Wyniki wyszukiwania - Biblioteka Nauki

1

Maillard neoglycans as inhibitors for in vitro adhesion of F4+ enterotoxigenic Escherichia coli to piglet intestinal cells

100%

Sarabia-Sainz H. , Mata Haro V. , Sarabia Sainz J. , Vázquez-Moreno L. , Montfort G.

Acta Biochimica Polonica

|

2017

|

tom 64

|

nr 4

679-686

EN

Adhesion of enterotoxigenic (ETEC) E. coli to host intestinal cells is mediated by lectin-like fimbriae that bind to specific glycan moieties on the surfaces of enterocytes. To prevent in vitro binding of E. coli F4 fimbriae (F4 ETEC+) to piglet enterocytes, neoglycans were synthesized by the Maillard reaction conjugating lactose (Lac), galacto-oligosaccharides (GOS) or chitin oligosaccharides (Ochit) to porcine serum albumin (PSA). Neoglycans were characterized by SDS-PAGE, intrinsic tryptophan fluorescence and recognition by plant lectins, as well as by F4 ETEC variants. Electrophoretic patterns suggested the binding to PSA of 63, 13 and 2 molecules of Lac, GOS and Ochit, respectively. All neoglycans displayed quenching of tryptophan fluorescence consistent with the degree of glycation estimated by SDS-PAGE. Plant lectins recognized the neoglycans according to their specificity, whereas antigenic variants of F4 ETEC (ab, ac and ad) recognized PSA-Ochit and PSA-Lac with higher affinity than that for GOS. Neoglycans partially hindered the in vitro binding of F4+ ETEC to piglet enterocytes in a dose-dependent manner. The most effective blocking was observed with PSA-Lac that partially inhibited the adhesion of bacteria to enterocytes in a dose dependent manner, as quantified by flow cytometry. Increased production of the cytokines IL-6 and TNF-α was observed in response to F4+ ETEC infection of enterocytes and production was reduced in the presence of PSA-Ochit and PSA-GOS. These results suggest that neoglycans synthesized by the Maillard reaction could be useful in the prophylaxis of diarrhea in piglets.

2

Escherichia Coli in Sewage Sludge - Detection Method / Escherichia Coli W Osadach Ściekowych - Metoda Wykrywania

89%

Machnicka A.

Chemistry-Didactics-Ecology-Metrology

|

2014

|

tom 19

|

nr 1-2

79-85

EN

Escherichia coli is Gram-negative optionally anaerobic roads which belongs to Enterobacteriaceae family. Includes in a physiological bacterial flora of human and warm-blooded animals large intestine. Escherichia coli is being met in abiotic elements of the environment so as waters, wastewater, sewage sludge, soil and the food. This bacterium is showing the pathogenicity in named terms for the peoples, triggering diseases mainly: gastrointestinal tract and urinary. Quality and quantitative proposed detections method of the bacteria E. coli contains five/six steps: - appointment dry suspended solid, - preparation averaged, test of sample and resuscitation of bacteria, - making dilutions, - enrichment and differentiation in chromogenic-selective medium, - enumerating the amount of cfu E. coli in 1 g of a dry weight, - optionally, the biochemical identification

PL

Escherichia coli jest Gram-negatywną, względnie beztlenową pałeczką należącą do rodziny Enterobacteriaceae. Wchodzi w skład fizjologicznej flory bakteryjnej jelita grubego człowieka oraz zwierząt stałocieplnych. Spotyka się ją w elementach abiotycznych środowiska, takich jak wody, ścieki, osady ściekowe, gleba i żywność. Bakteria ta w określonych warunkach wykazuje chorobotwórczość dla człowieka, wywołując głównie schorzenia układów pokarmowego i moczowego. Proponowana metoda jakościowa i ilościowa wykrywania bakterii E. coli zawiera pięć/sześć etapów: - oznaczenie suchej masy osadu, - przygotowanie próbki uśrednionej i badawczej oraz przywrócenie bakteriom aktywności fizjologicznej, - wykonanie rozcieńczeń, - namnażanie i identyfikacja na podłożu chromogennym-selektywnym, - wyliczenie ilości jtk E. coli w 1 g suchej masy osadu, - opcjonalnie identyfikacja biochemiczna.

