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PL
Półmaski filtrujące (PF) są stosowane w przemyśle do ochrony przed szkodliwym pyłem. Wwielu miejscach pracy obecne są również mikroorganizmy, co wymaga oceny bezpieczeństwa tego sprzętu. Przeprowadzono analizę zanieczyszczenia mikrobiologicznego pyłu osiadłego w dwóch środowiskach: kompostowni z organicznym pyłem imikroorganizmami oraz cementowni, gdzie głównym zagrożeniem był pył nieorganiczny. Analizę wzrostu mikroorganizmów na materiałach półmasek filtrujących powszechnie stosowanych na tych stanowiskach do ochrony przed pyłem przeprowadzono za pomocą mikroskopii skaningowej. Analizę mikrobiologiczną PF oraz pyłu osiadłego zebranego na stanowiskach pracy przeprowadzono metodą hodowlaną. Do interpretacji wyników wykorzystano równanie Gompertza, umożliwiające prognozowanie dynamiki przeżywalności mikroorganizmów na PF. Pył z kompostowni wspomagał wzrost badanych mikroorganizmów w PF, wydłużając fazę stacjonarną. Pył z cementowni wywoływał przeciwny efekt. W materiałach filtracyjnych obserwowano wzrost liczby mikroorganizmów o 2-6 rzędów wielkości w skali logarytmicznej w ciągu zaledwie 30 min. Potwierdza to potrzebę skrócenia standardowego czasu stosowania PF w narażeniu na czynniki pyłowe, gdy w środowisku pracy obecne są także czynniki biologiczne. Ustalenia te mają kluczowe znaczenie wkontekście bezpieczeństwa stosowania PF w środowisku pracy, w którym współistnieją czynniki pyłowe organiczne/nieorganiczne i biologiczne.
EN
Samples of settled dust collected from workplaces in the composting plant and cement plant, as well as samples of the materials of filtering facepiece respirators (FFR) used by employees working there, were analyzed by microbiol. culture method. The degree of microbial contamination was also analysed using SEM imaging. Dust deposition on FFR collected from the tested surfaces was also simulated and the growth of microorganisms was analyzed using SEM imaging. Prediction of the survival dynamics of microorganisms on FFR was performed using the Gompertz eqn. Org. dust provided better conditions for the growth of microorganisms than inorg. dust. Dust from the composting plant supported the growth of the tested microorganisms, compared to the control variant (without dust), and dust from the cement plant, esp. in high concns., led to the opposite effect.
EN
This paper refers to several aspects of research studies supporting the oil and gas industry – in particular underground gas storage (UGS) in depleted deposits and salt caverns – and focuses on questions related to the formation of hydrogen sulphide contamination in reservoir conditions as well as on methods for limiting unfavourable biogenic phenomena. The main problem found at gas storage facilities is the activity of sulphate reducing bacteria (SRB). The elimination or limitation of H2S generation in microbiologically contaminated environments have been the subject of many extensive studies. Biocides, biocorrosion inhibitors and H2S scavengers are widely applied to protect reservoir structure, gas storage infrastructure as well as water-based drilling fluids from the negative effects of bacterial activity. One of the most popular biocidal products, recommended for oil and gas industry are triazine derivatives, laboratory tested in the presented biomonitoring studies. Triazine products prove very effective in biomass reduction and elimination of anaerobic bacteria, especially SRB. Before any industrial operation (based on technology of using biocides), it was necessary to analyse the sulphur compounds in the stored natural gas in different exploitation gas wells of UGS. It was also necessary to investigate the selection of a specific biocidal product and its proper concentration. A concentration that is too low may even stimulate the microbial growth; since the substance is not toxic for microorganisms, they may start to metabolise it. Moreover, the wrong choice of biocides may even generate an economic loss or environmental hazard. Generally, the application of biocides, H2S scavengers and nitrate-based treatment are one of the most effective world strategies to decrease microbiological contamination, which affects various areas of the oil and gas industry. These products have also been successfully applied to control bacterial growth in Polish natural gas wells. The issue of the influence of microorganisms and biomass on the permeability of reservoir rocks was also presented. In addition, the paper refers to biodegradation processes, that take place in the environment of drilling fluids. Also, the issue of choice of biocide/ H2S scavenger preparations for industrial applications is presented. The choice of chemicals includes efficiency tests of nanoparticles in contaminated media.
