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Health hazards associated with dissemination of bacterial strains in waste water recycling /Rahman, Mokhlasur, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
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Population structure and antibiotic resistance of the genus enterococcus in humans, animals and the environment /Iversen, Aina, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 6 uppsatser.
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Interaction between waterborne pathogenic bacteria and Acanthamoeba castellanii /Abd, Hadi, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.
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A study of some of the bacteriological and chemical aspects of dead ends in Ann Arbor city water mains a disseration submitted in partial fulfillment ... Master of Science in Public Health ... /Eveland, Warren C. January 1939 (has links)
Thesis (M.S.P.H.)--University of Michigan, 1939.
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A study of some of the bacteriological and chemical aspects of dead ends in Ann Arbor city water mains a disseration submitted in partial fulfillment ... Master of Science in Public Health ... /Eveland, Warren C. January 1939 (has links)
Thesis (M.S.P.H.)--University of Michigan, 1939.
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Investigating the efficacy of medium pressure UV and hydrogen peroxide as on-farm treatment methods to reduce the microbial load of irrigation waterKotze, Madelize J. 04 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Many South African farmers are forced to use water from nearby rivers for crop irrigation, since it is
the most affordable and sometimes only source of water available to them. During this research
project, a baseline study was performed on a farm irrigating fresh produce with water obtained
from the Eerste River. The baseline study was done over a five month period, at six preselected
sampling points, to determine the microbial and physico-chemical parameters of the water so a
baseline could be established to compare the results to when the ultraviolet (UV) apparatus was
installed (February 2013). Aerobic colony count (ACC), total coliforms (TC) and Escherichia coli
(E. coli) were tested for during the microbiological study, while the physico-chemical analysis
comprised of temperature, pH, conductivity, chemical oxygen demand (COD), alkalinity and total
soluble solids (TSS). The UV treatment study was also performed over a five month timeline, at
eight different sampling points (original six sampling points, with additional sampling points before
and after UV). The same microbiological tests were performed during the UV treatment study, but
turbidity and percentage ultraviolet transmittance (% UVT) were performed additionally during
physico-chemical analysis.
During the baseline study ACC, TC and E. coli counts as high as 9 600 cfu.mL-1, 13 799
MPN.100 mL-1 and 2 098 MPN.100 mL-1 were isolated at the river (Sampling Point 1), respectively.
While performing the UV treatment study ACC, TC and E. coli counts as high as 142 000 cfu.mL-1,
241 960 MPN.100 mL-1 and 6 867 MPN.100 mL-1 were isolated at the river, respectively. As a
result it was concluded that the Eerste River was mostly unsuitable for irrigation of fresh produce
that are consumed raw. The higher counts in the river, during the UV treatment study might be
attributed to the increase in rainfall that occurred in the sampling months (March to July 2013).
The counts as measured at the point of irrigation are considered of greater importance,
since the counts present in the river might still decrease to below the guideline levels after passing
through sand filters and the addition of hydrogen peroxide (current mode of treatment) or after
passing through the UV in the UV treatment study. The ACC, TC and E. coli counts during the
baseline study were as high as 8 800 cfu.mL-1, 24 196 MPN.100 mL-1 and 85 MPN.100 mL-1 at the
point of irrigation (Sampling Point 6), respectively. After hydrogen peroxide addition average logreductions
ranging between 0.65 and 1.13 were seen, but reduction was never constant. The counts at the point of irrigation remained more or less constant compared to the river
due to contamination that occurred at the sand filters, making the water unsuitable for irrigation of
fresh produce in terms of ACC and TC counts. In the UV treatment study ACC, TC and E. coli
counts were as high as 35 000 cfu.mL-1, 10 462 MPN.100 mL-1 and 63 MPN.100 mL-1 at the point
of irrigation (Sampling Point 8), respectively. Average log-reductions in the range of 0.90 to 1.25
were achieved, but it was inconsistent. After treatment with chlorine and re-sanding of the sand
filters, no further contamination occurred and counts decreased to below guideline limits, making
the water safe for irrigational use in terms of all of the microbiological parameters. Not only is UV treatment more effective in reducing microbiological counts than H2O2, it is also relatively less
expensive in the long term. Hydrogen peroxide treatment of water amounts to a very high capital
expense every month, whereas UV may seem expensive when starting up, but the monthly
operating cost thereafter is marginally less than for H2O2.
