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Hélia Harumi Sato - One of the best experts on this subject based on the ideXlab platform.
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Immobilization of Serratia plymuthica by ionic gelation and cross-linking with transglutaminase for the conversion of sucrose into Isomaltulose
Bioprocess and Biosystems Engineering, 2021Co-Authors: Priscila Hoffmann Carvalho, Haroldo Yukio Kawaguti, Weysser Felipe Cândido Souza, Hélia Harumi SatoAbstract:Isomaltulose is an alternative sugar obtained from sucrose using some bacteria producing glycosyltransferase. This work aimed to optimize conditions for the immobilization of Serratia plymuthica through ionic gelation and cross-linking by transglutaminase using the sequential experimental strategy for the conversion of sucrose into Isomaltulose. The effect of five variables (concentrations of cell mass, alginate, gelatin, transglutaminase, and calcium chloride) was studied, as well as the interactions between them on the matrix composition for the S. plymuthica immobilization. Three experimental designs were used to optimize the concentrations of each variable to obtain higher concentration of Isomaltulose. A high conversion of sucrose into Isomaltulose (71.04%) was obtained by the cells immobilized in a matrix composed of alginate (1.7%), CaCl_2 (0.25 mol/L), gelatin (0.5%), transglutaminase (3.5%) and cell mass (33.5%). As a result, the transglutaminase application as a cross-linking agent improved the immobilization of Serratia plymuthica cells and the conversion of sucrose into Isomaltulose.
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Electronic Journal of Biotechnology
2016Co-Authors: Católica Valparaíso, Haroldo Yukio Kawaguti, Eiric Manrich, Yukio Kawaguti, Haroldo Manrich, Eiric Harumi Sato, Biocen Do Brasil, Rua Pedro Stancato, Hélia Harumi SatoAbstract:Application of response surface methodology for glucosyltransferase production and conversion of sucrose into Isomaltulose using free Erwinia sp. cell
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DOI: 10.2225/vol9-issue5-fulltext-6 RESEARCH ARTICLE
2016Co-Authors: Haroldo Yukio Kawaguti, Eiric Manrich, Biocen Do Brasil, Rua Pedro Stancato, Hélia Harumi SatoAbstract:Application of response surface methodology for glucosyltransferase production and conversion of sucrose into Isomaltulose using free Erwinia sp. cell
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Isomaltulose production using free and immobilized Serratia plymuthica cells
African Journal of Biotechnology, 2016Co-Authors: Daniela Castilho Orsi, Hélia Harumi SatoAbstract:Isomaltulose is a low cariogenic sweetener used as a substitute for sucrose in the food industry. In this study, Isomaltulose production by Serratia plymuthica ATCC 15928 was performed using free and immobilized cells. Response Surface Methodology was employed to evaluate the influence of temperature, wet cell mass concentration and sucrose concentration during the conversion of sucrose into Isomaltulose by free cells. After 2 h of reaction time in shake flasks, a high production of Isomaltulose (85.23%) was obtained with a temperature of 25oC, wet cell mass of 20% (w/v) and sucrose solution of 25% (w/v). The free cells were reused during seven successive batches and resulted in efficient Isomaltulose conversion between 83.74 and 67.37%. The production of Isomaltulose by immobilized cells in calcium alginate was studied in a packed bed bioreactor during seven days in a continuous process. A conversion yield of sucrose into Isomaltulose between 81.26 and 70.89% was obtained, using immobilized cells in calcium alginate SynthO 2% (w/v), sucrose solution of 35% (w/v), wet cell mass of 30% (w/v) and temperature of 25oC. The conversion of sucrose into Isomaltulose remained high using free cells and using immobilized cells in calcium alginate during the period of execution of the experiments. Key words: Isomaltulose, glucosyltransferase, free cells, immobilized cells, Serratia plymuthica.
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Immobilization of Erwinia sp. D12 Cells in Alginate-Gelatin Matrix and Conversion of Sucrose into Isomaltulose Using Response Surface Methodology.