PL
Artykuł dotyczy kilku aspektów prac badawczych stanowiących wsparcie dla przemysłu nafty i gazu, głównie podziemnego magazynowania gazu w złożach sczerpanych i kawernach solnych. Skoncentrowano się na zagadnieniach związanych z powstawaniem skażeń siarkowodorowych w warunkach złożowych oraz na metodach ograniczania niekorzystnych zjawisk o charakterze biogennym. W obiektach magazynowania gazu duży problem stanowią aktywne bakterie redukujące siarczany z grupy SRB. Eliminacja lub ograniczenie zawartości siarkowodoru w skażonych mikrobiologicznie środowiskach jest przedmiotem wielu prac badawczych. Preparaty takie jak biocydy, inhibitory biokorozji lub neutralizatory H2S są często stosowane do ochrony struktury złożowej, obiektów magazynowych, jak również wodnodyspersyjnych płuczek wiertniczych przed niekorzystnym oddziaływaniem bakterii. Jednym z najbardziej popularnych środków biobójczych stosowanych w przemyśle nafty i gazu są pochodne triazyny, testowane również w ramach omawianych badań biomonitoringowych. Produkty triazynowe są bardzo efektywne w procesach redukcji biomasy oraz eliminacji bakterii beztlenowych, głównie z grupy SRB. Przed każdorazowym zabiegiem przemysłowym (opartym na technologii stosowania biocydów) niezbędne jest przebadanie zawartości związków siarki w magazynowanym gazie, pobranym z różnych odwiertów eksploatacyjnych podziemnego magazynu. Konieczny jest również dobór odpowiednich preparatów oraz wytypowanie optymalnych stężeń preparatów biobójczych. Zbyt niskie stężenie może bowiem stymulować wzrost mikroorganizmów, które są zdolne do wykorzystania danej substancji w procesach metabolicznych. Ponadto niewłaściwy dobór biocydu może powodować straty i wpływać negatywnie na środowisko przyrodnicze. Generalnie stosowanie biocydów, neutralizatorów siarkowodoru i związków azotanowych stanowi jedną z najbardziej skutecznych światowych strategii ograniczenia skażeń mikrobiologicznych w wielu obiektach złożowych. Wymienione wyżej środki chemiczne były również z sukcesem stosowane w polskich odwiertach gazowych. W artykule przedstawiono także problem wpływu mikroorganizmów i biomasy na przepuszczalność skał zbiornikowych. Ponadto nawiązano do zjawisk o charakterze biodegradacyjnym, które mają miejsce w środowisku płuczek wiertniczych. Zaprezentowano problematykę dotyczącą wspomnianego doboru preparatów typu biocyd/H2S scavenger do zastosowań przemysłowych z uwzględnieniem badań efektywności działania nanocząsteczek w skażonych mediach.
3
EN
The aggregate of various taxonomic groups of microorganisms colonising living organisms is known as the microbiome. The plant microbiome encompasses a wide network of biological, chemical and metabolic interactions between the plant and microorganisms (mainly algae, bacteria and protozoa). The relationships between microbes and peatland plants, particularly carnivorous plants, are a very interesting subject that is still little understood. Microbes colonising carnivorous peatland plants may be present in their traps or on the surface of the plant. Previous research on the relationships between the microbiome composition of carnivorous plants and the external factors influencing it directly and indirectly is still inadequate. There is a lack of review articles analysing the current state of knowledge regarding carnivorous plant-microbiome interactions. This review of the literature is a collection of data on the functioning of the microbiome of carnivorous plants growing in peatland ecosystems. In addition, it summarises the available information on host–microorganism relationships.
EN
The application of biotechnological methods in the metallurgical industry has the potential to provide an environmentally friendly and cost-effective direction of development. Thiobacillus ferrooxidans, a thionic bacterium, and the microalga Chlamydomonas reinhardtii TN-72 CH were used as complex reagents for extracting gold from sulfide mineral raw materials. The sorption properties of modal and productive multicomponent gold-bearing solutions were studied. The sorption characteristics of the biosorbents were compared with those of sorbents currently used in gold production – the synthetic resin AM2B and GoldCarb activated carbon. The conducted research studying the sorption properties and survival ability of the microalga C. reinhardtii TN-72 CH will make it possible to develop an industrial technology for extracting metal in the hydrometallurgical cycle of gold production. The use of microorganisms in gold hydrometallurgy as an alternative to cyanide methods will reduce the load on the environment while reducing the cost of the technology. In the process of leaching gold-bearing raw materials by microorganisms, even submicroparticles of gold are released, which makes the processing of poor and refractory ores promising. Preliminary biooxidation increases the effectiveness of thiosulfates in terms of both time and gold recovery.