It is of great importance to farmers to find a treatment that would reduce the counts in the
river water to below the guideline limits required for safe irrigation since pathogens can be carried
over from water onto fresh produce, resulting in an increase in produce-associated foodborne
outbreaks and loss of consumer trust. / AFRIKAANSE OPSOMMING: Menigte Suid-Afrikaners is afhanklik van nabygeleë riviere om hulle oeste te besproei aangesien
dit meestal die mees bekostigbare en soms enigste bron tot hul beskikking is. Tydens hierdie
projek is ‘n grondslag sowel as ‘n UV behandelingsmetode studie uitgevoer op ‘n plaas wat vars
vrugte en groente besproei met water water wat hul vanuit die Eersterivier verkry. Die
grondslagstudie is oor ‘n tydperk van vyf maande uitgevoer by ses voorafgekose punte. Dit is
gedoen om die mikrobiologiese sowel as chemiese parameters van die water te bepaal sodat ‘n
grondslag beskikbaar kon wees om met resultate te vergelyk wat met behulp van die
ultravioletmasjien verkry is (in Februarie 2013 geïnstalleer). Tydens die mikrobiologiese studie is
daar vir aerobiese koliform tellings (ACC), totale koliforme (TC) en Escherichia coli (E. coli)
getoets. Tydens die chemiese analise is temperatuur, pH, konduktiwiteit, chemiese suurstof
benodiging, alkaliniteit en totale oplosbaie vastestowwe in die water getoets. Die UV
behandelingsmetode studie is ook oor ‘n tydperk van vyf maande uitgevoer, met twee addisionale
toetspunte by. Presies dieselfde mikrobiologiese analises as wat tydens die grondslag studie
uitgevoer is, is tydens die UV behandelingsmetode studie uitgevoer, maar vir die chemiese analise
het turbiditeit en persentasie ultraviolet transmissie van die water bygekom.
Gedurende die grondslag studie was ACC, TC and E. coli tellings so hoog as 9 600
cfu.mL-1, 13 799 MPN.100 mL-1 en 2 098 MPN.100 mL-1 onderskeidelik uit die rivier geïsoleer
(Punt 1). Tydens die UV behandelingsmetode studie was ACC, TC en E. coli tellings so hoog as
142 000 cfu.mL-1, 241 960 MPN.100 mL-1 en 6 867 MPN.100 mL-1 onderskeidelik by die rivier
geïsoleer. Gevolglik is daar afgelei dat die Eersterivier se water meestal ongeskik is om te gebruik
vir die besproeiing van vars groente en vrugte wat rou geëet word sonder dat enige verdere
behandeling plaasvind. Die hoër tellings wat tydens die UV behandelingsmetode in die rivier
sigbaar was kan hoofsaaklik toegeskryf word aan die toename in reënval in daardie tyd (Maart tot
Julie 2013).