3

Sanitary, Microbiological Condition, and Ecological State of Surface Water Quality in the Upper Siret River Basin (Ukraine)

88%

Burdenyuk I. , Masykevich А. , Dombrovskiy K. , Rylskyi O. , Masykevich Y. , Deyneka S. , Malovanyy M. , Tymchuk I.

Ecological Engineering & Environmental Technology

|

2023

|

tom Vol. 24, iss. 9

55--63

EN

This study aimed to spatially assess the ecological state of the upper Siret River basin in Ukraine, along with its main tributaries, using physicochemical and microbiological indicators. Additionally, we evaluated the impact of anthropogenic activities on surface water quality in the region. The research spanned one year, with nine sampling points ranging from the Siret River sources in the Pokutsko-Bukovynian Carpathians to the Romania border crossing area. Notably, a significant portion of the upper basin lies within the Vyzhnytskyi National Nature Park. Physicochemical analysis involved measuring pH, water turbidity, and concentrations of NH4+, NO3-, and CI- ions. Microbiological analysis focused on total and fecal bacteria, specifically E. coli species. Results revealed a significant correlation between population density, the absence of centralized sewage treatment facilities in large settlements, and the level of surface water pollution in the Ukrainian segment of the Siret River basin. The upper part of the river network, where the Vyzhnytskyi National Nature Park is located, displayed the cleanest waters. Downstream, surface water pollution increased, particularly near certain points outside large settlements and tourist complexes (Myhove, Berehomet, and Storozhynets). Our findings highlight the importance of using microbiological indicators to monitor the ecological state of Danube sources in the Eastern Carpathians.

4

Mutator specificity of Escherichia coli alkB117 allele

88%

Nieminuszczy J. , Janion C. , Grzesiuk E.

Acta Biochimica Polonica

|

2006

|

tom 53

|

nr 2

425-428

EN

The Escherichia coli AlkB protein encoded by alkB gene was recently found to repair cytotoxic DNA lesions 1-methyladenine (1-meA) and 3-methylcytosine (3-meC) by using a novel iron-catalysed oxidative demethylation mechanism that protects the cell from the toxic effects of methylating agents. Mutation in alkB results in increased sensitivity to MMS and elevated level of MMS-induced mutations. The aim of this study was to analyse the mutational specificity of alkB117 in a system developed by J.H. Miller involving two sets of E. coli lacZ mutants, CC101-106 allowing the identification of base pair substitutions, and CC107-CC111 indicating frameshift mutations. Of the six possible base substitutions, the presence of alkB117 allele led to an increased level of GC→AT transitions and GC→TA and AT→TA transversions. After MMS treatment the level of GC→AT transitions increased the most, 22-fold. Among frameshift mutations, the most numerous were -2CG, -1G, and -1A deletions and +1G insertion. MMS treatment appreciably increased all of the above types of frameshifts, with additional appearance of the +1A insertion.

5

Reverse osmosis as one-step wastewater treatment: a case study on groundwater pollution

88%

Ali W. , Rehman W. U. , Younas M. , Ahmad M. I. , Gul S.

Polish Journal of Chemical Technology

|

2015

|

tom Vol. 17, nr 4

42--48

EN

The present case study is focused on performance evaluation of a Reverse Osmosis (RO) membrane based pilot plant to treat the ground/surface drinking water sources polluted by flood, rivers and/or canals. The RO plant was designed, fabricated and then operated with polluted water. Two feed water samples having a TDS of 2.000 mg · L−1 and 10.000 mg · L−1 respectively, were taken and analyzed for physical, chemical and microbiological contaminants. The RO plant was run once through over a span of 100 hrs at an operating pressure of 15 bar. TDS rejections were found to be more than 94% while permeate flux was measured to be 25.82 L · m−2 · hr−1 to 40.55 L · m−2 · hr−1. Results show that RO plant has a potential to remove physical, chemical and microbiological contaminants like Total Coliform and E. Coli in one step.

