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The aim of the study was to evaluate the effect of mineral-organic mixture on changes in the abundance of selected soil microorganisms. The experiment contained: soil with NPK (nitrogen, potassium, phosphorus) + 3 % or 6 % lignite (MF+CW3 %, MF+CW6 %) and 3 % zeolite-carbon composite (NaX-C); soil with NPK + 3 % or 6 % leonardite (MF+CL3 %, MF+CL6 %) and 3 % NaX-C; soil without fertilisation (C); soil fertilised with mineral NPK fertilisers (MF). Plants participating in the experiment were spring wheat and spring oilseed rape. The presence of the selected microorganisms was determined: Azotobacter spp., actinomycetes, ammonifiers, bacteria and mold fungi. Using Koch’s serial dilution method, the abundance of selected soil microorganisms was performed. The conducted research allows to conclude that the abundance of detected microorganisms depended on both the applied fertilisation and the plant grown. For the spring oilseed rape, the highest abundance of microorganisms was determined in treatments where fertilisation with lignite mixtures was applied, while for spring wheat, with leonardite mixtures. Increasing (from 3 % to 6 %) the share of lignite and leonardite in fertiliser mixtures did not translate into a proportional growth in the abundance of microorganisms, so such a treatment has no economic justification. Given their alkaline pH, the mixtures used can be a substitute for calcium fertilisers to improve soil properties and, consequently, protect soil organic matter from degradation.

Given the growing interest among residents of large agglomerations in inhalation treatments in urban graduation towers, as well as the lack of research on the microbiological safety of brine, an attempt was made to provide new and unique information on the potential epidemiological risks that may occur in such places. The study covered one of Krakow’s brine graduation towers, opened in 2020, attracting crowds of city residents and tourists every spring/summer season. Based on a two-year microbiological study of brine, which included analysis of the presence of mesophilic and psychrophilic bacteria in it, as well as indicators of microbiological water quality, i.e., Escherichia coli, Enterococcus faecalis, Clostridium perfringens, Staphylococcus spp., and Salmonella spp., it was concluded that contamination increased periodically. According to standards for inhalation waters, acceptable counts of selected microorganisms were exceeded, especially during the holiday season. It was, undoubtedly, related to weather conditions conducive to outdoor inhalation treatments, and thus the large number of heath resort visitors present near the graduation tower. Despite the fact that our study provides epidemiologically disturbing results, it is extremely valuable because it constitutes a starting point for discussion of the health safety of urban graduation towers. The study is also an opportunity to take measures to improve the microbiological quality of the brine in the closed cycle of graduation towers.

Hot trub (HT) from the brewing process is treated as waste or a by-product. Although several methods are known for managing this material, its processing is still problematic. Therefore, a study was conducted to evaluate the use of refuse-derived fuels (RDF) and undersized fraction from municipal solid waste (UFMSW) as bulking agents for HT biodrying. The analyses were aimed at determining whether it is possible to obtain a solid fuel (after two weeks of biodrying) with beneficial energy properties and stable in terms of microbiological risks. The study assessed the effects of bulking agents and air-flow rates on the biodrying index (BI), changes in the energy properties of the mixtures used and the number of microorganisms. Results showed that HT subjected to biodrying with the addition of RDF (in a 3:7 ratio) allowed to obtain the BI of 9.85, with 41% water removal, insignificant organic matter loss (5.5%), and a significant increase (>30%) in the lower heating value. It was an effect of low bulk density and high air-filled porosity in trials with RDF, resulted in better water drainage. Biodrying also reduced or completely eliminated certain pathogens; therefore, this finding suggests using RDF as the main component in HT biodrying.

New ways of managing hop sediments from brewing and fermentation of beer are constantly being sought and the existing ones improved as part of the circular economy. These wastes are not generated in large amounts, but the absence of their proper characteristics may lead to further processing errors. The study analyses the composting of hop waste under laboratory conditions and the effects of the biological activity of composts introduced into the soil. The study was carried out on two-hop sediments from two different technological stages of beer production: hot trub (HT) and spent hops (SH). Chemical, microbiological and biochemical analyses, as well as the assessment of phytotoxicity to Lepidium sativum L., were performed in the materials. The results proved that, due to their formation technology, the tested feedstocks are safe from an epidemiological point of view and are not a source of microbial contamination. Inhibitory properties for plant development were found for HT and it most likely results from the organic compound content. The mineral composition of hot trub does not exclude composting if its share in biomass is low. Spent hops (SH) were characterised by a significant total nitrogen content, which affected the composting process. Composting this sediment required the selection of substrates with a wide C:N ratio. The number of microorganisms inhabiting the analysed material was very diverse and varied depending on the type of sediments. The sample that contained the composted SH from dry hopping had a much larger number of microorganisms than the sample with HT from wet hopping.