Tellings soos gemeet by die punt van besproeiing is wel van groter belang as die wat
aangeteken is by die rivier; aangesien die tellings wat in die rivier aangeteken is steeds kan
afneem tot onder aanvaarbare hoeveelhede soos in die standaarde uiteengesit, want die water
moet steeds deur sandfilters beweeg en word ook huidiglik deur waterstofperoksied behandel
tydens die die grondslagstudie of beweeg deur die UV apparaat in die UV behandelingsmetode
studie. Die ACC, TC en E. coli tellings soos gemeet by die besproeiingspunt (Punt 6) was so hoog
as 8 800 cfu.mL-1, 24 196 MPN.100 mL-1 en 85 MPN.100 mL-1, onderskeidelik. Na
waterstofperoksied byvoeging was die gemiddelde log-reduksies sigbaar, tussen 065 en 1.13,
maar afnames was nooit konstant nie. Die tellings by die punt van besproeiing het ongeveer
konstant gebly in vergelyking met die tellings wat by die rivier aangeteken is; moontlik as gevolg
van die hoë kontaminasie vlakke in die sandfilters. Kontaminasie van sandfilters het veroorsaak
dat die water ongeskik was vir die gebruik van besproeiing van vars groente as gevolg van die hoë ACC en TC vlakke. Tydens die UV behandelingsmetode studie is ACC, TC en E. coli tellings so
hoog as 35 000 cfu.mL-1, 10 462 MPN.100 mL-1 en 63 MPN.100 mL-1, onderskeidelik aangeteken
(Punt 8). Gemiddelde log-reduksies tussen 0.90 tot 1.25 was verkry, maar behandeling en
afnames in tellings was nie konstant nie. Nadat die sandfilters met chloor behandel is en die sand
daarin vervang is, het geen verdere kontaminasie by die punt voorgekom nie. Nadat al die
voorafgenoemde behandelings afgehandel is, het die tellings tot laer as die van die standaarde
gedaal en dus was die water nou veilig om te gebruik vir besproeiingsdoeleindes in terme van die
mikrobiologiese parameters. Die UV behandelingsmetode is nie net meer effektief in die verlaging
van mikrobiologiesese tellings as waterstofperoksied nie, dis ook heelwat goedkoper in die
langtermyn. Waterstofperoksied behandeling van water lei tot ‘n baie hoë kapitale onkoste per
maand, terwyl UV baie duur mag voorkom in die beginfase, maar die maandelikse kostes is
aansienlik laer as die van waterstofperoksied en maak sodoende op daarvoor.
Dit is van uiterste belang vir boere om ‘n water behandelingsmetode te vind wat die hoë
tellings in die rivier sal afbring tot laer as Suid-Afrikaanse en Kanadese riglyne; aangesien
patogene oorgedra kan word van vars vrugte en groente. Laasgenoemde kan tot ‘n drastiese
toename in vars voedsel geassosieerde siektes en gevolglik ‘n afname in die vertroue wat ‘n kliënt
in ‘n produk plaas, lei.
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Virulência e resistência antimicrobiana de Enterococcus sp. isolados de amostras de água / Virulence and antimicrobial resistance of Enterococcus sp. isolated from water samplesRoberto, Sharise Beatriz 17 December 2015 (has links)
Capes / Enterococcus sp. são bactérias caracterizadas como cocos Gram-positivos, frequentemente encontradas na microbiota normal do trato gastrointestinal de humanos e animais, além de serem encontradas em plantas, solo e na superfície da água. Embora sejam considerados microrganismos comensais, Enterococcus sp. podem estar relacionados a uma grande variedade de infecções humanas, e com o rápido crescimento de cidades, muitas vezes sem saneamento básico, a água de superfície serve como disseminação de doenças de veiculação hídrica. Este