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Search results for: FATTY ACID COMPOSITION
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On the Mechanism of Electrochemical Oscilations in Three-Phase System Containing Nitrobenzene with Picric Acid as Liquid Membrane.O mechaniźmie oscylacji róznicy potencjału elektorchemicznego w trójfazowych układach zawierających nitrobenzen z kwasem pikrynowym jako membraną ciekłą.
PublicationPodano składowe różnicy potencjału elektrochemicznego między fazami wodnymi oscylatora z nitrobenzynową membraną ciekłą. Na tej podstawie oraz zmian stężeń składników układu w trakcie procesu zaproponowano mechanizm powstawania oscylacji w którym najważniejszą rolę odgrywają procesy adsorpcji/desorpcji surfaktantu na granicach faz.
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Untargeted Lipidomics Reveals Differences in the Lipid Pattern among Clinical Isolates of Staphylococcus aureus Resistant and Sensitive to Antibiotics
PublicationStaphylococcus aureus resistance to antibiotics is a significant clinical problem worldwide. In this study, an untargeted lipidomics approach was used to compare the lipid fingerprints of S. aureus clinical isolates that are resistant and sensitive to antibiotics. High-performance liquid chromatography coupled with time-of-flight mass spectrometry was employed to rapidly and comprehensively analyze bacterial lipids. Chemometric...
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Photocatalytical properties of maze-like MoO3 microstructures prepared by anodization of Mo plate
PublicationIn this work, we present a simple method of the formation of MoO3 microstructures via an electrochemical anodization of Mo plate carried out under varied conditions. The morphology, composition and structure of samples were investigated by SEM, EDX, XRD and Raman spectroscopy. The band gap energy was estimated using the Kubelka–Munk function and was found to be 2.87 eV. Finally, the photocatalytic activities of MoO3 samples were...
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Phenolic compounds from Nerium oleander leaves: microwave assisted extraction, characterization, antiproliferative and cytotoxic activities
PublicationA microwave-assisted extraction (MAE) method was used for the extraction of phenolic compounds from Nerium oleander leaves. The influence of variables such as ethanol concentration, microwave power, irradiation time and liquid/solid ratio on polyphenol extraction was modelled using a second-order regression equation based on response surface methodology (RSM). The optimal conditions for MAE were: extraction solvent 35% ethanol...
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Składowiska odpadów komunalnych jako źródła emisji zanieczyszczeń do środowiska
PublicationCelem pracy było przeprowadzenie badań mających na celu określenie związków uwalnianych do powietrza ze składowisk odpadów komunalnych oraz charakterystyka ich właściwości zapachowych i toksycznych. Próbki powietrza analizowano za pomocą techniki TD-GC-MS. Przeprowadzone badania pozwoliły na zidentyfikowanie następujących związków: styren, benzen, ksylen, toluen, etylobenzen, disiarczek dimetylu, dekan, kwas butanowy i octowy....
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Budowa niskokalorycznych strukturyzowanych lipidów otrzymanych na drodze enzymatycznego przeestryfikowania oleju rzepakowego i oleiny palmowej kwasem behenowym. The structure of low-calorie structured lipids obtained by enzymatic interestrification of rapeseed oil and palm oil with behenoic acid.
PublicationNiskokaloryczne strukturyzowane lipidy otrzymano na drodze wbudowywania kwasu behenowego, charakteryzującego się niską strawnością, w pozycje sn-1,3 triacylogliceroli dwóch rodzajów oleju rzepakowego oraz oleiny polmowej. Reakcje acydolizy przeprowadzono w obecności biokatalizatora Lipozyme RM IM przez 3 godziny w temp. 72st.C. Otrzymane produkty po usunięciu wolnych kwasów tłuszczowych rozdzielono w kolumnie chromatograficznej...
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Pochodne kwasu neopentylidenofosforoditiowego jako substraty do syntezy ugrupowania trisulfidowego
PublicationBadania przeprowadzone w Katedrze Chemii Organicznej Wydziału Chemicznego Politechniki Gdańskiej na przestrzeni ostatnich kilku lat, pokazały wszechstronność pochodnych kwasu neopentylidenofosforoditiowego [32] w syntezie symetrycznie i niesymetrycznie podstawionego ugrupowania disulfidowego. Wyniki powyższych badań doprowadziły do opracowania nowej strategii syntetycznej, umożliwiającej otrzymywanie...
