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61.
Katarzyna Kosznik-Kwanicka ukasz Grabowski Micha Grabski Mateusz Kaszubski Marcin Grniak Agata Jurczak-Kurek Grzegorz Wgrzyn Alicja Wgrzyn 《International journal of molecular sciences》2020,21(22)
Two newly discovered bacteriophages, isolated from chicken feces and infecting Salmonella enterica strains, are described in this report. These phages have been named vB_Sen-TO17 and vB_Sen-E22, and we present their molecular and functional characterization. Both studied viruses are able to infect several S. enterica strains and develop lytically, but their specific host ranges differ significantly. Electron microscopic analyses of virions have been performed, and full genome sequences were determined and characterized, along with molecular phylogenetic studies. Genomes of vB_Sen-TO17 (ds DNA of 41,658 bp) and vB_Sen-E22 (dsDNA of 108,987 bp) are devoid of homologs of any known or putative gene coding for toxins or any other proteins potentially deleterious for eukaryotic cells. Both phages adsorbed efficiently (>95% adsorbed virions) within 10 min at 42 °C (resembling chicken body temperature) on cells of most tested host strains. Kinetics of lytic development of vB_Sen-TO17 and vB_Sen-E22, determined in one-step growth experiments, indicated that development is complete within 30–40 min at 42 °C, whereas burst sizes vary from 9 to 79 progeny phages per cell for vB_Sen-TO17 and from 18 to 64 for vB_Sen-E22, depending on the host strain. Virions of both phages were relatively stable (from several percent to almost 100% survivability) under various conditions, including acidic and alkaline pH values (from 3 to 12), temperatures from −80 °C to 60 °C, 70% ethanol, chloroform, and 10% DMSO. These characteristics of vB_Sen-TO17 and vB_Sen-E22 indicate that these phages might be considered in further studies on phage therapy, particularly in attempts to eliminate S. enterica from chicken intestine. 相似文献
62.
Katarzyna Szurkowska ukasz Szeleszczuk Joanna Kolmas 《International journal of molecular sciences》2020,21(23)
Powders of α-TCP containing various amounts of silicon were synthesized by two different methods: Wet chemical precipitation and solid-state synthesis. The obtained powders were then physico–chemically studied using different methods: Scanning and transmission electron microscopy (TEM and SEM), energy-dispersive X-ray spectroscopy (EDS), powder X-ray diffractometry (PXRD), infrared and Raman spectroscopies (FT-IR and R), and solid-state nuclear magnetic resonance (ssNMR). The study showed that the method of synthesis affects the morphology of the obtained particles, the homogeneity of crystalline phase and the efficiency of Si substitution. Solid-state synthesis leads to particles with a low tendency to agglomerate compared to the precipitation method. However, the powders obtained by the solid-state method are less homogeneous and contain a significant amount of other crystalline phase, silicocarnotite (up to 7.33%). Moreover, the microcrystals from this method are more disordered. This might be caused by more efficient substitution of silicate ions: The silicon content of the samples obtained by the solid-state method is almost equal to the nominal values. 相似文献
63.
64.
Influence of yeast on the yield of fermentation and volatile profile of ‘Węgierka Zwykła’ plum distillates 下载免费PDF全文
Katarzyna Pielech‐Przybylska Maria Balcerek Agnieszka Nowak Piotr Patelski Urszula Dziekońska‐Kubczak 《Journal of the Institute of Brewing》2016,122(4):612-623
The character of plum brandies depends on a unique aroma profile of the plum and the microbiota present on the surface of the fruits, as well as yeast used for fermentation. In this study, an evaluation of the effect of microorganisms applied for the fermentation of W?gierka Zwyk?a var. plum mashes and processing temperature (18 °C, 30 °C) on its efficiency and volatile profile, as well as taste and flavour of distillates obtained was performed. An estimation of the odour activity values (OAVs) of the volatile compounds was also conducted. Regardless of whether the fermentation was carried out using Saccharomyces bayanus wine yeast or by native microflora present on plums as well as raisins, the efficiency of this process was high and ranged between 91.7 and 96.7% of the theoretical efficiency. Especially rich in esters (among others ethyl acetate and isoamyl acetate) was the distillate derived after fermentation with the microflora of plums and raisins, at 18 °C. An evaluation of the individual aromatic effect of chemical compounds present in tested distillates, in terms of their OAVs, revealed that the highest OAVs were reached with isovaleraldehyde. Other compounds that showed aroma values >1 and possibly had an effect on the overall aroma of tested plum distillates were the following: hexanal, benzaldehyde, ethyl acetate, isoamyl acetate, ethyl benzoate, ethyl hexanoate, 1‐propanol, 2‐methyl‐1‐butanol, 3‐methyl‐1‐butanol and 1‐hexanol. The performed sensory ranking showed that the best rated distillate was the one obtained after fermentation with the indigenous microflora of plums and raisins, at 18 °C. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
65.