trabalho apresenta como objetivo, o isolamento e identificação de espécies de Enterococcus de água de superfície da nascente do córrego Jaboti e sua foz, ribeirão Biguaçu e represa do Barreiro, na cidade de Apucarana – PR, além da determinação da sensibilidade desta bactéria a antimicrobianos e fatores de virulência. Os enterococos isolados foram testados quanto à sua resistência a 12 antibióticos através do método de disco difusão, além de análises genotípicas de fatores de virulência e de resistência a antimicrobianos, utilizando a reação em cadeia da polimerase (PCR). Foram confirmados quarenta (40) isolados para o gênero Enterococcus, sendo que as espécies identificadas foram E. italicus (n= 8); E. casseliflavus e E. flavescens (n= 4); E. gallinarum (n= 4); E. seriolicida (n= 3) e E. faecium (n= 2). As taxas de resistência dos isolados foram observadas em 57,5%; 55,0%; 50,0%; 47,5% e 35,0% para eritromicina, penicilina, teicoplanina, vancomicina e ampicilina respectivamente. Genes de resistência encontrados nos isolados foram vanA (37,5%), erm(B) (25,0%), aac (6’)-le-aph(2’’)-la (22,0%); tet(L) (20.0%) e tet(M) (2,5%). Nenhum dos isolados pesquisados apresentaram o gene vanB. Determinantes de virulência dos isolados foram detectados a uma taxa de 17,5 e 2,5% para asa1 e cylA. Não foram identificados os genes gelE, ace agg e cpd nos isolados analisados. A presença de Enterococcus sp. na água representa um problema de saúde pública, uma vez que esta pode servir como disseminação desta bactéria para seres humanos. / Enterococcus sp. are Gram-positive cocci bacteria often found in the normal microflora of the gastrointestinal tract of humans and animals; and also in plants, soil and surface water. Although these microorganisms are considered commensals, Enterococcus sp. can be related to a wide variety of human infections. With the rapid growth of cities, often without basic sanitation, surface water serves as the spread of waterborne diseases through the Enterococcus sp. This work presents as objective the isolation and identification of species of Enterococcus of surface water samples collected from three lakes: Jaboti, Lake Biguaçu and Lake Barreiro, all in the Apucarana City – PR. The virulence factors and sensitivity to antibiotics are were also determined. The isolates were tested for their resistance to 12 antibiotics by disk diffusion method; and the genotypic analysis of virulence factors and antimicrobial resistance genes was carried out using the Polymerase Chain Reaction (PCR). Forty (40) isolates for the genus Enterococcus were confirmed and species were identified as follows: E. italicus (n= 8); E. casseliflavus/E.flavescens (n= 4); E. gallinarum (n=4); E. seriolicida (n= 3) and E. faecium (n= 2). The resistance rates of the isolates were observed of 57,5%; 55,0%; 50,0%; 47,5% and 35,0% for erythromycin, penicillin, teicoplanin, vancomycin and ampicilin respectively. Genes found among isolates were vanA (37,5%); erm(B) (25,0%); aac (6 ') - aph-le (2') – la (22,5%); tet(L) (20,0%) and tet(M) (2,5%). None of the studied isolates presented vanB gene. Virulence determinants of the isolates were detected at a rate of 17,5 and 2,5% for asa1 and cylA. The genes gelE, agg, ace and cpd were not detected among the isolates. The presence of Enterococcus sp. in water is a public health problem since it can spread virulent and antibiotic resistant bacteria to humans.