Enzyme research, 2011Co-Authors: Haroldo Yukio Kawaguti, Priscila Hoffmann Carvalho, Joelise De Alencar Figueira, Hélia Harumi SatoAbstract:Isomaltulose is a noncariogenic reducing disaccharide and also a structural isomer of sucrose and is used by the food industry as a sucrose replacement. It is obtained through enzymatic conversion of microbial sucrose isomerase. An Erwinia sp. D12 strain is capable of converting sucrose into Isomaltulose. The experimental design technique was used to study the influence of immobilization parameters on converting sucrose into Isomaltulose in a batch process using shaken Erlenmeyer flasks. We assessed the effect of gelatin and transglutaminase addition on increasing the reticulation of granules of Erwinia sp. D12 cells immobilized in alginate. Independent parameters, sodium alginate concentration, cell mass concentration, CaCl2 concentration, gelatin concentration, and transglutaminase concentration had all a significant effect (Pl0.05) on Isomaltulose production. Erwinia sp. D12 cells immobilized in 3.0% (w/v) sodium alginate, 47.0% (w/v) cell mass, 0.3 molL-1 CaCl2, 1.7% (w/v) gelatin and 0.15% (w/v) transglutaminase presented sucrose conversion into Isomaltulose, of around 50–60% in seven consecutive batches.
Haroldo Yukio Kawaguti - One of the best experts on this subject based on the ideXlab platform.
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Immobilization of Serratia plymuthica by ionic gelation and cross-linking with transglutaminase for the conversion of sucrose into Isomaltulose
Bioprocess and Biosystems Engineering, 2021Co-Authors: Priscila Hoffmann Carvalho, Haroldo Yukio Kawaguti, Weysser Felipe Cândido Souza, Hélia Harumi SatoAbstract:Isomaltulose is an alternative sugar obtained from sucrose using some bacteria producing glycosyltransferase. This work aimed to optimize conditions for the immobilization of Serratia plymuthica through ionic gelation and cross-linking by transglutaminase using the sequential experimental strategy for the conversion of sucrose into Isomaltulose. The effect of five variables (concentrations of cell mass, alginate, gelatin, transglutaminase, and calcium chloride) was studied, as well as the interactions between them on the matrix composition for the S. plymuthica immobilization. Three experimental designs were used to optimize the concentrations of each variable to obtain higher concentration of Isomaltulose. A high conversion of sucrose into Isomaltulose (71.04%) was obtained by the cells immobilized in a matrix composed of alginate (1.7%), CaCl_2 (0.25 mol/L), gelatin (0.5%), transglutaminase (3.5%) and cell mass (33.5%). As a result, the transglutaminase application as a cross-linking agent improved the immobilization of Serratia plymuthica cells and the conversion of sucrose into Isomaltulose.
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Enzymatic conversion of sucrose into Isomaltulose.
2017Co-Authors: Haroldo Yukio KawagutiAbstract:Resumo: A Isomaltulose é um dissacarídeo redutor, isômero da sacarose, que possui um sabor adocicado suave e propriedades físicas e sensoriais muito similares, que tem sido considerado um substituto promissor da sacarose na indústria de alimentos, devido a algumas características como baixo potencial cariogênico e baixo índice glicêmico, promoção do crescimento de bifidobactérias benéficas da microbiota intestinal, e por apresentar maior estabilidade em relação à sacarose em alimentos e bebidas acidificados, além de poder ser convertido para isomalte, um açúcar álcool dietético e não cariogênico aplicado na indústria de alimentos e farmacêutica. Os objetivos deste trabalho foram otimizar um meio de cultivo, de menor custo, para a produção da enzima glicosiltransferase pela linhagem Erwinia sp. D12 e estudar a produção de Isomaltulose a partir de sacarose utilizando-se células livres e células imobilizadas em alginato de cálcio. Na otimização do meio de cultivo, em frascos sob agitação, a máxima atividade obtida foi de 12,4 UA de glicosiltransferase/mL de meio de cultivo após 8 horas de fermentação a 30ºC, em