The problem of cleaning and disinfecting surfaces has become extremely important in the context of the ongoing SARS-CoV-2 coronavirus pandemic. However, it should be considered that, in everyday life, we come into contact with many other viruses, as well as pathogenic bacteria and fungi, that may cause infections and diseases. Hence, there is a continuous need to search for new and more effective methods of fighting pathogens. Due to their documented antimicrobial activity, silver nanoparticles may be an interesting alternative to the commonly used surface cleaners and disinfectants. Therefore, the present study aimed to evaluate the bactericidal properties of silver nanoparticles obtained with the use of nontoxic plant waste biomass against bacteria isolated from the environment. Silver nanoparticles with the desired physicochemical characteristics were obtained by a simple and rapid chemical reduction method using plant waste such as unused parsley stems and potato peels (the biogenic method). A nanosilver colloid was also prepared by the chemical reduction method, but with reducing and stabilizing chemical substances (the chemical method) used as a control. The bacterial susceptibility to nanosilver synthesized using both methods was evaluated using the disk-diffusion method. The sensitivity of particular Escherichia coli and Staphylococcus aureus isolates to nanosilver varied considerably, and the strongest antimicrobial effect was found in the case of nanoparticles synthesized by the chemical method using a strong chemical reducing agent and a polymeric stabilizing substance, while nanosilver obtained using the biogenic method, using phytochemicals, also had a strong antimicrobial effect, which was found to be extremely satisfactory. Thus, it can be strongly concluded that the biogenic, pro-ecological method of synthesis with the use of plant waste biomass presented in this work allows the application of biogenic nanosilver as a component of agents for washing and disinfection of public utility surfaces.

Biochar improves soil physical, chemical and biological properties. However, there is a very limited number of studies comparing the effect of various doses of biochar and wheat straw with nutrients on microbiocenotic composition of soil and their connection with selected biochemical and chemical parameters of soil. The aim of this study was to determine the effect of the addition to the soil of wheat straw (WS) and wheat straw biochar (WSB) (300 °C) at 0.2%, 0.5%, 1%, and 2% doses and the addition of nutrients (MF) on microbial community composition (bacteria, fungi, actinobacteria, Azotobacter spp., ammonifiers, nitrifiers, denitrifiers, C. pasteurianum), dehydrogenase activity index, carbon and nitrogen fractions contents and the content of water soluble Cu, Cd, Zn, and Pb. It was demonstrated that coapplication of WS and WSB with MF at 1% and 2% doses increased carbon and nitrogen contents in soil and, in particular, their water soluble fractions (DOC and DON). The synergistic effect of biochar and MF contributed to the increase in the population of soil microorganisms. Dehydrogenase activity index in treatments with the addition of WS, WSB and MF was 1.6–4 times higher compared to the control. The content of heavy metals significantly (p ≤ 0.05) affected dehydrogenase activity and the number of nitrifiers and ammonifiers. It was demonstrated that the content of C and N measured for soil microbial biomass in treatments amended with biochar and MF was much greater than in control treatment and MF. However, our studies suggest that the microorganisms’ response to the addition of biochar with nutrients increased the number and intensified the activity of soil microorganisms.

The availability and affordability of fertilizers are the main risks currently faced by the fertilizer market. Therefore, there is a need to look for other sources of nutrient supply for plants, while taking care of soil properties. The application of fertilizers with the addition of functionalized materials could help in the efficient use of nutrients. The aim of the study was to assess the impact of the application of mixtures with the addition of zeolite–vermiculite composites (NaX–Ver) on the culturable microorganisms and selected soil properties. A two-year pot experiment was conducted on soil with elevated contents of cadmium, zinc, and lead. The test treatments included soil mixed with NPK and additives in two doses of NaX–Ver combined with leonardite (Leo) or lignite (L). The test plant used in the experiment was maize. The soil material was analyzed for the number of bacteria, mold fungi, actinomycetes, and ammonifiers. Furthermore, soil pH, EC, N total, and SOC contents, as well as soil respiration activity, were tested. The applied fertilizer mixtures had a great effect on changes in the N total and SOC contents. The N total increase was 45.5% in NaX–Ver3%L3% and 51% in NaX–Ver9%Leo6%, and the largest SOC increase (24.3%) was recorded in the NaX–Ver3%Leo3% treatment. The highest respiration activity was determined in NaX–Ver3%Leo3% and NaX–Ver9%Leo6%: 2.12 µg C-CO2 g−1 DM h−1 and 2.14 µg C-CO2 g−1 DM h−1, respectively. A significant correlation between pH values and the number of culturable microorganisms was found. The number of soil microorganisms depended on the type of fertilization used. The best stimulation of the number of culturable soil microorganisms was found in treatments with the addition of 3% of L or Leo in combination with NaX–Ver. The percentage increases in the number of the analyzed culturable microorganisms after the application of leonardite-based fertilization in combination with the zeolite–vermiculite composite were, on average: bacteria, 1096%; mold fungi, 1529%; actinomycetes, 1477%; ammonifiers, 910%.

During the production of beer, and especially beer wort, the main wastes are spent grain and hot trub, i.e., the so-called &ldquo, hot break.&rdquo, Combined with yeast after fermentation, they represent the most valuable wastes. Hot trub is also one of the most valuable by-products. Studies on the chemical composition of these sediments and their rheological properties as waste products will contribute to their effective disposal and even further use as valuable pharmaceutical and cosmetic raw materials. So far, hot trub has been studied for morphology and particle distribution depending on the raw material composition and beer wort extract. However, there are no preliminary studies on the rheological properties of hot trub and hops. In particular, no attention has yet been paid to the dependence of these properties on the hop variety or different protein sources used. The aim of this study was to examine the effect of different hopping methods on hot trub viscosity and beer wort physicochemical parameters. Additionally, the hop solutions were measured at different temperatures. A microbiological analysis of hop sediments was also performed to determine the post-process survival of selected microorganisms in these wastes. For manufacturers of pumps used in the brewing industry, the most convenient material is that of the lowest viscosity. Low viscosity hot trub can be removed at lower velocities, which reduces costs and simplifies washing and transport. The sediments also had similar equilibrium viscosity values at high shear rates.

