryocar brasiliense obtido por CO2 supercrítico e sua aplicação como ativo para formulações antissépticas." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312995.

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Orientador: Priscila Gava Mazzola
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-26T03:28:14Z (GMT). No. of bitstreams: 1 Amaral_LilianFerreiraBarbosa_D.pdf: 2465793 bytes, checksum: e61ffae5669fa378935586624f7137b2 (MD5) Previous issue date: 2014
Resumo: As indústrias cosméticas e farmacêuticas têm um crescente interesse na substituição dos antimicrobianos sintéticos nos produtos dermatológicos, devido à resistência dos microrganismos aos antimicrobianos convencionais. O pequi (Caryocar brasiliense Camb) é uma frutífera nativa do Cerrado brasileiro utilizada na medicina popular, na indústria cosmética e na alimentação, com atividades leishmanicida e antimicrobiana descritas na literatura. O objetivo principal deste trabalho foi avaliar a segurança e a eficácia do extrato de Caryocar brasilense obtido por CO2 supercrítico visando sua aplicação cosmética. A concentração inibitória mínima (CIM) frente às bactérias Escherichia coli, Pseudomonas aeruginosa e Staphylococcus aureus foi determinada pelo método clássico de microdiluição em placas. O potencial antioxidante do extrato foi determinado por um método baseado na oxidação do 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). Para avaliação da citotoxicidade e fototoxicidade in vitro, foram utilizados métodos colorimétricos baseados na conversão do corante tetrazólio (XTT) e o método do vermelho neutro (3T3 NRU), respectivamente. Na avaliação do potencial de irritação ocular empregou-se o teste na membrana corioalantóide do ovo de galinha (HET-CAM). O Perfil fitoquímico do extrato foi analisado quanto à presença de alcalóides, saponinas, antraquinonas, esteróides, taninos, flavonóides e compostos fenólicos, de acordo com métodos colorimétricos padronizados. Os resultados obtidos indicam que o extrato de Caryocar brasilense obtido por CO2 supercrítico demonstra atividade antimicrobiana frente às bactérias testadas, além de potencial antioxidante comparado ao padrão testado. Adicionalmente, o extrato de Caryocar brasilense obtido por CO2 supercrítico não apresenta efeitos tóxicos, mostrando-se um extrato seguro. Estes resultados fornecem perspectivas de desenvolvimento de produtos para o cuidado pessoal, principalmente aqueles com atividade antisséptica e os que minimizam os danos causados pelos radicais livres
Abstract: The cosmetic and pharmaceutical industries have an increasing interest in replacing synthetic antimicrobials in dermatological products due to increased microbial resistance to conventional antimicrobial agents. Caryocar brasiliense Camb (pequi) is a typical Brazilian Cerrado fruit tree. Its fruit is used as a vitamin source for culinary purposes and as a source of oil for the manufacture of cosmetics. Leishmanicidal and antimicrobial activities have been reported previously. This study was designed to evaluate the safety and efficacy of C. brasiliense extract obtained by supercritical CO2 extraction. The minimum inhibitory concentrations (MICs) against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were determined by the classical microdilution method. Antiseptic activity against these organisms was evaluated by the plate diffusion method. The antioxidant potential of the extract was evaluated using a method based on the oxidation of 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). In vitro cytotoxicity and phototoxicity of C. brasiliense supercritical CO2 extracts were assessed using a tetrazolium-based colorimetric assay (XTT) and Neutral Red methods; eye irritation potential was assessed using the Hen's Egg Test ¿ Chorioallantoic Membrane (HET-CAM) Test Method. The extract¿s chemical profile was analyzed for the presence of alkaloids, saponins, anthraquinones, steroids, tannins, flavonoids, and phenolic compounds according to standard colorimetric methods. The C. brasiliense supercritical CO2 extract exhibits antimicrobial activity against all bacteria tested. It also possesses antioxidant activity, when compared to a vitamin E standard. We also found that the C. brasiliense (pequi) extract obtained by supercritical CO2 extraction did not present cytotoxic and phototoxic hazards This finding suggests that C. brasiliense supercritical may be useful for the development of cosmetic and/or pharmaceutical products, primarily for antiseptic skin products that inactivate, reduce, prevent, or arrest the growth of microorganisms with the inherent intent to mitigate or prevent disease as well as products that minimize damage caused by free radicals
Doutorado
Ciencias Biomedicas
Doutora em Ciências Médicas

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Samosorn, Siritron. "Development of berberine-based derivatives as novel antimicrobial agents." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20050819.161843/index.html.