meio composto de 150 g/L de melaço de cana-de-açúcar, 20 g/L de água de maceração de milho- Milhocina®, 15 g/L de extrato de levedura Prodex Lac SDÒ, e pH ajustado a 7,5. No estudo da produção de glicosiltransferase, em fermentador de 6,6 litros, utilizando-se o meio de cultivo otimizado foi obtida máxima atividade de 22,5 UA de glicosiltransferase/mL de meio de cultivo, após 8 horas de fermentação a 27oC. No estudo da produção de Isomaltulose por células íntegras imobilizadas de Erwinia sp. D12 em alginato de cálcio foi verificado que o tratamento dos grânulos de células imobilizadas com 0,06% de glutaraldeído, promoveu uma maior taxa de conversão, sendo obtido cerca de 72,3% de Isomaltulose, após 12 horas de incubação em frascos sob agitação a 30ºC. As células íntegras imobilizadas e tratadas com 0,06% de glutaraldeído, em colunas de leito empacotado, apresentaram maior estabilidade do que àquelas imobilizadas sem tratamento com o aditivo, e mantiveram a conversão de sacarose em Isomaltulose entre 50-60% por 10 dias, a partir de solução de sacarose 35% e fluxo de 0,56 mL/min a 30ºC. Foram estudados diferentes tratamentos para a preparação de células íntegras, células lisadas e extrato enzimático bruto imobilizados em alginato de cálcio. Os métodos que mostraram melhores resultados, em processo em batelada, foi o extrato enzimático bruto imobilizado em alginato de cálcio (EEI), em que foram obtidas taxas de conversão entre 59,7% e 63,3%; e células lisadas por sonicação e imobilizadas (CSI), com taxas de conversão entre 47,6% e 62,3%. A coluna de leito empacotado contendo grânulos de células lisadas imobilizadas (CSI) apresentou maior estabilidade do que a coluna contendo os grânulos de extrato enzimático bruto imobilizado (EEI). A coluna de leito empacotado de CSI converteu 53-59% de sacarose em Isomaltulose durante sete dias, posteriormente houve queda lenta e gradual da conversão não havendo mais transformação em Isomaltulose após 21 dias. No estudo da produção de Isomaltulose utilizando-se células livres de Erwinia sp. D12, em processo em batelada, foi verificado o efeito do pH, da temperatura, da concentração do substrato sacarose e da concentração de massa celular em frascos agitados a 150 rpm e 30ºC. A conversão de sacarose em Isomaltulose foi favorecida utilizando-se temperaturas superiores a 30ºC, pH entre 6,0-6,5, massa celular entre 7,5- 12,5% e solução de sacarose de 20-35%, obtendo-se rendimentos de Isomaltulose acima de 50%. No estudo da vida útil das células livres em escala de bancada, utilizando-se frascos Erlenmeyers sob agitação, foi verificado que os parâmetros de conversão fixados a: temperatura de 35ºC, pH 6,5, concentração de substrato sacarose 35% e concentração de massa celular 10% foram os mais favoráveis, promovendo um alto rendimento em Isomaltulose entre 70-75%, por 16 bateladas. Os ensaios realizados em escala piloto demonstraram a viabilidade da conversão de sacarose em Isomaltulose por células livres, em que foram obtidos cerca de 114 litros de xarope com alto teor de Isomaltulose (63,40%). Os cristais de Isomaltulose, após clarificação e purificação do xarope convertido, apresentaram pureza de 96,5%.Abstract:Isomaltulose is a reducing disaccharide and a structural isomer of sucrose. It has a mild sweet flavour and very similar physical and sensorial properties and has been considered as a promising substitute for sucrose in the food industry, due to some of its characteristics such as a low cariogenic potential and low glycemic index and the promotion of beneficial bifid bacteria in the intestinal microbial flora. It also shows greater stability than sucrose in acidified foods and drinks, and can be converted into isomalt, a dietetic sugar alcohol with no cariogenic potential for use in the food and pharmaceutical industries. The objectives of this research were the optimisation of a culture medium with reduced costs for the production of the enzyme glucosyltransferase by the strain Erwinia sp. D12, and the study of Isomaltulose production from sucrose by free and immobilized cells. In the optimisation of