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Microbial air contamination on the premises of the sewage treatment plant in Bydgoszcz (Poland) and antibiotic resistance of Staphylococcus spp.

Małecka-Adamowicz M., Kubera Ł., Donderski W., Kolet K.

Archives of Environmental Protection

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2017

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Vol. 43, no. 4

58--65

EN

The study was aimed at evaluating microbial contamination on the premises of the sewage treatment plant by determining the concentrations of selected groups of airborne microorganisms. Another objective was to determine the antibiotic sensitivity patterns of isolated strains of staphylococci. The research was conducted in a seasonal cycle, by the impaction method using Merck MAS-100 air sampler. Samples were collected at six sites, each representing a different stage of sewage treatment. The susceptibility of isolated staphylococci was assessed with the disc-diffusion method, following the recommendations of the EUCAST. The results indicate that the microbial population in the air of the investigated area was dominated by mold fungi, whose highest average concentration was recorded at site IV located near the final clarifier (7672 CFU•m-3). Heterotrophic bacteria and mannitol-positive staphylococci were the most numerous at locations where sewage undergoes primary treatment. In each subseuqent stage the number of microorganisms emitted into the air from the sewage was lower. Antibiograms show that more than 50% of Staphylococcus spp. exhibited resistance to penicillin and 20% to rifampicin. In addition, 90% of the analyzed strains were sensitive to other antibiotics. The fungal community included the following genera: Cladosporium, Fusarium, Alternaria, Penicillium, Aspergillus, Aureobasidium, and Acremonium.The highest air contamination with all studied groups of microorganisms was recorded at the locations where mechanical sewage treatment was performed. During the subsequent stages lower numbers of heterotrophic bacteria were emitted into the air. The air in the investigated sewage treatment plant did not contain multidrug-resistant staphylococci.

PL

Celem pracy była ocena stopnia mikrobiologicznego zanieczyszczenia powietrza na terenie oczyszczalni ścieków, określonego na podstawie liczebności wybranych grup drobnoustrojów oraz ocena wrażliwości wyizolowanych szczepów gronkowców na wybrane antybiotyki, co pozwoliło określić stopień ich antybiotykooporności. Badania przeprowadzono w cyklu sezonowym, przy użyciu metody zderzeniowej za pomocą próbnika MAS-100 Merck. Próbki pobierane były z 6 stanowisk badawczych zlokalizowanych w miejscach reprezentujących poszczególne etapy oczyszczania ścieków. Lekowrażliwość wyizolowanych gronkowców oceniano metodą dyfuzyjno-krążkową zgodnie z rekomendacjami EUCAST. Analizy wykazały, że wśród mikrobiota powietrza najliczniej występowały grzyby pleśniowe osiągając maksimum liczebności na stanowisku IV zlokalizowanym przy osadniku wtórnym radialnym (7672 CFU•m-3). Bakterie heterotroficzne i gronkowce mannitolododatnie najliczniej występowały w miejscach wstępnego etapu oczyszczania ścieków. Wraz z zaawansowaniem procesów oczyszczania, ścieki emitowały do powietrza atmosferycznego coraz mniejszą ilość mikroorganizmów. Na podstawie antybiogramów stwierdzono, że ponad 50% badanych szczepów Staphylococcus spp. wykazywała oporność wobec penicyliny i 20% wobec rifampicyny, natomiast 90% analizowanych szczepów było wrażliwych na pozostałe antybiotyki. Wśród grzybów pleśniowych w powietrzu na terenie oczyszczalni ścieków odnotowano grzyby z rodzaju: Cladosporium, Fusarium, Alternaria, Penicillium, Aspergillus, Aureobasidium i Acremonium. Największym zanieczyszczeniem powietrza, w przypadku wszystkich badanych grup mikroorganizmów, charakteryzowały się stanowiska zlokalizowane w miejscach odpowiedzialnych za część mechaniczną procesu oczyszczania ścieków. Wraz z zaawansowaniem procesów oczyszczania, ścieki emitowały do powietrza atmosferycznego coraz mniejszą ilość bakterii heterotroficznych. Na terenie oczyszczalni ścieków nie stwierdzono rozprzestrzeniania się szczepów gronkowców wielolekoopornych.

