74 research outputs found

    Biocatalysis: facts and trends

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    Brazil is renowned for its biodiversity; however, its economy is based on exotic plants, extraction and unsustainable use of natural resources. This issue was addressed in a recent QN review entitled Chemistry without Borders. In order to explore the potential of Brazilian biodiversity fully, sustainable development is required in key technological areas, such as biotechnology. This research field is consistent with the green chemistry and white technology principles. Therefore, biotechnology is a sustainable alternative to conventional technologies and is expected to account for 20% of global chemicals by 2020. Brazil is the second largest grower of biotech crops and biodiesel, but its main activities rely on the fermentative process. In order to stimulate the national biotechnology development, the Brazilian Federal Government launched a national policy for biotechnology in 2007 and the National Committee of Biotechnology was created. Among the outstanding biotechnological processes, biocatalysis is one of the most important alternatives to conventional processing, and this field has changed dramatically with the advent of recombinant DNA technology in the 1970s, when large quantities of enzymes were accessible. The direct evolution methodology in the 1990s was a breakthrough and allowed tailoring of enzymes possessing high stability and stereoselectivity. However, about 60 years after the first industrial enzymatic biotransformation of steroids, the full potential of biocatalysis is far from being achieved. Future challenges in this field concern the multienzyme cascade reactions associated with optimized chemoenzymatic processes, and some recent industrial application of biocatalysts are also highlighted in this perspective.15871590Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Controlling factors determining the selective HSCN addition to double bonds and their application to the synthesis of 7-isothiocyano-7,8-alpha-dihydro-bisabolene

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    The reactivity of terminal and trisubstituted double bonds of monoterpenes with HSCN has been examined by GC giving evidence that kinetics is responsible for the chemoselective addition to terminal double bonds in terpenes. The results show that the addition to the terminal double bond is about 17 times faster than for trisubstituted double bonds and that the presence of the first SCN group in the molecule prevents a second addition. The presence of a hydroxyl or methoxy group in the molecule, decreases the reaction kinetics. Based on these kinetic experiments a two steps synthesis of the natural product 7-isothiocyano-7,8-dihydro-alpha-bisabolene using bisabolol as starting material, was planned and successfully accomplished.A reatividade de duplas ligações terminal e trissubstituída de monoterpenos com HSCN foi examinada por CG evidenciando que fatores cinéticos são responsáveis pela adição quimiosseletiva em duplas ligações terminais em terpenos. O resultado mostra que a adição é cerca de 17 vezes mais rápida em duplas terminais do que em duplas trissubstituídas e que a presença do primeiro grupo SCN impede a entrada de um segundo grupo. A presença de um grupo hidroxila ou metoxila na molécula diminui sensivelmente a velocidade da reação. A partir do estudo acima foi possível elaborar e realizar a síntese do produto natural 7-isothiocyano-7,8-dihydro-alfa-bisabolene em duas etapas a partir do bisabolol.661666Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Esterase screening using whole cells of Brazilian soil microorganisms

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    A miniaturized enzymatic assay using fluorescent probes to reveal esterase producing microorganisms was optimized and applied to screen 64 soil bacterial strains. The best results were validated using traditional non-fluorogenic assays with acetyl and propanoyl phenylethanol to confirm the miniaturized results. The most active microorganisms belong to the genus Bacillus showing esterase activity and good enantiomeric ratios for the resolution of phenylethanol derivatives (E > 30). Part of the microorganisms are kept in our laboratory in glycerol or freeze-dried and the best microorganisms will be deposited in the CBMAI/CPQBA/Unicamp culture collection.Um ensaio enzimático miniaturizado com sondas fluorescentes para triagem rápida de microrganismos produtores de esterases foi implementado e aplicado a 64 linhagens de bactérias de solo. Os melhores resultados foram validados por métodos convencionais e substratos não fluorogênicos (feniletanol acetilado e propanoilado) e confirmaram os resultados obtidos nas triagens rápidas. Os microrganismos que apresentaram atividades enzimáticas mais relevantes (razão enantiomérica E > 30) na hidrólise de ésteres e na obtenção de boas razões enantioméricas foram identificados como pertencentes ao gênero Bacillus. Parte dos microrganismos se encontra preservada em glicerol e/ou liofilizada no IQ/Unicamp e três linhagens serão depositadas na CBMAI do CPQBA/Unicamp como depósitos abertos.14841489Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Esterase screening using whole cells of Brazilian soil microorganisms

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    A miniaturized enzymatic assay using fluorescent probes to reveal esterase producing microorganisms was optimized and applied to screen 64 soil bacterial strains. The best results were validated using traditional non-fluorogenic assays with acetyl and propanoyl phenylethanol to confirm the miniaturized results. The most active microorganisms belong to the genus Bacillus showing esterase activity and good enantiomeric ratios for the resolution of phenylethanol derivatives (E > 30). Part of the microorganisms are kept in our laboratory in glycerol or freeze-dried and the best microorganisms will be deposited in the CBMAI/CPQBA/Unicamp culture collection

    Genome Sequence Of Bacillus Safensis Cfa06, Isolated From Biodegraded Petroleum In Brazil.

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    Bacillus safensis is a microorganism recognized for its biotechnological and industrial potential due to its interesting enzymatic portfolio. Here, as a means of gathering information about the importance of this species in oil biodegradation, we report a draft genome sequence of a strain isolated from petroleum.

    Binding Events of (S)-N-(3-Oxo-octanoyl)-homoserine Lactone with Agrobacterium tumefaciens Mutant Cells Studied by Saturation Transfer Difference NMR

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    Quorum-sensing is a widely studied communication phenomenon in bacteria, which involves the production and detection of signaling substances in relation with cell density and colony behavior. Herein, the membrane binding interactions of the signal (S)-N-(3-oxo-octanoyl)-HSL with A. tumefaciens NTL4(pZLR4) cells were studied using saturation transfer difference NMR spectroscopy (STD-NMR). The substance epitope map was obtained showing that the hydrophobic acyl chain is the most important interacting site for the signal and the cell membrane. Results were interpreted upon comparisons with a simpler system, using liposomes as membrane models. Some insights on the use of β-cyclodextrin as acyl-HSL carrier were also provided

    Enzymatic synthesis of structured lipids from liquid and fully hydrogenated high oleic sunflower oil

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    sem informaçãoStructured lipids (SL) were synthesized via enzymatic (EI) and chemical interesterification of high oleic sunflower oil (SO) and fully hydrogenated high oleic SO with Lipozyme TL IM (Thermomyces lanuginose) for 3 h at 70°C, 300 rpm. Reaction showed change211702716sem informaçãosem informaçãosem informaçã
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