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Potencial citotóxico e virulência de Enterococcus sp. isolados de ambiente aquático / Cytotoxic potential and virulence of Enterococcus sp. isolated from aquatic environmentMikalouski, Udson 02 March 2017 (has links)
Capes / Enterococcus spp. pertencem ao grupo das bactérias láticas e estão presentes em solos, águas, plantas, microbiota autóctone de vários alimentos e como membros da microbiota intestinal de humanos e animais. Esses microrganismos foram considerados por muito tempo como comensais, mas o aumento da severidade das infecções nosocomiais causadas por enterococos multirresistentes a antimicrobianos e, a falta de conhecimento sobre seus fatores de virulência geram insegurança para saúde pública. Nosso estudo objetivou avaliar a capacidade citotóxica, resistência e virulência de Enterococcus sp. provenientes de ambientes aquáticos. Foram analisados a presença de genes de resistência à vancomicina (vanA e vanB) e de virulência como produção de gelatinase (gelE), adesina de colágeno de Enterococcus (ace), bacteriocinas ativadoras de citolisina (cylA), serina endopeptidase (sprE), ilha de patogenicidade (PAI), substância de agregação (asa1), feromônio sexual (cpd), substância de agregação (agg) e teste fenotípicos de resistência a antibióticos, citotoxidade em células HeLa e formação de biofilme. Todos os isolados apresentaram capacidade de formar biofilme e potencial citotóxico com intensidades distintas, e 66,66% dos isolados apresentaram resistência à vancomicina e 58% à ampicilina. Um isolado de E. casseliflavus apresentou resistência a todos os antibióticos testados, além de capacidade de formar biofilme e apresentar potencial citotóxico. As espécies de Enterococcus sp. analisadas apresentaram características independentes, o que reforça a importância dos estudos nos mais variados ambientes. / Enterococcus spp. belong to the group of lactic bacteria and are present in soils, waters, plants, autochthonous microbiota of various foods and as members of the intestinal microbiota of animals and animals. These microorganisms have been observed as commensals for a long time, but the increased of severity nosocomial infections caused by multi-resistant antimicrobial enterococci and a lack of knowledge about their virulence factors generate insecurity for public health. Our study aimed to evaluate the cytotoxic capacity, resistance and virulence of Enterococcus sp. that comes from aquatic environments. It was studied resistence genes to AVancomycin (vanA and vanB) and virulence as gelatine production (gelE), collagen adhesion of Enterococcus (ace), bacteriocins cytolysin-activating (cylA), endopeptidase serine (sprE), and pathogenicity islands (PAI), aggregation substance (asa1), sexual pheromone (cpd), agglutination substance (agg) and phenotypic test of resistance to antibiotics, cytotoxicity in HeLa cells and biofilm formation. All the isolates presented biofilm capacity and cytotoxic potential with different intensities, and 66.66% of the isolates presented resistance to vancomycin and 58% to ampicillin. An E. casseliflavus isolate shows resistance to all antibiotics tested, as well as biofilm formation and cytotoxic potential. The species of Enterococcus sp. analyzed presented independent characteristics, which reinforce the importance of studies in the most varied environments.
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Potencial citotóxico e virulência de Enterococcus sp. isolados de ambiente aquático / Cytotoxic potential and virulence of Enterococcus sp. isolated from aquatic environmentMikalouski, Udson 02 March 2017 (has links)
Capes / Enterococcus spp. pertencem ao grupo das bactérias láticas e estão presentes em solos, águas, plantas, microbiota autóctone de vários alimentos e como membros da microbiota intestinal de humanos e animais. Esses microrganismos foram considerados por muito tempo como comensais, mas o aumento da severidade das infecções nosocomiais causadas por enterococos multirresistentes a antimicrobianos e, a falta de conhecimento sobre seus fatores de virulência geram insegurança para saúde pública. Nosso estudo objetivou avaliar a capacidade citotóxica, resistência e virulência de Enterococcus sp. provenientes de ambientes aquáticos. Foram analisados a presença de genes de resistência à vancomicina (vanA e vanB) e de virulência como produção de gelatinase (gelE), adesina de colágeno de Enterococcus (ace), bacteriocinas ativadoras de citolisina (cylA), serina endopeptidase (sprE), ilha de patogenicidade (PAI), substância de agregação (asa1), feromônio