Facilitation of co-metabolic transformation and degradation of monochlorophenols by Pseudomonas sp. CF600 and changes in its fatty acid composition

In this study, co-metabolic degradation of monochlorophenols (2-CP, 3-CP, and 4-CP) by the Pseudomonas sp. CF600 strain in the presence of phenol, sodium benzoate, and 4-hydroxybenzoic acid as an additional carbon source as well as the survival of bacteria were investigated. Moreover, the changes in cellular fatty acid profiles of bacteria depending on co-metabolic conditions were analyzed. It was found that bacteria were capable of degrading 4-CP completely in the presence of phenol, and in the presence of all substrates, they degraded 2-CP and 3-CP partially. The highest 2-CP and 3-CP removal was observed in the presence of sodium benzoate. Bacteria exhibited three various dioxygenases depending on the type of growth substrate. It was also demonstrated that bacteria exposed to aromatic growth substrates earlier degraded monochlorophenols more effectively than unexposed cells. The analysis of fatty acid profiles of bacteria indicated the essential changes in their composition, involving alterations in fatty acid saturation, hydroxylation, and cyclopropane ring formation. The most significant change in bacteria exposed to sodium benzoate and degrading monochlophenols was the appearance of branched fatty acids. The knowledge from this study indicates that Pseudomonas sp. CF600 could be a suitable candidate for the bioaugmentation of environments contaminated with phenolic compounds

Still Seeking for Something : The Unspeakable (Loss) in Passing by Nella Larsen

The paper analyzes Nella Larsen’s Passing (1929) through the lens of the theory of melancholy from Freud to Butler. Examining the dynamic relationship between Irene Redfield and Clare Kendry, two protagonists of Larsen’s novella, I attempt to demonstrate that under the surface of clearly expressed racial tensions, focused upon the dilemma of passing, there is a more deeply hidden problem - the one of gender identity and sexual desire

Changes in fatty acid composition of Stenotrophomonas maltophilia KB2 during co-metabolic degradation of monochlorophenols

The changes in the cellular fatty acid composition of Stenotrophomonas maltophilia KB2 during cometabolic degradation of monochlorophenols in the presence of phenol as well as its adaptive mechanisms to these compounds were studied. It was found that bacteria were capable of degrading 4-chlorophenol (4-CP) completely in the presence of phenol, while 2-chlorophenol (2-CP) and 3-chlorophenol (3-CP) they degraded partially. The analysis of the fatty acid profiles indicated that adaptive mechanisms of bacteria depended on earlier exposure to phenol, which isomer they degraded, and on incubation time. In bacteria unexposed to phenol the permeability and structure of their membranes could be modified through the increase of hydroxylated and cyclopropane fatty acids, and straight-chain and hydroxylated fatty acids under 2-CP, 3-CP and 4-CP exposure, respectively. In the exposed cells, regardless of the isomer they degraded, the most important changes were connected with the increase of the contribution of branched fatty acid on day 4 and the content of hydroxylated fatty acids on day 7. The changes, particularly in the proportion of branched fatty acids, could be a good indicator for assessing the progress of the degradation of monochlorophenols by S. maltophilia KB2. In comparison, in phenol-degrading cells the increase of cyclopropane and straight-chain fatty acid content was established. These findings indicated the degradative potential of the tested strain towards the co-metabolic degradation of persistent chlorophenols, and extended the current knowledge about the adaptive mechanisms of these bacteria to such chemicals

Transformation and ecotoxicological effects of iodinated X-ray contrast media

Iodinated X-ray contrast media (ICM) such as diatrizoate, iohexol, iomeprol, iopamidol, and iopromide are commonly used in medical imaging for radiological visualization of a variety of anatomic structures. Because of their highly persistent nature and poor removal by conventional wastewater treatment, ICM can often remain unchanged after entering the environment or they are transformed into many different by-products in complex physical, chemical, and biological processes. Large amounts of ICM and their by-products are found in natural waters, groundwater, drinking water (up to 100 lg/L), and even in soil, where they can be a potential threat to the inhabitants of these environments. Because knowledge about the fate of ICM in various environments is dispersed and it concerns specific areas, the main purpose of this review is to summarize the available information about their occurrence, chemical and biological transformation/degradation, and toxicity to living organisms. The topics discussed particularly focus on mechanisms of ICM degradation/transformation in water using advanced oxidation processes and the biotransformation/biodegradation of ICM by microorganisms under different conditions, as well as the toxicity of ICM and their transformation byproducts to humans and other organisms. Although environmental risk is not expected from the parent compounds of ICM, their continuous input to the water and the formation of toxic by-products may constitute a long-term potential risk for living organisms. Therefore, monitoring the transport and fate of ICM in various environments seems necessary

„Komuniści (nie) mają ojczyzny...” Wanda Wasilewska jako polska (anty)bohaterka narodowa

