34 research outputs found

    Hydrolysis of tannic acid catalyzed by immobilized-stabilized derivatives of tannase from Lactobacillus plantarum

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    A recombinant tannase from Lactobacillus plantarum, overexpressed in Escherichia coli, was purified in a single step by metal chelate affinity chromatography on poorly activated nickel supports. It was possible to obtain 0.9 g of a pure enzyme by using only 20 mL of chromatographic support. The pure enzyme was immobilized and stabilized by multipoint covalent immobilization on highly activated glyoxyl agarose. Derivatives obtained by multipoint and multisubunit immobilization were 500- and 1000-fold more stable than both the soluble enzyme and the one-point-immobilized enzyme in experiments of thermal and cosolvent inactivation, respectively. In addition, up to 70 mg of pure enzyme was immobilized on 1 g of wet support. The hydrolysis of tannic acid was optimized by using the new immobilized tannase derivative. The optimal reaction conditions were 30% diglyme at pH 5.0 and 4 C. Under these conditions, it was possible to obtain 47.5 mM gallic acid from 5 mM tannic acid as substrate. The product was pure as proved by HPLC. On the other hand, the immobilized biocatalyst preserved >95% of its initial activity after 1 month of incubation under the optimal reaction conditionsThis work was supported by Grants AGL2008-01052, AGL-2009-07625, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD(CICYT),RM2008-00002 (INIA), and S-0505/AGR/000153 (CAM). J.A.C. is the recipient of a predoctoral fellowship from the I3P-CSIC Program and FPI-MEC, and G.F.-L. and L.B. are recipients of Ramon y Cajal postdoctoral contracts.Peer reviewe

    Биогеохимические исследования урбанизированных ландшафтов восточной Финляндии

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    Объектом исследования являются урбанизированные ландшафты трех городов Восточной Финляндии г. Юука, г. Оутокумпу, г. Миккели. Цель работы - биогеохимические исследования урбанизированных ландшафтов восточной Финляндии по результатам исследования проб почв, листьев и стеблей черники, лишайника, листьев древесных растений. В процессе исследования проводились обзор и анализ ранее проведенных работ, анализы литературных, нормативных и фондовых источников, анализировались статистических данные и элементный состав комплекса природных сред. В результате исследования была изучена геоэкологическая обстановка урбанизированных территорий Восточной Финляндии Степень внедрения результатов: полученный анализ эколого-геохимической ситуации урбанизированных территорий Финляндии является составной частью комплексного эколого-геохимического мониторинга территорий, проводимого кафедрой ГЭГХ ТПУ. Аналитический материал будет использован в учебном процессе. Область применения: результаты эколого-геохимического мониторинга урбанизированных территорий Финляндии могут быть использованы природоохранными организациями для ориентировочных данных по содержанию химических элементов в почвах и живых объектах городских агломераций.Object of research are urban landscapes of the three cities in the Eastern Finland city of Juuka, in Outokumpu, the city of Mikkeli. Purpose - biogeochemical studies of the urban landscape of Eastern Finland the results of the research of samples of soil, leaves and stems of bilberry, lichen, leaves of woody plants. In the process of investigation the review and analysis of earlier conducted works, literary analyses, regulatory and archival sources, analyzed statistical data and elemental composition of complex natural environments. The study was studied geo-ecological situation in the urbanized territories of Eastern Finland level of implementation of results: the analysis of environmental and geochemical situation in the urbanized territories of Finland is part of an integrated ecological-geochemical monitoring of the territories held by the Department GEGH TPU. Analytical material will be used in the educational process. Application field: the results of ecological-geochemical monitoring in the urbanized territories of Finland can be used by conservation organizations for estimates on the content of chemical elements in the soils and the living facilities of urban agglomerations

    GaAs detectors and electronics

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