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Search results for: VOLATILE FATTY ACIDS
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Defining a novel domain that provides an essential contribution to site-specific interaction of Rep protein with DNA
PublicationAn essential feature of replication initiation proteins is their ability to bind to DNA. In this work, we describe a new domain that contributes to a replication initiator sequence-specific interaction with DNA. Applying biochemical assays and structure prediction methods coupled with DNA–protein crosslinking, mass spectrometry, and construction and analysis of mutant proteins, we identified that the replication initiator of the...
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Molecular dynamics simulations reveal the balance of forces governing the formation of a guanine tetrad—a common structural unit of G-quadruplex DNA
PublicationG-quadruplexes (G4) are nucleic acid conformations of guanine-rich sequences, in which guanines are arranged in the square-planar G-tetrads, stacked on one another. G4 motifs form in vivo and are implicated in regulation of such processes as gene expression and chromosome maintenance. The structure and stability of various G4 topologies were determined experimentally; however, the driving forces for their formation are not fully...
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How proteins bind to DNA: target discrimination and dynamic sequence search by the telomeric protein TRF1
PublicationTarget search as performed by DNA-binding proteins is a complex process, in which multiple factors contribute to both thermodynamic discrimination of the target sequence from overwhelmingly abundant off-target sites and kinetic acceleration of dynamic sequence interrogation. TRF1, the protein that binds to telomeric tandem repeats, faces an intriguing variant of the search problem where target sites are clustered within short fragments...
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One tube mutation detection using sensitive fluorescent dyeing of MutS protected DNA
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Influence of steam cooking on pro-health properties of Small and Large variety of Momordica charantia
PublicationSteam cooking is one of the most common preparations of Momordicacharantia dishes. This method improved the tastiness of the fruits but at the same time, some changes occurred in the volatile and non-volatile parts of their food matrices. In this study, for the first time these properties were correlated with the found substances affecting the bioactivity of this fruit. Two varieties of Momordicacharantia were analysed and compared....
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Nonprotein nitrogenous compounds
PublicationThe non-protein nitrogen (NPN) fraction is an important group of food components for both technological and nutritional reasons. Free amino acids (FAAs), oligopeptides, amines, nucleic acids, and nucleotides, as well as other low-molecular nitrogen-containing components (cyanogenic glycosides, alkaloids, thiazoles, oxazoles, pyrroles, and pyrazines), are found in most foods. Their content depends on many factors, starting from...
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New Procedures for Control of Industrial Effluents Treatment Processes
PublicationThis work presents the procedures for monitoring volatile organic compounds during treatment of industrial effluents. The investigation was carried out for a specific effluent—caustic effluent from bitumen production. The developed procedures enable more detailed control of the effectiveness of wastewater treatment than standard procedures. Caustic effluents from bitumen production have a complex physicochemical form and consist...
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The potential of LC–MS technique in direct analysis of perfume content
PublicationPerfumes are products that consist of a wide range of natural and synthetic compounds. Due to complex composition, the determination of their ingredients is a difficult task. Most of the perfume components are either volatile or semi-volatile; however, most of the attention has been paid to volatile ones, and thus, gas chromatography or electronic noses are generally used. Nevertheless, in this study, liquid chromatography coupled...
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An LC-MS/MS Method for a Comprehensive Determination of Metabolites of BTEX Anaerobic Degradation in Bacterial Cultures and Groundwater
PublicationBTEX (benzene, toluene, ethylbenzene, and the different xylene isomers), known for carcinogenic and neurotoxic effects, are common environmental contaminants. The first step for the development of the bioremediation technologies is the detection of intense microbial degradation in contaminated waters in the quest for the most active bacterial strains. This requires the multispecies analysis for BTEX metabolites which are considered...
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Production of essential oils from in vitro cultures of Caryopteris species and comparison of their concentrations with in vivo plants
PublicationThe chemical composition of hydrodistilled essential oils obtained from aerial parts and roots of selected Caryopteris (‘bluebeard’) species (C. incana, C. mongolica, Caryopteris 9 clandonensis), as well as the newly established in vitro shoot and adventitious root cultures of the above plants, was analyzed by gas chromatography– mass spectrometry. Essential oil content and composition differed significantly depending on the type...