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Rola oczyszczalni hydrobotanicznych w oczyszczaniu ścieków z terenów wiejskich

Lalke-Porczyk E., Swiontek Brzezinska M., Donderski W.

Woda-Środowisko-Obszary Wiejskie

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2010

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T. 10, z. 3

119-127

PL

Celem badań była ocena skuteczności oczyszczania ścieków bytowo-gospodarczych w małej przydomowej oczyszczalni wierzbowej oraz doczyszczania ścieków w gminnej, mechaniczno-biologicznej oczyszczalni z filtrem piaskowo-trzcinowym. Próbki ścieków do badań pobierano w okresie od maja do grudnia 2007 r. Liczebność bakterii heterotroficznych zdolnych do wzrostu w temperaturze 22°C (jtk 22°C) i 37°C (jtk 37°C) oznaczano metodą płytek lanych zgodnie z normą PN-ISO 6222. Liczebność bakterii z grupy coli (TC) oraz bakterii termotolerancyjnych (fekalnych) z grupy coli (FC) oznaczano metodą fermentacyjną probówkową zgodnie z PN-75/C-04615/05 i PN-77/C-04615/07. Liczebność paciorkowców kałowych [FS] badano metodą filtrów membranowych zgodnie z PN-82/C-04615/25 na podłożu Slanetza-Bertleya. Wykazano znaczne zmniejszenie liczebności większości badanych grup bakterii w trakcie oczyszczania ścieków metodą hydrobotaniczną. W najmniejszym stopniu zmniejszyła się liczebność paciorkowców kałowych.

EN

One of the ways to solve the sewage treatment problems in Polish rural areas is the use of unconventional sewage treatment systems based on ponds with macrophytes or on ground filters with hydrophytes. Their function follows the model of natural wetlands. They are featured by many merits and can be used to treat sewage from single farms, small villages, land estates or agro-tourist centres. Beside abiotic processes such as sedimentation and filtration, sorption of chemical pollutants in the medium and photolytic reactions, an important role in sewage treatment play biological factors - vascular flora and microorganisms in a given object. The aim of this study was to assess the effect of sewage treatment in a small home willow treatment plant and treated sewage polishing in the communal mechanical-biological treatment plant with sand-reed filter. The sewage for analyses was sampled from May to December 2007. The number of heterotrophic bacteria capable of growing at temperatures of 22°C (cfu 22°C) and 37°C (cfu 37°C) was estimated by cast plate method according to Polish standard PN-ISO 6222. The numbers of coliform bacteria [TC] and thermo-tolerant (faecal) coliform bacteria [FC] were estimated by means of fermentation test-tube method according to Polish standards PN-75/C-04615/05 and PN-77/C-04615/07. The number of faecal streptococci (FS) was determined by the membrane filter method according to Polish standard PN-82/C-04615/25 with the use of Slanetz-Bertley medium. Considerable reduction of the majority of investigated bacteria groups was found during hydrophyte sewage treatment. The lowest reduction was observed in the number of faecal streptococci.

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The impact of UV radiation on metabolism of neustonic and planktonic bacteria in eutrophic lake

Burkowska A., Walczak M., Donderski W.