the culture medium in shaken flasks, the highest glucosyltransferase activity achieved was 12.4 UA/mL of culture medium after 8 hours of fermentation at 30ºC, in a medium composed of 150 g/L of sugar cane molasses, 20 g/L of corn steep liquor- Milhocina® and 15 g/L of yeast extract Prodex Lac SD®, with the pH adjusted to 7.5. In the study for glucosyltransferase production in a 6.6-liter reactor using the optimised culture medium, the highest glucosyltransferase production achieved was 22.5 UA/mL of culture medium, after 8 hours of fermentation at 27ºC. In the study for Isomaltulose production using Erwinia sp. D12 cells immobilized in calcium alginate, it was shown that the addition of 0.06% glutaraldehyde during the immobilization process, promoted a higher conversion rate, reaching about 72.3% Isomaltulose after 12 hours of incubation at 30°C in shaken flasks. The immobilized whole cells treated with 0.06% glutaraldehyde, used in packed-bed reactors, presented greater stability than those immobilized without the addition of the additive, and maintained the conversion of sucrose into Isomaltulose between 50-60% for 10 days, using a 35% sucrose solution with a flow rate of 0.56 mL/min at 30ºC. Different treatments were studied for the preparation of whole cells, lysed cells and a crude enzyme extract immobilized in calcium alginate. The methods that showed the best results in batch processes were the crude enzyme extract immobilized in calcium alginate (EEI), where conversion rates between 59.7% and 63.3% were achieved; and immobilized lysed cells (CSI), with conversion rates between 47.6% and 62.3%. The packed bed column containing granules of immobilized lysed cells (CSI) presented greater stability than that containing granules of immobilized crude enzymatic extract (EEI). The packed bed column with CSI converted 53-59% of sucrose into Isomaltulose during seven days, and then showed a gradual decline in conversion, ceasing completely after 21 days. In the study of Isomaltulose production using free Erwinia sp. D12 cells in a batch process, the effects of pH, temperature, sucrose substrate concentration and cell mass concentration were determined in shaken flasks at 150 rpm and 30ºC. The following conditions favoured the conversion of sucrose into Isomaltulose: temperatures above 30ºC, pH between 6.0-6.5, cell mass between 7.5-12.5% and a sucrose concentration between 20-35%; when Isomaltulose yields above 50% were obtained. The half-life of the free cells was studied on a bench scale in shaken Erlenmeyers flasks and it was shown that the following fixed conversion parameters were the most favourable: temperature of 35ºC, pH 6.5, 35% sucrose substrate concentration and 10% cell mass concentration; promoting high Isomaltulose yields between 70-75%, for 16 batches. The pilot scale assays demonstrated the viability of the conversion of sucrose into Isomaltulose by free cells, obtaining about 114 liters of high Isomaltulose syrup (63.40%). The Isomaltulose crystals, after clarification and purification of the converted syrup, showed a purity of 96.5%
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Electronic Journal of Biotechnology
2016Co-Authors: Católica Valparaíso, Haroldo Yukio Kawaguti, Eiric Manrich, Yukio Kawaguti, Haroldo Manrich, Eiric Harumi Sato, Biocen Do Brasil, Rua Pedro Stancato, Hélia Harumi SatoAbstract:Application of response surface methodology for glucosyltransferase production and conversion of sucrose into Isomaltulose using free Erwinia sp. cell
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DOI: 10.2225/vol9-issue5-fulltext-6 RESEARCH ARTICLE
2016Co-Authors: Haroldo Yukio Kawaguti, Eiric Manrich, Biocen Do Brasil, Rua Pedro Stancato, Hélia Harumi SatoAbstract:Application of response surface methodology for glucosyltransferase production and conversion of sucrose into Isomaltulose using free Erwinia sp. cell
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Immobilization of Erwinia sp. D12 Cells in Alginate-Gelatin Matrix and Conversion of Sucrose into Isomaltulose Using Response Surface Methodology.