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Hevener, Kirk Edward. "Structure- and ligand-based design of novel antimicrobial agents." View the abstract Download the full-text PDF version, 2008. http://etd.utmem.edu/ABSTRACTS/2008-052-Hevener-index.htm.

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Thesis (Ph.D.)--University of Tennessee Health Science Center, 2008.
Title from title page screen (viewed on February 2, 2009). Research advisor: Richard E. Lee, Ph.D. Document formatted into pages (xviii, 238 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 167-186).

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Wilson, Jason B. "Synthesis and evaluation of tetramic acids as antimicrobial agents." View the abstract Download the full-text PDF version, 2008. http://etd.utmem.edu/ABSTRACTS/2008-055-Wilson-Index.htm.

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Thesis (M.S.)--University of Tennessee Health Science Center, 2008.
Title from title page screen (viewed on February 27, 2009). Research advisor: Richard E. Lee, Ph.D. Document formatted into pages (viii, 40 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 36-40).

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Dorrington, Tarquin. "Recombinant antimicrobials for feed based delivery in aquaculture /." View online ; access limited to URI, 2005. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3188058.

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張麗 and Li Zhang. "Interactions of Bismuth complexes with biomolecules: insight into the mechanism of action of Bismuthantimicrobial agents." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B3124631X.

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Tohidi, Fatemeh. "Environmental occurrence of triclosan in wastewater and transformation fate and development of a method of derivatization of PFOS." HKBU Institutional Repository, 2016. http://repository.hkbu.edu.hk/etd_oa/285.

