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Search results for: Acids
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Synthesis and biological evaluation of novel analogues of batracylin with synthetic amino acids and adenosine: an unexpected effect on centromere segregation in tumor cells through a dual inhibition of topoisomerase IIa and Aurora B
PublicationIn the search for new anticancer agents we designed and synthesized batracylin derivatives with linking synthetic amino acid side chains of different lengths and adenosine. Unexpectedly, we have found that in water and the culture media adenosine–amino acid–BAT conjugates form supramolecular structures and this prevents these compounds from entering cells. Consequently, these compounds exerted no biological activity when tested...
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Application of Headspace Solid-phase Microextraction with Poly(1-vinyl-3- Hexylimidazolium Chloride) Polymeric Ionic Liquid Coating using GC - MS to Determine Volatile Fatty Acids in Dairy Wastewater
PublicationVolatile fatty acids were determined in this study using headspace solid-phase microextraction (HS-SPME) with a poly(1-vinyl-3-hexylimidazolium chloride) polymeric ionic liquid coated fiber followed by gas chromatography - mass spectrometry. Experimental parameters such as extraction time and temperature, sample volume as well as desorption time and temperature were optimized. Detection limits of the method were in the range of...
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Determination of volatile fatty acids in municipal wastewater and leachates from sewage sludge allotments and compost piles using direct aqueous injection gas chromatography preceded by distillation based sample cleanup
PublicationOpracowano metodykę i wykorzystano ją do oznaczania lotnych kwasów tłuszczowych w zanieczyszczonych próbkach wodnych,takich jak ścieki komunalne, odcieki ze składowiska osadów ściekowych i pryzm kompostu, stosując metodę bezpośredniego dozowania rzeczywistej próbki wodnej lub jej rektyfikatu do chromatografu gazowego.
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The effect of high molecular weight bio-based diamine derivative of dimerized fatty acids obtained from vegetable oils on the structure, morphology and selected properties of poly(ether-urethane-urea)s
PublicationIn this work, the effect of the high molecular weight bio-based diamine on the chemical structure and selected properties of poly(ether-urethane-urea)s has been investigated. The ether-urethane prepolymer was cured using 1,4-butanediol and/or bio-based diamine. Mentioned chain extenders were used separately or in the mixture, and their different molecular weight and chemical structure resulted in obtaining materials with diversified...
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Oznaczanie śladowych ilości związków organicznych w próbkach o złożonych matrycach zgodne z regułami ''zielonej chemii analitycznej''. Krótkołańcuchowe kwasy karboksylowe = Increasingly green approaches to the determination of selected trace organic in complex matrices. Short chain carboxylic acids
PublicationNowadays the great stress is put on environment protection and the activities to minimize the effect of chemical analyses on the environment are discussed. When environmentally friendly methodologies of analytes determination are applied the term "green analytical chemistry" is used. In general, the determination of organic compounds in complex matrices, which is a frequent analytical task, requires separation of sample components...
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Distillation cleanup preceded gc determination of short-chain monocarboxylic acids in aqueous and solid samples of wastewater origin = Oznaczanie krótkołańcuchowych kwasów monokarboksylowych w próbkach wodnych i stałych pochodzących z oczyszczalni ścieków z wykorzystaniem chromatografii gazowej poprzedzonej destylacją
PublicationShort-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work...
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Zastosowanie połączenia mikroekstrakcji do fazy stacjonarnej i chromatografii gazowej do oznaczania lotnych kwasów tłuszczowych w próbkach środowiskowych i pokrewnych=Application of combination of solid phase microextraction and gas chromatography for determination of volatile fatty acids in environmental and related samples
PublicationOznaczanie lotnych kwasów tłuszczowych (LKT) w próbkach środowiskowych wymaga najczęściej izolacji i wzbogacania analitów na etapie przygotowania próbek oraz zastosowania techniki o dużym potencjale separacyjnym i identyfikacyjnym na etapie oznaczeń końcowych. W pracy dokonano krytycznego przeglądu zastosowań wygodnej i często stosowanej techniki mikroekstrakcji do fazy stacjonarnej (SPME) w połączeniu z wysokosprawną techniką...