Sterilization of municipal waste for a raw material for the production of refuse-derived fuel and to protect surface and ground waters against biological contamination during transfer and storage creates a lot of problems. This paper evaluates the antimicrobial potential of non-equilibrium plasma in relation to the selected groups of microorganisms found in humid waste. The proposed research is to determine whether mixed municipal waste used for the production of alternative fuels can be sterilized effectively using low-temperature plasma generated in a gliding arc discharge reactor in order to prevent water contamination and health risk for working staff. This work assesses whether plasma treatment of raw materials in several process variants effectively eliminates or reduces the number of selected groups of microorganisms living in mixed municipal waste. The presence of vegetative bacteria and endospores, mold fungi, actinobacteria Escherichia coli, and facultative pathogens, i.e., Staphylococcus spp., Salmonella spp., Shigella spp., Enterococcus faecalis and Clostridium perfringens in the tested material was microbiologically analyzed. It was found that the plasma treatment differently contributes to the elimination of various kinds of microorganisms in the analyzed raw materials. The effectiveness of sterilization depended mainly on the time of raw materials contact with low-temperature plasma. The results are very promising and require further research to optimize the proposed hygienization process.

The article evaluates the effect of small selected doses of biochar addition (0%, 1.5%, 3% and 5%, wet weight) on the composting process of the organic fraction of municipal solid waste (OFMSW) with a low initial C/N ratio under real conditions. The low C/N composting mixtures with addition of biochar at low rates can have a positive effect on the compost quality and on the reduction of N losses in compost. The novelty of this work consists in studying the impact of small biochar doses on the composting process at full-scale. The research was conducted under real conditions in the Brno Central Composting Plant (Czech Republic) receiving food waste, grass, straw, sawdust, mineral waste, paper, wood and sewage sludge for processing. The experimental processing time was 12 weeks. We evaluated changes in carbon (C), nitrogen (N), moisture content (MC), organic matter (OM), respiration activity (AT4), as well as changes in the microbiocenotic composition of microorganisms colonizing the processed waste. OFMSW with the addition of biochar and compost were assessed for the content of heavy metals (HM). It was found out that biochar reduced the compost toxicity. The resulting compost with the addition of biochar exhibited higher moisture content and lower waste density. Biochar had an impact on N retention during composting but it did not change the course or accelerate the composting process. The highest OM loss (62.6%) was observed in the OFMSW with no biochar addition. The abundance of potentially pathogenic microorganisms clearly decreased during the OFMSW composting process with the addition of biochar.

The aim of this study was to assess bactericidal properties of nanosilver obtained with ascorbic acid (vitamin C) as a reducing substance, against environmental strains of Gram-positive (Staphylococcus) and Gram-negative bacteria (Escherichia coli). Silver nanoparticles were obtained by a simple and fast method of chemical reduction in mild synthesis condition using substrates not classified as dangerous and commonly found in plants. Bacterial susceptibility to nanosilver was determined using the disk-diffusion method. Gram-positive bacteria were less susceptible to bactericidal action of nanosilver and minimum inhibitory concentration was higher for these bacteria. However, susceptibility of individual isolates of different species to nanosilver was very diverse. The range of growth inhibition zones indicates that the resistance to different concentrations of nanosilver was a strain-characteristic, not species-related feature. The study of effective nanomaterials synthesis and applicability appears to be an extremely important element in the development of nanotechnology, especially in terms of the risks assessment. Obtained results have a real chance to be an important step toward creating a new generation of disinfectants without toxic effects on the environment and higher organisms.

The aim of the study was to determine the antimicrobial resistance profile and the occurrence of extended-spectrum beta-lactamase genes and to analyze the genetic diversity of Escherichia coli strains isolated from the environment of horse riding centers. The study was conducted using E. coli strains isolated from the air, manure, and horse nostril swabs in three horse riding centers differing in the system of horse keeping-stable (OJK Pegaz and KJK Szary) and free-range (SKH Nielepice). Resistance to antibiotics was determined using the disk-diffusion method, and the PCR technique was employed to detect the extended-spectrum β-lactamase (ESBL) genes, while the genetic diversity of strains was assessed by rep-PCR. A total of 200 strains were collected during the 2-year study, with the majority isolated from KJK Szary, while the smallest number was obtained from SKH Nielepice. The strains were mostly resistant to ampicillin, aztreonam, and ticarcillin. The tested strains were most frequently resistant to one or two antibiotics, with a maximum of ten antimicrobials at the same time. Two multidrug-resistant (MDR) strains were detected in OJK Pegaz while in KJK Szary there were two MDR and one extensively drug-resistant (XDR) strain. The ESBL mechanism was most frequently observed in OJK Pegaz (20.31% of strains) followed by KJK Szary (15.53% of strains) and SKH Nielepice (15.15% of strains). Among the ESBL-determining genes, only blaTEM and blaCTXM-9 were detected-blaTEM was mostly found in KJK Szary (53.40% of strains), while the second detected gene-blaCTXM-9-was most frequent in SKH Nielepice (6.06% of strains). The rep-PCR genotyping showed high variation among the analyzed strains, whereas its degree differed between the studied facilities, indicating that the type of horse keeping (stable vs. free-range) affects the genetic diversity of the E. coli strains. Having regard to the fact that the tested strains of E. coli were derived from non-hospitalized horses that were not treated pharmacologically, we can assume that the observed antimicrobial resistance may be of both-natural origin, i.e., not the result of the selection pressure, and acquired, the source of which could be people present in the horse riding facilities, the remaining horses which were not included in the study, and air, as well as water, fodder, and litter of the animals. Therefore, it can be concluded that the studied horses are the source of resistant E. coli and it is reasonable to continue monitoring the changes in antimicrobial resistance in those bacteria.

