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Occurrence of antimicrobial resistant bacteria in environment and the statistical analysis of this phenomenon
PublicationIntroduction: In this study the occurrence of antimicrobial resistance patterns among fecal indicators (Escherichia coli and Enterococcus spp.) was analyzed in water and wastewater samples. The trends in antimicrobial resistance were analyzed using basic statistical methods. Methods: Samples were obtained from two local watercourses (Oliwski Stream and Reda River) as well as from the wastewater treatment plant (WWTP) Gdansk - Wschod....
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Presence and distribution of antibiotic-resistant bacteria in multiphase activated sludge system
PublicationIn total 237 isolates of coliforms (113 strains) and enterococci (124 stains) from influent, mixed liquor in bioreactor and effluent of wastewater treatment plant (WWTP), were isolated on selective media and examined for antibiotic resistance. From 50 to 80% of the coliform strains isolated from the raw and treated sewage were resistant against ceftazidime CAZ, cefuroxim CXM, cefalotin KF and against amoxicillin AML, and only below...
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Amino Acid Based Antimicrobial Agents – Synthesis and Properties
PublicationStructures of several dozen of known antibacterial, antifungal or antiprotozoal agents are based on the amino acid scaffold. In most of them, the amino acid skeleton is of a crucial importance for their antimicrobial activity, since very often they are structural analogs of amino acid intermediates of different microbial biosynthetic pathways. Particularly, some aminophosphonate or aminoboronate analogs of protein amino acids are...
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The occurrence of heavy metals and metal-resistant bacteria in water and bottom sediments of the Straszyn reservoir (Poland)
PublicationThe aim of this study is investigate the distribution of selected heavy metals (zinc, copper, lead, cadmium) and metal-resistant bacteria in water and bottom sediments of drinking water reservoir for Gdańsk (Poland). The research area - Straszyn Lake is a dam reservoir on Radunia river, of the total volume of 3 mln m3. Sediment and water sampling took place between May and October 2013 (eight series). Regarding metal concentration...
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Anaerobic bacteria in wastewater treatment plant
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TOLERANCE OF ENVIRONMENTAL BACTERIA TO HEAVY METALS
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Dissociative electron attachment to benzoic acid (C7H6O2)
PublicationThe dissociative electron attachment (DEA) to benzoic acid (C6H5COOH) has been studied using an experimental crossed beam setup of a quadrupole mass spectrometer and a trochoidal electron monochromator. Relative partial cross sections for the DEA to produce negative ion fragments show the main channels for dissociation. The comparison of the present results with the ultraviolet photoelectron spectrum of benzoic acid [J. Meeks,...
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Human-associated bacteria and their mobile genetic elements - important minority in wastewater and wastewater impacted ecosystems
PublicationSince human-associated bacteria have been recognized as vectors in two - way gene transmission between the pathogenic and environmental populations, health hazard connected with wastewater discharge requires reevaluation. In this paper the particular attention was given to antimicrobial-resistance of Escherichia coli and enterococci isolated from wastewater and wastewater impacted environments. The obtained results showed that...
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Role of size scale of ZnO nanoparticles and microparticles on toxicity toward bacteria and osteoblast cancer cells
PublicationThe specific role of size scale, surface capping, and aspect ratio of zinc oxide (ZnO) particles on toxicity toward prokaryotic and eukaryotic cells was investigated. ZnO nano and microparticles of controlled size and mor- phology were synthesized by wet chemical methods. Cytotoxicity toward mammalian cells was studied using a human osteoblast cancer cell line and antibacterial activity using Gram-negative bacteria (Escherichia...
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Removal of indicator bacteria from treated wastewater using physical and chemical methods. Pilot plant study.
PublicationEven after highly efficient biological processes the effluents from wastewater treatment plants may contain significant number of fecal bacteria, from 104 to 106 CFU/100 mL. Since no standards are set on the bacteriological quality of treated wastewater in Poland the elimination of bacterial contaminants is not a priority in wastewater treatment policy. Thus microbiological hazards become particularly significant in the situation...
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The Antimicrobial Potential of Bacteria Isolated from Honey Samples Produced in the Apiaries Located in Pomeranian Voivodeship in Northern Poland
PublicationThe principal objective of this study was to determine whether the honeys produced in apiaries located in Pomeranian Voivodeship (Northern Poland) contain bacteria producing metabolites with growth inhibition potential against important human and animal pathogens. The pathogens included Staphylococcus aurues, Staphyloccocus epidermidis, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, and Candida albicans. From...