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Plasma free amino acid profiling as metabolomic diagnostic and prognostic biomarker in paediatric cancer patients: a follow‑up study
PublicationAmino acids (AAs) play a crucial role in cancer cell metabolism. Levels of 22 plasma AAs at the time of diagnosis and after treatment were established among 39 pediatric cancer patients and 33 healthy children. Glutamic acid levels decreased and tryptophan levels increased during treatment. Cancer patients presented significantly lower levels of glutamine and leucine post-treatment while levels of 12 other AAs were higher comparing...
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Counter-ion effect on antistaphylococcal activity and cytotoxicity of selected antimicrobial peptides
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Correction to: Plasma free amino acid profiling as metabolomic diagnostic and prognostic biomarker in paediatric cancer patients: a follow-up study
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Retro analog concept: comparative study on physico-chemical and biological properties of selected antimicrobial peptides
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Taurine as a water structure breaker and protein stabilizer
PublicationThe enhancing effect on the water structure has been confirmed for most of the osmolytes exhibiting both stabilizing and destabilizing properties in regard to proteins. The presented work concerns osmolytes, which should be classified as “structure breaking” solutes: taurine and N,N,N-trimethyltaurine (TMT). Here, we combine FTIR spectroscopy, DSC calorimetry and DFT calculations to gain an insight into the interactions between...
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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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TspGWI, a thermophilic class-IIS restriction endonuclease from Thermus sp.,recognizes novel asymmetric sequence 5´-ACGGA(N11/9)-3
PublicationA novel prototype class-IIS restriction endonuclease, TspGWI, was isolated from the thermophilic bacterium Thermus sp. GW. The recognition sequence and cleavage positions have been established: TspGWI recognizes the non-palindromic 5-bp sequence 5′-ACGGA-3′ and cleaves the DNA 11 and 9 nt downstream in the top and bottom strand, respectively. In addition, an accompanying endonuclease, TspGWII, an isoschizomer of Pst I, was found...
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A new Thermus sp. class-IIS enzyme subfamily: isolation of a ''twin'' endo nuclease TspDTI with a novel specificity 5´-ATGAA(N11/9)-3´, related to TspGWI, Taqll and Tth111II. 5´-ATGAA(N11/9)-3´, spokrewnionej z TspGWI, TaqII i Tth111II.
PublicationOdkryto i scharakteryzowano nową subrodzinę enzymów klasy IIS z Thermus sp.
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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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H2AX phosphorylation, its role in DNA damage response and cancer therapy
PublicationDouble-strand breaks (DSBs) are the most deleterious DNA lesions, which, if left unrepaired, may have severe consequences for cell survival, as they lead to chromosome aberrations, genomic instability, or cell death. Various physical, chemical, and biological factors are involved in DSB induction. Cells respond to DNA damage by activating the so-called DNA damage response (DDR), a complex molecular mechanism developed to detect...
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Isolation and identification of the restriction endonuclease Ptal fromPhormidium tadzschicicum, an isoschizomer of BspMII
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Targeted DNA oxidation by LSD1–SMAD2/3 primes TGF-β1/ EMT genes for activation or repression
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Endogenous oxidative DNA base modifications analysed with repair enzymes and GC/MS technique
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The SERRATE protein is involved in alternative splicing in Arabidopsis thaliana
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The SERRATE protein is involved in alternative splicing in Arabidopsis thaliana
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SERRATE interacts with the nuclear exosome targeting (NEXT) complex to degrade primary miRNA precursors in Arabidopsis
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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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UNRES server for physics-based coarse-grained simulations and prediction of protein structure, dynamics and thermodynamics
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DNAffinity: a machine-learning approach to predict DNA binding affinities of transcription factors
PublicationWe present a physics-based machine learning approach to predict in vitro transcription factor binding affinities from structural and mechanical DNA properties directly derived from atomistic molecular dynamics simulations. The method is able to predict affinities obtained with techniques as different as uPBM, gcPBM and HT-SELEX with an excellent performance, much better than existing algorithms. Due to its nature, the method can...