The purpose of the study was to identify species, to determine the drug resistance profile, and to evaluate the occurrence of genes responsible for the development of methicillin resistance in Staphylococcus bacteria isolated from the environment of horse riding centers. Staphylococci were isolated from air, manure, and nostrils of horses located in three horse riding centers, differing in horse stabling system—box stall stabling (OJK Pegaz and KJK Szary) and free-range stabling (SKH Nielepice). The dominant species was Staphylococcus vitulinus. A large variation in the frequency of occurrence of individual species between horse riding centers was determined. Resistance to antibiotics was determined by means of disc diffusion method and polymerase chain reaction technique to detect mecA genes responsible for methicillin resistance. In total, 408 strains were collected, most from SKH Nielepice, and least from OJK Pegaz. The highest resistance was found to gentamicin and tetracycline. Multidrug-resistant isolates were also detected in KJK Szary (10), in SKH Nielepice (5), and in OJK Pegaz (4). Methicillin resistance determined by disk diffusion assay was found in 23 strains, while the mecA gene was detected in 142 isolates. A total of 137 strains holding the mecA gene are coagulase-negative staphylococci (CNS), which, as shown by our own studies, may be a reservoir of methicillin resistance. Most commonly, the mecA gene was found in staphylococci isolated in KJK Szary (61.70%). The mecA gene was detected in five strains that belonged to Staphylococcus aureus species and came from horses in SKH Nielepice, indicating the presence of methicillin-resistant Staphylococcus aureus strains in these animals.

The aim of this research was to evaluate exposure to microbiological aerosol of persons staying in selected office and teaching areas of the university premises. The number and biodiversity of microorganisms constituting the bioaerosol, in particular the Staphylococcus spp., and their drug resistance profile, were determined. Moreover, the influence of temperature, level of airborne particle concentration and the type of ventilation on the number of microorganisms was analysed. The monitoring was carried out using the MAS-100 impactor. The level of airborne particle concentration was measured using the DustTrak II dust meter. The analysis of drug resistance level of staphylococci was carried out using the disk-diffusion method. On the basis of research conducted, the highest microbiological air contamination was found in the biomass lab, due to the research carried out there. On the other hand, no unequivocal link between the concentration of microorganisms present in the air and the type of ventilation used was found. Airborne particles concentrations of PM10 and PM2.5 exceeded the standard limit values – therefore the air was classified as contaminated. In the sampled air, multi-resistant staphylococci were found, which may pose an epidemiological threat to persons staying in the analysed premises.

Biological drying (biodrying) is one of the methods of biological processing of waste, used mainly as part of the mechanical biological treatment of mixed municipal waste. Biological drying uses the heat released during the decomposition of organic matter to reduce the amount of water in dried waste. The aim of the analyses was to provide a microbiological and energetic (fuel) assessment of the process of biodrying of alternative fuel (RDF) obtained by mechanical sorting of mixed municipal waste. The resulting alternative fuel (obtained with just sorting) is characterised by varied moisture content and the presence of diverse groups of microorganisms. The analyses were intended to assess 3 alternative methods of biodrying of alternative fuel in order to produce a stable end product for utility power generation and the cement industry. The analyses were performed using special bioreactors equipped with custom (innovative) fluidised bed, aeration system (air flow rate 500 m3 · h−1), effluents drain systems, post-process air offtake and 4 temperature sensors. The assessment of the impact of the employed bed aeration methods on the quality of the alternative fuel was performed in 3 repetitions with the same external parameters. The obtained results show that after 8 days of biodrying, in the most favourable option, the moisture content in the fuel was reduced to the level of 18.7%, i.e. by 39%, the resulting fuel was microbiologically stable and the calorific value of the fuel was increased on average by 3.2 MJ · kg−1.

On account of the spread of the phenomenon of microorganisms developing drug resistance, new and more effective methods for fighting pathogens are being sought. Therefore, silver nanoparticles (AgNPs) are increasingly used in various fields of industry and medicine due to their bactericidal properties. The aim of this work was to assess the toxicity of nanosilver prepared by chemical reduction process against Escherichia coli strains isolated from horse dung. AgNPs were prepared by chemical reduction involves the reduction of silver salt by a reducing agent in the presence of suitable stabiliser, which is necessary in protecting growth of AgNPs through aggregation. The environmental strains were isolated from horse dung, then identified and evaluated for their sensitivity to AgNPs using the disk diffusion method. Tested AgNPs suspensions exhibit strong antimicrobial activity. The minimum inhibitory concentration of bacterial isolates was found to be 15 μg/mL, AgNPs resistance level for each tested strain were significantly diversified.