6

Spontaneous mutagenesis in exponentially growing and stationary-phase, umuDC-proficient and -deficient, Escherichia coli dnaQ49.

75%

Nowosielska A. , Nieminuszczy J. , Grzesiuk E.

Acta Biochimica Polonica

|

2004

|

tom 51

|

nr 3

683-692

EN

Spontaneous mutations arise not only in exponentially growing bacteria but also in non-dividing or slowly dividing stationary-phase cells. In the latter case mutations are called adaptive or stationary-phase mutations. High spontaneous mutability has been observed in temperature sensitive Escherichia coli dnaQ49 strain deficient in 3'→5' proofreading activity assured by the ε subunit of the main replicative polymerase, Pol III. The aim of this study was to evaluate the effects of the dnaQ49 mutation and deletion of the umuDC operon encoding polymerase V (Pol V) on spontaneous mutagenesis in growing and stationary-phase E. coli cells. Using the argE3OC →Arg+ reversion system in the AB1157 strain, we found that the level of growth-dependent and stationary-phase Arg+ revertants was significantly increased in the dnaQ49 mutant at the non-permissive temperature of 37°C. At this temperature, in contrast to cultures grown at 28°C, SOS functions were dramatically increased. Deletion of the umuDC operon in the dnaQ49 strain led to a 10-fold decrease in the level of Arg+ revertants in cultures grown at 37°C and only to a 2-fold decrease in cultures grown at 28°C. Furthermore, in stationary-phase cultures Pol V influenced spontaneous mutagenesis to a much lesser extent than in growing cultures. Our results indicate that the level of Pol III desintegration, dependent on the temperature of incubation, is more critical for spontaneous mutagenesis in stationary-phase dnaQ49 cells than the presence or absence of Pol V.

7

Isolation of bacteria from soil sample of Tamil Nadu and their in vitro interaction

75%

Sankari D. , Khusro A. , Aarti C.

World News of Natural Sciences

|

2020

|

tom 28

67-75

EN

The present study was investigated to determine the competitive interaction between Gram positive (B. subtilis) and Gram negative (P. aeruginosa and E. coli) bacteria in vitro. Bacteria of interest were isolated from soil sample and were identified through morphological and biochemical tests. Bacterial cultures were grown alone and as co- culture in test tubes containing sterile broth. Bacterial growth and their growth inhibition in co- culture tubes were analyzed till 96 h through spectrophotometric assay and colony forming unit (CFU) assay. Spectrophotometric analysis and CFU/mL assay showed that the effect of B. subtilis on P. aeruginosa and E. coli in co- culture tubes was growth inhibitory. This is accompanied by the reduction in absorbance value and CFU/mL of the co-culture tubes. The bactericidal activity of B. subtilis was measured on P. aeruginosa and E. coli using agar well diffusion method. B. subtilis showed zone of inhibition of 8 mm and 6 mm against P. aeruginosa and E. coli, respectively. The antagonistic activity test of B. subtilis favoured the spectrophotometric and colony forming assay results. These results suggest that B. subtilis develop adaptational pathways by extracellular signaling molecules and antibacterial factors in order to compete with bacterial neighbors.

8

Integrated optical biosensor for rapid detection of bacteria

75%

Mathesz A. , Valkai S. , Újvárosy A. , Aekbote B. , Sipos O. , Stercz B. , Kocsis B. , Szabó D. , Dér A.