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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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Conformational analysis of N-isopropylbenzohydroxamic acids:Crystal structure, DFT and NMR studies
PublicationCelem pracy było znalezienie różnic strukturalnych dwóch wybranych kwasów N-izopropylobenzhydroksamowych, które rzutują na ich zaobserwowaną wcześniej zróżnicowaną reaktywność wobec odczynników elektrofilowych i porównanie ich budowy z budową znanych kwasów N-metylobenzhydroksamowych. Na podstawie analizy rentgenostrukturalnej monokryształu, obliczeń kwantowo-mechanicznych metodami ab initio oraz DFT w fazie gazowej oraz wyników...
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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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Increased plasma concentration of 4-pyridone-3-carboxamide-1-ß-D-ribonucleoside (4PYR) in lung cancer. Preliminary studies
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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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Creation of Hydrogen Bonded 1D Networks by Cocrystallization of N,N`-bis(2-pyridyl) aryldiamines with Dicarboxylic Acids.Tworzenie 1D sieci krystalicznych poprzez kokrystalizację N,N` -bis(2-piry- dylo) arylodiamin z kwasami dikarboksylowymi.
PublicationZsyntetyzowano szereg N,N`-bis(2-pirydylo) arylodiamin, a następnie otrzymano serię kompleksów w/w amin z kwasami dikarboksylowymi oraz kwasem kwadratowym w postaci monokryształów. Jednostki N,N`-bis(2-pirydylo) arylodiamin i kwasy dikarboksylowe oddziaływują ze sobą poprzez wiązania wodorowe tworząc ośmioczłonowy cykliczny układ. W kompleksach 1:1 cząsteczki układają się w jedno-wymiarową sieć krystaliczną tworzoną przy udziale...
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ABSORPCJA, METABOLIZM I ROLA BIOLOGICZNA KWASÓW NUKLEINOWYCH OBECNYCH W ŻYWNOŚCI
PublicationKwasy nukleinowe należą do niedocenianych składników żywności, szczególnie surowej lub nisko przetworzonej. W niniejszej publikacji skupiono się na omówieniu przemian, jakim podlegają kwasy nukleinowe w przewodzie pokarmowym człowieka, procesie absorpcji nukleotydów oraz nukleozydów z przewodu pokarmowego, a także przedstawiono podstawowe etapy ich metabolizmu w komórkach organizmu. Produkty trawienia kwasów nukleinowych stanowią...
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Characterization of fatty acid composition in Eurasian badger (Meles meles)
PublicationPolyunsaturated fatty acids (PUFAs, LA and ALA) are not synthesized in mammals in the absence of their essential fatty acid precursors. However, hibernating animals and animals sleeping through the winter need sufficiently high amounts of these acids. The Eurasian badger does not hibernate, but sleeps over winter. In the autumn the body weight of adult badgers increases even twofold, since they put on fat before the winter. Fat...
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Skład i zawartość kwasów tłuszczowych w mleku kobiet z gdańska i okolic w różnych okresach laktacji = Fatty acid composition in breast milk of women from gdańsk and the surrounding district in the course of lactation
PublicationCelem pracy była ocena składu i zawartości kwasów tłuszczowych w tłuszczu mleka kobiet w różnych okresach laktacji, z uwzględnieniem składu KT pokarmu spożywanego przez matki. Do badań zakwalifikowano 80 położnic od których uzyskano próbki mleka w 2, 14, 30 i 90 dobie laktacji. Jednocześnie przeprowadzono badania ankietowe na podstawie których oszacowano zawartość poszczególny grup KT w dziennej racji pokarmowej matek. Skład i...
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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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The reactions of dialkyl phosphites and phosphine oxides with iodosylbenzene
PublicationThe reaction of iodosylbenzene with >P(O)H type of acids (dialkyl phosphites, secondary phosphine oxides) was studied. The acids of >P(O)H type add to iodosylbenzene to yield intermediate 6 which in the aprotic solvents yields oxidation products, it means >P(O)OH acids and/or anhydride of >P(O)OP(O)< type. On the other hand if the reaction is performed in alcohol as a solvent in the presence of sodium alcoholate >P(O)OR ester is...
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The influence of humic substances in treated sewage on the quality of surface waters
PublicationAt present the evaluation of WWTP effectiveness is based upon organic matter and nutrients removal. Recently it was found out that sewage treatment leads to formation of resistant to biochemical degradation organic compounds, similar to humic acids. The humic acids formed during sewage treatment process play diversified functions when discharged to surface waters - for instance they can act as carriers of hydrophobic organic pollutants...