This study aimed to determine whether mixed municipal solid waste used for alternative fuel production can be effectively treated with ozone hygienisation in a gaseous phase. It was determined that the use of a fluidised bed reactor and a horizontal reactor with respect to processing the light fraction and the heavy fraction of waste effectively contributes to the elimination or reduction of the number of selected groups of microorganisms inhabiting mixed municipal solid waste. With the use of microbiological analysis, the presence of vegetative bacteria, spores, fungi, actinomycetes and pathogenic bacteria, i.g. Staphylococcus spp., Escherichia coli, Salmonella spp., Shigella spp., Enterococcus faecalis, and Clostridium perfringens were determined. It was found that ozonation contributed to the elimination of the microorganisms in the tested raw materials in different ways. The efficiency of hygienisation was dependent upon whether the process was performed upon the heavy fraction or the light fraction of waste. In addition, the elimination of microorganisms was influenced by drying the samples—this caused a significant decline in their levels of humidity. Based on the results, it must be considered that presented disinfection process may be used for the hygienisation of raw materials for the production of alternative fuel in the future, given that the source of this fuel can be either a light fraction or a heavy fraction of mixed municipal solid waste.

The aim of this study was to explore the toxicity of silver nanoparticles (AgNPs) synthesized by chemical reduction method assessment with regard to airborne strains of Staphylococcus spp. The first step of the experiment was the preparation of silver nanoparticle suspension. The suspension was obtained by a fast and simple chemical method involving the reduction of silver ions through a reducing factor in the presence of the suitable stabilizer required to prevent the aggregation. In the second stage, varied instrumental techniques were used for the analysis and characterization of the obtained nanostructures. Third, the bacteria of the Staphylococcus genus were isolated from the air under stable conditions with 47 sports and recreational horses, relatively. Next, isolated strains were identified using biochemical and spectrophotometric methods. The final step was the evaluation of the Staphylococcus genus sensitivity to nanosilver using the disk diffusion test. It has been proven that prepared silver nanoparticles exhibit strong antibacterial properties. The minimum inhibitory concentration for tested isolates was 30 μg/mL. It has been found that the sensitivity of Staphylococcus spp. isolated from six identified species differs considerably. The size distribution of bacterial growth inhibition zones indicates that resistance to various nanosilver concentrations is an individual strain feature, and has no connection with belonging to a specific species.

Bacteria of the genus Staphylococcus were isolated from air sampled from living spaces in Krakow (Poland). In total, 55 strains belonging to the genus Staphylococcus were isolated from 45 sites, and 13 species of coagulase-negative staphylococci were identified. The species composition of studied airborne microbiota contains Staphylococcus species that are rarely infectious to humans. Most commonly isolated species comprised S. hominis and S. warneri. The disk-diffusion tests showed that the collected isolates were most frequently resistant to erythromycin. The PCR technique was employed to search for genes conferring the resistance in staphylococci to antibiotics from the group of macrolides, lincosamides and streptogramins. The analyzed Staphylococcus isolates possessed simultaneously 4 different resistance genes. The molecular analysis with the use of specific primers allowed to determine the most prevalent gene which is mphC, responsible for the resistance to macrolides and for the enzymatic inactivation of the drug by phosphotransferase. The second most often detected gene was msrA1, which confers the resistance of staphylococci to macrolides and is responsible for active pumping of antimicrobial particles out of bacterial cells.

After the biowaste composting process, not only is wholesome compost or a substance for increasing soil fertility, but also non-composted waste. Non-composted waste is returned to the composting process or is utilized in the recovery process, e.g. in degraded land reclamation. The purpose of the study was to determine the energy potential of composted biowaste. The research was carried out in Composting Plant in Brno on biowaste samples from households supplemented with biochar in the share of 1.5%, 3%, 5% and without the addition of biochar (the control). The analyses included biowaste and the 3 weeks of intensive phase of the composing process. Sampling for analyzes was performed every week for the first three weeks of the process. The samples were divided into those from which it was possible to obtain compost (with granulation below 20 mm) and the process residue that did not meet the requirements for composts (fraction with a particle size of over 20 mm, containing impurities). The study included: moisture content, ash content, carbon content as well as the heat of combustion and calorific value. The research results revealed that the heat of combustion and the calorific value for samples with grains below 20 mm decreased very quickly during the intensive phase of the composting process. Samples with a particle size above 20 mm can be a source of energy for the power industry, due to the heat of combustion above 9 MJ.kg−1 (and with the addition of biochar above 10 MJ.kg−1), but after prior drying of the waste.

The chemical composition of hop sediments from beer brewing and fermentation gives them the potential for further use. These wastes are not generated in large amounts, but the absence of proper characteristics may lead to processing errors. This study examines the possibility of using hop waste for aerobic biological transformation processes (composting). The study was carried out on two hop sediments from two different technological stages of beer production: hot trub and spent hops. Chemical, microbiological, and biochemical analyses were performed in the composted hop sediments, as was the assessment of phytotoxicity to Lepidium sativum L. The tested feedstocks were partially inhabited by microorganisms and thus safe from an epidemiological point of view, and they were not a source of microbial contamination. Inhibitory properties for plant development were found for hot trub, which most likely result from the organic compound content. If it is only a small portion of its biomass, the mineral composition of hot trub does not exclude the possibility of its composting. Spent hops were characterized by a significant total nitrogen content, which affected the composting process. Composting this sediment required the selection of substrates with a widely C:N ratio.

