Перегляд за Автор "Kovaleva, Svetlana"

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Chemical resistance of sunflower oil enriched with cumin oil
(2020) Podobiy, Olena; Kovaleva, Svetlana; Zhytnetskyi, Ihor; Mayboroda, Elena
Антиоксидантні властивості олії кмину використовуються для гальмування руйнівних процесів в соняшниковій олії. Досліджено хімічну стійкість соняшникової олії та суміші соняшникової олії та олії кмину. Йодне число олій знижується під час смаження, що означає руйнування подвійних С-С зв’язків залишку жирних кислот у молекулах тригліцеридів. Природні антиоксиданти в олії кмину гальмують утворення вторинних продуктів окиснення під час смаження. Змішування соняшникової олії з олією кмину позитивно впливає на хімічну стійкість масляних композицій в умовах нагрівання. The antioxidant properties ofcumin oil are used to inhibit destructive processes in sunflower oil. The chemical resistanse of sunflower oil and f mixtures of sunflower oil and cumin seed oil was studied. The iodine value of oils decreases during frying, that means a destruction double C-C bonds of fatty acids residue in triglyceride molecules. Natural antioxidants in cumin oil have an inhibitory effect on the formation of secondary oxidation products during frying terms. Blending sunflower oil with cumin oil leads to a positive effect on the chemical resistance of oil compositions under heating conditions.
Determination of Fatty Acid Profile of Sunflower Oil Samples by NMR 1H Spectroscopy
(2018) Kovaleva, Svetlana; Mazur, Larisa; Miroshnikov, Oleg; Hutsalo, Inna
Sunflower oil with a high content of oleic acid (Omega-9) and a sufficiently low content of polyunsaturated linoleic acid (Omega-6) is characterized by a lower nutritional value but greater chemical stability at high temperatures and in the presence of oxidizing agents, therefore, it has several advantages for the food and chemical industries, and also as a raw material for the production of biofuels. The determination of the TAG composition o f oil is very important, because due to selection there is a large number o f sunflower varieties. The spectra o f oil samples extracted from seeds o f various sunflower varieties were investigated by NMR 1H spectroscopy to determine fatty acids composition. This method based on estimation and comparison the proton integral intensities of allylic and bis-allylic CH2 groups with intensity o f glycerol protons that allows to determine the amounts o f these unsaturated fatty acids. Each oil sample obtained has its individual TAG profile determining its physicochemical properties and nutritional value. Method 1H-NMR spectroscopy is rapid and non-destructive, so it is perspective for determination o f oil fatty acid composition.
Determination of fatty acids profile of sunflower oil samples by NMR 1H spectroscopy
(2018) Kovaleva, Svetlana; Mazur, Larisa; Hutsalo, Inna
Determination of oleic acid in the samples of sunflower seeds by method of NIR spectroscopy
(2017) Hutsalo, Inna; Mank, Valeriy; Kovaleva, Svetlana
Seed samples of various sunflower varieties with a known content of oleic acid and the same samples additionally enriched with oleic acid were investigated by NIR diffusion reflectance spectroscopy. This non-destructive NIRS method could simplify the analysis of qualitative components, because of the low level of light absorption in this spectral region. The express method of diffuse reflectance NIR spectroscopy can be considered as an alternative method for determining the quality of fat-containing materials in the processes o f their storage, sorting or processing.
Determination of presence of the water-retainer sodium triphosphate in minced meat with method of near-IR spectroscopy
(2017) Melnichenko, Georgii; Hutsalo, Inna; Kovaleva, Svetlana
Addition of sodium triphosphate (E451) to meat semi-finished products improves the moisture-absorbing properties of muscle tissue, but worsens the absorption of calcium by human body. Therefore, content of sodium triphosphate must be controled. This express method of non-destructive IR spectroscopy, provided that the spectrograph has been pre-calibrated, allows to detect objectively the presence o f sodium triphosphate (E451) in minced meat.
Determination of raw meat freshness by the express method of n ear-IR spectroscopy
(2017) Volkov, A.; Litvynchuk (Vorontsova), Svitlana; Kovaleva, Svetlana
When raw meat is stored for a long time, many biochemical processes take place inside. As result, new substances, that not typical for fresh meat, are formed. Present of these compounds may be identified by near-IR spectroscopy. If the spectrograph is pre-calibrated, the express method of nondestructive near-IR spectroscopy can be used for objective estimate o f degree o f meat freshness. The use of this method allows to avoid errors in estimation that typical for organoleptic methods.
Determination of Sunflower Oil Oxidation Products by NMR 1H Spectroscopy
(2017) Kovaleva, Svetlana; Mazur, Larisa
Electron-Rich Amino Heterocycles for Regiospecific Synthesis of Trifluoromethyl-Containing Fused Pyridines
(2003) Volochnyuk, Dmitriy; Pushechnikov, Alexei; Krotko, Dmitriy; Sibgatulin, Dmitriy; Kovaleva, Svetlana; Tolmachev, Andrei
The reaction of 4,4,4-trifluoro-3-oxobutanoates with the corresponding electron-rich amino heterocycles was investigated. A simple and flexible general procedure for the regiospecific annulation of the trifluoromethylpyridine ring to electron-rich amino heterocycles was proposed. A set of CF3-containing fused pyridines in almost quantitative yield was obtained.