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Opracowanie dogodnej metody tworzenia wiązań S-C o hybrydyzacji atomu węgla sp oraz sp2
PublicationBadania przeprowadzone w Katedrze Chemii Organicznej Wydziału Chemicznego Politechniki Gdańskiej na przestrzeni ostatnich kilku lat, pokazały wszechstronność pochodnych kwasu neopentylidenofosforoditiowego. Dotychczasowe wyniki badań doprowadziły mnie do opracowania nowych strategii syntetycznych, umożliwiających otrzymywanie związków zawierających wiązanie C-S o hybrydyzacji atomu węgla sp oraz sp2. Analizując wyniki badań opracowałam...
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Anomalous Behavior of Hyaluronan Crosslinking Due to the Presence of Excess Phospholipids in the Articular Cartilage System of Osteoarthritis
PublicationLubrication of articular cartilage is a complex multiscale phenomenon in synovial joint organ systems. In these systems, synovial fluid properties result from synergistic interactions between a variety of molecular constituent. Two molecular classes in particular are of importance in understanding lubrication mechanisms: hyaluronic acid and phospholipids. The purpose of this study is to evaluate interactions between hyaluronic acid...
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4- (Tri-tert-butoxysilylthiomercurio)benzoic acid. Acta Cryst. Sect. E Struct. Rep. [online]**2003 vol. 59 s. m125-m127, 2 rys. 2 tab. bibliogr. 12 poz. Kwas 4-(tri-tert-butoksysililotiortęcio)benzoesowy.
PublicationTytułowy związek otrzymano poprzez reakcję kwasu 4-hydroksyrtęciobenzoesowe-go z tri-tert-butoksysilanotiolem. Przy użyciu rentgenowskiej analizy struk-turalnej monokryształów wyznaczono strukturę cząsteczkową i krystaliczną te-go związku.
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Utilization of oriented crystal growth for screening of aromatic carboxylic acids cocrystallization with urea
PublicationThe possibility of molecular complex formation in the solid state of urea with benzoic acid analogues was measured directly on the crystallite films deposited on the glass surface using powder X-ray diffractometry (PXRD). Obtained solid mixtures were also analyzed using Fourier transform infrared spectroscopy (FTIR). The simple droplet evaporation method was found to be efficient, robust, fast and cost-preserving approach for first...
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Photoactivity of decahedral TiO2 loaded with bimetallic nanoparticles: Degradation pathway of phenol-1- 13 C and hydroxyl radical formation
PublicationDecahedral TiO2decorated with bimetallic nanoparticles were synthesized via radiolysis and photode-position method. The effect of bimetallic surface composition (Ag Pt, Ag Au, Au Pd, Au Pt) as well asdeposition technique (simultaneous or sequential) on the photocatalytic activity in phenol degradationand efficiency of hydroxyl radicals generation under UV–vis light irradiation were investigated. Modifiedand pristine decahedral...
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Surface modification of PMMA polymer and its composites with PC61BM fullerene derivative using an atmospheric pressure microwave argon plasma sheet
PublicationThis paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PC61BM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. The experimental parameters were: an argon (Ar) flow rate (up to 20 NL/min), microwave power (up to 530 W), number...
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Preparation and photocatalytic properties of BaZrO 3 and SrZrO 3 modified with Cu 2 O/Bi 2 O 3 quantum dots
PublicationIn this study, we report a novel method of BaZrO3 and SrZrO3 surface modification by two different types of quantum dots (QDs, Cu2O and Bi2O3), which improved the photocatalytic performance of the obtained materials under UV-Vis light irradiation. Pristine BaZrO3 and SrZrO3 were prepared by the hydrothermal method. The deposition of Cu2O- and Bi2O3-QDs was carried out by chemical reduction. The morphology of the nanoparticles was...
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Bacterial cellulose vs. bacterial cellulose nanocrystals as stabilizer agents for O/W pickering emulsions
PublicationThe growing interest in Pickering emulsions in functional food systems resulted in the need to find suitable stabilizers for them. The work considers the use of bacterial cellulose for this purpose, and its aim was to compare the properties of disintegrated bacterial cellulose, before and after freeze-drying, and its nanocrystals obtained using H2SO4 under variable of time and concentration conditions. The structure of nanocrystals...
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Recovery and re-use of photovoltaic solar cells from crystalline silicon
PublicationCrystalline silicon-type PV modules consist, in order of mass, of glass, an aluminium frame, an EVA coating, solar cells, a terminal box, back film and tapping screws. From the economic point of view, pure silicon, recoverable from spent cells, is the most important material owing to its cost and shortage. For crystalline, silicon-based PV cells, the following chemical treatments were performed: removal of the metal coating, followed...