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Triclosan (TCS) as an antimicrobial agent in a variety of consumer products has drawn environmental and health care scientist's attention for over 40 years as it has been widely detected in environment. Once released to the environment, TCS can easily transfer to water bodies and soil due to its fair solubility and hydrophobicity. TCS is not considered as a toxic compound. However, two main reasons have bolded TCS occurrence important in the environment. Firstly, TCS can easily adsorb to and accumulate in the media possessing organic matter such as sludge, soli or tissue. Secondly, TCS can degrade/transform to other compounds with higher potential toxicity and persistency. While many degradation products have been observed in certain circumstances, the main easily-formed products can be pointed as 2,4-dichlorophenol (2,4-DCP), 2,8-dichlorodibenzoparadioxin (2,8-DCDD) and methyl triclosan (MTCS). 2,4-DCP is listed as the priority toxic pollutant by US Environmental Protection Agency. 2,8-DCDD is a member of dioxin family with a recently reported relative potency factor of 1₉104. This compound is suspected to transform to higher chlorinated dioxins when exposed to light or chlorine. MTCS, resulted from microbial methylation of TCS, has received much attention recently due to its persistency. Although TCS has been studied vastly, its̀ fate and behavior in wastewater and sludge as the first receiver in the environment has not been investigated deeply so far. In this research, attempt was done to answer some so far unanswered questions such as whether i) TCS occurrence is consistent within a single STP and between different STPs, ii) TCS transformation is a factor of wastewater and sludge treatment, iii) TCS degradation occurs in aerobic/anaerobic sludge digestion, iv) TCS adsorption is predictable and obeys any equilibrium and kinetics model. Two gas chromatography-mass spectrometry (GC-MS) based-methods were successfully developed for determination of TCS, 2,4-DCP, 2,8-DCDD and MTCS in wastewater and sludge. In the first method, liquid-liquid extraction (LLE) and silica column chromatography were applied for the extraction and cleanup of wastewater. In the second method, accelerated solvent extraction (ASE) and multilayer silica column chromatography were employed for the extraction and cleanup of sludge. For validation purpose, the methods were successfully applied to wastewater and sludge samples from three different municipal sewage treatment plants (STPs) in Hong Kong. Satisfactory mean recoveries for all target compounds were obtained as over 82% and 84% for wastewater and sludge samples, respectively. TCS degradation products were detected based on the treatment practice. 2,8-DCDD was detected in the plant utilizing UV disinfection at the mean level of 20.3(±4.8) ng.L-1. 2,4-DCP was identified in chemically enhanced primary treatment (CEPT) applying chlorine disinfection at the mean level of 64.5(±4.5) ng.L-1. Besides, MTCS was detected in the wastewater collected after biological treatment 33.3(±3.4) ng.L-1 as well as in sludge samples that have undergone aerobic digestion at the mean level of 266.1 (±14.2) ng.g-1 dry weight (d.w.). Mass balance of TCS in three STPs and the extent of TCS transformation to the degradation compounds were investigated and adsorption behavior of some of the occurred compounds was studied. Moreover, TCS fate was probed in full scale plant during wastewater and sludge aerobic/anaerobic treatment condition. Finally few correlations were investigated. For STP (I), 77.6% of the entering TCS mass flux to the plant was directly discharged to the receiving environment. The mass that was settled along the sludge underwent aerobic digestion treatment of which 52.2% was aerobically degraded in the digester. However 5.4% of the TCS in the sludge was observed to be transformed to MTCS and 47.8% was remained in the dewatered sludge to be disposed to landfill. TCS elimination in STP (II) wastewater treatment was 25.5%. Chlorination could cause 5.3% of TCS loss during disinfection process. Nevertheless, still 68.7% of the loading TCS was discharged to the environment through wastewater. TCS mass flux in pretreatment and post treatment sludge was almost constant. For STP (III), 14.2% and 8% of initial TCS mass flux was adsorbed to primary and secondary sludge, respectively. Mass balance between TCS lost in the biological treatment, the mass adsorbed to the sludge and the effluent revealed that 44.0% of the initial TCS mass flux was biodegraded in biological treatment of which 19.8% was transformed to MTCS. In addition, 10.3% of TCS mass was lost in UV irradiation disinfection unit of which 90.8% was transformed to 2,8-DCDD. Significant TCS mass loss (20.6%) was observed in anaerobic digestion of sludge and the remaining mass in dewatered sludge was disposed to landfill. No other degradation product was observed in the dewatered sludge except MTCS that showed insignificant change in mass flux after anaerobic digestion. Kd values were calculated for TCS, MTCS and 2,4-DCP for the first time based on the concentration of target compound in liquid and solid phase. Moreover, temporal-based variation of TCS and its degradation products were statistically proved. A relationship was attributed between TCS fraction adsorbed to the particulates in raw wastewater and elimination efficiency in primary treatment (r = 0.83, 0.66 and 0.87 for STP (I), (II) and (III), respectively). Adsorption behavior of TCS, 2,4-DCP and MTCS to primary and secondary sludge was investigated. For this purpose, a simple and efficient GC-MS-based method was developed for simultaneous determination of TCS, MTCS and 2,4-DCP in wastewater. Batch experiments were carried out and effect of various parameters such as pH, temperature and sludge concentration were studied. Three isotherm models, Linear, Freundlich and Langmuir were examined to fit the adsorption data. Amongst, Linear and Freundlich isotherm models were able to describe the system behavior well while Langmuir isotherm model did not exhibit satisfactory result. Relevant Kd values were derived for three compounds and were compared to the full scale. Pseudo-first and second order kinetics models were applied to describe the kinetic data. Pseudo-second order kinetic was found to fit well over the range of applied initial concentrations based on the regression coefficients and the relative error for the calculated equilibrium sorption capacity which implied the sorption of TCS, MTCS and 2,4-DCP onto the inactivated dried sludge proceeds predominantly through a pseudo-second order kinetics.

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Padua, Roberto R. "Purification and characterization of an antimicrobial compound secreted by a soil bacterium /." Abstract Full Text (HTML) Full Text (PDF), 2008. http://eprints.ccsu.edu/archive/00000530/02/1979FT.htm.