Biostabilization is a commonly applied method in mechanical-biological treatment (MBT) plants to process municipal solid waste. In many ways, e.g. by applying additives to waste, MBT plant operators strive to enhance the effectiveness of biostabilization, which leads to reducing the time and energy outlays necessary for the process, as well as to minimizing the amount of final stabilized waste directed to landfills. This paper deals with the impact of digestate waste from agricultural biogas plants used as additive to the biostabilization process of undersized fraction from municipal solid waste (UFMSW) on the intensive phase of the process and properties of stabilized waste. The aim of this study was to assess whether, and if so to what extent, the application of digestate waste affects the process. Five different input compositions were tested (without digestate and with the addition of digestate at: 2.5; 5; 7.5 and 10 wt%). Waste treatment time was 2 weeks. Changes in moisture content, organic matter (OM), respiration activity (AT4), bulk density, air-filled porosity, heavy metal content, pH, carbon to nitrogen ratio, as well as composition of process gases emitted were evaluated. Additionally, microorganisms (including pathogens) inhabiting the processed waste in the aspect of waste sanitation were analyzed. It was found that the addition of digestate at 2.5, 5 and 7.5 wt% extended the duration of the thermophilic phase and decreased the CO2 content in process gases. The addition of digestate at 2.5 wt% and 5 wt%, decreased also OM by approx. 25% of the initial value and AT4 by approx. 30%. It was also proved that the addition of digestate favors the limited sanitation of UFMSW. As a result of the research, it was found that the addition of digestate at 2.5 wt% and 5 wt% is sufficient to accelerate the aerobic biological degradation of UFMSW.

Introduction. This study was aimed to assess the microbiological quality of water in the Nowohucki Reservoir (Kraków, Poland) as well as to determine whether its waters contain microorganisms potentially dangerous from an epidemiological point of view. Material and methods. Microbiological analyses included the determination of the number of mesophilic and psychrophilic bacteria, coliforms, fecal E. coli, as well as E. faecalis, C. perfringens, Staphylococcus spp. and Salmonella spp.. Water samples were collected 4 times per year on April 27th 2015 (spring), July 10th 2015 (summer), October 12th 2015 (autumn) and December 29th 2015 (winter) at 5 points within the area of the reservoir. Water and air temperature was measured onsite. Results. It was found that the prevalence of the analyzed microorganisms was affected by changing water and air temperature as well as by using this reservoir during holiday season for swimming purposes by local residents. All analyzed microbiological indicators of poor water quality were found in the analyzed water samples, which may pose a potential health risk to people swimming in the considered reservoir. Conclusions. From an epidemiological point of view, it is reasonable to include the Nowohucki Reservoir into a constant sanitary monitoring programme.

Introduction. In the atmospheric air, fungal spores of the genus Fusarium are present which may be resistant to antifungal drugs used in medicine. The aim of this study was to determine the sensitivity to selected antimycotics, and to identify the MIC (minimum inhibitory concentration) for strains belonging to the species F. culmorum. Material and methods. Fungal strains were isolated from atmospheric air sampling in the vicinity of fields where winter wheat was cultivated. Evaluation of susceptibility to antifungal drugs was carried out using E-test strips. Results. All isolates were characterized by resistance to ketoconazole, itraconazole and fluconazole. MIC for amphotericin B was 0.023 µg · cm–3, for voriconazole 0.016 µg·cm–3, for posaconazole 0.006 µg·cm–3 and for caspofungin 0.25 µg·cm–3. Among the isolates tested, 8 were resistant to voriconazole, 3 resistant to posaconazole and 10 resistant to amphotericin B. Conclusions. The examined strains presented different sensitivity to antifungal drugs. The strongest fungicidal activity was found in the case of: posaconazole, voriconazole and amphotericin B. In the atmospheric air there may exist strains of F. culmorum which have natural resistance to some antimycotics.

During the storage of spent polymer materials derived from municipal solid waste, which contain biodegradable impurities, an intense growth of microorganisms takes place. The aerobic metabolism of microorganisms may cause these materials to combust spontaneously and to become a real epidemiological risk for humans. The aim of the research is to determine the optimal addition of calcium oxide (CaO), which effectively reduces the number of selected microorganism groups populating the analyzed materials, in which spent polymers represent a significant fraction: refuse-derived fuel (RDF) and an undersize fraction of municipal solid waste (UFMSW). The main novelty of the experiments is to assess the benefits of using the commonly available and cheap filler (CaO), to hygienize the material and to reduce the fire hazard arising from its storage. During the mixing of spent polymer materials with pulverized CaO (mass shares: 1, 2, and 5% CaO), temperature changes were monitored using thermography. Moisture content (MC), pH, respiration activity (AT4) and bacterial count were determined before and after the experiment. During the addition of CaO (especially when the content was at 5%) to the UFMSW, higher maximum temperatures were obtained than in the case of RDF analyses, which may be the result of a high percentage of the biodegradable fraction and higher MC of the UFMSW. In all cases the waste temperature did not increase again after 3 min. CaO used in the experiment effectively limited the number of microorganisms. The addition of 5% of CaO has showed the strongest antimicrobial properties, and it can be recommended for hygienization of the analyzed materials and for the reduction of the risk of self-heating during their storage in windrows.