Fructose-inulooligosaccharide syrops exstraction from chicory
(2016) Popova, Inna; Kovaleva, Svetlana; Shulga, Sergii
Obtaining fructose-inulooligosaccharide syrups from fresh roots or dry powder of chicory for the purpose of its further use in the production of healthy food products.
Investigation of chemical transformations in corn oil during the heat treatment
(2020) Korobka, Yuliya V.; Kovaleva, Svetlana
NMR 'H Spectroscopy for Determination of Oxidation Products in Sunflower Oil
(2018) Nikolayenko, Bogdana; Pashkevych, Maksym; Kovaleva, Svetlana
NMR 'H Spectroscopy for the Study of Fatty Acids Composition of Sunflower Oil
(2018) Korobka, Yuliya V.; Kovaleva, Svetlana
Novel approaches to fused phospha-pyrimidines
(2006) Volochnyuk, Dmitriy; Kovaleva, Svetlana; Chernega, Alexandr; Chubaruk, Nataliya; Kostyuk, Alexandr Nik.; Pinchuk, Alexander; Tolmachev, Andrei; Schmutzlerc, Reinhard
Simple methods for the preparation of phosphorus-containing fused pyrimidine analogues such as fused 1,5,2-diazaphosphinines from amidine derivatives of p-excessive heterocycles are described. The scope and limitations of the methodology are detailed. Описано прості методи одержання фосфоровмісних конденсованих аналогів піримідіну, таких як анельовані 1,5,2-діазафосфініни з амідінових похідних електронозбагачених гетероциклів. Деталізовані обмеження застосування.
Phosphorylation of 2-(3-Methyl-1,3-diazabuten-1-yl)-3-Ethoxycarbonylthiophenes with Phosphorus(III) Halides
(2001) Pinchuk, Alexander; Kovaleva, Svetlana; Ivonin, S.; Merkulov, A.; Kudrya, Tamara; Chaikovskaya, Alexandra; Tolmachev, Andrei
Method of selective C5-phosphorylation of derivatives of 2-amino-3-ethoxycarbonylthiophene containing N,N-dimethylformamidine gpoup at the 2nd position of the heterocycle was affered. Derivatives of 2-(3-methyl-1,3-diazabuten-1-yl)-3-ethoxycarbonylthiophene were studied in reactions with Phosphorus(III) Halides. Based on C5-phosphorylated N,N-dimethylamino-N’-(2-thienyl)formamidines the methods for synthesis of new and biologically promising C-phosphorylated derivatives of 2-amino-3-thiophenecarboxylic acids and thieno[2,3-b]pyrimidones were elaborated. Запропоновано метод селективного С5-фосфорилювання галогенідами фосфору (III) похідних 2-аміно-3-етиксикарбонілтіофену, що містять N,N-диметилформамідиновий залишок біля С2-атому гетероциклу. На основі С5-фосфорильованих N,N-диметиламіно-N’-(2-тієніл)формамідинів розроблені методи синтезу невідомих раніше та перспективних в біологічному плані С-фосфорильованих похідних 2-аміно-3-тіофенкарбонових кислот та тієно[2,3-b]піримідонів.
Production technology of sugarglycerides (food additive E474)
(2019) Korobka, Yuliya V.; Haletiy, Olga; Kovaleva, Svetlana
Study of chemical transformations in sunflower oil during heat treatment by NMR 1H spectroscopy
(2019) Korobka, Yuliya V.; Pashkevych, Maksym; Kovaleva, Svetlana
Synthesis of 1,2-dihydrothieno-1λ5-[2,4,1]oxazaphosphine
(2018) Kovaleva, Svetlana; Mazur, Larisa; Zinchenko, Natalia
Synthesis of Dihydropyrimidine Derivatives by Biginelli's Reaction in student Workshops on Organic Chemistry
(2017) Simurova, Natalia; Kovaleva, Svetlana; Mazur, Larisa
In classical student workshops, the attention paid to the synthesis of heterocyclic compounds is very little. This is due to the complexity and duration of most of these syntheses, the low availability of the initial reagents, the difficult isolation and purification the reaction products. Biginelli's reaction, as a method of synthesis of dihydropyrimidones, is attractive to be used in the student workshop on chemistry due to the simple procedure of synthesis, as well as a possibility to vary the reaction conditions and select initial reagents to introduce substituents that may be easily transformed to various functional groups.. Students cannot only get acquainted with the basic experimental methods, but also learn how to apply theoretical knowledge in practice, including monitoring of reactions and analyzing organic compounds by physico-chemical methods.
Synthesis of Six-Membered Thiophene-Annelated Heterocycle Containing P and N atoms
(2017) Kovaleva, Svetlana; Simurova, Natalia; Mazur, Larisa
The Study of the Fatty Acids Composition of Domestic Brands of Sunflower Oil by NMR 1H Spectroscopy
(2017) Kovaleva, Svetlana; Hutsalo, Inna