Optofluidics, Microfluidics and Nanofluidics

|

2015

|

tom 2

|

nr 1

EN

In medical diagnostics, rapid detection of pathogenic bacteria from body fluids is one of the basic issues. Most state-of-the-art methods require optical labeling, increasing the complexity, duration and cost of the analysis. Therefore, there is a strong need for developing selective sensory devices based on label-free techniques, in order to increase the speed, and reduce the cost of detection. In a recent paper, we have shown that an integrated optical Mach-Zehnder interferometer, a highly sensitive all-optical device made of a cheap photopolymer, can be used as a powerful lab-on-a-chip tool for specific, labelfree detection of proteins. By proper modifications of this technique, our interferometric biosensor was combined with a microfluidic system allowing the rapid and specific detection of bacteria from solutions, having the surface of the sensor functionalized by bacterium-specific antibodies. The experiments proved that the biosensor was able to detect Escherichia coli bacteria at concentrations of 106 cfu/ml within a few minutes, that makes our device an appropriate tool for fast, label-free detection of bacteria from body fluids such as urine or sputum. On the other hand, possible applications of the device may not be restricted to medical microbiology, since bacterial identification is an important task in microbial forensics, criminal investigations, bio-terrorism threats and in environmental studies, as well.

9

Effect of SOS-induced Pol II, Pol IV, and Pol V DNA polymerases on UV-induced mutagenesis and MFD repair in Escherichia coli cells.

75%

Wrzesiński M. , Nowosielska A. , Nieminuszczy J. , Grzesiuk E.

Acta Biochimica Polonica

|

2005

|

tom 52

|

nr 1

139-147

EN

Irradiation of organisms with UV light produces genotoxic and mutagenic lesions in DNA. Replication through these lesions (translesion DNA synthesis, TSL) in Escherichia coli requires polymerase V (Pol V) and polymerase III (Pol III) holoenzyme. However, some evidence indicates that in the absence of Pol V, and with Pol III inactivated in its proofreading activity by the mutD5 mutation, efficient TSL takes place. The aim of this work was to estimate the involvement of SOS-inducible DNA polymerases, Pol II, Pol IV and Pol V, in UV mutagenesis and in mutation frequency decline (MFD), a mechanism of repair of UV-induced damage to DNA under conditions of arrested protein synthesis. Using the argE3→Arg+ reversion to prototrophy system in E. coli AB1157, we found that the umuDC-encoded Pol V is the only SOS-inducible polymerase required for UV mutagenesis, since in its absence the level of Arg+ revertants is extremely low and independent of Pol II and/or Pol IV. The low level of UV-induced Arg+ revertants observed in the AB1157mutD5ΔumuDC strain indicates that under conditions of disturbed proofreading activity of Pol III and lack of Pol V, UV-induced lesions are bypassed without inducing mutations. The presented results also indicate that Pol V may provide substrates for MFD repair; moreover, we suggest that only those DNA lesions which result from umuDC-directed UV mutagenesis are subject to MFD repair.

10

Bakteriobójcza aktywność surowicy kręgowców ze szczególnym uwzględnieniem litycznej aktywności wobec pozajelitowych szczepów E. coli

71%

Sztucki D.

Laboratorium Medyczne

|

2018

|

tom nr 3

46--49

PL

Bakterie E. coli prezentują w swojej budowie struktury, które umożliwiają im unikanie odpowiedzi immunologicznej, a także przenikanie do krwi, a nawet pokonanie bariery krew/mózg. Z tego powodu są niezwykle niebezpieczne, a badania z wykorzystaniem modelu surowicy mogą dostarczyć informacji odnośnie stopnia patogenności analizowanych szczepów.

11

The number of E. coli and C. perfringens bacteria in poultry waste and subsequent phases of composting

63%

Cybulska K. , Suchecka N. , Wrońska I. , Mahdi-Oraibi S.