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Thesis (M.A.) -- Central Connecticut State University, 2008.
Thesis advisor: Michael A. Davis. "... in partial fulfillment of the requirements for the degree of Master of Arts in Biomolecular Sciences." Includes bibliographical references (leaves 36-39). Also available via the World Wide Web.

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Gedikoglu, Ayca Clarke Andrew Douglas. "Effect of antimicrobial agents on physical, chemical and microbiological characteristics of ready-to-eat bologna." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/5777.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed September 24, 2009). Thesis advisor: Dr. Andrew D. Clarke. Includes bibliographical references.

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Tsoi, Hoi-wah. "Effect of antibiotics on the immune response induced by live-attenuated Salmonella typhi /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2121315X.

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30

Wicht, Merrill Margaret. "Oleanolic acid: its isolation and derivatisation to potential antimicrobial compounds." Thesis, Cape Peninsula University of Technology, 2007. http://hdl.handle.net/20.500.11838/738.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2007
An increasing number of natural products possessing the oleanolic acid moiety have been shown to demonstrate a wide spectrum of biological activity. This thesis deals with the extraction and isolation of oleanolic acid from Syzigium aromaticum and the examination of its stereochemistry and crystal structure by X-ray diffraction. The synthetic routes used for converting functional groups on the oleanolic acid molecule to afford derivatives are described in Chapter 5. Oleanolic acid and its derivatives were evaluated for antimicrobial activity. Three different procedures viz. Kirby-Bauer, Broth dilution and Tetrazolium salt chemosensitivity were used. Acceptable results were obtained from the last method and these were used to arrive at conclusions regarding this study.

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31

Lindbäck, Emma. "Mechanisms of resistance to ciprofloxacin in Neisseria gonorrhoeae." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-688-3/.

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32

McBride, Kent Alexander. "An in vitro assessment of an engineered cationic antimicrobial peptide (eCAP) against planktonic strains of E. faecalis." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5241.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains viii, 33 p. : col. ill. Vita. Includes abstract. Includes bibliographical references (p. 26-31).

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33

Riesbeck, Kristian. "Effects of fluoroquinolones on the immune system." Malmö : Dept. of Medical Microbiology, Lund University, Malmö General Hospital, 1994. http://books.google.com/books?id=-hRtAAAAMAAJ.

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34

Wahyuono, Subagus. "Potential anti-infective agents isolated from Artemisia pacifica Nutt and Guardiola platyphylla Gray (fam. Asteraceae)." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185386.

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The dichloromethane extracts (1 mg/ml) of Artemisia pacifica Nutt and Guardiola platyphylla Gray (fam. Asteraceae) separately demonstrated in vitro growth inhibition of Staphylococcus aureus (UA 9-29), Bacillus subtilis (UA 2-27), Klebsiella pneumoniae (UA 3-9) and Candida albicans (UA 97). Each of these extracts were subjected to bioassay-directed solvent extraction and partition in order to obtain concentrated active fractions. Subsequently, the active compounds were isolated and identified from these fractions. Artemisia pacifica Nutt. The active compound was the major component isolated from A. pacifica. By comparing the physical and chemical data with previously reported data, this compound was identified as dehydrofalcarindiol. Dehydrofalcarindiol demonstrated growth inhibition against S. aureus (50 μg/ml), B. subtilis (25 μg/ml), K. pneumoniae (100 μg/ml) and C. albicans (25 μg/ml). Its diacetyl derivative was devoid of activity at 100 μg/ml. Guardiola platyphylla Gray. The active fraction obtained from G. platyphylla contained unstable compounds that decomposed in the presence of air. Size exclusion chromatography (Sephadex LH-20) was used to fractionate the active fraction. Two new sesquiterpenes, the o-catechol derivatives (1S,4S) and (1S,4R)-7,8-dihydroxy-11,12-dehydrocalamenene, were eluted from the column as a mixture. The mixture of their diacetyl derivatives was oxidized with CrO₃ in AcOH. The major oxidation product was identified as (1S)-7,8-diacetyl-4-oxodeisopropylcalamenene, thereby verifying the sole difference to be the configuration at C-4. This sesquiterpene mixture completely inhibited the growth of S. aureus (100 μg/ml), B. subtilis (50 μg/ml), K. pneumoniae (100 μg/ml) and C. albicans (100 μg/ml). After removal of the sesquiterpenes from the active fraction, the remaining compounds displayed the same level of activity. Another six compounds were also isolated from this mixture as acetylated derivatives due to their instability. Their dimeric structures were identified by 2D-NMR techniques (COSY, HETCOR and NOESY). These dimers may be artifacts since they were formed from their o-quinone monomers when kept at room temperature for a week or when heated at 60°C for 4 hours.