EN
Research into the correlations among components of soil biota is of significant importance for effective management of agroecosystems in organic agricultural production. Organic cultivation technologies contribute to increased nitrogen and phosphorus content in the soil, while reducing levels of P2O5 and K2O compared to inorganic methods. The influence of organic residue decomposers on macroelement composition in the soil has been examined, revealing a minimal impact on their levels. Organic technologies promote an augmentation of microorganisms, although there is a potential risk of heightened disease pathogens. It has been observed that under organic cultivation conditions, there is more intense tissue degradation, potentially attributed to higher microorganism activity. Transitional cultivation methods yield lower rates of degradation in comparison to organic techniques. The impact of organic technologies on the quantity of earthworms, nematodes, and springtails in the soil has been investigated. Organic practices have shown to increase their population, creating a favorable environment for soil biological indicators. Particular attention is given to correlation relationships between microorganisms responsible for nitrogen and phosphorus accumulation and the fungal component. High correlation values (r = 0.72–0.89) underscore the significance of comprehending these associations when employing organic cultivation methods. The study of correlations among soil biota components in organic production presents a promising task for the effective utilization of resources and the assurance of sustainable agroecosystem development.
PL
Celem badań była ocena jakości mikrobiologicznej powietrza trzech klatek schodowych w blokach mieszkalnych wielorodzinnych. Badano wpływ pory roku i temperatury na liczebność oraz bioróżnorodność mikroorganizmów w bioareozolu klatek schodowych. Wszystkie badania zostały wykonane za pomocą aeroskopu MAS-100 (Merck), metodą uderzeniową. Stwierdzono przekraczające normy stężenia promieniowców oraz gronkowców w powietrzu atmosferycznym oraz powietrzu wybranych klatek schodowych. Pora roku oraz temperatura powietrza mają wpływ na stężenie mikroorganizmów w powietrzu. Wiek budynku, dostępność światła oraz system wentylacji mogą mieć również wpływ na stężenie wskaźników czystości mikrobiologicznej powietrza.
EN
The aim of the study was to assess the microbiological air quality in three staircases of multifamily residential buildings. The study examined influence of season and air temperature on the abundance and biodiversity of microorganisms in the bioaerosol of stairwells. All studies were conducted using an impact method with the MAS-100 aerosol sampler (Merck). Concentrations of actinomycetes and staphylococci in both atmospheric air and selected stairwells exceeded norms. Season and air temperature have an impact on microbial concentrations in the air. The age of the building, light availability and ventilation conditions were also identified as potential factors influencing the concentration of specific microbial groups in the bioaerosol.
EN
The indoor air quality is of great importance for the health of people. Appropriate selection of methods, parameters and conditions for the analysis makes it possible to obtain the results that reliably reflect the actual state of affairs. The aim of this study was to compare the results of microbiological air analysis in selected rooms of the Biotechnology Center obtained using the sedimentation method and the impaction method. During the research, the SMA (for total bacteria number) and Sabouraud media (for total fungi number) were exposed to different times in sedimentation analysis and to different air volumes in the impaction method. In the case of the sedimentation method, significant differences were found in the total number of bacteria and fungi in 3 out of 7 rooms depending on the time of exposure. In the case of the impaction method, it was 4 out of 7 rooms for bacteria and 2 out of 7 for fungi, depending on the analysed volume of air. The comparison of the methods showed that 4 out of 6 rooms had higher number of microorganisms when impactor was used.