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Meldrum’s acid assisted formation of tetrahydroquinolin‑2‑one derivatives a short synthetic pathway to the biologically useful scaffold
PublicationA new method for the preparation of tetrahydroquinolin-2-one derivatives is presented. This approach involves a two-step reaction between enaminones and acylating agents, immediately followed by electrophilic cyclization, all within a single synthesis procedure, eliminating the need to isolate intermediates. The entire process is facilitated by the use of acyl Meldrum’s acids which not only shortens the preparation time of the...
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Determination of terpene profiles in potential superfruits
PublicationThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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Carboxylation Enhances Fragmentation of Furan upon Resonant Electron Attachment
PublicationWe report a dissociative electron attachment study to 2-furoic acid (C5H4O3) isolated in a gas phase, which is a model molecule consisting of a carboxylic group and a furan ring. Dissociation of furan by low energy electrons is accessible only via electronic excited Feshbach resonances at energies of incident electrons above 5 eV. On the other hand, carboxylic acids are well- known to dissociate via attachment of electrons at subexcitation energies....
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Synthesis and polymerisation techniques of molecularly imprinted polymers
PublicationMolecularly Imprinted Polymers (MIPs) are materials that has been processed using the molecular imprinting technique which permit to obtain well-defined three-dimensional cavities, with affinity to a template molecule, in the polymer matrix. Technology involves three strategies, i.e., covalent, non-covalent and semi-covalent approach, but the most popular is non-covalent approach. The most important components for the synthesis...
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Evaluation of the prediction ability of air pollutants based on the electronic nose responses
PublicationElectronic noses are able to perform on-line measurements of the toxic volatile compounds in air. Due to their low cost and compact size they can be placed in the areas exposed to pollution, outside the laboratory. Those advantages, on the other side, force the need for development of the reliable sensors data analysis procedures. One of the most important issues connected with electronic noses is the lack of stability of the gas...
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Features extraction from the electrocatalytic gas sensor responses
PublicationOne of the types of gas sensors used for detection and identification of toxic-air pollutant is an electrocatalytic gas sensor. The electrocatalytic sensors are working in cyclic voltammetry mode, enable detection of various gases. Their response are in the form of I-V curves which contain information about the type and the concentration of measured volatile compound. However,...
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Small Polymeric Toys Placed in Child-Dedicated Chocolate Food Products—Do They Contain Harmful Chemicals? Examination of Quality by Example of Selected VOCs and SVOCs
PublicationThis study was focused on child-dedicated chocolate food products that contain a plastic package with a small toy inside (also known as chocolate eggs). Three types of these products that are commercially available on the Polish market, with different prices, chocolate composition, and main types of polymers used in the toy manufacturing process, were investigated. The polymers were identified using Fourier-transform infrared (FT-IR)...
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Impact of the Alkyl Side Chains of Cations and Anions on the Activity and Renaturation of Lysozyme: A Systematic Study Performed Using Six Amino‐Acid‐Based Ionic Liquids
PublicationThe impact of the structure of ionic liquid on the activity and renaturation of lysozyme from the hen egg white (HEWL) was investigated. A set of six ionic liquids based on morpholinium cation and N-acylated amino acids as anions were exploited. The matrix used was based on two homologous series: one with N-acetyl-L-valinate [Val] as a common anion and morpholinium cation with a different number of carbon atoms in the n-alkyl chain...
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Preparation, composition and properties of fish silage produced with post-coagulation sludge
PublicationPost-coagulation sludge was added to fish fydrolyzates (silage). Silage was prepared using whole sprats. Technology of the process has been modified and sulphuric acid was replaced with phosphoric acid. The objective was to evaleuate the quality of produced silage during storage, particulary the changes of peroxide value and amount of free acids in silage fat.
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Rapid Evaluation of Poultry Meat Shelf Life Using PTR-MS
PublicationThe use of proton transfer reaction mass spectrometry (PTR-MS) for freshness classification of chicken and turkey meat samples was investigated. A number of volatile organic compounds (VOCs) were selected based on the correlation (> 95%) of their concentration during storage at 4 °C over a period of 5 days with the results of the microbial analysis. In order to verify if the selected compounds are not sample-specific, a number...