sexual (cpd), substância de agregação (agg) e teste fenotípicos de resistência a antibióticos, citotoxidade em células HeLa e formação de biofilme. Todos os isolados apresentaram capacidade de formar biofilme e potencial citotóxico com intensidades distintas, e 66,66% dos isolados apresentaram resistência à vancomicina e 58% à ampicilina. Um isolado de E. casseliflavus apresentou resistência a todos os antibióticos testados, além de capacidade de formar biofilme e apresentar potencial citotóxico. As espécies de Enterococcus sp. analisadas apresentaram características independentes, o que reforça a importância dos estudos nos mais variados ambientes. / Enterococcus spp. belong to the group of lactic bacteria and are present in soils, waters, plants, autochthonous microbiota of various foods and as members of the intestinal microbiota of animals and animals. These microorganisms have been observed as commensals for a long time, but the increased of severity nosocomial infections caused by multi-resistant antimicrobial enterococci and a lack of knowledge about their virulence factors generate insecurity for public health. Our study aimed to evaluate the cytotoxic capacity, resistance and virulence of Enterococcus sp. that comes from aquatic environments. It was studied resistence genes to AVancomycin (vanA and vanB) and virulence as gelatine production (gelE), collagen adhesion of Enterococcus (ace), bacteriocins cytolysin-activating (cylA), endopeptidase serine (sprE), and pathogenicity islands (PAI), aggregation substance (asa1), sexual pheromone (cpd), agglutination substance (agg) and phenotypic test of resistance to antibiotics, cytotoxicity in HeLa cells and biofilm formation. All the isolates presented biofilm capacity and cytotoxic potential with different intensities, and 66.66% of the isolates presented resistance to vancomycin and 58% to ampicillin. An E. casseliflavus isolate shows resistance to all antibiotics tested, as well as biofilm formation and cytotoxic potential. The species of Enterococcus sp. analyzed presented independent characteristics, which reinforce the importance of studies in the most varied environments.
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Estudo dos metodos : floculação em carbonato de calcio e adaptação das tecnicas de filtração em membrana e separação imunomagnetica para a detecção de Cryptosporidium e Giardia em amostras hidricas / Methods studies : calcium carbonate floculation and adptation of membrane filtration and immunomagnetic separation techniques for Cryptosporidium and Giardia detection in water samplesCantusio Neto, Romeu 28 March 2008 (has links)
Orientador: Regina Maura Bueno Franco / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T22:08:19Z (GMT). No. of bitstreams: 1
CantusioNeto_Romeu_D.pdf: 1288923 bytes, checksum: 6747f006dc8fe56fe9a7284e80649fe0 (MD5)
Previous issue date: 2008 / Resumo: A veiculação hídrica tem sido considerada uma das principais vias de transmissão de giardiose e criptosporidiose sendo implicada na ocorrência de vários surtos de gastroenterites, em vários países nos últimos anos. Diante deste panorama, no Brasil foi emitida Portaria 518/04 (Ministério da Saúde), que recomenda a pesquisa destes protozoários em água de consumo humano. Por este motivo, o objetivo deste estudo foi realizar um estudo comparativo entre as metodologias de concentração já existentes: Filtração em Membrana (FM) e Floculação em Carbonato de Cálcio (FCC), tecendo uma análise crítica das mesmas e verificando-se a sua aplicabilidade em amostras naturais de água superficial do Rio Atibaia. Este estudo foi conduzido em duas etapas: na primeira, foram realizados 52 experimentos, visando analisar o desempenho dos métodos propostos determinando-se a precisão inicial em amostras de água reagente inoculadas com suspensões comerciais de cistos e oocistos Easy Seed® (Biotecnology Frontiers, Austrália), aplicando-se ou não a etapa de purificação mediante o uso da separação imunomagnética. Quando foram avaliadas amostras do rio Atibaia, a suspensão comercial de cistos e oocistos utilizada para a contaminação artificial foi Color Seed® (Biotecnology Frontiers, Austrália). Em uma segunda etapa, um total de 36 experimentos foi conduzido com o objetivo de se avaliar o comportamento dos mesmos métodos frente a fatores interferentes, característicos da matriz de água bruta superficial, entre eles a turbidez. Nos experimentos controle com amostra de água reagente, a metodologia de FM recuperou mais organismos (21,5 % dos oocistos e 25,0 % dos cistos), quando comparada com a metodologia de FCC (5,3 % e 