EN
The composting process is a natural method of waste disposal. Decomposition of organic matter occur with the participation of various groups of microorganisms. Using glyphosate-based herbicides aims to reduce agricultural losses. Biodegradation of glyphosate in soil is obtain with bacteria and fungi and may affect their functioning. The purpose of this study was evaluating the effects of glyphosate on bacterial diversity during composting and to monitor potential changes in community structure and species abundance. The addition of glyphosate did not affect the morphology of the tested groups of bacteria and did not cause changes in the morphological structure of fungi. Sampling after 10 minutes, 24 hours, 48 hours and 72 hours showed that the abundance of bacterial colonies changed over time compared to the control groups. However, the results suggest that the addition of glyphosate is insufficient to influence the composting process, thus disturbing the specific biocenosis.
9
EN
The subject of microbiological tests of coolants presented in the work is the cutting fluid (emulsifying oil) of Fuchs ECOCOOL 68 CF3. The liquid was taken from the tanks of three different numerically controlled machines (Lasertec 65, MillTap 700, CTX beta 1250 TC), used with different intensity. The five most characteristic and popular media were used in the study: nutrient agar - plain, TSA medium (tryptone-soy-agar), medium with dichloran, rose bengal and chloramphenicol, Sabouraud agar with Chloramphenicol, Czapka agar. The incubation time was dependent on the type of microorganisms. After the specified time, the plates inoculated on the medium were subjected to visual observations and under the Leica DM 500 microscope. As a result of the observation, the following types of microorganisms (fungi and bacteria) were detected: Aspergillus Niger Tiegh, Candida Albicans, Saphylococcus Aureus, Micrococcus Luteus and Escherchia Coli and Citrobacter Freundia. The assessments were made in fixed periods. The results are presented as a function of the intensity of the use of cutting fluids. Microbiological analysis of machining fluids will allow for optimizing the time periods of using coolants and will also contribute to the protection of the operator's health and indirectly "extending the life cycle" of the technological machine.
PL
Jakość wody pitnej podlega bardzo restrykcyjnym regulacjom, a systemy wodne monitorowane są m.in. pod kątem mikroorganizmów istotnych dla zdrowia publicznego. W.systemach wodnych dominują heterotroficzne bakterie saprofityczne, oznaczane jako HPC (ang. Heterotropic Plate Count), jednak nie należy ich lekceważyć, ponieważ odgrywają one istotną rolę w tworzeniu biofilmów. Oprócz populacji bakteryjnych, często w systemach wodnych występują także grzyby z rodzajów: Penicillium, Phialophora, Cladosporium i Acremonium, drożdże, pierwotniaki (np. Bodo), wolne ameby (np. Hartmannela vermiformis, Vannella mira, Cochliopodium minutum), orzęski oraz glony. Wszystkie drobnoustroje mogą uczestniczyć w tworzeniu biofilmów na powierzchniach kontaktujących się z wodą. Biofilmy wpływają istotnie na mikrobiologiczną i organoleptyczną jakość wody pitnej a także na procesy korozyjne. Omówiono związki przyczynowe między tworzeniem biofilmów a pochodzeniem wody surowej, jej składem biologicznym i charakterystyką chemiczną.
EN
The quality of drinking water is subject to very strict regulations, and the water systems are regularly monitored, e.g. for microorganisms important to public health. Water systems are dominated by heterotrophic saprophytic bacteria, called HPC (Heterotropic Plate Count), but they should not be underestimated as they play an important role in the formation of biofilms. Apart from bacterial populations, fungi of the genera Penicillium, Phialophora, Cladosporium and Acremonium, yeasts, protozoa (e.g. Bodo), amoebas (e.g. Hartmannela vermiformis, Vannella mira, Cochliopodium minutum), ciliates and algae are also frequently present in water systems. All these microorganisms may participate in the formation of biofilms on surfaces in contact with water. Biofilms significantly affect the microbiological and organoleptic quality of drinking water as well as corrosive processes. The article discusses the causal relationships between biofilm formation and the origin of raw water, its biological composition and chemical characteristics.
PL
W artykule dokonano przeglądu wybranych zniszczeń biologicznych pozytywów i negatywów fotograficznych srebrowo-żelatynowych wykonanych na podłożach papierowych oraz błonach wytworzonych z pochodnych celulozy (nitroceluloza, octany celulozy). Obiekty fotograficzne są konglomeratem różnych materiałów i substancji chemicznych, będących źródłami różnych pierwiastków, w tym kluczowych dla rozwoju form biologicznych – węgla i azotu. Obecność w dawnych fotografiach oraz ich oprawach takich substancji jak żelatyna, skrobia, czy celuloza oraz niekorzystne, wilgotne warunki przechowywania zbiorów fotograficznych powodują, że mikroorganizmy i owady odgrywają istotną rolę w ich niszczeniu. Celem pracy było przedstawienie przykładów zniszczeń obiektów fotograficznych pochodzących z różnych zbiorów. Zniszczenia te przybierają różną formę oraz charakteryzują się różnorodną intensywnością – od skali mikroskopowej aż pod destrukcję całych fotografii.