Polish Journal of Ecology

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2010

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Vol. 58, nr 2

211-219

EN

The range of solar radiation reaching the air-water inter-phase, medium wave UV radiation, i.e. UVB 290-320 nm and UVA 320-400 nm, is of the highest biological importance due to its harmful effects. Radiation within this range causes DNA damage (lethal effect) or limits the growth of organisms by inhibiting enzyme synthesis, reducing active transport, or by inducing mutations. The studies were carried out in 2007 based on samples water collected from surface microlayer (SM) (up to 150 [mu]m) and subsurface water (SSW) (25 cm) of pelagic zone of eutrophic lake. The representative collection of bacterial strains was isolated from collected samples. The following are measured: the DNA and cellular protein synthesis activity, respiration activity of the bacteria and activity of hydrolytic enzymes in control cultures, subjected to UVB radiation (applied dose 100 mW cm[^-2]) and with and without humic substances (HS) (final concentration 100 mg L[^-1]) playing role of compounds potentially protective from UV radiation. UVB irradiation had the strongest inhibiting impact on production of DNA in bacterial cells (12-23% of that in non-irradiated samples). UVB radiation also inhibits the synthesis of cellular protein (27-43% of that in non-irradiated samples) and bacterial respiration activity (44-48%). UVB radiation had by far the lowest impact on the activity of hydrolytic enzymes. HS may function as a protective agent against UV radiation only in DNA synthesis. No significant differences in response to UVB were found between planktonic and neustonic bacteria.

4

Degradation of chitin in natural environment : role of Actinomycetes

Swiontek Brzezinska M., Lalke-Porczyk E., Donderski W., Walczak M.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

229-238

EN

The actinomycetes in water samples and bottom sediments of lowland, eutrophic lake as well as in soil (farmland, sandy) of the lake basin were studied. Chitin-degrading actinomycetes were isolated (with a plate technique) from each habitat; subsequently, their chitinolytic activity (with the fluorometric method) was determined in relation to temperature (10-50[degree]C) and the physical type of chitinous substance (colloidal chitin, chitin powder, and shrimp shells). This study demonstrated that actinomycetes were the most abundant in soil samples (average of 18x10[^3] CFU g[^-1] in farmland soil, 9x10[^3] CFU g[^-1] in sandy soil), and the least abundant in water samples (average of 2.7x10[^1] CFU mL[^-1] in lake water at neutral pH, 0.6x10[^1] CFU mL[^-1] in lake water with alkaline pH). The highest percentage of chitinolytic actinomycetes was observed in soil (average of 80% in sandy soil and 85% in farmland soil). Chitinolytic actinomycetes also made up a large fraction of total actinomycetes in water samples (average of 73%). In silt and sandy sediments, percentages of chitinolytic actinomycetes equaled 23 and 15%, respectively. Actinomycetes collected in soil were characterized by the highest activity (average of 14 nmol MUF mg[^-1] of protein h[^-1] in farmland soil, 8.5 nmol MUF mg[^-1] protein h[^-1] in sandy soil). The lowest activity was observed among benthic actinomycetes (average of 5.4 nmol MUF mg[^-1] of protein h[^-1] in silt, 0.65 nmol MUF mg[^-1] protein h[^-1] in sandy sediments). The impact of temperature and the type of chitinous substrate on the activity of chitinases produced by actinomycetes demonstrated that their activity peaked at 40[degree]C and in the presence of colloidal chitin. Observed differences in actinomycetales number and activity in the lake and the soil may be explained by higher accumulation of chitin substances in the soil. This polymer allows microorganisms to continually synthesize chitinolytic enzymes and take active part in that compound decomposition.

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The role of chitinolytic bacteria and fungi in biodegradation of crustacean remains in lacustrine habitats

Swiontek Brzezinska M., Lalke-Porczyk E., Donderski W.

Polish Journal of Ecology

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2008

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Vol. 56, nr 2

335-342

EN

This study presents results of research on occurrence of chitinolytic bacteria and fungi in water, bottom sediments, and watershed soil of an eutrophic lake and on their ability to use the crustacean skeletons (shrimp waste) as a respiration substrate. It was found that the respiration rate of bacteria and fungi during decomposition of chitin varied in different environments. The participation of chitinolytic microorganisms in water (13%) and soil (18%) was greater than in bottom sediments (5%). The respiration activity in the presence of all parts of shrimp waste and shrimp exoskeletons observed in chitinolytic bacteria was higher than that of fungi. But fungi demonstrated the highest metabolic activity in the presence of the shrimp head sections. The highest respiration activity was observed in planktonic and soil bacteria, while the lowest, in benthic strains. The chitinolytic bacteria used well all examined respiration substrates (all parts of shrimp waste - 671 mg O[2] g[^-1] protein in 5 days, the shrimp head sections - 851 mg O[2] g[^-1] protein in 5 days and shrimp exoskeletons - 490 mg O[2] g[^-1] protein in 5 days). No significant differences in respiration activity were observed in chitinolytic fungi isolated from water, bottom sediments and soil. All of fungal strains demonstrated the highest metabolic activity in the presence of the shrimp head sections (average 1083 mg O[2] g[^-1] protein in 5 days). Shrimp exoskeletons were oxidized the least efficiently (average 160 mg O[2] g[^-1] protein in 5 days). Certain strains were not using them at all.