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Electronic noses: Powerful tools in meat quality assessment
PublicationMain factors that are considered by consumers when choosing meat products are colour and aroma, of which the latter is a more reliable indicator of quality. However, a simple sensory evaluation of hedonistic qualities is often not sufficient to determine whether protein is past its shelf life, and consumption of spoiled meat can lead to serious health hazards. Some volatile compounds can be used as spoilage indicators, and so a...
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One-Step Synthesis of b-Lactams with Retro-Amide Side Chain
PublicationAbstract: A one pot synthesis for preparation of 1,4-disubstituted-2-oxo-azetidine-3-carboxylic acid amides was developed. 5-(α-N-substituted-amino-α'-hydroxy)methylene Meldrum's acids act as a source of ketenes that react with aldimines in boiling toluene to give b-lactams with retro-amid side chain.
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Gas chromatography-olfactometry (GC-O), electronic noses (e-noses) and electronic tongues (e-tongues) for in vivo food flavour measurement
PublicationThe capter revies two types of artificial olfaction instrumentation, i.e. gas-chromatography-olfactometry (GC-O) and chemical sensor technologies (electronic nose and tongue), combined with multivariate data processing methods as promising approaches for rapid analysis of food. The chapter also includes examples of specific applications for the detection of food flavour and volatile components.
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Emulsifi ers from renewable materials: an eco-friendly synthesis and properties
PublicationThe focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained...
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In vitro antioxidative and binding properties of phenolics in traditional, citrus and exotic fruits
PublicationMany polyphenols bind proteins, therefore our research was focused on the potential of protein binding to polyphenols of investigated fruits and their health-related effects. The contents of polyphenols and related antioxidant activities of traditional, citrus and exotic fruits were compared. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples and their interaction with human serum albumin (HSA)...
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Exploring the cocrystallization potential of urea and benzamide
PublicationThe cocrystallization landscape of benzamide and urea interacting with aliphatic and aromatic carboxylic acids was studied both experimentally and theoretically. Ten new cocrystals of benzamide were synthesized using an oriented samples approach via a fast dropped evaporation technique. Information about types of known bi-component cocrystals augmented with knowledge of simple binary eutectic mixtures was used for the analysis...
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Chapter 4. Electricity generation from glucose microbial fuel cell
PublicationThe microbial fuel cell was constructed to generate electricity with simultaneous digestion of a glucose fuel by a bacterial biofilm. The decomposition of glucose resulted in releasing of electrons to an anode and to production of some by-products, e.g. metane or organic acids. It was found that maximum electric power density strongly depended on the proton transport through the proton exchange membrane seperating the anolyte and...
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Antiproliferative, Antiangiogenic, and Antimetastatic Therapy Response by Mangiferin in a Syngeneic Immunocompetent Colorectal Cancer Mouse Model Involves Changes in Mitochondrial Energy Metabolism
PublicationIn spite of the current advances and achievements in cancer treatments, colorectal cancer (CRC) persists as one of the most prevalent and deadly tumor types in both men and women worldwide. Drug resistance, adverse side effects and high rate of angiogenesis, metastasis and tumor relapse remain one of the greatest challenges in long-term management of CRC and urges need for new leads of anticancer drugs. We demonstrate that CRC...
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Zastosowanie technik dwuwymiarowych w analizie frakcji lotnej i oznaczaniu związków bioaktywynych owoców jagody kamczackiej
PublicationDotychczasowe doniesienia literaturowe wskazują, że owoce strefy borealnej, do których należy popularna w Polsce aronia, są źródłem cennych składników odżywczych i prozdrowotnych. Podobnie jagoda kamczacka, należąca do tej grupy owoców, może stanowić źródło substancji istotnych dla ludzkiej diety. Jednakże aktualny stan wiedzy o składzie chemicznym owoców jagody kamczackiej ogranicza się głównie do informacji dotyczących całkowitej...