EN
The biological damage of silver and gelatin photographic positives and negatives made on paper substrates and films made from cellulose derivatives (nitrocellulose, cellulose acetates) were examined. Photographic objects are a conglomerate of various materials and chemicals that are sources of various elements, including key ones for the development of biological forms – carbon and nitrogen. Presence in old photos and their binding of substances such as gelatin, starch or cellulose and unfavorable, humid conditions storing photographic stocks cause microorganisms and insects to play important role in their destruction. The study presents examples of damage to photographic objects from various collections. This destruction takes many forms as well .They are characterized by various intensity – from the microscopic scale to the destruction of the whole photograph.
EN
This paper discusses the effect of constant electric field on the geometrical parameters of selected microorganisms. In the experiment different time of exposure of suspension of microorganisms to constant electric field was applied and then the cell area and its diameter were determined. It was found that with increasing stimulation time the diameter and area of the cells relatively decreased in the case of Enterococcus faecalis strain ATCC 29212 as well as Candida krusei strain ATCC 14243. It should be noted, however, that in the case of Enterococcus faecalis ATCC 29212 cells the area and diameter of the cells after stimulation are higher than in the case of untreated cells, while in the case of Candida krusei ATCC 14243 both the area and diameter of the cells after stimulation are lower than in the cells from the control sample.
PL
W artykule omówiono wpływ oddziaływania stałego pola elektrycznego na parametry geometryczne wybranych mikroorganizmów. W doświadczeniu zastosowano zróżnicowany czas ekspozycji zawiesiny mikroorganizmów na oddziaływanie stałego pola elektrycznego a następnie określono powierzchnię komórki oraz jej średnicę. Stwierdzono, że wraz ze wzrostem czasu stymulacji średnica i pole powierzchni komórek względnie zmniejsza się zarówno w przypadku komórek szczepu Enterococcus faecalis ATCC 29212 jak również szczepu drożdżaka Candida krusei ATCC 14243. Należy jednak zaznaczyć, że w przypadku komórek Enterococcus faecalis ATCC 29212 pole powierzchni i średnica komórek po stymulacji jest wyższa niż u komórek nie poddanych takiemu oddziaływaniu, natomiast w przypadku szczepu Candida krusei ATCC 14243 zarówno pole powierzchni jak i średnica komórek po stymulacji jest niższa niż u komórek z próby kontrolnej.
13
Content available Mikrobiologiczna degradacja tworzyw sztucznych
PL
W pracy poruszono zagadnienia związane z biodegradacją tworzyw sztucznych, których usuwanie ze środowiska naturalnego stało się ogromnym wyzwaniem. Opisano proces degradacji polimerów przez mikroorganizmy oraz przedstawiono podstawowe techniki badań pozwalające na zbadanie stopnia rozkładu tworzyw sztucznych.