Proceedings of ECOpole

|

2015

|

tom Vol. 9, No. 1

19--24

EN

Rapidly growing commercial poultry production generates large amounts of waste. Waste that accumulates during the poultry slaughter process often remains unprocessed, becoming a serious threat to people’s health and the natural environment. Poultry production waste constitutes problems odour threat and dangerous sanitary threat. The aim of this study was to determine the population size of Escherichia coli and Clostridium perfringens in poultry waste and in successive stages of waste composting. Research material consisted of raw feathers collected immediately after the slaughter, samples of biological sludge from the centrifuge, mixture of straw, feathers and lime and processed compost. Microbiological analyses were conducted with the use of spread plate count method and the substrate was used in accordance with research standards. The size of population of microorganisms in the samples analyzed corresponded to the waste processing stage and group of microbes. The presence of C. perfringens strains was ascertained in all samples, whereas E. coli strains were identified only in raw feathers and centrifuge sludge, being most numerous in unprocessed material. A reverse trend was observed in case of C. perfringens with the highest population density in centrifuge sludge and least density in raw feathers.

PL

Intensywnie rozwijająca się produkcja drobiarska wiąże się z generowaniem dużej ilości odpadów. Powstające produkty uboczne podczas uboju pozostawione w stanie surowym stają się poważnym zagrożeniem dla środowiska naturalnego i zdrowia ludzi. Mogą stwarzać problemy odorotwórcze oraz istotnie groźne zanieczyszczenie sanitarne. Celem przeprowadzonych badań było określenie liczebności E. coli i C. perfringens w odpadach drobiarskich oraz kolejnych etapach ich kompostowania. Materiał badawczy stanowiły świeże pióra bezpośrednio po uboju, osad biologiczny z wirówki, mieszanina słomy, pierza i wapna oraz kompost przerobiony. Analizy mikrobiologiczne wykonano metodą płytkową, wykorzystując wybiórcze podłoża zgodne z normami. Liczebność mikroorganizmów w badanych próbach zależała od fazy przerobu odpadu i analizowanej grupy drobnoustrojów. Obecność bakterii C. perfringens stwierdzono we wszystkich próbach, natomiast bakterie E. coli tylko w piórach surowych i osadzie z wirówki, przy czym najliczniej występowały w materiale nieprzetworzonym. Odwrotną tendencję zaobserwowano w przypadku C. perfringens, które najliczniej zasiedlały osad z wirówki, natomiast ich mniejszą liczebność stwierdzono w piórach surowych.

12

System Colilert - postęp w analizie jakości mikrobiologicznej wody

63%

Otlewska A. , Dybka K. , Kręgiel D.

Przemysł Spożywczy

|

2013

|

tom T. 67, nr 3

18-22

PL

Alternatywne metody badania stanu mikrobiologicznego wody oparte na technologii zdefiniowanych substratów stanowią doskonałe uzupełnienie metod referencyjnych, dostarczając istotnych informacji w krótkim czasie i umożliwiając podjęcie działania w sytuacjach krytycznych. W artykule opisano system Colilert-18/Quanti-Tray 2000 stanowiący przykład zastosowania technologii zdefiniowanych substratów, umożliwiający równoczesną detekcję bakterii grupy coli i E. coli bezpośrednio w badanej próbie wody. Wchodzące w skład pożywki substraty ONPG (chromogenny o-nitrofenylo-β-D-galaktopiranozyd) i MUG (fluorogenny 4-metyloumbeliferylo-β-D-glukuronid) są metabolizowane przez enzymy bakterii grupy coli i E. coli obecne w badanej próbie wody, w wyniku czego uwalniany jest żółty (β-D-galaktozydaza) lub fluoryzujący (β-D-glukuronidaza) produkt. Wysoka specyficzność enzymów, zastosowanych w omawianym systemie wyeliminowała konieczność wykonywania testów potwierdzających.

EN

Alternative methods employed in microbiological analysis of water quality, based on defined substrate technology, are the excellent supplementation of reference methods, providing essential information in a short time and enabling action in critical situations. This paper describes the Colilert-18/Quanti-Tray 2000 system, being commercial application of defined substrate technology, which ensures simultaneous detection of total coliforms and E. coli directly in the water samples. Substrates ONPG and MUG included in the media are metabolized by enzymes of coliforms (β-galactosiadase) and/or E. coli (β-glucuronidase) present in the sample, resulting in the release of a yellow or fluorescent product, respectively. The high specificity of the enzymes used in this system has eliminated the need for confirmatory testing.