Enzyme research, 2011Co-Authors: Haroldo Yukio Kawaguti, Priscila Hoffmann Carvalho, Joelise De Alencar Figueira, Hélia Harumi SatoAbstract:Isomaltulose is a noncariogenic reducing disaccharide and also a structural isomer of sucrose and is used by the food industry as a sucrose replacement. It is obtained through enzymatic conversion of microbial sucrose isomerase. An Erwinia sp. D12 strain is capable of converting sucrose into Isomaltulose. The experimental design technique was used to study the influence of immobilization parameters on converting sucrose into Isomaltulose in a batch process using shaken Erlenmeyer flasks. We assessed the effect of gelatin and transglutaminase addition on increasing the reticulation of granules of Erwinia sp. D12 cells immobilized in alginate. Independent parameters, sodium alginate concentration, cell mass concentration, CaCl2 concentration, gelatin concentration, and transglutaminase concentration had all a significant effect (Pl0.05) on Isomaltulose production. Erwinia sp. D12 cells immobilized in 3.0% (w/v) sodium alginate, 47.0% (w/v) cell mass, 0.3 molL-1 CaCl2, 1.7% (w/v) gelatin and 0.15% (w/v) transglutaminase presented sucrose conversion into Isomaltulose, of around 50–60% in seven consecutive batches.
Daohai Zhang - One of the best experts on this subject based on the ideXlab platform.
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substrate induction of Isomaltulose synthase in a newly isolated klebsiella sp lx3
Journal of Applied Microbiology, 2003Co-Authors: Chunjian Zhao, Daohai ZhangAbstract:Aims: Production of Isomaltulose by newly isolated Klebsiella sp. LX3. Methods and Results: The bacterial isolate LX3, which transforms sucrose to Isomaltulose and trehalulose, has been isolated from a soil sample in Singapore. Morphological and biochemical analysis, as well as 16s rRNA sequence demonstrated that the isolate could represent a new member of genus Klebsiella. The strain has several interesting features. The immobilized cells of Klebsiella sp. LX3 convert more than 99% of sucrose to products that consist of more than 87% of Isomaltulose, 11·6% of trehalulose, and <1% of glucose. Conclusions: The production of Isomaltulose synthase in isolate LX3 is inducible by its substrate sucrose and the sugars containing a fructofuranosyl group. Significance and Impact of Study: It would be useful for future biotechnological applications to understand the structural features or motifs of the Isomaltulose synthases that determine the sucrose conversion efficiency and the ratio of the conversion products.
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A motif rich in charged residues determines product specificity in Isomaltulose synthase.
FEBS letters, 2003Co-Authors: Daohai Zhang, Kunchithapadam Swaminathan, Lian Hui ZhangAbstract:Isomaltulose synthase (PalI) catalyzes hydrolysis of sucrose and formation of alpha-1,6 and alpha-1,1 bonds to produce Isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofranose) and small amount of trehalulose (alpha-D-glucosylpyranosyl-1,1-D-fructofranose). A potential Isomaltulose synthase-specific motif ((325)RLDRD(329)), that contains a 'DxD' motif conserved in many glycosyltransferases, was identified based on sequence comparison with reference to the secondary structural features of PalI and homologs. Site-directed mutagenesis analysis of the motif showed that the four charged amino acid residues (Arg(325), Arg(328), Asp(327) and Asp(329)) influence the enzyme kinetics and determine the product specificity. Mutation of these four residues increased trehalulose formation by 17-61% and decreased Isomaltulose by 26-67%. We conclude that the 'RLDRD' motif controls the product specificity of PalI.
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Substrate induction of Isomaltulose synthase in a newly isolated Klebsiella sp. LX3
Journal of applied microbiology, 2003Co-Authors: Chunjian Zhao, Daohai ZhangAbstract:Aims: Production of Isomaltulose by newly isolated Klebsiella sp. LX3. Methods and Results: The bacterial isolate LX3, which transforms sucrose to Isomaltulose and trehalulose, has been isolated from a soil sample in Singapore. Morphological and biochemical analysis, as well as 16s rRNA sequence demonstrated that the isolate could represent a new member of genus Klebsiella. The strain has several interesting features. The immobilized cells of Klebsiella sp. LX3 convert more than 99% of sucrose to products that consist of more than 87% of Isomaltulose, 11·6% of trehalulose, and
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Expression, crystallization and preliminary X-ray analysis of Isomaltulose synthase (PalI) from Klebsiella sp. LX3.
