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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">medlit</journal-id><journal-title-group><journal-title xml:lang="ru">Гигиена и санитария</journal-title><trans-title-group xml:lang="en"><trans-title>Hygiene and Sanitation</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0016-9900</issn><issn pub-type="epub">2412-0650</issn><publisher><publisher-name>Federal Scientific Center of Hygiene named after F.F. Erisman</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.47470/0016-9900-2022-101-5-567-571</article-id><article-id custom-type="elpub" pub-id-type="custom">medlit-2278</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>МЕТОДЫ ГИГИЕНИЧЕСКИХ ИССЛЕДОВАНИЙ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>METHODS OF HYGIENIC AND EXPERIMENTAL INVESTIGATIONS</subject></subj-group></article-categories><title-group><article-title>Методика выделения ДНК из образцов почвы</article-title><trans-title-group xml:lang="en"><trans-title>The method of DNA extraction from soil samples</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3554-7690</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ракитина</surname><given-names>Д. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Rakitina</surname><given-names>Darya V.</given-names></name></name-alternatives><email xlink:type="simple">noemail@neicon.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/0000-0002-5282-3856</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Асланова</surname><given-names>М. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Aslanova</surname><given-names>Mariya M.</given-names></name></name-alternatives><email xlink:type="simple">noemail@neicon.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/0000-0002-6295-661X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мания</surname><given-names>Тамари Резоевна</given-names></name><name name-style="western" xml:lang="en"><surname>Maniya</surname><given-names>Tamari R.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Науч. сотр. лаб. микробиологии и паразитологии ФГБУ «ЦСП» ФМБА России, 119121, Москва.</p><p>e-mail: TManiya@cspmz.ru</p></bio><bio xml:lang="en"><p>Researcher of Microbiology and Parasitology laboratory of the Centre for Strategic Planning and Management of Biomedical Health Risks of the Federal Medical Biological Agency, Moscow, 119121, Russian Federation.</p><p>e-mail: TManiya@cspmz.ru</p></bio><email xlink:type="simple">tmaniya@cspmz.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБУ «Центр стратегического планирования и управление медико-биологическими рисками здоровью» Федерального медико-биологического агентства</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Centre for Strategic Planning and Management of Biomedical Health Risks of the Federal Medical Biological Agency</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>07</day><month>06</month><year>2022</year></pub-date><volume>101</volume><issue>5</issue><fpage>567</fpage><lpage>571</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ракитина Д.В., Асланова М.М., Мания Т.Р., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Ракитина Д.В., Асланова М.М., Мания Т.Р.</copyright-holder><copyright-holder xml:lang="en">Rakitina D.V., Aslanova M.M., Maniya T.R.</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.rjhas.ru/jour/article/view/2278">https://www.rjhas.ru/jour/article/view/2278</self-uri><abstract><sec><title>Введение</title><p>Введение. Даже в городских условиях человек находится в постоянном контакте с почвой как объектом окружающей среды. При этом с почвенным загрязнением могут переноситься различные патогены, в том числе и опасные для животных и человека. В связи с этим остро стоит вопрос разработки методик для совершенствования мониторинга таких патогенных объектов. Метод ПЦР широко применяется в лабораторной практике, позволяя выявить и некультивируемые типы патогенов.</p><p>Цели и задачи — подобрать методику эффективного выделения из почвенных образцов ДНК, пригодной для проведения ПЦР-анализа.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Выделение ДНК из образцов поверхностного слоя дерново-подзолистого грунта проводили с использованием как химических реактивов, так и готовых коммерческих (но не специализированных) наборов. ПЦР-анализ проводили методом детекции в режиме реального времени.</p></sec><sec><title>Результаты</title><p>Результаты. Проанализировано четыре основных метода выделения ДНК из почвы в различных сочетаниях друг с другом и с тремя видами предварительной и постобработки. Хотя ДНК выделялась из почвы всеми методами, но без дополнительной очистки она была непригодна для постановки ПЦР. Показана необходимость обработки образцов солями кальция для удаления гуминовых кислот, ингибирующих ПЦР. В результате выбраны два метода выделения ДНК из почвы. В обоих первые стадии сочетали метод с использованием бромида цетримония (CTAB) и предобработку CaCO3. Более чувствительный и более дешёвый метод предполагает на третьей стадии постобработку CaCl2. Другой метод сильно уступает в чувствительности, но выигрывает в воспроизводимости, при его использовании третья стадия включает очистку на колонках из набора Qiagen.