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Biomimetic synthesis of magnetic composite particles for laccase immobilization / Xiaobing Zheng in Industrial & engineering chemistry research, Vol. 51 N° 30 (Août 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10140–10146 Titre : Biomimetic synthesis of magnetic composite particles for laccase immobilization Type de document : texte imprimé Auteurs : Xiaobing Zheng, Auteur ; Qi Wang, Auteur ; Yanjun Jiang, Auteur Année de publication : 2012 Article en page(s) : pp. 10140–10146 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Biomimetic  Magnetic  composite Résumé : Magnetic silica composite particles were prepared by using the biosilicification reaction, in which Fe3O4 nanoparticles were entrapped in a silica matrix. The composite particles were functionalized with 3-aminopropyltriethoxysilane (APTES). These functionalized magnetic composite particles were used to immobilize a kind of valuable bulky industrial enzyme (laccase). The incorporation of magnetic nanoparticles greatly facilitates the manipulation of the immobilized biocatalyst, since it can be easily and quickly recovered from the reaction system by the simple application of an external magnetic field. The effects of immobilization conditions were optimized and the activity of the immobilized laccase was investigated. The results showed that the highest specific activity of immobilized laccase reached to 224 U and the activity recovery was 83.9%. Compared with free laccase, the thermal, pH, operational and storage stabilities of the immobilized laccase were improved significantly. The catalytic activity of the immobilized laccase was also demonstrated by the degradation of two phenolic substances (i.e., 2,4-dichlorophenol and 4-chlorophenol). It was found that the removal rates of 2,4-dichlorophenol and 4-chlorophenol were 80.9% and 64.2% in about 12 h, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000908 [article] Biomimetic synthesis of magnetic composite particles for laccase immobilization [texte imprimé] / Xiaobing Zheng, Auteur ; Qi Wang, Auteur ; Yanjun Jiang, Auteur . - 2012 . - pp. 10140–10146. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10140–10146 Mots-clés : Biomimetic  Magnetic  composite Résumé : Magnetic silica composite particles were prepared by using the biosilicification reaction, in which Fe3O4 nanoparticles were entrapped in a silica matrix. The composite particles were functionalized with 3-aminopropyltriethoxysilane (APTES). These functionalized magnetic composite particles were used to immobilize a kind of valuable bulky industrial enzyme (laccase). The incorporation of magnetic nanoparticles greatly facilitates the manipulation of the immobilized biocatalyst, since it can be easily and quickly recovered from the reaction system by the simple application of an external magnetic field. The effects of immobilization conditions were optimized and the activity of the immobilized laccase was investigated. The results showed that the highest specific activity of immobilized laccase reached to 224 U and the activity recovery was 83.9%. Compared with free laccase, the thermal, pH, operational and storage stabilities of the immobilized laccase were improved significantly. The catalytic activity of the immobilized laccase was also demonstrated by the degradation of two phenolic substances (i.e., 2,4-dichlorophenol and 4-chlorophenol). It was found that the removal rates of 2,4-dichlorophenol and 4-chlorophenol were 80.9% and 64.2% in about 12 h, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000908

Green and efficient conversion of CO2 to methanol by biomimetic coimmobilization of three dehydrogenases in protamine-templated titania / Qianyun Sun in Industrial & engineering chemistry research, Vol. 48 N° 9 (Mai 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4210–4215 Titre : Green and efficient conversion of CO2 to methanol by biomimetic coimmobilization of three dehydrogenases in protamine-templated titania Type de document : texte imprimé Auteurs : Qianyun Sun, Auteur ; Yanjun Jiang, Auteur ; Zhongyi Jiang, Auteur Année de publication : 2009 Article en page(s) : pp. 4210–4215 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Carbon  dioxide  Mutienzyme  system  Titania  particles  Biomimetic  mineralization  process Résumé : A green and efficient mutienzyme system was established, which efficiently converted carbon dioxide into methanol, by encapsulating three dehydrogenases within titania particles through a facile and mild biomimetic mineralization process. The enzyme-containing titania particles were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results indicated that the enzyme-containing titania particles were amorphous and consisted of interconnected nanospheres with sizes in the range of 400−600 nm. The three encapsulated dehydrogenases (formate dehydrogenase, formaldehyde dehydrogenase, alcohol dehydrogenase) sequentially converted carbon dioxide into HCOOH, CHOH, and CH3OH using NADH as a terminal electron donor for each dehydrogenase-catalyzed reduction. Compared to the open-style system which directly performed the bioconversion using free enzymes in aqueous solution, higher reaction yield in a wider pH and temperature range was obtained by the closed-style coimmobilization multienzyme system. