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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">vguit</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Воронежского государственного университета инженерных технологий</journal-title><trans-title-group xml:lang="en"><trans-title>Proceedings of the Voronezh State University of Engineering Technologies</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-910X</issn><issn pub-type="epub">2310-1202</issn><publisher><publisher-name>VSUET</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.20914/2310-1202-2023-2-247-255</article-id><article-id custom-type="elpub" pub-id-type="custom">vguit-3319</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Химическая технология</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Fundamental and Applied chemistry, chemical technology</subject></subj-group></article-categories><title-group><article-title>Синтез и исследование композитных материалов на основе яблочного пектина и катионов меди</article-title><trans-title-group xml:lang="en"><trans-title>Synthesis and study of composite materials based on apple pectin and copper cations</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0004-1375-1054</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мамедов</surname><given-names>Э. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Mamedov</surname><given-names>E. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>аспирант, кафедра физического металловедения, ул. Московская, 30, г. Липецк, 398055, Россия</p></bio><bio xml:lang="en"><p>graduate student, physical metallurgy department, Moskovskaya Av., 30, Lipetsk, 398055, Russia</p></bio><email xlink:type="simple">elik.mam@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2841-6126</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кольцов</surname><given-names>В. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Koltsov</surname><given-names>V. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>канд. с.-х. наук, старший научный сотрудник, лаборатория передовых послеуборочных технологий, ул. Мичурина, 30, г. Мичуринск, 393774, Россия</p></bio><bio xml:lang="en"><p>Cand. Sci. (Agric.), senior reseacher, laboratory of advanced post-harvest technologies, Michurina Av., 30, Lipetsk, 393774, Russia</p></bio><email xlink:type="simple">kolcov.mich@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Калмыкова</surname><given-names>Е. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Kalmykova</surname><given-names>E. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>д-р хим. наук, доцент, кафедра химии, ул. Московская, 30, г. Липецк, 398055, Россия</p></bio><bio xml:lang="en"><p>Dr. Sci. (Chem.), associate professor, сhemistry department, Moskovskaya Av., 30, Lipetsk, 398055, Russia</p></bio><email xlink:type="simple">veter1407@rambler.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Липецкий государственный технический университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Lipetsk State Technical University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Федеральный научный центр им. И.В. Мичурина</institution><country>Russian Federation</country></aff><aff xml:lang="en"><institution>Federal Scientific Center. I.V. Michurin</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>02</day><month>09</month><year>2023</year></pub-date><volume>85</volume><issue>2</issue><fpage>247</fpage><lpage>255</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Мамедов Э.И., Кольцов В.А., Калмыкова Е.Н., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Мамедов Э.И., Кольцов В.А., Калмыкова Е.Н.</copyright-holder><copyright-holder xml:lang="en">Mamedov E.I., Koltsov V.A., Kalmykova E.N.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.vestnik-vsuet.ru/vguit/article/view/3319">https://www.vestnik-vsuet.ru/vguit/article/view/3319</self-uri><abstract><p>В работе представлены результаты синтеза металлокомпозитных материалов на основе яблочного пектина и катионов двухвалентного металла – Cu2+; определения степени этерификации и содержания свободных карбоксильных групп исходного пектина методом кислотно-основного титрования, определения степени включения указанного катиона в полисахаридную макромолекулу методом ИК-спектроскопии, а также фунгицидной активности исходного пектина и медных комплексов в отношении Penicillum sp. По результатам титрования установлено, что яблочный пектин обладает высокой степенью этерификации (СЭ = 50,7 %) и низким содержанием карбоксильных групп (Кс = 2,79 %), что предполагает его низкую желирующую активность. Установлено, что увеличение концентрации соли выше 0,005 г-экв/л. приводит к снижению доли получающегося водорастворимого комплекса. Оптимальное значение концентрации CuSO4·5H2O, при которой образуется наибольшая масса водорастворимого комплекса, составляет 0,005 г-экв/л. По данным ИК-спектроскопии произведен расчет степени замещения катионов натрия на катионы меди, которая составила 18 %. Показано, что исходный яблочный пектин не обладает фунгицидной активностью, в то время как медный комплекс на его основе способен подавлять рост культуры уже при действии 10 мкл вещества, а при увеличении объема до 50 мкл проявляется еще более активная фунгицидная активность медного комплекса.</p></abstract><trans-abstract xml:lang="en"><p>The paper presents the results of synthesis the metal-composite materials based on apple pectin and divalent metal cations - Cu2+; determining the degree of esterification and the content of free carboxyl groups of the native pectin by acid-base titration, determining the degree of inclusion of the specified cation in the polysaccharide macromolecule and studying by IR spectroscopy and fungicidal activity of native pectin and copper complexes against Penicillum sp According to the results of titration, it was found that apple pectin has a high degree of esterification (DE = 50.7%) and a low content of carboxyl groups (Kc = 2.79%), which suggests its low gelling activity. It was found that the increase in salt concentration is above 0.005 g-eq/l. leads to a decrease in the proportion of the resulting water-soluble complex. The optimal concentration of CuSO4 5H2O, at which the largest mass of the water-soluble complex is formed, is 0.005 g-eq/l. According to IR spectroscopy, the degree of substitution of sodium cations for copper cations was calculated, which amounted to 18%. It was shown that the native apple pectin does not have fungicidal activity, while the copper complex based on it is able to suppress the growth of the culture already under the action of 10 µl of the substance, and with an increase in volume to 50 µl, an even more active fungicidal activity of the copper complex appears.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>пектин</kwd><kwd>металлокомплекс</kwd><kwd>степень замещения</kwd><kwd>ИК-спектроскопия</kwd><kwd>кислотно-основное титрование</kwd><kwd>противогрибковая активность</kwd></kwd-group><kwd-group xml:lang="en"><kwd>pectin</kwd><kwd>metal complex</kwd><kwd>degree of substitution</kwd><kwd>IR spectroscopy</kwd><kwd>acid-base titration</kwd><kwd>antifungal activity</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">ОГБУ «Липецкая областная ветеринарная лаборатория»</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Bush P.L. 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