Mariusz Szymczak Barbara Szymczak Anna Koronkiewicz Katarzyna Felisiak Mateusz Bednarek 《Journal of food science》2013,78(4):S619-S625
Effects of vinegar, oil, and sour cream brines on meat quality of 4 popular cold marinades from herring were investigated in the study. Cover brine type affected the composition and nutritive value of meat as well as the sensory and microbiological quality of marinated herring. Qualitative differences resulted from cover brine penetration into meat, and from diffusion of components from meat to vinegar brine. Compared to oil and sour cream, vinegar brine contributed to increased concentrations of salt and acetic acid, hardness, color brightness of marinades meat and to increased microbial contamination of meat. Furthermore, vinegar caused nitrogen losses to 15%, including valuable products of protein hydrolysis, enzymes, and total volatile bases. The rolling up of fillets reduced diffusion even by 50%. In turn, oil and sour cream were causing mainly a higher fat content and overall sensory evaluation of the marinades. 相似文献
66.
Joanna Milala Katarzyna Grzelak‐Błaszczyk Michał Sójka Monika Kosmala Agnieszka Dobrzyńska‐Inger Edward Rój 《Journal of Food Processing and Preservation》2018,42(1)
The objective of the work was to elucidate the chemical composition of fractions of oil extracts obtained during the supercritical extraction on a semi‐industrial scale from strawberry (Fragaria x ananassa Duch.), chokeberry [Aronia melanocarpa (Michx.)], and raspberry (Rubus idaeus L.) seeds from industrial press cake. The oil extracts differed in terms of their content of bioactive components: carotenoids, tocopherols, chlorophylls, and fatty acids. Raspberry seed oil was the richest source of tocopherols (620.1–2166.7 mg kg?1) and α‐linolenic acid (above 37%). Chokeberry seed oil had the highest content of linoleic acid (above 70%), and α‐tocopherol (166.0–1104.8 mg kg?1). Strawberry oil was characterized by the highest content of chlorophylls and α‐linolenic acid (above 30%). It was showed that the oil fraction collected at the beginning of extraction is characterized by a high acid value, which requires purification steps to be used for food purposes.
Practical applications
Strawberry, raspberry, and chokeberry by‐products left over from the production of concentrated juice are a valuable source of oils rich in n‐3 and n‐6 polyunsaturated fatty acids, tocopherols, and carotenoids. The research showed that the fractionation of extracts in the course of supercritical extraction leads to oils with varying amounts of different bioactive compounds, and thus to products with potentially wide applications. Seeds oils have high potential utility as a source of unconventional oil for cosmetic and pharmaceutical sectors and biodiesel. Their targeted utilization may be exploited for economic, environmental and health benefits. 相似文献67.
Teresa Glomb Benita Wiatrak Katarzyna Gbczak Tomasz Gbarowski Dorota Bodetko aneta Czynikowska Piotr
witek 《International journal of molecular sciences》2020,21(23)
Numerous studies have confirmed the coexistence of oxidative stress and inflammatory processes. Long-term inflammation and oxidative stress may significantly affect the initiation of the neoplastic transformation process. Here, we describe the synthesis of a new series of Mannich base-type hybrid compounds containing an arylpiperazine residue, 1,3,4-oxadiazole ring, and pyridothiazine-1,1-dioxide core. The synthesis was carried out with the hope that the hybridization of different pharmacophoric molecules would result in a synergistic effect on their anti-inflammatory activity, especially the ability to inhibit cyclooxygenase. The obtained compounds were investigated in terms of their potencies to inhibit cyclooxygenase COX-1 and COX-2 enzymes with the use of the colorimetric inhibitor screening assay. Their antioxidant and cytotoxic effect on normal human dermal fibroblasts (NHDF) was also studied. Strong COX-2 inhibitory activity was observed after the use of TG6 and, especially, TG4. The TG11 compound, as well as reference meloxicam, turned out to be a preferential COX-2 inhibitor. TG12 was, in turn, a non-selective COX inhibitor. A molecular docking study was performed to understand the binding interaction of compounds at the active site of cyclooxygenases. 相似文献
68.