5,8 % dos oocistos e cistos, respectivamente). A inclusão da etapa de purificação por separação imunomagnética (IMS) não resultou num aumento na recuperação de cistos e oocistos nestas metodologias (FM e FCC). Nos experimentos com amostras de água do Rio Atibaia, de uma maneira geral, a metodologia de FCC apresentou melhor desempenho de recuperação dos organismos e quando incluída a etapa de IMS, uma melhora ocorreu apenas para a recuperação de cistos de Giardia spp. Quando avaliada amostras de água bruta superficial do rio Atibaia em condições de turbidez até 50 NTU a etapa de purificação por IMS acarretou uma maior eficiência de recuperação de cistos de Giardia spp. e oocistos de Cryptosporidium spp., para as duas metodologias de concentração. Quando a turbidez das amostras foi superior a 50 NTU, uma melhora da recuperação ocorreu apenas para Cryptosporidium spp, utilizando-se o método de FM. Assim, ambas as metodologias avaliadas, mostraram-se eficientes para serem aplicadas em um monitoramento desses protozoários em amostras hídricas, mesmo em situações de alta turbidez. A etapa de purificação pela separação imunomagnética nem sempre apresentou um ganho na recuperação dos organismos e, as variações nos valores de recuperação para ambos os protozoários, são inerentes aos protocolos utilizados e também associados à matriz analisada. A FM é indicada pela praticidade, tempo e resultados, podendo auxiliar para o conhecimento da ocorrência destes patógenos e assim, minimizar a possibilidade de sua transmissão mediante veiculação hídrica / Abstract: The waterborne transmission route of giardiosis and criptosporidiosis has been considered the major one, causing the occurrence of several gastroenteritis outbreaks in several countries in the last years. Looking to this panorama, was published in Brazil the Governmental Decree 518/04 (Health Department), that recommends the research of these protozoa in water samples. For this reason, the goal of this study was to accomplish a comparative study between Membrane Filtration (MF) and Calcium Carbonate Flocculation (FCC) concentration methodologies, doing a critical analysis of both and verifying its apply in natural samples of Atibaia River superficial water. Two stages took place: in the first one, 52 experiments were carried out, aiming to analyze the performance of the methods proposed, determining the initial precision in samples of reagent water inoculated with commercial suspensions of cysts and oocysts (Easy Seed®-Biotecnology Frontiers Australia), applying or not the purification step by Immunomagnetic Separation. When natural water samples were evaluated, the commercial suspension of cysts and oocysts utilized for the artificial contamination was (Color Seed®-Biotecnology Frontiers Australia). In a second step, 36 experiments were carried out aiming to evaluate the behavior of the methods facing interferential factors, peculiar of the superficial raw water matrix, as turbidity. In the trial control with reagent water sample, the FM methodology recovered more organisms (21.5% of the oocysts and 25.0% of the cysts), in comparison to the FCC methodology (5.3% of the oocysts and 5.8% of the cysts). The purification step by Immunomagnetic Separation (IMS) did not show an improvement in the recovery of cysts and oocysts in these methodologies (FM and FCC). In the experiments with natural water performance of the organisms and when IMS step was included, an improvement occurred just for the recovery of Giardia spp. cysts. When superficial raw water of Atibaia river samples with turbidity up to 50 NTU were evaluated, the purification step by IMS showed higher efficiency in the recovery of Giardia spp. cysts and Cryptosporidium spp. oocysts, for both concentration methodologies. When the turbidity of the sample was over 50 NTU, a recovery improvement occurred just for Cryptosporidium spp, using the FM method. Thus, both methodologies showed efficiency in monitoring these protozoa in water samples, even in situations of high turbidity. The purification step by Immunomagnetic Separation not always showed gain in the recovery of the organisms and the variations in the values of recovery for both protozoa are inherent to the protocols that were used and also associated to the analyzed matrix. However, the FM method is indicated for its practicability, time and results, being able to help the knowledge of the occurrence of these pathogens and minimize the possibility of its transmission by waterborne route / Doutorado / Parasitologia / Doutor em Parasitologia
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