13

Escherichia coli in sewage sludge - detection method

63%

Machnicka A.

Chemistry-Didactics-Ecology-Metrology

|

2014

|

tom R. 19, NR 1-2

79--85

EN

Escherichia coli is Gram-negative optionally anaerobic roads which belongs to Enterobacteriaceae family. Includes in a physiological bacterial flora of human and warm-blooded animals large intestine. Escherichia coli is being met in abiotic elements of the environment so as waters, wastewater, sewage sludge, soil and the food. This bacterium is showing the pathogenicity in named terms for the peoples, triggering diseases mainly: gastrointestinal tract and urinary. Quality and quantitative proposed detections method of the bacteria E. coli contains five/six steps: - appointment dry suspended solid, - preparation averaged, test of sample and resuscitation of bacteria, - making dilutions, - enrichment and differentiation in chromogenic-selective medium, - enumerating the amount of cfu E. coli in 1 g of a dry weight, - optionally, the biochemical identification.

PL

Escherichia coli jest Gram-negatywną, względnie beztlenową pałeczką należącą do rodziny Enterobacteriaceae. Wchodzi w skład fizjologicznej flory bakteryjnej jelita grubego człowieka oraz zwierząt stałocieplnych. Spotyka się ją w elementach abiotycznych środowiska, takich jak wody, ścieki, osady ściekowe, gleba i żywność. Bakteria ta w określonych warunkach wykazuje chorobotwórczość dla człowieka, wywołując głównie schorzenia układów pokarmowego i moczowego. Proponowana metoda jakościowa i ilościowa wykrywania bakterii E. coli zawiera pięć/sześć etapów: - oznaczenie suchej masy osadu, - przygotowanie próbki uśrednionej i badawczej oraz przywrócenie bakteriom aktywności fizjologicznej, - wykonanie rozcieńczeń, - namnażanie i identyfikacja na podłożu chromogennym-selektywnym, - wyliczenie ilości jtk E. coli w 1 g suchej masy osadu, - opcjonalnie identyfikacja biochemiczna.

14

Sanitary evaluation of the water from water intake points situated in Gorzow Wielkopolski and neighbouring localities

63%

Wrońska I. , Cybulska K.

Ecological Chemistry and Engineering. A

|

2015

|

tom Vol. 22, nr 1

17--26

EN

Water is an essential component necessary for sustaining life. Nevertheless, it may pose a serious threat to human life resulting from possible occurrence of pathogenic and potentially pathogenic microorganisms. Therefore, monitoring and continuous microbial surveillance of the water intended for consumption is extremely important. The requirements referring to qualitative parameters which should be met by water are set out in the Regulation of the Minister of Health of 29 March 2007, as amended on 20 April 2010, and the EU directives. The quality of water being supplied to consumers depends on many factors, among other on the type of water intake (surface water or groundwater), efficiency of water treatment and disinfection, and technical condition of the water supply network. The analysis of the sanitary condition of drinking water has been conducted form water intakes in the city of Gorzow Wielkopolski, ie Centralny Kosynierow Gdynskich intake, Klodawa intake and Siedlice intake, and in neighbouring localities, ie. Maszewo and Marwice. The research material was raw and treated water samples. The population size of Faecal streptococci, coliform bacteria, including E. coli, and total mesophilic and psychrophilic bacteria counts was determined. The analysis of the sanitary condition of drinking water has been conducted. The number of coliform bacteria, including E. coli, and streptococci was determined by the method of membrane filters, whereas total mesophilic and psychrophilic bacteria counts using the plate method under incubation conditions conforming to the standards. The presence of mesophilic and psychrophilic bacteria was observed in all examined water intake points. Differences in their counts over the whole year being significant. In three research points, ie Centralny Kosynierow Gdynskich intake, Maszewo intake and Marwice intake, psychrophilic bacteria count was exceeded (100 CFU ۰ cm–3). In the case of pathogenic bacteria, their occurrence was occasionally observed in the drinking water intake points. The water treatment processes applied and, as the final result, water sanitary assessment according to the existing standards and the provision stipulated allow it to be collected for consumption purposes and do not pose the threat to human health and life.