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Water Footprint Assessment of Selected Polymers, Polymer Blends, Composites, and Biocomposites for Industrial Application
PublicationThis paper presents a water footprint assessment of polymers, polymer blends, composites, and biocomposites based on a standardized EUR-pallet case study. The water footprint analysis is based on life cycle assessment (LCA). The study investigates six variants of EUR-pallet production depending on the materials used. The system boundary included the production of each material and the injection molding to obtain a standardized...
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The characterization of collagen‑based scaffolds modified with phenolic acids for tissue engineering application
PublicationThe aim of the experiment was to study the morphology of collagen-based scaffolds modified by caffeic acid, ferulic acid, and gallic acid, their swelling, and degradation rate, as well as the biological properties of scaffolds, such as antioxidant activity, hemo- and cytocompatibility, histological observation, and antibacterial properties. Scaffolds based on collagen with phenolic acid showed higher swelling rate and enzymatic...
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Hydrodynamic cavitation based advanced oxidation processes: Studies on specific effects of inorganic acids on the degradation effectiveness of organic pollutants
PublicationThe use of cavitation in advanced oxidation processes (AOPs) to treat acidic effluents and process water has become a promising trend in the area of environmental protection. The pH value of effluents – often acidified using an inorganic acid, is one of the key parameters of optimization process. However, in the majority of cases the effect of kind of inorganic acid on the effectiveness of degradation is not studied. The present...
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TMSCL as a rate accelerating additive in acylations of amines with 5-(α- amino-α'-hydroxy)methylene meldrum's acids
PublicationAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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Tmscl as a rate accelerating additive in acylations of amines with 5-(α-amino- α'-hydroxy)methylene meldrum's acids
PublicationAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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TMSCl Promoted Acylation of Amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids - Elucidation of Mechanism.
PublicationRecently we have observed accelerating influence of trimethyl silyl chloride addition on the rate of the reactions of 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids with amines, particularly in the case of highly basic amines. However the nature of the aforementioned process remain unexplained. In proposed communication we wish to report insightful elucidation of this mechanism. The reaction under investigation involves simply...
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Application of analytical methods for the determination of bioactive compounds in some berries
PublicationFluorometry, ESI-MS, FTIR, and radical scavenging assays were used for characterization of bioactive compounds and the levels of their antioxidant activities. Polyphenols, flavonoids, anthocyanins, and ascorbic acid and the level of antioxidant activity of water extracts of “Murtilla-like” [Myrteola nummularia (Poiret) Berg.], and other widely consumed berries were determined and compared. The contents of bioactive compounds and...
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Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells
PublicationSalvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4 naphthoquinone-induced...
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INVESTIGATION OF ACIDIC SOLUTIONS BY POTENTIOMETRIC TASTE SENSOR WITH ALL SOLID STATE ELECTRODES
PublicationPotentiometric taste sensors with electrodes containing lipophilic compound / polymer membranes were already used to distinguish commercial liquid products. In this paper a new potentiometric taste sensor consisting of six All Solid State Electrodes (ASSEs) has been presented. Each of the membrane contains a selected lipophilic compound. The set-up consists of a reference electrode and six ASSEs. The inner layer made of a conducting...
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Mechanism of Isomerization and Acid-Induced Transformations of 3-Hydroxy-4,4'-dimethoxy-3'-methyl-3-oxo-7,7'-bis(piperidino-carbonyloxy)-2,2'-spirobi-[2H,2'H,3H,3'H-benzo[b]thiophene]. Unusual Equilibrium between the Spiro and 3-Hydroxy-benzothiophene Systems.
PublicationStwierdzono, że 3'-hydroksy-4,4'-dimetoksy-3'-metylo-3-okso-7,7'-bis(piperydynokarbonyloksy)-2,2'-spirobi[2H,2'H,3H,3'H-benzo[b]tiofen] występuje w roztworach postaci mieszaniny dwóch diastereoizomerów pozostających w dynamicznej równowadze. Mechanizm tej równowagi oparty jest na odwracalnym otwarciu pierścienia z 1,5 przeniesieniem protonu i utworzeniu przjściowej formy 3-hydroksybenzotiofenu.
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Synergistic Effects of Propolis Combined with 2-Phenoxyethanol and Antipyretics on the Growth of Staphylococcus aureus
PublicationThe present investigation aimed to assess the combinational effect of commonly usedantipyretics and antiseptics with ethanolic extracts of propolis (EEPs) on the growth inhibition ofStaphylococcus aureus. The broth microdilution checkerboard assay revealed synergistic interactionsbetween all investigated antipyretics, namely acetylsalicylic acid, ibuprofen, and acetaminophen,with EEPs samples. The values of the fractional inhibitory...