Acta Crystallographica Section D Biological Crystallography, 2002Co-Authors: Daohai Zhang, Lian Hui Zhang, Kunchithapadam SwaminathanAbstract:Isomaltulose synthase (PalI) catalyzes the hydrolysis of the alpha-1,2 bond between the glucose and fructose moieties of sucrose and the formation of alpha-1,6 and alpha-1,1 bonds between the two components to produce Isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-D-fructofranose), respectively. The PalI protein has been overexpressed, purified and crystallized at 295 K using the hanging-drop vapour-diffusion method. The crystals diffract to 2.2 A resolution using synchrotron radiation and belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 59.239, b = 94.153, c = 111.294 A.
Priscila Hoffmann Carvalho - One of the best experts on this subject based on the ideXlab platform.
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Immobilization of Serratia plymuthica by ionic gelation and cross-linking with transglutaminase for the conversion of sucrose into Isomaltulose
Bioprocess and Biosystems Engineering, 2021Co-Authors: Priscila Hoffmann Carvalho, Haroldo Yukio Kawaguti, Weysser Felipe Cândido Souza, Hélia Harumi SatoAbstract:Isomaltulose is an alternative sugar obtained from sucrose using some bacteria producing glycosyltransferase. This work aimed to optimize conditions for the immobilization of Serratia plymuthica through ionic gelation and cross-linking by transglutaminase using the sequential experimental strategy for the conversion of sucrose into Isomaltulose. The effect of five variables (concentrations of cell mass, alginate, gelatin, transglutaminase, and calcium chloride) was studied, as well as the interactions between them on the matrix composition for the S. plymuthica immobilization. Three experimental designs were used to optimize the concentrations of each variable to obtain higher concentration of Isomaltulose. A high conversion of sucrose into Isomaltulose (71.04%) was obtained by the cells immobilized in a matrix composed of alginate (1.7%), CaCl_2 (0.25 mol/L), gelatin (0.5%), transglutaminase (3.5%) and cell mass (33.5%). As a result, the transglutaminase application as a cross-linking agent improved the immobilization of Serratia plymuthica cells and the conversion of sucrose into Isomaltulose.
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Conversion of Isomaltulose and trehalulose from sucrose by Serratia plymuthicacells free and immobilised using transglutaminase
2017Co-Authors: Priscila Hoffmann CarvalhoAbstract:Resumo: A Isomaltulose e a trealulose são dissacarídeos isômeros estruturais, que podem ser obtidos a partir da sacarose utilizando-se glicosiltransferase bacteriana. Esses dissacarídeos são considerados açúcares alternativos de grande potencial para uso nas indústrias de alimentos e farmacêutica porque são hidrolisados e absorvidos mais lentamente e apresentam baixo potencial cariogênico comparado com a sacarose. Foi estudada a imobilização de células de Serratia plymuthica ATCC 15928, produtora de glicosiltransferase por gelificação iônica em gel alginato contendo transglutaminase (TG) e também a utilização de células livres para a conversão de sacarose em Isomaltulose e trealulose. Utilizando-se células livres de Serratia plymuthica ATCC 15928 foi obtido 70% de conversão em Isomaltulose e 8% de trealulose a 25°C por 10 bateladas de 15 minutos, a partir de solução de sacarose 30%. Entre as cinco amostras de alginato de sódio testadas, para a imobilização das células de S. plymuthica ATCC 15928 com e sem adição de TG, foram obtidos melhores resultados (médio de três bateladas) de conversão de sacarose (37,4% de Isomaltulose) utilizando o alginato de sódio B, de alta viscosidade (14.000cP Sigma ¿ A 7128) em presença de TG. Nas condições estudadas (1,7% de alginato de sódio, 30% de massa celular úmida, solução de cloreto de sódio 0,2Mol/L, 2% de TG e 35% de sacarose) também houve maior facilidade de formação de grânulos uniformes. A presença de TG como agente de reticulação na matriz de imobilização melhorou a estabilidade de conversão por três bateladas onde observou-se resultado médio 27% maior com relação a matriz com o mesmo tipo de alginato (B) em ausência de TG. A composição da matriz de imobilização com adição