Aneta Kaczor Nikoletta Szemerédi Dr. Katarzyna Kucwaj-Brysz Dr. Monika Dąbrowska Dr. Małgorzata Starek Dr. Gniewomir Latacz Dr. Gabriella Spengler Prof. Jadwiga Handzlik 《ChemMedChem》2021,16(15):2386-2401
ABCB1 modulation is an interesting strategy in the search for new anticancer agents that can overcome multidrug resistance (MDR). Hence, 17 new 5-arylideneimidazolones containing an amine moiety, as potential ABCB1 inhibitors, were designed, synthesized, and investigated. The series was tested in both parental (PAR) and multidrug-resistant (MDR) ABCB1-overexpressing T-lymphoma cancer cells using cytotoxicity assays. The ABCB1-modulating activity was examined in rhodamine 123 accumulation tests, followed by Pgp-Glo™ Assay to determine the influence of the most active compounds on ATPase activity. Lipophilic properties were assessed both, in silico and experimentally (RP-TLC). Pharmacophore-based molecular modelling toward ABCB1 modulation was performed. The studies allowed the identification of anticancer agents (p-fluorobenzylidene derivatives) more potent than doxorubicin, with highly selective action on MDR T-lymphoma cells (selectivity index >40). Most of the investigated compounds showed ABCB1-modulating action; in particular, two 5-benzyloxybenzylidene derivatives displayed activity nearly as strong as that of tariquidar. 相似文献
69.
Tomasz Wokowicz Katarzyna Zacharczuk Rafa Gierczyski Magdalena Nowakowska Katarzyna Piekarska 《International journal of molecular sciences》2021,22(17)
Background: Salmonella Kentucky belongs to zoonotic serotypes that demonstrate that the high antimicrobial resistance and multidrug resistance (including fluoroquinolones) is an emerging problem. To the best of our knowledge, clinical S. Kentucky strains isolated in Poland remain undescribed. Methods: Eighteen clinical S. Kentucky strains collected in the years 2018–2019 in Poland were investigated. All the strains were tested for susceptibility to 11 antimicrobials using the disc diffusion and E-test methods. Whole genome sequences were analysed for antimicrobial resistance genes, mutations, the presence and structure of SGI1-K (Salmonella Genomic Island and the genetic relationship of the isolates. Results: Sixteen of 18 isolates (88.9%) were assigned as ST198 and were found to be high-level resistant to ampicillin (>256 mg/L) and quinolones (nalidixic acid MIC ≥ 1024 mg/L, ciprofloxacin MIC range 6–16 mg/L). All the 16 strains revealed three mutations in QRDR of GyrA and ParC. The substitutions of Ser83 → Phe and Asp87 → Tyr of the GyrA subunit and Ser80→Ile of the ParC subunit were the most common. One S. Kentucky isolate had qnrS1 in addition to the QRDR mutations. Five of the ST198 strains, grouped in cluster A, had multiple resistant determinants like blaTEM1-B, aac(6′)-Iaa, sul1 or tetA, mostly in SGI1 K. Seven strains, grouped in cluster B, had shorter SGI1-K with deletions of many regions and with few resistance genes detected. Conclusion: The results of this study demonstrated that a significant part of S. Kentucky isolates from humans in Poland belonged to ST198 and were high-level resistant to ampicillin and quinolones. 相似文献
70.
Ewa ya Katarzyna Dziendzikowska Dariusz Kamola Jacek Wilczak Rafa Sapierzyski Joanna Harasym Joanna Gromadzka-Ostrowska 《International journal of molecular sciences》2021,22(9)
Background: The incidence of Crohn’s disease (CD) is increasing worldwide, and it has currently become a serious public health issue in society. The treatment of CD continues throughout a patient’s lifetime, and therefore, it is necessary to develop new, effective treatment methods, including dietotherapy. The present study aimed to determine the effects of consumption of oat beta-glucans with different molar mass on colon inflammation (colitis) in the early stages of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD in an animal model. Methods: Sprague–Dawley rats (control and TNBS-induced CD) were divided into three dietary groups and fed for 3 days (reflecting acute inflammation) or 7 days (reflecting remission) with a feed containing 1% low (βGl) or high (βGh) molar mass oat beta-glucan or a feed without this polysaccharide. The level of colon inflammatory markers and the expression of cytokines and their receptor genes were measured by ELISA and RT-PCR methods, respectively. Results: Acute inflammation or remission (3 or 7 days after TNBS administration, respectively) stages of experimentally induced CD were characterized by an increase in the level of inflammatory markers (IL-1, IL-6, IL-10, IL-12, TNF-α, CRP, MPO, COX, and PGE2) and the disruption of some cytokine signaling pathways as well as macro- and microscopic changes of colon tissue. The consumption of oat beta-glucans reduced the level of inflammatory markers and recovered the signaling pathways and histological changes, with stronger effects of βGl after 7 days of colitis. Conclusions: Dietary oat beta-glucans can reduce colitis at the molecular and organ level and accelerate CD remission. 相似文献