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Production of fuel briquette from solid waste biomass using natural resin as a binder
PublicationBackground: This research aimed to evaluate the use of natural resin as a binder for the production of fuel briquette from solid waste biomass.Methods: Proximate analyses were made for fuel briquette prepared from solid waste biomass using natural resin as a binder in comparison with using starch as a binder.Results: The results for density, percent content of moisture, percent content of volatile matter, percent...
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Production of fuel briquette from solid waste biomass using natural resin as a binder
PublicationAbstract Background: This research aimed to evaluate the use of natural resin as a binder for the production of fuel briquette from solid waste biomass. Methods: Proximate analyses were made for fuel briquette prepared from solid waste biomass using natural resin as a binder in comparison with using starch as a binder. Results: The results for density, percent content of moisture, percent content of volatile matter, percent content...
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A novel analytical approach in the assessment of unprocessed Kaffir lime peel and pulp as potential raw materials for cosmetic applications
PublicationVolatile fraction of fruits is a rich source of bioactive and aroma compounds, which can be used in the cosmetics industry after meeting relevant criteria. This is particularly evident in citrus fruits, especially in Citrus hystrix, in which the headspace consists mainly of terpenes. Due to the insufficient sensitivity of analytical methods, essential oils are used in investigations in contrast to fresh fruits. Therefore, a novel...
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Increased plasma concentration of 4-pyridone-3-carboxamide-1-ß-D-ribonucleoside (4PYR) in lung cancer. Preliminary studies
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Synthesis and Fluorescent Properties of 6-(4-Biphenylyl)-3,9-dihydro-9-oxo-5H-imidazo[1,2-A]purine Analogues of Acyclovir and Ganciclovir
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SYNTHESIS AND FLUORESCENT PROPERTIES OF THE TRICYCLIC ANALOGUES OF ACYCLOVIR LINKED WITH NITROGEN HETBROCYCLIC UNITS
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Thermodynamic, Anticoagulant, and Antiproliferative Properties of Thrombin Binding Aptamer Containing Novel UNA Derivative
PublicationThrombin is a serine protease that plays a crucial role in hemostasis, fibrinolysis, cell proliferation, and migration. Thrombin binding aptamer (TBA) is able to inhibit the activity of thrombin molecule via binding to its exosite I. This 15-nt DNA oligonucleotide forms an intramolecular, antiparallel G-quadruplex structure with a chair-like conformation. In this paper, we report on our investigations on the influence of certain...
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Preparation and some properties of multiblock copoly(amide-b-amide)s
PublicationThe paper concerns the polymers built of oligoamide hard blocks and oligoamide soft blocks (KPAA, formula I). Oligo(laurolactam) (PA12) was used as hard block and the product of reaction of dimerized fatty acid and hexamethylene diamine (PA6,36) was used as a soft one. Effects of molar ratio of these blocks on the following properties of KPAA have been investigated: limiting viscosity number ([2]), degrees of swelling in water...
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Urine headspace analysis in medical diagnostics
PublicationThe analysis of the volatile organic compounds in the bodily fluids such as urine may provide useful information on the patients’ general health. The potential application of urine headspace analysis could facilitate the diagnostics of various diseases such as metabolic disorders, urinary tract diseases and gastrointestinal conditions. Described in this paper are the currently available techniques of urine sample analysis as well...
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Synthesis of 5-Substituted 1H-Tetrazoles from Nitriles in the Presence of Heterogeneous Catalyst
PublicationTetrazoles are five-membered heterocyclic compounds containing in their rings four nitrogen atoms. They have wide applications as corrosion inhibitors, analytical reagents, high-energy materials and gas generating compositions. Tetrazoles also play important role in coordination chemistry as ligands and in medicinal chemistry as metabolically stable surrogates for carboxylic acids. In recent years, investigation of new method of...
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New matrix-free reference material for ethene in the form of optical fibres
PublicationReference materials are indispensable in the qualitycontrol and quality assurance of analytical measurements. Onenovel approach to the generation of standard gaseous mixturesof toxic, reactive, volatile, labile, and malodorous substancesinvolves thermal decomposition or rearrangement, under definedtemperature conditions, of compounds immobilized, bychemical bonding, on the surface of an appropriate carrier torelease specific amounts...