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Long-Period Gratings and Microcavity In-Line Mach Zehnder Interferometers as Highly Sensitive Optical Fiber Platforms for Bacteria Sensing
PublicationSelected optical fiber sensors offer extraordinary sensitivity to changes in external refractive (RI), which make them promising for label-free biosensing. In this work the most sensitive ones, namely long-period gratings working at (DTP-LPG) and micro-cavity in-line Mach-Zehnder interferometers (µIMZI) are discussed for application in bacteria sensing. We describe their working principles and RI sensitivity when operating in water...
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Amino Acid and Peptide‐Based Antiviral Agents
PublicationA significant number of antiviral agents used in clinical practice are amino acids, short peptides, or peptidomimetics. Among them, several HIV protease inhibitors (e. g. lopinavir, atazanavir), HCV protease inhibitors (e. g. grazoprevir, glecaprevir), and HCV NS5A protein inhibitors have contributed to a significant decrease in mortality from AIDS and hepatitis. However, there is an ongoing need for the discovery of new antiviral...
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Culturable bacteria community development in postglacial soils of Ecology Glacier, King George Island, Antarctica
PublicationGlacier forelands are excellent sites in which to study microbial succession because conditions change rapidly in the emerging soil. Development of the bacterial community was studied along two transects on lateral moraines of Ecology Glacier, King George Island, by culture-dependent and culture-independent approaches (denaturating gradient gel electrophoresis). Environmental conditions such as cryoturbation and soil composition...
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Microwave-assisted preparation of potato starch silicated with silicic acid
PublicationApplication of microwave irradiation for the silication of granular potato starch with silicic acid, and the properties of silicated starch were investigated. Potato starch was esterified on 20 min microwave irradiation of starch with silicic acid, applying the power of 450 or 800Wand, for comparison, on 120 min convectional heating of the reagent blend at 100 ◦C. The degree of esterification and the reaction efficiency did not...
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Beeswax And Palmitic Acid Utilization With Heat Pipes For Electronics Cooling
PublicationThis paper presents an experimental study of heat pipes supported by phase change materials (PCMs) coated at their adiabatic sections in application for electronics cooling. The PCMs investigated in this research were palmitic acid and beeswax, the latter being considered as a more cost-effective alternative. The study focused on three powers: 20W, 25W, and 30W. The experimental results revealed that the incorporation of palmitic...
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New conjugates of mycophenolic acid and their antiproliferative activity
PublicationThe new conjugates of mycophenolic acid (MPA) were obtained in the reaction of N6-(ω-aminoalkyl)adenosines with MPA in the presence of EDCI as a coupling reagent. New compounds 4a–h were evaluated on leukemia cell line (Jurkat) and PBMC from healthy donors. Length of the linker influenced observed activity. The compound 4b possessing 1,3-diamine spacer exhibited the most promising results and can be considered to further investigations.
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Preliminary Investigation on Rapid Potassium Efflux from Activated Sludge in Response to Use of Peroxyacetic Acid
PublicationPreliminary research on activated sludge potassium efflux (GGKE - glutathione-gated potassium efflux) as a result of peroxyacetic acid (PAA) dosing were performed. Similarily as in case of chlorine dosing the PAA dosing causes initiation of bacteria defense mechanisms, related to the transformations of glutathione tripeptide, resulting in the increase of potassium ions concentration in the activated sludge environment. In the range...
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Thermal and mechanical properties of polyurethanes modified with L-ascorbic acid
PublicationIn this study we report the thermal and mechanical properties of polyurethanes modified with ascorbic acid (AA). Ascorbic acid was used as a modifier at concentration of 1 or 2 mass%. The antioxidative properties of AA may improve the biocompatibility of the obtained materials, which were designed for biomedical applications. In this paper we describe characterization of obtained unmodified and ascorbic acid modified polyurethanes...
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Characterization of single-stranded DNA-binding proteins from the psychrophilic bacteria Desulfotalea psychrophila, Flavobacterium psychrophilum, Psychrobacter arcticus, Psychrobacter cryohalolentis, Psychromonas ingrahamii, Psychroflexus torquis, and Photobacterium profundum
PublicationBackground: Single-stranded DNA-binding proteins (SSBs) play essential roles in DNA replication, recombination and repair in Bacteria, Archaea and Eukarya. In recent years, there has been an increasing interest in SSBs, since they find numerous applications in diverse molecular biology and analytical methods. Results: We report the characterization of single-stranded DNA-binding proteins from the psychrophilic bacteria Desulfotalea...
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Physical crosslinking of hyaluronic acid in the presence of phospholipids in an aqueous nano-environment
PublicationHyaluronic acid and phospholipids are two components in the synovial joint cavity that contribute to joint lubrication synergistically. Molecular dynamics simulations were performed and hydrogen bonds in hyaluronic acid were analyzed to identify specific sites that are responsible for its physical cross-linking. Two molecular masses of hyaluronic acid, 10 kDa and 160 kDa, were considered. We use molecular dynamics simulations and...