PL

Woda jest podstawowym składnikiem niezbędnym do utrzymania życia. Jednakże, może ona stworzyć poważne zagrożenie dla zdrowia człowieka wynikające z możliwości wystąpienia mikroorganizmów chorobotwórczych i potencjalnie chorobotwórczych. W związku z tym, niezwykle istotna jest kontrola oraz stały nadzór mikrobiologiczny nad wodą przeznaczoną do spożycia. Wytyczne co do parametrów jakościowych, jakim powinna odpowiadać, zawarte są w Rozporządzeniu Ministra Zdrowia z dnia 29 marca 2007 r. wraz ze zmianą z dnia 20 kwietnia 2010 r. oraz Dyrektywach Unii Europejskiej. Jakość wody dostarczanej konsumentom zależy od wielu czynników m.in.: rodzaju ujęcia (woda powierzchniowa lub podziemna), skuteczności procesów uzdatniania i dezynfekcji oraz stanu technicznego sieci wodociągowej. Przeprowadzono analizę stanu sanitarnego wody pitnej pochodzącej z ujęć wodnych zaopatrujących miasto Gorzów Wielkopolski, tj. ujęcie Centralne Kosynierów Gdyńskich, Kłodawa, Siedlice oraz sąsiadujące miejscowości, tj. Maszewo i Marwice. Materiałem badawczym były próbki wody surowej i uzdatnionej. Określono liczebność paciorkowców kałowych, bakterii z grupy coli, w tym E. coli oraz ogólnej liczebności bakterii mezofilnych i psychrofilnych. Liczebność bakterii z grupy coli, w tym E. coli oraz paciorkowców kałowych oznaczono metodą filtrów membranowych, zaś ogólną liczebność bakterii mezofilnych i psychrofilnych metodą płytkową w warunkach inkubacji zgodnych z normami. We wszystkich badanych punktach stwierdzono obecność bakterii mezofilnych i psychrofilnych. Różnice w ich liczebności na przestrzeni całego roku były istotne. W punktach badawczych, tj. Centralne Kosynierów Gdyńskich, Maszewo oraz Marwice odnotowano przekroczenie norm ilości psychrofilii 100 j.t.k. ۰ cm–3. Obecność bakterii chorobotwórczych w badanych próbkach wody pitnej wykryto sporadycznie. Zastosowane procesy uzdatniania i w efekcie końcowym ocena sanitarna wody według obowiązujących norm i zawartej klauzuli pozwalają na jej pobór do spożycia i nie stanowią zagrożenia dla zdrowia i życia ludzi.

15

Assessment of possibilities of spreading of bioaerosol from different technological objects in small sewage treatment plants

62%

Zabłocka-Godlewska E. , Przystaś W. , Żak M.

Architecture Civil Engineering Environment

|

2022

|

tom Vol. 15, no. 2

177--186

EN

The Covid-19 pandemia increased the attention of the world community to air biocontamination. Sewage treatment plants (STPs) generate a bioaerosol during different technological operations. Research aimed to estimate the range of bioaerosol emission from different technological objects of 5 small STPs. Such knowledge is very important for risk assessment, monitoring programs and pollution limitation. The sedimentation method was used for the detection of mesophiles, psychrophiles, Escherichia coli, pigmented bacteria, Streptococcus faecalis, Pseudomonas fluorescens, and mold fungi. The highest level of psychrophiles and mold fungi (> 1000 cfu/m3) was detected in points located near activated sludge chambers, sludge thickening tanks, and secondary clarifiers. The mesophiles (>500 cfu/m3) and E. coli aren’t a normal component of air microflora, but were detected in all measurement points, especially near a pomp station (inflow), grit, activated sludge, sludge thickening chambers. At the points located at the leeward, the number of microorganisms was higher than in the windward. The research results indicate the necessity of constant monitoring of the STP impact on the air quality.