Communists have no homeland: a portrait of Wanda Wasilewska  The paper offers an analysis of a number of biographies of Wanda Wasilewska, written in different historical periods. An attempt was made to reconstruct the mechanisms that governed the functioning of Wanda Wasilewska’s communist figure in the Polish political discourse; explain how she was perceived by the society, and how it altered in the course of the Polish cultural and historical transformations. A biography of an individual gains coherence as a result of the community’s search for its identity: it serves as a building block for a coherent biography of the entire community. The writing and rewriting of the biography of Wasilewska has long been a kind of “production of communism” in Poland, and communism has been one of the most important aspects of Polish identity in the recent decades.   „Komuniści (nie) mają ojczyzny...” Wanda Wasilewska jako polska (anty)bohaterka narodowa Autorka analizuje powstające w rożnych okresach historycznych biografie Wandy Wasilewskiej. Usiłuje odtworzyć mechanizmy konstruowania figury komunistki w polskim dyskursie publicznym, zbadać, jak funkcjonowała ona w społecznym odbiorze, a także ustalić, jak zmieniało się jej znaczenie w procesie przemian historycznych i kulturowych. Autorka pokazuje, że tworzenie spójnej biografii jednostki – szczególnie jednostki ważnej w historii danej zbiorowości – dokonuje się w odpowiedzi na tożsamościowe poszukiwania wspólnoty: służy wytworzeniu zbiorowej biografii jako koherentnej całości. Zwraca uwagę, że pisanie biografii Wasilewskiej jako komunistki było i wciąż jest swoistym „wytwarzaniem komunizmu” w Polsce. Komunizm zaś w szerokim planie jest ważnym – jeśli nie najważniejszym w ostatnich dziesięcioleciach – komponentem polskiej zbiorowej tożsamości

Microbial action in wastewater and sludge

This Special Issue provides valuable results and new views on the topic of pollutant removal from wastewater and landfill leachate based on various remediation approaches and literature data, including important key challenges and limitations. The novelties worth emphasizing are: the proposition of ideal candidates for bioaugmentation of activated sludge fed with phenolic leachate; the isolation and identification of new diclofenac-degrading strains; the first use of active biomass and stress biomass indices to assess the impact of leachate and bioaugmentation on AS performance; the use of Ascomycete Lambertella sp. in the depletion of the recalcitrant to biodegradation loads of intermediate and old leachate; as well as an interesting presentation of scientific views on pollutant biosorption using fungal pellets. All authors also emphasized the need for further research and indicated future study directions

Zmiany w składzie bakteryjnych kwasów tłuszczowych w czasie rozkładu fenolu w glebie

The aim of this study was to investigate the effects of phenol on fatty acid composition of Pseudomonas vesicularis and Pseudomonas sp. JS150 strains introduced into sterile L1, L2 and G soils and in Pseudomonas- inoculated non-sterile soils. Phenol was added to all soils at the concentration of 1.7 mg g–1, 3.3 mg g–1 and 5.0 mg g–1. Simultaneously, the survival of both strains introduced into soils was estimated. The investigations were conducted in four separate experimental arrangements. The first comprised sterile soils with introduced Pseudomonas vesicularis strain, the second — sterile soils with Pseudomonas sp. JS150, the third-sterile soils containing the mixture of these strains and the fourth — Pseudomonas-inoculated non-sterile soils. FAMEs extracted from these soils at the following sampling days were analysed by GC method and identified using software Sherlock, 3,90. It was found that phenol degradation by Pseudomonas vesicularis or/and Pseudomonas sp. JS150 depended on type of soil, phenol contamination and inoculum composition. The highest phenol removal at each concentration in L1, L2 and G soils was observed when bacteria were used as a mixture, phenol was metabolized slower by Pseudomonas sp. JS150 and much slower by Pseudomonas vesicularis. It was also demonstrated that independently on inoculum composition phenol degradation rate varied depending on type of soil. In G soil with the highest amount of organic matter phenol degradation proceeded faster than in L1 soil with intermediate amount of organic matter and in L2 soil with the lowest amount of organic matter. Obtained results also indicated that increasing dose of phenol made its biodegradation much longer. On the basis of bacterial counts it was showed that Pseudomonas sp. JS150 strain better survived both in phenol-polluted and the unpolluted soils in comparison with Pseudomonas vesicularis. Bioaugmentation with Pseudomonas vesicularis and Pseudomonas sp. JS150 strain in all soils resulted in the increase of effectiveness of phenol removal as compared to control samples. It indicated that the interactions between autochtonous bacteria and strains introduced into soils were synergic. The analyses of fatty acid percentages and composition in bacterial cells showed that they regulated of membrane fluidity and permeability in response to actual phenol concentration in soil. The first reaction of both strains in the presence of phenol added was de novo synthesis and changes in composition of saturated, straight-chain and branched fatty acids at the beginning days of experiment. While the phenol concentration decreased above 50% of dose used cyclopropane fatty acid 19:0 cy ω10c from these cells was isolated. In turn, the abundance of hydroxy fatty acids in that time decreased or they were not present in FAMEs profiles. The ratio of saturated/unsaturated fatty acids appeared the useful marker for rate of phenol degradation by Pseudomonas vesicularis or/and Pseudomonas sp. JS150. At the first days of experiment when phenol concentration in soils was high saturated/unsaturated ratio increased. It highest value was calculated generally at day when the abundance of 19:0 cy ω10c fatty acid was the highest whereas at the following days simultaneously with phenol removal it decreased. The value of sat/unsat ratio varied in response to the type of soil, inoculum composition and dose of phenol added. The similar correlations between phenol concentration, the presence of 19:0 cy ω10c fatty acid and value of sat/unsat ratio were observed in phenol amended and Pseudomonas-inoculated soils and phenol amended but not-inoculated soils. The abundance of saturated, straight-chain and branched fatty acids changed also in these soils but the changes were significantly lower as compared to sterile soils with introduced of Pseudomonas vesicularis or/and Pseudomonas sp. JS150 strains. In turn, the amount of hydroxy fatty acids isolated from these soils remained at the similar level. It indicates that adaptive mechanisms to the presence of phenol were similar both in laboratory selective of Pseudomonas vesicularis and Pseudomonas sp. JS150 strains and in other species of bacteria naturally existing in soil. It was confirmed that MIDI-FAME method could be used to monitor the progress of phenol elimination from soil. On the basis of fatty acid profiles and analysis of value of sat/unsat ratio it is possible to estimate if degradation of phenol by microorganisms in soil proceeds and the presence and abundance of 19:0 cy ω10c fatty acid indicate the progress of this process. For this reason, they may be good biomarkers of phenol contaminated environments