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801931j [article] Green and efficient conversion of CO2 to methanol by biomimetic coimmobilization of three dehydrogenases in protamine-templated titania [texte imprimé] / Qianyun Sun, Auteur ; Yanjun Jiang, Auteur ; Zhongyi Jiang, Auteur . - 2009 . - pp. 4210–4215. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4210–4215 Mots-clés : Carbon  dioxide  Mutienzyme  system  Titania  particles  Biomimetic  mineralization  process Résumé : A green and efficient mutienzyme system was established, which efficiently converted carbon dioxide into methanol, by encapsulating three dehydrogenases within titania particles through a facile and mild biomimetic mineralization process. The enzyme-containing titania particles were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results indicated that the enzyme-containing titania particles were amorphous and consisted of interconnected nanospheres with sizes in the range of 400−600 nm. The three encapsulated dehydrogenases (formate dehydrogenase, formaldehyde dehydrogenase, alcohol dehydrogenase) sequentially converted carbon dioxide into HCOOH, CHOH, and CH3OH using NADH as a terminal electron donor for each dehydrogenase-catalyzed reduction. Compared to the open-style system which directly performed the bioconversion using free enzymes in aqueous solution, higher reaction yield in a wider pH and temperature range was obtained by the closed-style coimmobilization multienzyme system. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801931j

Novel in situ batch reactor with a facile catalyst separation device for biodiesel production / Yanjun Jiang in Industrial & engineering chemistry research, Vol. 51 N° 46 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 14935-14940 Titre : Novel in situ batch reactor with a facile catalyst separation device for biodiesel production Type de document : texte imprimé Auteurs : Yanjun Jiang, Auteur ; Hanqi Gu, Auteur ; Liya Zhou, Auteur Année de publication : 2013 Article en page(s) : pp. 14935-14940 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Production  Catalyst  Reactor  Batchwise  In  situ Résumé : In an effort to reduce the production cost of biodiesel and realize the lipase recovery of the in situ transesterification technology, a reactor with facile catalyst separation device was developed in this study. Compared with conventional method of biodiesel production, this improved reactive extraction technology can realize not only the biodiesel synthesis in a single step, but also the separation of immobilized lipases from the oilseed residues easily. This technology may present a sustainable, economically attractive process for biodiesel production. J. curcas L. seed, methanol, Lipozyme TL IM, and cosolvent n-hexane were used in this study. The effect of various process parameters on the yield of fatty acid methyl esters (FAMEs) was investigated. The highest FAMEs yield of 90.6% could be achieved under the optimum conditions: n-hexane/seed ratio of 3.5:1 mL/g, methanol/oil molar ratio of 6:1, 15% (w/w) of Lipozyme TL IM, reaction temperature of 45 °C, water content of 1.0%, and reaction time of 12 h. The lipase could maintain more than 40% of its initial activity after 13 batches operation under optimal reaction conditions. This simple in situ transesterification technology with facile catalyst separation device can be a potential route for biodiesel production, which may greatly reduce the processing steps and costs. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26679612 [article] Novel in situ batch reactor with a facile catalyst separation device for biodiesel production [texte imprimé] / Yanjun Jiang, Auteur ; Hanqi Gu, Auteur ; Liya Zhou, Auteur . - 2013 . - pp. 14935-14940. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 14935-14940 Mots-clés : Production  Catalyst  Reactor  Batchwise  In  situ Résumé : In an effort to reduce the production cost of biodiesel and realize the lipase recovery of the in situ transesterification technology, a reactor with facile catalyst separation device was developed in this study. Compared with conventional method of biodiesel production, this improved reactive extraction technology can realize not only the biodiesel synthesis in a single step, but also the separation of immobilized lipases from the oilseed residues easily. This technology may present a sustainable, economically attractive process for biodiesel production. J. curcas L. seed, methanol, Lipozyme TL IM, and cosolvent n-hexane were used in this study. The effect of various process parameters on the yield of fatty acid methyl esters (FAMEs) was investigated. The highest FAMEs yield of 90.6% could be achieved under the optimum conditions: n-hexane/seed ratio of 3.5:1 mL/g, methanol/oil molar ratio of 6:1, 15% (w/w) of Lipozyme TL IM, reaction temperature of 45 °C, water content of 1.0%, and reaction time of 12 h. The lipase could maintain more than 40% of its initial activity after 13 batches operation under optimal reaction conditions. This simple in situ transesterification technology with facile catalyst separation device can be a potential route for biodiesel production, which may greatly reduce the processing steps and costs. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26679612