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Chitinolytic activity of bacteria and fungi isolated from shrimp exoskeletons

Swiontek-Brzezinska M., Lalke-Porczyk E., Donderski W.

Oceanological and Hydrobiological Studies

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2007

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Vol. 36, No.3

101-111

EN

Microbiological analysis of shrimp exoskeletons demonstrated considerable differences in abundance of heterotrophic bacteria and fungi. The number of heterotrophic bacteria was greater by two orders of magnitude than that of fungi. The survey, however, did not reveal significant differences in abundances of bacteria and fungi in samples coWected during different months of the survey. The percent contribution of chitinolytic fungi in shrimp exoskeletons was greater than that of bacteria that hydrolyze chitin. The activity of chitinase bacteria was always higher than fungi. Chitinases produced by bacteria demonstrated the highest level of activity at 40°C and pH = 8. In contrast, fungal chitinases showed the highest activity at 50°C and pH = 5.

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Ograniczenie rozwoju bakterii nitkowatych w osadzie czynnym

Walczak M., Donderski W., Pawluk H.

Wodociągi - Kanalizacja

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2005

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nr 4

10-12

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Neustonic versus planktonic bacteria in eutrophic lake

Kalwasińska A., Donderski W.

Polish Journal of Ecology

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2005

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Vol. 53, nr 4

571-577

EN

This paper presents the results of research on the number, the rate of secondary production and physiological properties of neustonic (surface microlayer SM ≈ 250 μm) and planktonic (subsurface water SSW ≈ 10-15cm) bacteria of the eutrophic lake (TP 30-99 μg l-1; TN 0.94-1.76 mg l-1; chlorophyll a 26.4-56.9 mg l-1; water transparency 1.2-1.9 m). It was found that the total number of neustonic bacteria (TNB) varied from 1.28 × 106 to 1.98 × 106 cells ml-1 and was from 1.4 to 2.0 times higher than the number of planktonic bacteria (P <0.001). TNB range for planktonic bacteria oscillated between 0.75 × 106 and 1.45 × 106 cells ml-1. The number of heterotrophic neustonic (SM) bacteria (CFU 22°C) was also higher by 2.0 to 13.3 times (P <0.001) being between 1.48 and 12.5 × 103 cells ml-1 while the CFU of bacteria in the SSW oscillated between 0.35 to 0.94 × 103 cells ml-1. Both the values of TNB and CFU displayed a distinct seasonal variation (P <0.001). However, the rate of secondary production of planktonic bacteria was higher (from 1.1 to 6.0 times) than the rate of production of neustonic bacteria (P <0.05) and displayed seasonal variability (P <0.001). The rate of secondary production in subsurface water ranged from 0.676 to 1.265 μgC l-1 h-1 while in surface microlayer from 0.118 to 0.597 μgC l-1 h-1. In neuston the bacteria decomposing fat and DNA were more common than in plankton (P <0.05).

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Effect of some heavy metals on neustonic and planktonic bacteria isolated from the Deep of Gdańsk

Mudryk Z., Donderski W., Skórczewski P., Walczak M.

Oceanological Studies

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2000

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Vol. 29, No. 1

89-99

EN

The effect of different concentrations of heavy metal ions Hg+2, Cd+2, Zn+2, Cu+2 on growth and respiratory activity of neustonic and planktonic bacteria derived from the Deep of Gdańsk was studied. The laboratory experiments demonstrated that all heavy metals examined exhibited toxic effects on the development and oxygen uptake by neustonic and planktonic bacteria. This effect depended on the kind of the metal and its concentration.