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Nitrogen and phosphorus compounds in coastal aquifers in Puck municipality area (northern Poland)
Publication1. Groundwater study shows local variations in chemical composition of selected aquifers caused by human impact The diversity is mainly manifested in • time variation of groundwater chemical composition of all analyzed parameters especially in shallow aquifers (Q1) • relationship between t he ground water chemical composition and depth of the aquifer where an inverse concentration distribution occurs higher concentrations are observed...
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Pre-treatment of bio fraction waste prior to fermentation processes
PublicationCurrent efforts are taken to increase resource efficiency, close material loops, and improve sustainable waste and by-products management. Thus, networking agro-food by-products and converting them into valuable products completely exhausting the potential of the raw material becomes significant. Model lignocellulosic and starch based biomass were subjected to pre-treatment with the application of acidic compounds, i.e. sulphuric...
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Synthesis of amides under microwave irradiation
PublicationAmides belong to the most important carboxylic acid derivatives. They are constituents of natural compounds like peptides and proteins. They found applications in many branches of science and industry, especially in pharmaceutical and polymer science. Conventional procedures for amide preparation involve reaction between amine and carboxylic acid or their more active derivatives such as acid chlorides, acid anhydrides or esters....
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Elemental characteristics of mushroom species cultivated in China and Poland
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Determination of biogenic amines in processed and unprocessed mushrooms from the Polish market
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Particle swarm optimization–artificial neural network modeling and optimization of leachable zinc from flour samples by miniaturized homogenous liquid–liquid microextraction
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HPLC-coupled post-column derivatization aims at characterization and monitoring of plant phytocomplexes, not at assessing their biological properties
PublicationTwo recent decades of research identified a number of environmental factors as well as mechanisms leading to pathogenic processes in the human organism. A common factor in pathogenesis of many diseases is oxidative stress, a condition in which the production of damaging reactive oxygen species (ROS), present in the body as an inevitable consequence of respiration and exacerbated by the inflammatory response and by exogenous factors...
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Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation
PublicationThe main goal of this paper is to discuss the problems associated with antioxidant profiling in complex samples using a high-throughput HPLC system coupled with post-column derivatisation reactor. Based on the experimental data reported in the literature, we demonstrated that improper optimisation of temperature and/or pH assay conditions performed using an on-line derivatisation reactor may substantially change the antioxidant...
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Combination of homogeneous liquid–liquid extraction and vortex assisted dispersive liquid–liquid microextraction for the extraction and analysis of ochratoxin A in dried fruit samples: Central composite design optimization
PublicationThis paper presents a new analytical procedure based on combination of homogeneous liquid–liquid extraction (HLLE) and vortex-assisted dispersive liquid–liquid microextraction (VA-DLLME) for the accurate and reliable determination of ochratoxin A (OTA) in dried fruit samples. To enable selective extraction of the OTA, six hydrophobic deep eutectic solvents (hDESs) were prepared and tested as extraction solvents. Optimization of...
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Ionogel sorbent coatings for determining organophosphorus and pyrethroid insecticides in water and fresh juice samples by headspace-solid phase microextraction
PublicationThe sol–gel method yielded three different ionogel sorbent coatings that were obtained based on a silica material containing ionic liquids (ILs) immobilized in its pores. Two ILs, triethylsulfonium bis(trifluoromethylsulfonyl) imide [Set3][TFSI] and 1-butyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide [C4C1Pip][TFSI], as well as their equimolar mixture [Set3/C4C1Pip], were used to obtain ionogel fibers. The developed...
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Analysis of bisphenols and their derivatives in infant and toddler ready-to-feed milk and powdered milk by LC MS/MS
PublicationReady-to-feed milk and powdered milk packed in different types of packaging lined with resin are chosen as the primary or complementary diet for infants and toddlers. An HPLC–MS/MS method was established and validated for the determination of nineteen bisphenols and their derivatives in such samples. The recoveries were from 31% to 120%, while the values of limit of detection and quantification were in the range of 0.24–0.40 and...
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Application of chemometric modeling for ionic liquid-based ultrasonic-assisted dispersive liquid-liquid microextraction: Analysis of fosetyl-aluminum in fruit and vegetable samples
PublicationThis manuscript presents a new method for selective extraction and determination of fosetyl-aluminum in fruits and vegetable samples based on ultrasonic-assisted dispersive liquid-liquid microextraction method using ionic liquids (IL-UA-DLLME). A UV-Visible spectrophotometer was used for detection and quantification. Plants used for sample collection were grown under controlled conditions in a greenhouse. Central composite design...
