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1

The impact of UV mediated hydrogen peroxide on culturable bacteria in the surface microlayer of eutrophic lake

100%
Walczak M., Swiontek Brzezinska M.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 3
547-554
Hydrogen peroxide (H₂O₂) formation in surface waters is initiated by the absorption of sunlight by dissolved organic matter (DOM). The fraction of the DOM pool that interacts with sunlight, referred to as chromophoric dissolved organic matter, impacts the optical properties of surface waters. Second source of H₂O₂ is wet and dry deposition of photogenerated substance in the atmosphere and biological production. The study examined the concentration of hydrogen peroxide in water from the surface microlayer (SM) (<100 m) and subsurface water (SSW) (25 cm) in the typical eutrophic (TOC 5–15 mg dm⁻³; chlorophyll 5–26 g dm⁻³, water transparency 0.6–1.0 m) lake as well as the impact of this compound on occurrence and survivorship of catalase-positive and catalase-negative bacteria isolated and cultured on the TSA medium (Difco). The experimental H₂O₂ concentrations ranged between 500–5000 nM. The concentration of H₂O₂ in analyzed water samples clearly increased in day-time hours and was different in May, July and October. The highest natural concentration of H₂O₂ (700 nM) was observed in SM water in summer in afternoon hours. During that period, 100% of bacterial populations found in SM water produced catalase. The experiments confirmed that environmental concentrations of H₂O₂ caused no considerable decrease in survivorship of culturable bacteria, while concentrations exceeding 1000 nM were lethal for the majority of catalasenegative bacteria, but not for catalase-positive bacteria.
2

Phylogenetic diversity and abundance of bacteria from surface microlayer and subsurface water in eutrophic lake

100%
Walczak M., Swiontek Brzezinska M.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
The bacteria from different phylogenetic groups were studied in surface microlayer (SM, up to 100 μm) versus subsurface water (SW – 20 cm) in eutrophic lake from spring to autumn of 2007. Abundance of bacteria was determined using a combination of direct counting of 4’, 6-diamidino-2-phenylindole and the phylogenetic diversity was determined in fluorescence in situ hybridization (FISH) method with group-specific, fluorescently labeled oligonucleotide probes. The numbers of DAPI bacteria varied between 4.75 and fluorescence in situ hybridization (FISH) demonstrated that Eubacteria constituted the majority of the whole bacterial population and their percentage share ranged from 59 to 75%. Abundances of alpha- beta-Proteobacteria and Cytophaga-Flavobacteria groups varied across seasons, layers, and lacustrine zones. The lowest number of alphaProteobacteria group bacteria was observed in spring (SM – 0.2 × 10⁶, SW – 0.16 × 10⁶ cells cm⁻³), whereas the highest in autumn (SM – 0.62 × 10⁶, SW – 1.6 × 10⁶ cells cm⁻³). The percentage share of these groups of bacteria in the Eubacteria domain was lower in spring (20–50%) than in summer and autumn (from 65 to over 80%). No fixed difference between the composition of SM and SW bacteria was noticed. Seasonally occurred changes are similar in both layers.
3

The utilization of N-acetyloglucosamine and chitin as sources of carbon and nitrogen by planktonic and benthic bacteria in Lake Jeziorak

100%
Donderski W., Swiontek Brzezinska M.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 6
It follows from the research conducted on the number of chitinolytic bacteria among planktonic and benthic bacteria that they occur in a higher number in bottom sediments than in water. However, the per­centage of chitinolytic bacteria among the total number of heterotrophic bacteria was higher in the water than in the bottom sediments. Chitinolytic bacteria and the bacteria unable to decompose chitin most readily utilized N-acetyloglucosamine as additional sources of carbon and nitrogen. Chitinolytic bacteria devel­oped well on a substrate with colloidal chitin as the only or an additional source of carbon and nitrogen. However, bacteria unable to decompose chitin displayed very weak growth on a substrate with colloidal chitin as the only source of carbon and nitrogen.
4

The influence of heavy metals on the activity of chitinases produced by planktonic, benthic and epiphytic bacteria

100%
Donderski W., Swiontek Brzezinska M.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 6
Research was carried out on the influence of heavy metals on the activity of chitinases produced by chitinolytic bacteria isolated from Moty Bay in Lake Jeziorak. In tests on the concentration of heavy metal ions in the surface water, the highest concentration of copper and zinc ions was found in July in the littoral zone, of cobalt ions in September in the pelagic zone and of lead ions in August, also in the pelagic zone. Studies on the number of chitinolytic bacteria have shown that the highest number of chitinolytic bacteria among the total number of heterotrophic bacteria occurred on macrophytes and in bottom sediments. The highest percentage of chitinolytic bacteria was found in the surface water, and the lowest in the bottom sediments. As follows from research on the influence of heavy metals on the activity of chitinases , in the majority of the strains tested, heavy metal ions inhibited chitinolytic activity as concentration increased.
5

Occurrence of chitinolytic bacteria in water and bottom sediment of eutrophic lakes in Ilawskie Lake District

100%
Donderski W., Swiontek Brzezinska M.
Polish Journal of Environmental Studies
|
2001
|
tom 10
|
nr 5
A study was carried out on the occurrence of chitinolytic bacteria inhabiting surface water, water above the sediment and bottom sediments of lakes: Jeziorak, Jeziorak Maly and Tynwald. The greatest amounts of them were found in demersal water and in bottom sediment surface stratum. However, the percentage share of chitinolytic bacteria proved greater in deep water (9.35%) than in bottom sediments (2.16%). Surface water and the part just over the sediment contained most chitinolytic bacteria in a heavily eutrophicated lake Jeziorak Maly located in a town (11.9% and 12.6% respectively), whereas they inhabited bottom sediments in large amounts in lake Jeziorak (2.9%). The most abundant among chitinolytic bacteria were the genera of: Achromobacter, Bacillus and family of Enterobacteriaceae.
6

The importance of the sand-reed filter in the domestic sewage treatment

81%
Lalke-Porczyk E., Swiontek Brzezinska M., Donderski W.
Polish Journal of Natural Sciences
|
2008
|
tom 23
|
nr 1
152-163
Research was carried out on the number of the heterotrophic bacteria capable of growth in the temperatures of 22°C (TVC 22°C) and 37°C (TVC 37°C) and the bacteria indicating the sanitary and bacteriological state: coliform bacteria (TC), fecal coliform bacteria (FC) and fecal streptococci (FS) in the process of domestic sewage cleaning on a reed overgrown plot in the communal sewage treatment plant at Wielka Nieszawka. It was ascertained that there followed a high reduction in the number of the bacteria from the investigated groups during the flow of the sewage through the sand-reed filter (by 60.6% to 89.3% on average), except for the fecal streptococci whose number decreased by 10.5% on average in the investigated period. Besides, it was demonstrated that the rhizomes of the common reed had made a convenient habitat for the development of the indicatory bacteria.
7
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Microbiological contamination of water in fountains located in the city of Torun, Poland

81%
Burkowska-But A., Swiontek Brzezinska M., Walczak M.
Annals of Agricultural and Environmental Medicine
|
2013
|
tom 20
|
nr 4
8

Microbial degradation of shrimp waste in soil

81%
Swiontek Brzezinska M., Lalke-Porczyk E., walczak M., Donderski W.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 3
627-633
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