EN
Plastics are long chain synthetic polymers produced based on fossil fuels such as oil and natural gas. Due to their properties, like lightness, durability, strength, flexibility, and low production costs, they have become indispensable in everyday life. Every year, the amount of polymers produced increases, in 2020 only in Europe 49.1 million tonnes of polymers were produced. With the increasing production of plastics and their widespread use, a global problem with the accumulation of waste in the natural environment has arisen. In Europe, synthetic waste is mostly incinerated (42.6%) and recycled (34.6%). In the natural environment, plastics can be degraded both by abiotic processes and by biodegradation (Fig.5.). The susceptibility to degradation of polymers depends on their physicochemical properties, the length of the polymer chain, and their composition. Long-chain polymers containing only carbon, such as polyethylene and polypropylene, are more resistant to degradation, while in the case of polyurethane and polyethylene terephthalate, the presence of heteroatoms in the chain, e.g. oxygen, causes greater susceptibility to biodegradation. The appearance of polymer waste in the natural environment caused many microorganisms to develop the ability to use plastics as a source of carbon and energy. The evolution of the metabolic systems of cells, which allows obtaining nutrients from polymers, somehow adapts microbes to live in the era of synthetic materials. Microorganisms equipped with the ability to degrade plastic have been characterized in many scientific studies (Tab. 2). The biodegradation of plastics is a complex process that depends on several factors: substrate availability, surface characteristics, morphology, and molecular weight. The first stage of biodegradation is the deposition of microorganisms on the surface of the polymer, which is largely influenced by the hydrophobicity / hydrophilicity of the material. Microorganisms then produce specific extracellular enzymes that break down the main polymer chain into smaller fragments – dimers and monomers. Then the polymer molecules are transported inside the cell and the final products of polymer decomposition are water, CO2, and biomass. Plastics are characterized by high durability and resistance to biodegradation, therefore pre-aging or pre-treatment of synthetic materials is often necessary. The purpose of these treatments is to modify the surface, which increases susceptibility to the action of enzymes secreted by microorganisms. The most commonly used pre-treatment techniques are UV, gamma, high temperature, and nitric acid treatment. These techniques either reduce hydrophobicity or introduce more biodegradable groups on the surface of the polymer. Describing the process of biodegradation of plastics is a technical challenge because it is a long-term process and difficult to study. The most commonly used methods of assessing the biodegradation of a polymer are the examination of the amount of mass lost by polymers, the examination of hydrophobicity and surface changes by imaging techniques such as SEM, and the chemical composition of polymers using Fourier transform infrared spectroscopy.
EN
Ballast water is a significant vector for the transport and introduction of aquatic organisms, microorganisms and chemical pollutants which impacts on ecosystems worldwide. In the study, ballast water from short- and long- range vessels with treatment systems was microbiologically evaluated in spring (April 20th) and summer (July 19th) and compared with waters of the main Police Seaport in the Odra River Estuary, southern Baltic Sea. All collected samples were evaluated for their physicochemical properties by standard methods. The number of individual groups of microorganisms was determined using the indirect culture method, according to the technique of inoculation of serial dilutions of samples of the examined waters. The results showed differences in the microorganisms in analysed samples. The phylogenetic analysis of bacteria recorded from the ballast water of short-range ships in spring showed the presence of six species of the genus Bordetella, while in summer four species of the genus Clostridium. In the ballast water of long-range ships, proteolytic bacteria pre-dominated in spring and halophilic bacteria in summer. In the summer period, eight species of bacteria were recorded, of which six belonged to the genus Clostridium. The ballast water treatment processes used on ships influence the composition of bacterial communities through selective recolonisation of water, which may transform bacterial functions as an important element of the marine food web. On the other hand, the presence of pathogenic bacterial species in the tested samples indicates improvement necessity of ballast water treatment systems used on vessels.
EN
The role of fibrous carrer in the formation of microbiocenosis, which provides purification of aquatic environments, was studied. The prospects of using the "Vija" fibrous carrer for cleaning the watercourses of mountainous areas were studied. The species composition, as well as the kinetics of periphyton formation on fibrous carrer, were established. The species composition of the microbiocenosis, which is formed on carrer in the mode of active aeration of landfill filtrates and the prospects of using the method of aerated lagoon for filtrate treatment were studied.
PL
W artykule omówiono metody wykorzystywane w biodegradacji wielopierścieniowych węglowodorów aromatycznych występujących w osadach czynnych i dennych. Przeanalizowano ich skuteczność i wpływ na oczyszczanie środowiska z zanieczyszczeń WWA.
EN
The article discusses the methods used in the biodegradation of polycyclic aromatic hydrocarbons found in active and bottom sediments. Their effectiveness and influence on the purification of the environment from PAH pollution were analyzed.
