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101.
Dorota Bederska-ojewska Marek Pieszka Aleksandra Marzec Magdalena Rudziska Anna Grygier Aleksander Siger Katarzyna Cielik-Boczula Sylwia Orczewska-Dudek Wadysaw Migda 《Molecules (Basel, Switzerland)》2021,26(24)
Every year, thousands of tons of fruit seeds are discarded as agro-industrial by-products around the world. Fruit seeds are an excellent source of oils, monounsaturated fatty acids, and n-6 and n-3 polyunsaturated essential fatty acids. This study aimed to develop a novel technology for extracting active substances from selected seeds that were obtained after pressing fruit juices. The proposed technology involved sonification with the use of ethyl alcohol at a low extraction temperature. Seeds of four species—blueberry (Vaccinium myrtillus L.), raspberry (Rubus idaeus), cranberry (Vaccinium macrocarpon), and cuckooflower (Cardamine pratensis)—were used for extraction. Following alcohol evaporation under nitrogen, the antioxidant activity, chemical composition, and volatile compounds of the obtained extracts were analyzed using chromatographic methods, including gas chromatography (GC)–mass spectrometry (MS) (GC–MS/MS), and high-performance liquid chromatography–MS. We analyzed physicochemical properties, fatty acid, and volatile compounds composition, sterol and tocochromanol content of blueberry, cranberry, raspberry, and cuckooflower seed oils obtained by sonication. This method is safe and effective, and allows for obtaining valuable oils from the seeds. 相似文献
102.
Minar Mahmoud M. Hassanein Adel Gabr Abdel-Razek Sherine Mohamed Affifi Ying Qian Elbieta Radziejewska-Kubzdela Aleksander Siger Magdalena Rudziska Ghada Ahmed Abo-Elwafa Anna Grygier 《Molecules (Basel, Switzerland)》2022,27(23)
The purpose of this study was to explore the effects of roasting linseeds on the pigment, lipid profile, bioactive components, and oxidative stability of the extracted oils. The linseed varieties Giza 11, Giza 12, Sakha 3, and Sakha 6 were roasted at 180 °C for 10 min, and the oils were extracted by cold pressing. The results showed that, after roasting, there was an increase in oil percentage and peroxide value, as well as small increases in p-anisidine and acid values. Roasting also caused an increase in chlorophyll content, while lutein and β-carotene tend to slightly decrease, except in the Giza 11 variety. The total phenolics content was markedly enhanced after roasting. Omega-3 fatty acids were not affected by the roasting process. The total amounts of tocochromanol were found to decrease in the Giza 12 and Sakha 6 varieties after roasting. Plastochromanol-8 increased in all varieties after roasting. The phytosterol composition was minimally affected by roasting. Roasting enhanced the stability of the extracted oils, increasing the induction period and decreasing EC50 values. These results may thus help to discriminate between the different linseed varieties and serve to recommend the use of roasting to enhance the oxidative stability of extracted oil. 相似文献
103.
Leen V Miscoria D Yin S Filarowski A Ngongo JM Van der Auweraer M Boens N Dehaen W 《The Journal of organic chemistry》2011,76(20):8168-8176
1,7-Dihalogenated boron dipyrromethene dyes were successfully synthesized and substituted, thus providing an entry to the final, elusive reactivity pattern. The spectroscopic properties of 1,7-disubstituted BODIPY dyes were studied and are discussed as a function of their structure. 相似文献
104.
Barbara Bartoś Barbara Filipowicz Monika Łyczko Aleksander Bilewicz 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):513-516
Dynamic adsorption of radiocesium on titanium ferrocyanide grains from reactor coolant simulating solution containing salts at moderate concentrations has been investigated. Effective decontamination of the neutral solutions has been achieved, in the amounts of a more than 20 thousand bed volumes. After adsorption the titanium ferrocyanide was transferred to titanates and calcined at 900 °C. The leaching test of the obtained lithium titanates indicates that the loaded adsorbent can serve as an effective primary barrier in nuclear waste repositories. 相似文献
105.
106.
Every finite disconnected set P is determined (up to automorphism) by the family {P − {a}:a ∈ Max
P
}. 相似文献
107.
108.
Cinnamonitrile as a precursor of a bi-centered electrophile in reactions with arenes in triflic acid
Yelizaveta Gorbunova Dmitriy N. Zakusilo Aleksander V. Vasilyev 《Tetrahedron letters》2019,60(14):961-964
The reaction of cinnamonitrile [PhCH?=?CHCN] with arenes in the superacid TfOH at room temperature for 1?h gave two types of compounds, 3-aryl-3-phenyl propionitriles [Ar(Ph)CHCH2CN] and/or 3-phenylindanones in 28–76% yield. The formation of these two reaction products depends on the nucleophilicity of the arene. In these reactions, carbocations generated upon the protonation of cinnamonitrile in TfOH behave as bi-centered electrophiles possessing reactive centers on the C3 carbon of the double bond and on the C1 carbon of the nitrile group. 相似文献
109.
Aleksander Ivanov 《Mathematical Logic Quarterly》2015,61(4-5):307-314
We analyse ω‐categorical precompact expansions of particular ω‐categorical structures from the viewpoint of amenability of their automorphism groups. 相似文献
110.