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The Role of Proteases in the Virulence of Plant Pathogenic Bacteria
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Cytotoxic and Antioxidant Activities of Benzohydroxamic Acid Analogues
Publication20 benzohydroxamic acid analogues were synthesized and evaluated for their in vitro cytotoxicities against mouse mammary tumor cells as well as antioxidant activities against DPPH radical and superoxide anion. It was found that benzothiohydroxamic acids exhibit greater cytotoxicities than benzohydroxamic acids and N-isopropyl derivatives are more active than N-methyl ones. On the other hand, benzothiohydroxamic acids show more...
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Maternal smoking Modulates Fatty Acid Profile of Breast Milk
PublicationAIM: We hypothesized that the fatty acid composition of breast milk can be affected by a smoking habit in the mother. Consequently, this study verified whether maternal smoking modulates, and if so to what extent, the breast milk fatty acid profile. METHODS: The study included 20 postpartum women who declared smoking more than five cigarettes daily throughout a period of pregnancy and lactation, and 136 non-smoking postpartum women....
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Sulfate‐reducing bacteria‐assisted hydrogen‐induced stress cracking of 2205 duplex stainless steels
PublicationThe paper presents the results of a laboratory investigation of the microbiologically assisted hydrogen‐induced stress cracking (HISC) of 2,205 duplex stainless steel (DSS). The testing of susceptibility toward HISC was performed with two different methods. Precharged in sulfate‐reducing bacteria (SRB), inoculated medium samples were subjected to slow strain‐rate testing in artificial seawater. In situ constant load tests were...
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An Improved Synthesis of Trisodium (R)-Homocitrate from Citric Acid
PublicationA method of synthesis of trisodium (R)-homocitrate starting from citric acid is reported. The procedure affords the final product of high optical purity with satisfactory yield.
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Molecular targets for antifungals in amino acid and protein biosynthetic pathways
PublicationFungi cause death of over 1.5 million people every year, while cutaneous mycoses are among the most common infections in the world. Mycoses vary greatly in severity, there are long-term skin (ringworm), nail or hair infections (tinea capitis), recurrent like vaginal candidiasis or severe, life-threatening systemic, multiorgan infections. In the last few years, increasing importance is attached to the health and economic problems...
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Acyl Meldrum's acid derivatives: application in organic synthesis
PublicationThis review is focused on one of the most important classes of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleiophiles. The possible mechanisms of these transformations...
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The coexistence and competition of canonical and comammox nitrite oxidizing bacteria in a nitrifying activated sludge system – Experimental observations and simulation studies
PublicationThe second step of nitrification can be mediated by nitrite oxidizing bacteria (NOB), i.e. Nitrospira and Nitrobacter, with different characteristics in terms of the r/K theory. In this study, an activated sludge model was developed to account for competition between two groups of canonical NOB and comammox bacteria. Heterotrophic denitrification on soluble microbial products was also incorporated into the model. Four 5-week washout...
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Release of potassium from actvated sludge as a resultof use peroxyacetic acid = Uwalnianie potasu z osadu czynnego pod wpływem kwasu nadoctowego
PublicationThe phenomenon of potassium efflux (GGKE - glutathione-gated potassium efflux) from the calls of activated sludge bacteria in the result of peroxyacetic acid (CH3CO3H) dosing was investigated. Addition of the strong oxidant to the activated sludge environment caused activation of the defense mechanisms of bacterial cells, related to glutathione transformations, which resulted in the significant increase of potassium ions concentration....
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Dissociation of 2-oxopropanoic acid by low energy electrons
PublicationElectron attachment to molecular target can lead to a variety of negative fragment ions. We experimentally probe the main dissociative electron attachment (DEA) channels in 2-oxopropanoic acid (CH3 - CO - COOH) - an important trace component in the Earth's atmosphere. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV.
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Electron attachment and electron iozization of acetic acid clusters embedded in helium nanodroplets
PublicationThe effect of incident electrons on acetic acid clusters is explored for the first time. The acetic acid clusters are formed inside liquid helium nanodroplets and both cationic and anionic productsejected in to the gas phase aredetected by mass spectrometry.
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ASCORBIC ACID IN POLYURETHANE SYSTEMS FOR TISSUE ENGINEERING
PublicationThe introduction of the paper was devoted to the main items of tissue engineering (TE) and the way of porous structure obtaining as scaffolds. Furthermore, the significant role of the scaffold design in TE was described. It was shown, that properly designed polyurethanes (PURs) find application in TE due to the proper physicochemical, mechanical and biological properties. Then the use of L-ascorbic acid (L-AA) in PUR systems for...