Materijalno-energetski model životnog ciklusa motornog vozila

Nowadays one of the most important elements of economic and social lives is motorization. Its development is most of all accompanied by increasing the use of various means of transport, especially motor vehicles. Such a significant increase in the amount of vehicles produced can be implemented by the global use of productive materials and energy carriers, which is increasingly higher each year. Operating a higher number of vehicles causes an increase in environment pollution, not only by deleterious substance emissions, being the effect of fuel combustion, or implementation of production processes in the automotive industry, but also by a growing amount of exchanged parts and sub-assemblies and, mostly, by the rapid growth of vehicles that are withdrawn from traffic and subjected to car breaking. The article presents a material-energy model of a motor car life cycle that can be helpful in determining the type and size of the expenditure of material and energy as well as emission loading in particular phases and the whole life cycle of a vehicle. Based on the input data contained in [9] analysis of the results of calculations related to examples of the material structure of the model vehicle from 1990 and 2000 and the impact of these changes on energy consumption and emission levels were presented.Jedan od najvažnijih elemenata ekonomskog i društvenog života u današnje vrijeme je motorizacija. Njen razvoj je u najvećoj mjeri popraćen povećanim uporabom prijevoznih sredstava, posebice motornih vozila. Takvo značajno povećanje količine proizvedenih vozila provodi se zbog globalne uporabe proizvodnih materijala i nositelja energije iz godine u godinu je sve veća i veća. Veći broj vozila u pogonu povećava zagađenje okoliša, ne samo emisijama štetnih tvari u okoliš, koje su posljedica izgaranja goriva, ili izvođenje procesa proizvodnje u automobilskoj industriji, već i zbog porasta količine promjenljivih dijelova i podsklopova, a ponajviše zbog ubrzanog rasta broja vozila koja se povuku iz prometa i rastavljaju. Članak predstavlja materijalno-energetski model životnog vijeka motornog vozila koji uvelike može pomoći prilikom određivanja vrste i veličine troškova materijala i energije, kao i ispuštanja emisija u određenim fazama i cjelokupnog životnog vijeka vozila. Na temelju ulaznih podataka koji se nalaze u [9] predstavljena je analiza rezultata proračuna koji se odnosi na primjere strukture materijala modela vozila od 1990. i 2000. i utjecaja na promjene u potrošnji energije i emisiji štetnih plinova

Whole cell-derived fatty acid profiles of Pseudomonas sp. JS150 during naphthalene degradation

Changes in cellular fatty acid composition during naphthalene degradation, at the concentrations of 0.5 g lñ1 or 1.0 g lñ1,by Pseudomonas sp. JS150 were investigated. In response to naphthalene exposure an increase in saturated/unsaturatedratio was observed. Additionally, the dynamic changes involved alterations in the contents of hydroxy, cyclopropaneand branched fatty acids. Among the classes of fatty acids tested the most noticeable changes in the abundance ofcyclopropane fatty acids were observed. Since day 4 of incubation these fatty acids were not dectected in bacterial cellsgrowing on naphthalene. In contrast, markedly increased in the percentage of hydroxy fatty acids over time wasobserved. However, the proportions of saturated straight-chain and branched fatty acids did not change such significantly