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Mercury content in beetroot and beetroot-based dietary supplements
PublicationTotal mercury (THg) concentrations in fifty-four beetroot-based DSs and seven lots of conventional and organic beetroots (divided into unpeeled, peeled, and skins) were determined by direct thermal decomposition-gold amalgamation cold vapour atomic absorption spectrometry. The analytical procedure was optimised and validated. The recovery (%) for Hg was 101.9 and 92.73 in BCR-463 and DOLT 4, respectively. The intermediate precision...
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Extraction and Analysis of Bisphenols and Their Derivatives in Infant and Toddler Ready-to-feed Meals by Ultrasound-assisted Membrane Extraction Followed by LC MS/MS
PublicationThis research developed an ultrasound-assisted membrane extraction coupled with liquid chromatography-tandem mass spectrometry method for the determination of nineteen bisphenols and their derivatives in infant and toddler ready-to-feed meals. The calibration curves for all analytes were linear in the tested range, and the limit of detection and limit of quantitation were in the range 0.27 to 0.79 ng/g and 0.80 to 2.4 ng/g, respectively....
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Optimization of vortex-assisted supramolecular solvent-based liquid liquid microextraction for the determination of mercury in real water and food samples
PublicationA novel method was developed for sample preparation for spectrophotometric determination of Hg(II) in water and food samples. The method was based on vortex-assisted supramolecular solvent-assisted liquid-liquid microextraction (VA-SUPRASs-LLME). Analytical parameters such as pH, chelating agent, solvent type and volume, vortex time and salting out effect were optimized. Surface and normal probability plots were drawn for the variables...
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Thermal and spectroscopic profiles variation of cold-pressed raspberry seed oil studied by DSC, UV/VIS, and FTIR techniques
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Variability of elements and nutritional value of spiny-cheek crayfish (Faxonius limosus, Rafinesque, 1817)
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In vitro bioaccessibility of macro and trace elements in biofortified and conventional farmed gilthead seabream (Sparus aurata) and common carp (Cyprinus carpio)
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Comparison of the contents of bioactive compounds and the level of antioxidant activity in different kiwifruit cultivars
PublicationGłównym celem prowadzonych badań było stwierdzenie która z odmian owoców kiwi (''Hayward'', ''Daeheuhg'', ''Haenam'' oraz ''Bidan'') jest najbardziej odpowiednią z punktu widzenia konsumpcji przez człowieka. Z tego powodu w odpowiednio przygotowanych próbkach ekstraktów z owoców kiwi oznaczono:- profile związków bioaktywnych;- poziomy aktywności przeciwutleniającej. Wyniki pomiarów zawartości polifenoli (flawonoidy oraz kwasy fenolowe)...
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Comparative Study on Assisted Solvent Extraction Techniques for the Extraction of Biologically Active Compounds from Sideritis raeseri and Sideritis scardica
PublicationThe plants in the Sideritis genus are postulated to exhibit several important medicinal properties due to their unique chemical composition. To isolate the targeted phytochemical compounds, the selection of a suitable extraction method is of primary importance. In this work, a comparative study on the phytochemical profiles of various Sideritis raeseri and Sideritis scardica extracts has been carried out. An untargeted metabolomics...
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Versatility of putative aromatic aminotransferases from Candida albicans.
PublicationAmino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme...
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Influence of alkaline and oxidative pre-treatment of waste corn cobs on biohydrogen generation efficiency via dark fermentation
PublicationStages of waste corn cobs processing leading to the production of biohydrogen via dark fermentation are presented and discussed in this paper. Firstly, the effects of pretreatment conditions i.e. alkaline, alkaline-oxidizing and Fenton oxidizing pre-treatment of lignocellulosic biomass on the removal of lignin were examined. The solid residue obtained in the first stage was subjected to saccharification by means of enzymatic hydrolysis....
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Thermal Decomposition of Carbamoyl Meldrum’s Acids: A Starting Point for the Preparation of 1,3-Oxazine Derivatives
PublicationThe ability to undergo [4 + 2] versus [2 + 2] cycloaddition was under investigation for ketenes thermally generated from carbamoyl Meldrum’s acid. Usually, 1,3-oxazino-5-carbamoylo-4,6-diones are formed when carbamoyl Meldrum’s acid reacts with imine. However, in some cases, a reaction takes an unexpected course, leading to the formation of tetraponerines alkaloids derivatives or cyclic iminoethers.