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35

Chia, Brian Cheng San. "Amphibian antimicrobial peptides : their structures and mechanisms of action : a thesis presented for the degree of Doctor of Philosophy." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phc532.pdf.

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Copy of author's previously published works inserted. Bibliography: leaves 183-220. Three antimicrobial peptides, maculatin 1.1, uperin 3.6 and caerin 4.1 have been isolated from the respective skin glands of the Australian amphibians Litoria genimaculata, Uperoleia mjobergii and Litoria caerulea. To gain a deeper insight into their mechanisms of action, three dimensional structural studies have been conducted using circular dichroism, two-dimensional nuclear resonance and computer modelling techniques. The role of central flexibility within antibiotic peptides in their interaction with bacterial membranes is also discussed.

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36

Dudley, Dawn M. "HIV-1 Env impacting HIV-1 fitness, entry inhibitor drug sensitivity, and in vivo selection of a resistant virus to the microbicide PSC-Rantes /." Connect to text online, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1186757280.

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Thesis (Ph. D.)--Case Western Reserve University, 2007.
[School of Medicine] Department of Molecular Biology and Microbiology. Includes bibliographical references. Available online via OhioLINK's ETD Center.

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37

Neetoo, Swaleha Hudaa. "Effectiveness of antimicrobial packaging in controlling the growth of Listeria monocytogenes on cold-smoked salmon." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 131 p, 2007. http://proquest.umi.com/pqdweb?did=1338870431&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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38

Jalal, Shah. "Molecular mechanisms of fluoroquinolone resistance in Pseudomonas aeruginosa /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4447-4/.

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39

Ho, Wing-yin Queenie, and 何穎賢. "Antimicrobial use & resistance in China: implications for public health in Hong Kong : an exploratoryanalysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46937092.

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40

Anyaogu, Kelechi C. "Stabilized metal nanoparticle-polymer composites preparation, characterization and potential applications /." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1222126708.

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41

Liu, Meilin. "Effects of the antimicrobial agent Triclosan on bacterial resistance to disinfection in wastewater treatment processes." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5996.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains viii, 55 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 52-55).

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42

Martini, Nataly Dominica. "The isolation and characterisation of antibacterial compounds from Combretum erythrophyllum (Burch.) Sond." Diss., Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-07092002-153815/.

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43

Barreto, Michael. "Antimicrobial activity of macroalgae from Kwazulu-Natal, South Africa, and the isolation of a bioactive compound from Osmundaria serrata (Rhodophyta)." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-09052005-095635/.

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44

Wicht, Merril Margaret. "Oleanic acid: its isolation and derivatisation to potential antimicrobial compounds." Thesis, Cape Peninsula University of Technology, 2007. http://hdl.handle.net/20.500.11838/732.

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A thesis submitted to the Cape Peninsula University of Technology in fulfilment of the requirements for the MASTERS DEGREE IN TECHNOLOGY (CHEMISTRY) Department of Chemistry January 2007
An increasing number of natural products possessing the oleanolic acid moiety have been shown to demonstrate a wide spectrum of biological activity. This thesis deals with the extraction and isolation of oleanolic acid from Syzigium aromaticum and the examination of its stereochemistry and crystal structure by X-ray diffraction. The synthetic routes used for converting functional groups on the oleanolic acid molecule to afford derivatives are described in Chapter 5. Oleanolic acid and its derivatives were evaluated for antimicrobial activity. Three different procedures viz. Kirby-Bauer, Broth dilution and Tetrazolium salt chemosensitivity were used. Acceptable results were obtained from the last method and these were used to arrive at conclusions regarding this study.

