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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'?> <oai_dc:dc xmlns:dc='http://purl.org/dc/elements/1.1/' xmlns:oai_dc='http://www.openarchives.org/OAI/2.0/oai_dc/' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:schemaLocation='http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd'> <dc:creator>Ceacîru, M.</dc:creator> <dc:creator>Gonţa, M.V.</dc:creator> <dc:creator>Guţu, I.E.</dc:creator> <dc:creator>Ceacîru, C.</dc:creator> <dc:creator>Duca, G.G.</dc:creator> <dc:date>2019</dc:date> <dc:description xml:lang='en'><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></dc:description> <dc:identifier>http://doi.org/10.21698/simi.2019</dc:identifier> <dc:source>The Environment and the Industry (Ediția a 22-a, Book of abstracts) 28-29</dc:source> <dc:subject>antioxidants</dc:subject> <dc:subject>chitosan</dc:subject> <dc:subject>dihydroxyfumaric acid</dc:subject> <dc:subject>Functionalization</dc:subject> <dc:title>Functionalization of chitosane with carboxyl and organic acids</dc:title> <dc:type>info:eu-repo/semantics/article</dc:type> </oai_dc:dc>