</p></sec><sec><title>Ограничения исследования</title><p>Ограничения исследования. При отработке методики выделения ДНК для ПЦР-анализа были изучены образцы только одного типа почв — дерново-подзолистого грунта. Поэтому методика может быть применена только для этого типа почв.</p></sec><sec><title>Заключение</title><p>Заключение. Разработанные методы применимы при оценке с применением метода ПЦР загрязнённости почв дерново-подзолистого типа патогенными организмами.</p></sec><sec><title>Участие авторов</title><p>Участие авторов: Ракитина Д.В. — концепция и дизайн исследования, отбор образцов, написание текста, выделение ДНК и ПЦР-анализ;Асланова М.М. — концепция и дизайн исследования, отбор образцов, написание текста;Мания Т.Р. — редактирование.Все соавторы — утверждение окончательного варианта статьи, ответственность за целостность всех частей статьи.</p></sec><sec><title>Конфликт интересов</title><p>Конфликт интересов. Авторы декларируют отсутствие явных и потенциальных конфликтов интересов в связи с публикацией данной статьи.</p></sec><sec><title>Финансирование</title><p>Финансирование. Исследование проведено в рамках НИР «Разработка унифицированных методов, включающих отбор проб, для осуществления определения микробиологического и паразитологического загрязнения сточных вод» (шифр «Сточные воды») АААА-А21-121011190012-3.</p></sec><sec><title>Поступила</title><p>Поступила: 09.02.2022 / Принята к печати: 21.04.2022 / Опубликована: 31.05.2022</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Even in the modern urban environment humans are in constant direct and indirect contact with soil. This leads to the spread of a wide range of soil-transmitted human and animal pathogens. Therefore, the development of fast and inexpensive methods of analysis and monitoring of these pathogenic objects is of great importance. PCR method is widely applied in laboratory practice and is able to detect even the uncultivated types of pathogens. </p><p>The aim of the study was to optimize the method of DNA isolation from soil, making it suitable for PCR-assay. </p></sec><sec><title>Materials and methods</title><p>Materials and methods. DNA was isolated from the samples of surface layer of forest soil rich in humus, using lab-shelf chemicals and/or commercial kit. RT-PCR-test was performed using universal bacterial primers. </p></sec><sec><title>Results</title><p>Results. We have analyzed various combinations of four extraction methods and three pre- and post-treatment methods. DNA was efficiently extracted by all methods, however, without additional purification stages it was unsuitable for PCR. The calcium salts treatment ws demonstrated to be necessary for removal of PCR inhibitors, presumably humic acids. Two DNA isolation methods were developed. Both methods use incubation with CaCO3 suspension followed by cetrimonium bromide lysis. More sensitive and unexpensive method uses CaCl2 as an additional purification stage. The less sensitive but more reproducible method included DNA isolation on Qiagen DNA (Qiagen) columns. </p></sec><sec><title>Limitations</title><p>Limitations. When working out the technique of DNA isolation for PCR analysis, samples of the only sod-podzolic soil were studied. Therefore, the technique can be applied only for this type of soil. </p></sec><sec><title>Conclusion</title><p>Conclusion. Both methods optimized in this study can be used for evaluation of soil samples for the presence of pathogens by PCR. </p></sec><sec><title>Contribution</title><p>Contribution:Rakitina D.V. — concept and design of research, sampling, writing text, DNA isolation and PCR analysis.Aslanova M.M. — concept and design of research, sampling, writing text.Maniya T.R. — editing.All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.</p></sec><sec><title>Conflict of interest</title><p>Conflict of interest. The authors declare no conflict of interest.</p></sec><sec><title>Acknowledgment</title><p>Acknowledgment. The research was carried out within the framework of the research work «Development of unified methods, including sampling, for the determination of microbiological and parasitological contamination of wastewater” (code “Wastewater”) No. 145.001.21.6 dated 12.11.2021.</p></sec><sec><title>Received</title><p>Received: February 02, 2022 / Accepted: April 21, 2022 / Published: May 31, 2022</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>почва</kwd><kwd>ДНК</kwd><kwd>ПЦР</kwd><kwd>кальций</kwd><kwd>CTAB</kwd></kwd-group><kwd-group xml:lang="en"><kwd>soil</kwd><kwd>DNA</kwd><kwd>PCR</kwd><kwd>calcium</kwd><kwd>CTAB</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Steffan J.J., Derby J.A., Brevik E.C. Soil pathogens that may potentially cause pandemics, including severe acute respiratory syndrome (SARS) coronaviruses. Curr. Opin. Environ. Sci. 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