The aim of the paper was an assessment of the effect of a commercial biopreparation, a liquid bacteria composite intended for improvement of biowaste processing efficiency, on the course of aerobic biostabilization process of the undersize fraction (waste separated from mixed municipal solid waste) mixed with municipal sewage sludge, as well as an assessment of the quality of initially obtained stabilized waste. Presented research comprised analyses of raw materials and mixtures used in the process and the waste obtained after 2 stage process (2 week intensive phase in a bioreactor and 6 week second phase - maturation in the compost pile). Moisture content, organic matter, C and N contents, C/N ratio and pH were analysed. Moreover, the number of parasites and microorganisms in waste was estimated. The process temperature was monitored. On the basis of conducted analyses it was stated that the biopreparation tested does not fulfil its basic role, so it should not be used in sewage sludge and municipal solid waste hygienization process. Physicochemical analysis indicated an insufficient progress in the properties of treatment waste. The number of all investigated microorganisms increased considerably after aerobic biostabilization process, despite the added biopreparation, which according to its manufacturer’s declaration was supposed to reveal antimicrobial effect. Moreover, presence of a large number of live parasite eggs was found in all analysed samples, which makes environmental application of the tested biowaste impossible.

This study was aimed to determine the impact of risk element content on the prevalence of the selected microbial groups in industrial soils of one of the steelworks in Poland. The concentration of heavy metals: Cd, Cr, Cu, Hg, Fe, Ni, Pb and Zn along with soil pH and the number of mesophilic bacteria, fungi, actinomycetes and Azotobacter was assessed in 20 soil samples. The limit concentrations of Cd, Pb and Zn were exceeded in five sites. However, even in these strongly contaminates sites, the studied microorganisms were abundant. The correlation between the concentration of heavy metals and microbial numbers was very weak and statistically insignificant. High numbers of fungi were observed in the contaminated sites, which was particularly interesting in one of the sites, strongly contaminated with Cd, Pb and Zn.

Introduction. The purpose of this study was to evaluate the microbiological quality of the air at the selected places which are located in Cracow and also to determine the influence of weather conditions, such as temperature, humidity and pollination on the number of microorganisms. Material and methods. Samples of air were taken during spring, summer, autumn and winter. The analyses were carried out by using a single-stage MAS-100 impactor (Merck) and repeated three times. Results were compared to guidelines which are included in Polish Standards. Results. The results of the study suggest that there is correlation between seasons and number of microorganisms. Moreover the number of microbes depends on location. The highest concentration of all groups of microorganisms occurred in summer and autumn. Conversely the lowest number of microbes occurred in winter. The results indicated that the composition of bioaerozol is typical and consists of fungi: Cladosporium spp., Mucor spp., Penicillium spp., Alternaria spp., Trichothecium spp., Fusarium spp., bacteria: Micrococcus spp., Diplococcus spp., Tetracoccus spp., Streptobacillus spp., Staphylococcus spp. and actinomycetes. Conclusions. The results revealed that there is a big difference in the occurence of microorganisms and it depends on season and location as well. However our study indicates that air does not pose a microbiological threat to runners

Introduction. The quality of indoor air is one of the most important factors affecting health and well-being of people, who inhale 10 m3 of air every day and spend 80–95% of life indoors. The aim of this research was to evaluate the occurrence of airborne fungi, along with assessment of air pollution and microbiological hazard for humans, in 45 public utility buildings in Cracow. Material and methods. The study was carried out in four groups of buildings, including teaching facilities of the University of Agriculture and Jagiellonian University, churches, shopping malls and hospitals with outpatient clinics. Four sites located in the open air were chosen as control. The air sampling was carried out with MAS-100 impactor. Fungi were enumerated on Malt Extract Agar and the results were expressed as colony forming units (CFU) per m3 of air. The isolated fungi were identified by comparing macroscopic and microscopic observations with taxonomic monographs. Results. Mean concentration of airborne fungi was highest in the teaching facilities (1970 CFU/m3). These were also the sites where the largest range of fungal concentration was observed, i.e. from 0 to 23,300 CFU/m3. The lowest mean concentration (99 CFU/m3) including range was observed in hospitals (from 0 to 327 CFU/m3). Species identification of the fungal isolates revealed the presence of allergenic fungi (Alternaria and Cladosporium) in the examined spaces. Moreover, some strains were also identified as potentially toxigenic species, such as Penicillium expansum or Aspergillus niger. Conclusions. The concentration range of airborne fungi varied significantly between the tested spaces. Although the observed concentration of airborne fungi in the majority of buildings was quite low, detection of potentially toxigenic fungi indicates the need for monitoring of both concentration and composition of fungal aerosol in public utility buildings.

The aim of this study was to assess the microbiological quality of air in three horse riding centers differing in the horse keeping systems. The air samples were collected in one facility with free-range horse keeping system and two with box stalls of different sizes. The samples were collected over a period of 3 years (2015–2017), four times per year (spring, summer, autumn, winter) to assess the effect of seasonal changes. The prevalence of aerobic mesophilic bacteria, mold fungi, actinomycetes, Staphylococcus spp., and Escherichia coli was determined by the air collision method on Petri dishes with appropriate microbiological media. At the same time, air temperature, relative humidity, and particulate matter concentration (PM10, PM2.5) were measured. It was found that the horse keeping system affects the occurrence of the examined airborne microorganisms. Over the 3-year period of study, higher temperature and humidity, as well as particulate matter concentration—which notoriously exceeded limit values—were observed in the facilities with the box-stall system. The air sampled from the largest horse riding center, with the largest number of horses and the box-stall system of horse keeping, was also characterized by the heaviest microbiological contamination. Among others, bacteria from the following genera: Staphylococcus spp., Streptococcus spp., Bacillus spp., and E. coli and fungi from the genera Aspergillus, Fusarium, Mucor, Rhizopus, Penicillium, Trichothecium, Cladosporium, and Alternaria were identified in the analyzed samples.