PL
Biowodór powstaje w wyniku aktywności metabolicznej mikroorganizmów w warunkach beztlenowych. W artykule omówiono szlaki metaboliczne produkcji biowodoru: biofotolizę, fotofermentację i ciemne fermentacje. Szczególny nacisk położono na procesy produkcji biowodoru na etapie kwasogenezy beztlenowego rozkładu biomasy (ciemna fermentacja i konwersja mleczanu i octanu do maślanu) jako obiecującą metodę produkcji biowodoru. Produkcja biowodoru taką metodą charakteryzuje się niską wydajnością i wymaga ograniczenia procesów konkurencyjnych, głównie innych typów fermentacji kwaśnych. Produkcja biowodoru na etapie kwasogenezy jest możliwa w instalacjach dwu - lub wieloetapowych, w których etap kwasogenezy jest oddzielony czasowo i przestrzennie od etapów acetogenezy i metanogenezy. Przedstawiono prace nad tego typu technologią na przykładzie dwuetapowej instalacji produkcji biowodoru i biometanu na drodze beztlenowego rozkładu produktów ubocznych przemysłu cukrowniczego opracowanej w jednostce naukowej i rozwijanej przez partnera przemysłowego. Omówiono wyzwania i ograniczenia produkcji biowodoru, zwłaszcza na etapie kwasogenezy. Zdefiniowano powody niedojrzałości technologii produkcji biowodoru i pozostawanie ich ciągle na etapie badawczo-rozwojowym w porównaniu do zaawansowanych, wdrażanych rozwiązań produkcji biogazu.
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Biohydrogen is produced by the metabolic activity of microorganisms under anaerobic conditions. The article discusses the metabolic pathways of biohydrogen production: biophotolysis, photo-fermentation, and dark fermentations. Special emphasis was put on biohydrogen production processes at the acidogenesis stage of anaerobic digestion (dark fermentation and conversion of lactate and acetate to butyrate) as a promising method of biohydrogen production. The production of biohydrogen by such a method has low yields and requires the reduction of competing processes, mainly other types of acid fermentation. Production of biohydrogen at the acidogenesis stage is possible in two-stage or multi-stage systems, in which the acidogenesis stage is separated in time and space from the acetogenesis and methanogenesis stages. The work on such a technology is presented using the example of a two-stage installation for the production of biohydrogen and biomethane by anaerobic digestion of sugar industry by-products developed at a research unit and being developed by an industrial partner. Challenges and limitations of biohydrogen production were discussed, especially at the acidogenesis stage. Reasons for the immaturity of biohydrogen production technologies and their still remaining in the research and development stage compared to advanced, implemented biogas production solutions were discussed.
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Leather products provide an ideal environment for microbial growth. In order to prevent the appearance and spread of various types of microorganisms, it is treated with selected biocides and even essential oils. The aim of this paper was to investigate the antifungal activity of selected essential oils applied to finished chromium tanned leather which is intended for leather fancy products. Antifungal activity was evaluated according to the PN-EN 14119: 2005 standard. Four finished chromium tanned leathers were tested, each of which was soaked in the following essential oils: tea tree essential oil at a concentration of 1, 2 and 5% and thyme essential oil at concentration of 1, 2 and 5%. The results obtained indicated that leather finishing with thyme essential oil showed the antimicrobial activity against Aspergillus niger, Chaetomium globosum and Candida albicans strains. The application of 5% thyme essential oil to leather samples inhibited the growth of all strains tested. Using tea tree essential oil on leather samples showed a antimicrobial effect only against Candida albicans. The application of essential oils in the leather finishing process may be an alternative to biocides used in the tanning industry.
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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.
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A microbiological analysis of indoor air quality in offices, lecture rooms, and hallways in a public utility building has been carried out in the Lubuskie Voivodship (Poland). In one of the storage rooms, the presence of fungi on the building partition was found in the place of water infiltration as a result of a technological failure in the building. A total of 17 nonresidential interiors were examined. The total number of psychrophilic and mesophilic bacteria and the total number of fungi were sampled by the collision method with the air sampler. A qualitative analysis has been performed of fungi present in the indoor air and from building partition of the studied interiors. A total of 11 species of fungi have been specified. Relative humidity and air temperature were measured with a hygrometer. The studies showed that the number of psychrophilic bacteria in indoor air was in the range 0-730 CFU/m3 , while the number of mesophilic bacteria was slightly higher (0-896 CFU/m3 ). A high level of contamination and a large number of fungi (734 CFU/m3 ) were found in the indoor air of storage room, where the problem of biodeterioration of building partitions occurred. In the remaining rooms, the level of microorganisms was low or moderate. Microbiological tests of the outdoor air (background) did not reveal an excessive number of microorganisms in the air.
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