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45

Yang, Nan, and 楊楠. "Bismuth based agents and their interactions with the SARS helicase andits metal binding domain." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39634504.

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46

Oh, Herin. "Quinolone resistance in Bacteroides fragilis and Pseudomonas aeruginosa, two opportunistic pathogens /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-498-4.

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47

Singh, G. "Antibacterial activity testing of cotton medical textiles sonochemically impregnated with metal oxide nanoparticles." Thesis, Coventry University, 2014. http://curve.coventry.ac.uk/open/items/edeb833b-a792-49eb-bc22-bafbd374bb22/1.

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The Sonochemistry Centre at Coventry University is one of a group of organisations working on a project to develop a new technology for producing antimicrobial textiles. This technology involves the use of an ultrasonic process (sonochemical) to generate and impregnate fabrics with antibacterial metal oxide nanoparticles. The expectation is that these textiles can be produced at an affordable price for routine use in hospitals as uniforms, curtains, hospital bed sheets and linen. The aim of this PhD project was to assess the antibacterial activity of fabrics impregnated with ZnO and CuO NPs against a variety of Gram positive and Gram negative bacteria. The testing was principally carried out according to the absorption method from ISO 20743:2007. Research was also extended to compare different methods of assessing antibacterial activity of textile fabrics. These included disc diffusion tests and shake flask tests in saline or nutrient broth. Overall the results from absorption tests demonstrated that both the ZnO and CuO impregnated fabrics showed very good levels of antibacterial activity (A>2) against the test bacteria (Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa). During the optimisation of lab scale process to the pilot scale, two different types of CuO fabrics were produced to test and compare the antibacterial activity. One type of fabrics were impregnated with pre-made CuO nanoparticles by a ‘throwing the stones’ technology termed TTS and the other with sonochemically formed nanoparticles (in-situ), same as the lab process. The results indicated that the fabrics impregnated with sonochemically formed NPs displayed better antibacterial activity than the pre-made NPs. Leaching of the antibacterial agents in to saline was investigated using a shake flask method. CuO and ZnO coated fabrics prepared at laboratory scale were tested against Staphylococcus aureus, Acinetobacter baumannii and Escherichia coli. It was found that leachates prepared by shaking the fabrics in saline for 3 hours showed no antibacterial activity for CuO fabrics. However, leachates from ZnO fabrics showed an excellent activity after 24 ± 3 hours against all three bacterial species. Flow cytometry (FC) was investigated as an alternative to standard agar plate count (PC) methods for the determination of viable cell numbers. There was a general agreement between the results from agar plate counts and flow cytometry except that post incubation counts were greater with FC. The higher numbers of viable cells detected with FC may have been due to the presence of viable but not culturable cells (VBNC). Viable cells were observed by fluorescence microscopy in post incubation samples in which no viable cells were detected on nutrient agar plates. Cytotoxicity studies were conducted on ZnO and CuO fabrics from the pilot scale (both in-situ and TTS) against human dermal fibroblast cells (HDF) and human hepatocellular carcinoma cells (HepG2) using a MTT assay to determine cell viability. The results showed that ZnO and CuO are not toxic to HDF cells. However, cytotoxicity was seen in HepG2 cells with cell viability decreasing by > 14% for all the fabrics after 24 hours.

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Yang, Nan. "Bismuth based agents and their interactions with the SARS helicase and its metal binding domain." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39634504.

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Bernier, Bethany A. "Antimicrobial Effects of Blueberry Products Against Escherichia Coli O157:H7 in Liquid Medium and in Ground Beef." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/BernierBA2005.pdf.

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50

Altunakar, Bilge. "Food preservation by pulsed electric fields and selected antimicrobials." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Dissertations/Fall2007/b_altunakar_120507.pdf.

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Dissertations / Theses on the topic 'Anti-infective agents'

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