This study aimed to determine the susceptibility of Fusarium spp. strains isolated from cereals to selected heavy metals, fungicides and silver nanoparticles. The experiments were conducted using 50 Fusarium strains belonging to five species: F. graminearum, F. culmorum, F. oxysporum, F. sporotrichioides and F. avenaceum. The strains were found to be highly resistant to Pb(2+) and Zn(2+). Medium resistance to Cu(2+) and Mn(2+) and low resistance to Cd(2+) and Fe(3+) was also observed. Among the tested fungicides, formulations containing azoxystrobin, prochloraz and tebuconazole proved to be the most effective in inhibiting the growth of fungi, as they affected fungal growth in each of the applied doses. Susceptibility of Fusarium spp. to nanosilver, demonstrated in this study, shows the legitimacy of using nanostructures as fungicidal agents. The results confirm high diversity of the analyzed fungal species in terms of susceptibility to the tested substances, and encourage to continue research on the resistance of Fusarium spp. to various fungicidal agents.

The occurrence of Azotobacter spp., which has beneficial effects on plant development, is related to various soil properties, such as pH and fertility. This study evaluated the prevalence of Azotobacter spp. in industrial (H) and agricultural soils (P) in Nowa Huta, Cracow and determined the phenotypic and genetic diversity of these bacteria. The examined bacteria were present in 40% of H and in 50% of P soils. Taxonomic identification of the bacterial isolates indicated the presence of three species--A. salinestris, A. chroococcum and A. vinelandii. The genetic diversity, determined using two fingerprinting methods--Random Analysis of Polymorphic DNA (RAPD) and Rep-PCR (BOX) revealed high level of population diversity. In AMOVA analysis most of diversity was attributed to within-population variation (76-85%), and only 3.78-6.18% was associated with among-group H and P variation. Global test of differences revealed distinct population structure within bacterial strains isolated from H and P areas only for BOX markers (Fst = 0.05732, P = 0.00275). Phenetic analyses: UPGMA and DCA better discriminated H and P groups based on RAPD data. Both BOX and RAPD methods provided an insight into the genetic complexity of Azotobacter spp. variation in soils of different land-use types.

The aim of this study was to assess the species composition of airborne Staphylococcus spp. in public premises, to determine the methicillin resistance of the isolates and the prevalence of mecA gene, determining resistance to β-lactams. In total 65 Staphylococcus strains were isolated from 54 sites. Four strains exhibited phenotypic methicillin resistance, while the presence of mecA gene was found in 11 strains. The results of both assays were compared, showing that the phenotypic tests revealed methicillin resistance only in 36% of the examined samples. This study revealed high species diversity among airborne Staphylococcus spp. population, which consists of multidrug resistant strains.

Bacterial Escherichia coli isolates were derived from waters of the Nowohucki Reservoir (Cracow, Poland) in summer and winter seasons. In total, 94 strains, identified as E. coli, were isolated from five sampling sites in the area of the reservoir. Based on the disk-diffusion tests, it was found that the tested isolates were predominantly resistant to ticarcillin and ampicillin. Numerous multi-drug resistant strains were detected, which however did not exhibit the ESBL phenotype. However, PCR approach allowed to detect ESBL-mechanism genes (CTX-M3, OXA, SHV, and TEM) in as much as 38 % of E. coli isolates. These results were coupled with significant molecular diversity of the E. coli strains revealed in BOXA1R-based rep-PCR technique.

The present study aimed to identify the effect of heavy metal concentration and soil pH on the abundance of the selected soil microorganisms within ArcelorMittal Poland steelworks, Cracow. The analysis included 20 soil samples, where the concentration of Fe, Zn, Cd, Pb, Ni, Cu, Mn, Cr and soil pH were evaluated together with the number of mesophilic bacteria, fungi, Actinomycetes and Azotobacter spp. In the majority of samples soil pH was alkaline. The limits of heavy metals exceeded in eight samples and in one sample, the concentration of Zn exceeded 31-fold. Chromium was the element which most significantly limited the number of bacteria and Actinomycetes.

The analysis was conducted using 50 isolates of fungi of the genus Fusarium belonging to the species classified as major trichothecene mycotoxin producers: F. graminearum, F. culmorum, F. sporotrichioides, and F. poae. The tested fungi were isolated from ears of cereal crops in southern Poland during the two growing seasons (2011 and 2012). The aim of this study was to evaluate the prevalence of genes involved in the biosynthesis of trichothecene mycotoxins using the specific PCR tests. Molecular analyses indicated that the genes responsible for the production of trichothecenes (Tri3, Tri5, Tri7, Tri13) were abundant in the examined genetic material. The tested fungal isolates were characterized by a large diversity in terms of the number and composition of the possessed Tri genes. On the other hand, 14 of 50 isolates were found not to carry any of Tri genes.