16

Antibiotic Susceptibility Test of Bacteria Isolated From Fruit Juices Sold in Cafes and Restaurants of Debre-Markos Town, North Western Ethiopia

51%

Geta K. , Kebede A. , Chemedissa M.

World News of Natural Sciences

|

2019

|

tom 24

365-371

EN

The prevalence of antimicrobial resistance among food pathogens has increased during recent decades. In this work, pathogenic bacteria such as Staphylococcus aureus, Salmonella spp., Shigella spp., and E. coli were isolated following standard methods. The bacterial isolates were then tested for their sensitivity to common antibiotics using the disc diffusion method on Mueller-Hinton Agar. All of the pathogenic bacteria were found to be resistant to erythromycin and almost all were sensitive to penicillin.

17

Wpływ dezynfekcji ścieków komunalnych ługiem sodowym na przeżywalność pałeczek E. coli i paciorkowców kałowych grupy D

51%

Paluszak Z. , Skowron K. , Gryń G. , Wiśniewska E. , Szkudlarek-Kowalczyk M. , Ziętara A.

Ekologia i Technika

|

2011

|

tom R. 19, nr 5

243-246

PL

Ścieki komunalne zawierają znaczne ilości drobnoustrojów, w rym także patogennych. W składzie mikroflory allochtonicznej tego środowiska dominują pałeczki E. coli oraz paciorkowce kałowe grupy D. Stanowią one bardzo dobry wskaźnik poziomu mikrobiologicznego zanieczyszczenia ścieków i skuteczności procesów ich oczyszczania. Celem przeprowadzonych badań było określenie skuteczności higienizacyjnego działania ługu sodowego na pałeczki E. coli oraz paciorkowce grupy D w ściekach komunalnych. W ramach eksperymentu określono przeżywalność pałeczek E. coli oraz paciorkowców kałowych grupy D w ściekach, w których końcowe stężenie NaOH ustalono na poziomie odpowiednio 0,25%, 0,5%, 1,0% i 1,5%. Liczba badanych bakterii była ustalana w oparciu o metodę NPL w układzie 3-probówkowym. Próbki do oznaczeń pobierano po 5, 15, 30, 60 i 360 minutach. Na podstawie badań dotyczących przeżywalności dwóch wybranych bakterii wskaźnikowych w ściekach komunalnych stwierdzono, że skuteczność higienizacyjna NaOH zależy od zastosowanego stężenia dezynfektantu oraz gatunku mikroorganizmów. We wszystkich badanych wariantach zdecydowanie krócej przeżywały pałeczki E. coli. Dodatek ługu sodowego wpłynął również na podwyższenie pH ścieków.

EN

Municipal sewage contains significant number of microorganisms, including pathogens. The composition of the allochtonous microflora in this environment is dominated by E. coli and faecal streptococci group D. These microorganisms are very good indicator of the level of microbial contamination of sewage and the effectiveness of its treatment. The aim of this study was determination of the hygienization effectiveness of sodium hydroxide against E. coli and streptococcus group D in municipal sewage. In the experiment the survival E. coli and faecal streptococci group D was determined in the sewage in which the final concentration of NaOH was found at the level of 0,25%, 0,5%, 1,0% and 1,5% respectively. The number of tested bacteria was determined based on the MPN method. The samples for determinations were taken after 5, 15, 30, 60 and 360 minutes. On the basis of the survival of two selected indicator bacteria in municipal sewage, it was found that the hygienization effectiveness of NaOH depends upon the concentration of disinfectant and germs species. In all tested variants the survival of E. coli was significantly shorter. Addition of caustic soda has also affected the increase in pH of the sewage.