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Ti3C2 MXenes-based catalysts for the process of α-pinene isomerization
PublicationIn this study, the catalytic performance of Ti3C2 MXene materials in the reaction of α-pinene isomerization was demonstrated. The influence of etching agents (HF, HF/H2SO4, and HF/HCl; weight ratios of mixed acids: 1 : 3, 1 : 4, and 1 : 5) on removing Al atoms from MAX phase, creation of an accordion-like structure typical...
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Characterization of two aminotransferases from Candida albicans
PublicationAminoadipate aminotransferase (AmAA) is an enzyme of α-aminoadipate pathway (AAP) for l-lysine biosynthesis. AmAA may also participated in biosynthesis or degradation of aromatic amino acids and in d-tryptophan based pigment production. The AAP is unique for fungal microorganisms. Enzymes involved in this pathway have specific structures and properties. These features can be used as potential molecular markers. Enzymes catalyzing...
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The Effect of Water and Frost on Fatigue Life of Asphalt Concrete
PublicationThis paper presents testing of fatigue life of asphalt concrete that has been subjected to action of water and frost. Simulation of water and frost action was based on the original AASHTO T283 method and its modification. The original method was modified in such a way that instead of a single freeze-thaw cycle, 50 and 150 cycles were applied. Fatigue life was measured in the indirect tensile fatigue test in the Nottingham asphalt...
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Rapeseed oil methyl ester production in an individual household
PublicationFatty acid methyl esters, commonly known as biodiesel, are a cheap and environmental-friendly fuel substitute for diesel engines. Aside from industrial production, individual biodiesel manufacturing is also and important method of fulfilling the requirements of EU Parliament directive no. 2003/30/WE about supporting the use of renewable fuels in transport. Individual FAME production guarantees easy access to the main raw material...
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Quality of limes juices based on the aroma and antioxidant properties
PublicationKaffir (Citrus hystrix) and Key (Citrus aurantifolia) limes juices were investigated and compared. Two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF-MS) was applied to assess the botanical origin of Kaffir and Key limes juices, based on volatile substances. The biggest differences in the contents of selected terpenes in Kaffir and Key limes occur in chemical compounds such as Limonene,...
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Comprehensive two-dimensional gas chromatography - promising technique for analysis of complex food matrices
PublicationThe present paper is focused on brief description of operational principle of comprehensive two-dimensional gas chromatography (GC×GC) technique, instrumentation and data processing. Furthermore, the examples of application in the field of food analysis, performed also in the author's laboratory, are given. The detailed discussion of GC×GC characterization and comparison of the volatile composition of berries of different blue...
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Impact of the Alkyl Side Chains of Cations and Anions on the Activity and Renaturation of Lysozyme: A Systematic Study Performed Using Six Amino‐Acid‐Based Ionic Liquids
PublicationThe impact of the structure of ionic liquid on the activity and renaturation of lysozyme from the hen egg white (HEWL) was investigated. A set of six ionic liquids based on morpholinium cation and N-acylated amino acids as anions were exploited. The matrix used was based on two homologous series: one with N-acetyl-L-valinate [Val] as a common anion and morpholinium cation with a different number of...
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NOBLE METAL MODIFIED TiO2 FOR PHOTOCATALYTIC AIR PURIFICATION
PublicationTiO2 was surface modified with silver, gold, palladium and platinum ion clusters to improve its photocatalytic activity. The effect of metal content, the kind of dopant used during preparation procedure on the photoactivity were investigated. in toluene removal which was used as a model volatile organic compound. Toluene, at the concentration of about 100 ppm, was irradiated over noble metal modified TiO2 using light-emitting diodes...
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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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A new method for real-time monitoring of volatiles in frying fumes using proton transfer reaction mass spectrometry with time-of-flight analyse
PublicationTo safeguard the consumers’ well-being, it is necessary to develop novel methods for determination of carcinogens in food, including volatiles generated during frying. The currently used procedures for analysis of volatile fraction of vegetable oils are not based on real-time measurements and thus do not enable the determination of carcinogenic compounds in frying fumes; instead, only the headspace or liquid fraction is sampled....