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A Novel Cryptic Clostridial Peptide That Kills Bacteria by a Cell Membrane Permeabilization Mechanism
PublicationThis work reports detailed characteristics of the antimicrobial peptide Intestinalin (P30), which is derived from the LysC enzyme of Clostridium intestinale strain URNW. The peptide shows a broader antibacterial spectrum than the parental enzyme, showing potent antimicrobial activity against clinical strains of Gram-positive staphylococci and Gram-negative pathogens and causing between 3.04 ± 0.12 log kill for Pseudomonas aeruginosa...
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Interaction of low energy electrons with formic acid monomer, dimer and trimer
PublicationConfigurations of the formic acid monomer, dimer and trimer are presented. We have calculated the total energies for these structures. We have considered also the negatively charged clusters and discussed the possible pathways of interaction of low energy electrons with monomers and clusters. Calculations have been executed using 6-311G** and 6-311++G** basis sets. The electron affinities of monomer and clusters are presented....
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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
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Occupational exposure to anaerobic bacteria in a waste sorting plant
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Probiotic Bacteria: A Promising Tool in Cancer Prevention and Therapy
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Biodegradation of nodularin and other nonribosomal peptides by the Baltic bacteria
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Factors Determining the Susceptibility of Bacteria to Antibacterial Photodynamic Inactivation
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Effect of high pressure of selected bacteria at subzero temperature
PublicationCelem pracy było określenie przeżywalności wybranych bakterii gramdodatnich i gramujemnych poddanych działaniu podwyższonego ciśnienia w zakresie od 60 do 193 MPa w ujemnej temperaturze. Wrażliwość bakterii na zwiększone ciśnienie zależy od fazy wzrostu w jakiej się one znajdują. Z reguły bakterie gramdodatnie są bardziej odporne na ciśnienie niż bakterie gramujemne. Wykazano, że różnice w odporności pojawiają się nie tylko pomiędzy...
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The application of ultrafiltration for separation of glycerol solution fermented by bacteria
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Culturable bacteria from pesticides contaminated soils in Poland
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Defining the Genetic Basis of Plant–Endophytic Bacteria Interactions
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Sulphate reducing bacteria in groundwater intakes in Gdańsk Region.
PublicationPraca przedstawia wyniki badań określające występowanie bakterii redukujących siarczany w wodach podziemnych ujmowanych z utworów kredowych oraz z utworów czwartorzędowych w regionie gdańskim. Bakterie te okresowo znajdują odpowiednie warunki do wzrostu w środowisku wód podziemnych i w wyniku procesów metabolizmu produkują siarkowodór pogarszający cechy organoleptyczne wody. W celu ograniczenia niekorzystnych zmian jakości wody...
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CROSS SECTIONS CALCULATIONS FOR ELECTRON SCATTERING FROM RHODANINE AND CYANOACETIC ACID
PublicationCross sections for electron-impact ionization and for elastic electron scattering for rhodanine (C3H3NOS2) and cyanoacetic acid (C3H3NO2) have been calculated in wide impinging electron energy range.
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Occurrence and properties of sulphate reducing bacteria in groundwater in Gdańsk region; Selected methods of elimination.Bakterie redukujące siarczany na ujęciach wód podziemnych w regionie gdańskim.
PublicationGdańsk region is situated in the area with good hydrogeological conditions. The ground-water designed for drinking purposes is taken mainly from the Quaternary and addition-ally from Cretaceous aquifers. The urban development and intensive take off have caused the increase of water exploitation and as a consequence of the changes of hydrogeological conditions the deterioration of chemical and bacteriological quality of water has...
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
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Thermal energy storage using stearic acid as PCM material
PublicationThis work presents an experimental study of thermal energy storage by use of PCM. The aim of the study was to establish the influence of different inlet temperature of heat transfer fluid (HTF) and different Reynolds number of HTF on intensity of charging process. The PCM used in this study was stearic acid and water was used as HTF. A copper helical coil mounted in cylindrical container served as a heat transfer surface.
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Identification and characterization of single-stranded DNA-binding protein from the facultative psychrophilic bacteria Pseudoalteromonas haloplanktis
PublicationSingle-stranded DNA-binding protein (SSB) plays an important role in DNA metabolism such as DNAreplication, repair, and recombination, and is essential for cell survival. This study reports on the ssb-likegene cloning, gene expression and characterization of a single-stranded DNA-binding protein of Pseudoal-teromonas haloplanktis (PhaSSB) and is the first report of such a protein from psychrophilic microorganism.PhaSSB possesses...