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Treated wasetewater as a source of humic substances in surface waters
PublicationHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Chemical composition of lipids isolated from selected organs and tissues of the raccoon dog (Nyctereutes procyonoides)
PublicationOur paper presents a qualitative analysis of particular lipid classes (phospholipids, triacylglycerols, cholesterol, free fatty acids) isolated from the tissues of raccoon dogs harvested in northeastern Poland. In all examined tissues (except for the liver) the dominant group of lipids were triacylglycerols. The amounts of lipids representing the other classes depended on the kind of tissue from which the fat was isolated. The...
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Ocena wpływu pokarmowych kwasów nukleinowych i ich komponentów na replikacyjną i naprawczą syntezę DNA w modelach komórek ludzkiego układu pokarmowego
PublicationKwasy nukleinowe, do których należą DNA i RNA, są podstawowymi elementami każdej komórki niezbędnymi do prawidłowego funkcjonowania organizmu. Pomimo, że cząsteczki te stanowią również nieodłączne składniki produktów żywnościowych spożywanych przez człowieka, to badania na temat ich zawartości w żywności oraz wartości odżywczej są ograniczone. Wyniki uzyskane w niniejszej pracy doktorskiej pokazały istotne różnice w ilości, wielkości...
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Preparation of Pseudopeptides Building Blocks with Retro-Thioamide Bond Mediated via Thiocarbamoyl Meldrum's Acid
PublicationAn easy and efficient synthesis of pseudo tripeptide containing a thiomalonamide moiety was developed. Isothiocyanate derivatives of amino acids react smoothly with 2,2-dimethyl-1,3-dioxane-4,6-dione yielding new thiocarbamoyl Meldrum's acids. Thermal decomposition of this new Meldrum's acid derivatives generate thiocarbamoyl ketenes, which acylate amino acid esters to give pseudo tripeptides.
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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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Peptide modification with thiomalonoamide moiety
PublicationAbstract: Meldrum acid derivatives under the thermal decomposition are well known source of ketenes. Recently we investigated chemical properties of thiocarbamolyl meldrum acids. We found that 5-(α-alkylamino- α'-sulfhydryl)methylene Meldrum's acids hated in the presence of amines produce thiomalonamides. We used this reaction to the one pot synthesis of series of short peptides containing thiomalonoamide motif.
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Cuticular lipids of insects as potential biofungicides
PublicationThe term ''lipids'' refers to fatty acids, their derivatives and substances related with them biochemically or by the functions in the body. Lipids include compounds with different chemical structure. There are lipids with structures based on long-chain carboxylic acids and their direct derivatives, namely: fatty acids, alkanes, some alkenes, aldehydes and long chain alcohols and their derivatives (esters). The variety of lipid...
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Degradation of xylose using a microbial fuel cell
PublicationIt is generally known, that many kind of microorganisms are capable of using carbohydrates as a source of carbon and energy in an environment. The biodegradation process of monosaccharides from pentoses (in this case- racemic mixture of D - and L – xylose) is an immense opportunity for an entire reduction of biological contamination to neutral compounds through MFC. The process is occurred in a single-chamber MFC, which is contained...
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Phospholipids as potential prevention factor in carcinogenesis
PublicationPhospholipids are a group of complex lipids, which can be used in cancer chemoprevention. Glicerophospholipids are composed of fatty acids esterified to a glycerol backbone, a phosphate group and a hydrophilic residue such as: cho- line, ethanoloamine, serine or inositol. In the sn-2 position of glicerophospholipid usually there are unsaturated fatty acids, i.e. linolenic acid, while in the sn-1 position more typi- cal are saturated...
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Pochodne oleju makowego jako związki biologicznie czynne
PublicationW pracy przebadano skład kwasów tłuszczowych oleju makowego z nasion maku niskomorfinowego (Michałko, Agat, Mieszko, Zambo, Rubin i Przemko) i wysokomorfinowego (Lazur). Do dalszych badań wybrano olej makowy odmiany Michałko ze względu na wysoką zawartość kwasu linolowego (72,8%), niską zawartość kwasu oleinowego (12,6%) i kwasu linolenowego (0,8%). Kwasy nasycone głównie palmitynowy (11,3%) mogą być usunięte w odrębnym postępowaniu....