de TG foi otimizada por metodologia de planejamento experimental, assim como a adição de gelatina como fonte de proteína adicional para promoção de ligações cruzadas catalisadas pela TG. Os melhores resultados de conversão de sacarose (solução 35%) em Isomaltulose (72,66% de Isomaltulose e 8% de trealulose em 4 bateladas de 24horas) foram obtidos utilizando-se matriz de polissacarídeo-proteína composto de 1,7% de alginato de sódio 14.000cP (Sigma®-A7128), 0,25mol/L de CaCl2, 0,5% de gelatina, 3,5% de TG e concentração de massa celular úmida superior a 35% (m:v). Verificou-se que a adição de ALMP na matriz de alginato de cálcio-gelatina-TG para imobilização de S. plymuthica, testada por planejamentos experimentais seqüenciais, não aumentou a estabilidade da taxa de conversão de sacarose em Isomaltulose quando comparada com as células imobilizadas em matriz de alginato de cálcio-gelatina-TG. Em processo contínuo utilizando-se coluna empacotada com células de S. plymuthica imobilizadas em matriz otimizada e descrita acima, foi obtida taxa de conversão média de 64% de sacarose em Isomaltulose durante 200 horas de processo, equivalente a 0,27g de Isomaltulose/g de células imobilizadas/hora em coluna a 25°C e fluxo de substrato (35% de sacarose) 0,2mL/minAbstract:The Isomaltulose and trehalulose are disaccharides and structural isomers, which can be obtained from sucrose using bacterial glycosyltransferase. These disaccharide are considered alternative sugars with great potential for use in the food and pharmaceutical industries because they are hydrolyzed and absorbed more slowly and have a low cariogenic potential compared with sucrose. The conversion of sucrose to Isomaltulose and trehalulose was estudied using immobilized and free cells of Serratia plymuthica ATCC 15928. The cells were immobilized by ionic gelation in alginate gel containing transglutaminase. Using free cells of Serratia plymuthica ATCC 15928 was obtained 70% Isomaltulose conversion and 8% trehalulose conversion at 25° C in 10 batches of 15 minutes from a 30% sucrose solution. Among the five samples of sodium alginate tested for S. plymuthica ATCC 15928 cells immobilization, with or without the addition of TG, the best results (average of three batches) were obtained using sodium alginate B, high viscosity (14.000cP Sigma - A 7128) in the presence of TG, leading to 37.4% Isomaltulose conversion from sucrose. In the studied conditions (1.7% sodium alginate, 30% wet cell mass solution of sodium chloride 0.2 Mol/L, 2% TG, 35% sucrose) was also easier to form uniform granules. The presence of TG as a crosslinking agent in the immobilization matrix improved the stability during three batches, resulting in an 27% higher average conversion with respect to a same type of alginate (B) matrix in absence of TG. Immobilization matrix compositions with addition of TG was optimized by experimental design methodology, as well as the addition of gelatin as a protein source for promoting additional crosslinking catalyzed by TG. The best results conversion of sucrose (35% solution) into Isomaltulose (72.66% of Isomaltulose and 8% of trehalulose in 4 batches of 24 hours) were obtained using proteinpolysaccharide matrix composed of 1.7% alginate 14.000cP sodium (Sigma® A7128), 0.25 Mol/L CaCl2, 0.5% gelatin, 3.5% TG, and wet cell mass concentration of 35% (w:v). It has been found that the addition of ALMP (amidated low methoxyl pectin) into the calcium alginate-gelatin-TG matrix for immobilization of S. plymuthica, tested by sequential experimental design, do not increase the stability of sucrose to Isomaltulose conversions rate when compared with cells immobilized in calcium alginate -gelatin-TG matrix. In continuous process using a packed column with S. plymuthica cell's immobilized in the optimized matrix described above, it was obtained an average conversion rate of 64% sucrose to Isomaltulose during a 200 hours process, equivalent to 0.27g Isomaltulose per gram of immobilized cell per hour, in a column at 25° C and using flow substrate (35% sucrose) of 0.2 mL / mi
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Immobilization of Erwinia sp. D12 Cells in Alginate-Gelatin Matrix and Conversion of Sucrose into Isomaltulose Using Response Surface Methodology.
