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SM ISO690:2012 CEACÎRU, Mihail, GONTA, Maria, GUŢU, Iacob, CEACÎRU, Cristina, DUKA, Gh.. Functionalization of chitosane with carboxyl and organic acids. In: The Environment and the Industry: SIMI 2019 Book of abstracts, 26-27 septembrie 2019, București. București, România: National Research and Development Institute for Industrial Ecology ECOIND, 2019, Ediția a 22-a, Book of abstracts, pp. 28-29. ISSN 1843-5831. DOI: https://doi.org/10.21698/simi.2019.ab07 |
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The Environment and the Industry Ediția a 22-a, Book of abstracts, 2019 |
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Conferința "The Environment and the Industry" București, Romania, 26-27 septembrie 2019 | ||||||
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DOI:https://doi.org/10.21698/simi.2019.ab07 | ||||||
Pag. 28-29 | ||||||
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Introduction Chitin occupies second place after cellulose and is among the most widespread Figure 1. The reaction mechanism of chitosan grafting to dihydroxyfumaric acid in 100 ml of 0.5% acetic acid, shake with the magnetic stirrer until the chitosan solubilizes. After that, ascorbic acid (1.10 g) is added and the mixture is heated for 3 hours at 100 ° C. After completion of the reaction time, the mixture is precipitated, filtered, dried under vacuum. Figure 2. Funcționalizarea chitosanului cu acidul ascorbic, raport echimolar, t= 3 h, t= 100 °C that the antiradical power of the functionalized copolymer is 2.5 times higher than pure dihydroxyfumaric acid. These composites are to be used to inhibit the formation of N-nitrosamines in drug-nitrosation. established that the antiradical activity of the copolymer is 16.7% higher than pure ascorbic acid at the same concentration of AAs. It has been demonstrated a functionalization of chitosan with dihydroxyfumaric acid. The antiradical power of the functionalized copolymer was determined. Intermediate and final compounds have been demonstrated by IR, UV and H1-NMR spectra. increasing the antioxidant power of natural reducers.
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Cuvinte-cheie antioxidants, chitosan, dihydroxyfumaric acid, Functionalization |
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<?xml version='1.0' encoding='utf-8'?> <resource xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns='http://datacite.org/schema/kernel-3' xsi:schemaLocation='http://datacite.org/schema/kernel-3 http://schema.datacite.org/meta/kernel-3/metadata.xsd'> <identifier identifierType='DOI'>http://doi.org/10.21698/simi.2019</identifier> <creators> <creator> <creatorName>Ceacîru, M.</creatorName> <affiliation>Universitatea de Stat din Moldova, Moldova, Republica</affiliation> </creator> <creator> <creatorName>Gonţa, M.V.</creatorName> <affiliation>Universitatea de Stat din Moldova, Moldova, Republica</affiliation> </creator> <creator> <creatorName>Guţu, I.E.</creatorName> <affiliation>Universitatea de Stat din Moldova, Moldova, Republica</affiliation> </creator> <creator> <creatorName>Ceacîru, C.</creatorName> <affiliation>Universitatea de Stat din Moldova, Moldova, Republica</affiliation> </creator> <creator> <creatorName>Duca, G.G.</creatorName> <affiliation>Institutul de Chimie, Moldova, Republica</affiliation> </creator> </creators> <titles> <title xml:lang='en'>Functionalization of chitosane with carboxyl and organic acids</title> </titles> <publisher>Instrumentul Bibliometric National</publisher> <publicationYear>2019</publicationYear> <relatedIdentifier relatedIdentifierType='ISBN' relationType='IsPartOf'></relatedIdentifier> <subjects> <subject>antioxidants</subject> <subject>chitosan</subject> <subject>dihydroxyfumaric acid</subject> <subject>Functionalization</subject> </subjects> <dates> <date dateType='Issued'>2019</date> </dates> <resourceType resourceTypeGeneral='Text'>Conference Paper</resourceType> <descriptions> <description xml:lang='en' descriptionType='Abstract'><p>Introduction</p><p>Chitin occupies second place after cellulose and is among the most widespread<br />biopolymers in nature. Chitosan (made from chitin) is a versatile biopolymer and<br />therefore its derivatives are used in various fields such as agriculture, food industry,<br />cosmetics, water treatment and so on. Chitosan is also of interest in the pharmaceutical<br />field because it is biodegradable, biocompatible and has a low toxicity.<br />The main objective of this paper was the synthesis of some derivatives of chitosan<br />functionalized with dihydroxyfumaric acid and ascorbic acid.<br />Materials and methods<br />Chitosan – dihydroxyfumaric (Cht-DFH4) was prepared in 3 phase. In first phase<br />chitosan – diacetyl tartaric anhydride (C) was prepared according to the method<br />described by Chen et al (2013) with some modifications, following the interaction of<br />chitosan (B) with diacetyl tartaric anhydride (A). In second phase hydrolysis is carried<br />out with NaOH (D), and after consumption of the base, the mixture is filtered, washed<br />with acetone and dried. The obtained copolymer (E) is used to oxidize the step with<br />the Fenton reagent to obtain the chitosan grafted with dihydroxyfumaric acid (F).<br />The functionalisation of chitosan was performed according to the figure 1:</p><p>Figure 1. The reaction mechanism of chitosan grafting to dihydroxyfumaric acid<br />Chitosan ascorbate (Cht-AAs) was prepared according to the method described by<br />Hafsa et al (2014) with some modifications. Weigh out 1.00 g of chitosan and dissolve</p><p>in 100 ml of 0.5% acetic acid, shake with the magnetic stirrer until the chitosan solubilizes.</p><p>After that, ascorbic acid (1.10 g) is added and the mixture is heated for 3 hours at 100 ° C.</p><p>After completion of the reaction time, the mixture is precipitated, filtered, dried under</p><p>vacuum.<br />The mechanism of reaction between chitosan and ascorbic acid is represented in Schemes 2.</p><p>Figure 2. Funcționalizarea chitosanului cu acidul ascorbic, raport echimolar, t= 3 h, t= 100 °C<br />Results and conclusions<br />The anti-oxidant activity Cht-DFH4 was determined by the DPPH test and it has been established</p><p>that the antiradical power of the functionalized copolymer is 2.5 times</p><p>higher than pure dihydroxyfumaric acid. These composites are to be used to inhibit the</p><p>formation of N-nitrosamines in drug-nitrosation.<br />The anti-oxidant activity Cht-AAs was determined by the ABTS test and it has been</p><p>established that the antiradical activity of the copolymer is 16.7% higher than pure</p><p>ascorbic acid at the same concentration of AAs.<br />Table 1.Total antioxidant activity (ABTS • +) of the composite and pure AAs after</p><p>It has been demonstrated a functionalization of chitosan with dihydroxyfumaric acid.</p><p>The antiradical</p><p>power of the functionalized copolymer was determined. Intermediate and final</p><p>compounds have been demonstrated by IR, UV and H1-NMR spectra.<br />Chitosan was functionalized with dihydroxyfumaric acid and ascorbic acid,</p><p> increasing the antioxidant power of natural reducers.</p><p> </p></description> </descriptions> <formats> <format>application/pdf</format> </formats> </resource>