Enzyme research, 2011Co-Authors: Haroldo Yukio Kawaguti, Priscila Hoffmann Carvalho, Joelise De Alencar Figueira, Hélia Harumi SatoAbstract:Isomaltulose is a noncariogenic reducing disaccharide and also a structural isomer of sucrose and is used by the food industry as a sucrose replacement. It is obtained through enzymatic conversion of microbial sucrose isomerase. An Erwinia sp. D12 strain is capable of converting sucrose into Isomaltulose. The experimental design technique was used to study the influence of immobilization parameters on converting sucrose into Isomaltulose in a batch process using shaken Erlenmeyer flasks. We assessed the effect of gelatin and transglutaminase addition on increasing the reticulation of granules of Erwinia sp. D12 cells immobilized in alginate. Independent parameters, sodium alginate concentration, cell mass concentration, CaCl2 concentration, gelatin concentration, and transglutaminase concentration had all a significant effect (Pl0.05) on Isomaltulose production. Erwinia sp. D12 cells immobilized in 3.0% (w/v) sodium alginate, 47.0% (w/v) cell mass, 0.3 molL-1 CaCl2, 1.7% (w/v) gelatin and 0.15% (w/v) transglutaminase presented sucrose conversion into Isomaltulose, of around 50–60% in seven consecutive batches.
Chao Liu - One of the best experts on this subject based on the ideXlab platform.
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bioinspired production of antibacterial sucrose isomerase sponge for the synthesis of Isomaltulose
Advanced Synthesis & Catalysis, 2016Co-Authors: Juanjuan Qiu, Xiaoliu Liu, Chao LiuAbstract:Isomaltulose is a new functional sweetener that possesses biological characteristics and can be obtained by enzymatic synthesis using sucrose as substrate. In this study, the sucrose isomerase (SIase) was successfully immobilized on the sponge synthesized with ϵ-poly-l-lysine and gelatin. The inhibition zones proved that the sponge possessed a significant bacteriostatic function, which can effectively prevent the collapse of the scaffolds of the immobilized enzymes. The immobilized SIase activity reached up to 71.58 U g−1 (the SIase loading was about 153.43 mg g−1), and the activity recovery was approximately 84.50%. After immobilization, the optimum pH of SIase decreased from 6.0 to 5.5 and the optimum temperature increased from 30 °C to 40 °C. The affinity of SIase to substrate was basically unchanged. Immobilized SIase still exhibited more than 90% sucrose conversion after 13 consecutive cycles, which indicated that it had a good operational stability. Furthermore, the immobilized SIase has the potential for Isomaltulose production, with 200 g L−1 sucrose solution as its substrate in the food industry. Isomaltulose was isolated in 83.58% yield and high purity (97.3%).
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Bioinspired Production of Antibacterial Sucrose Isomerase‐Sponge for the Synthesis of Isomaltulose
Advanced Synthesis & Catalysis, 2016Co-Authors: Juanjuan Qiu, Xiaoliu Liu, Chao LiuAbstract:Isomaltulose is a new functional sweetener that possesses biological characteristics and can be obtained by enzymatic synthesis using sucrose as substrate. In this study, the sucrose isomerase (SIase) was successfully immobilized on the sponge synthesized with ϵ-poly-l-lysine and gelatin. The inhibition zones proved that the sponge possessed a significant bacteriostatic function, which can effectively prevent the collapse of the scaffolds of the immobilized enzymes. The immobilized SIase activity reached up to 71.58 U g−1 (the SIase loading was about 153.43 mg g−1), and the activity recovery was approximately 84.50%. After immobilization, the optimum pH of SIase decreased from 6.0 to 5.5 and the optimum temperature increased from 30 °C to 40 °C. The affinity of SIase to substrate was basically unchanged. Immobilized SIase still exhibited more than 90% sucrose conversion after 13 consecutive cycles, which indicated that it had a good operational stability. Furthermore, the immobilized SIase has the potential for Isomaltulose production, with 200 g L−1 sucrose solution as its substrate in the food industry. Isomaltulose was isolated in 83.58% yield and high purity (97.3%).
