Sintese de oligossacarideos em meio organico e aquoso utilizando-se inulinase livre e imobilizada produzida por Kluyveromces marxianus ATCC 16045 e NRRL Y-7571. / Sintese of oligossacarideos in half watery organico and using inulinase exempts and immobilized produced for Kluyveromces marxianus ATCC 16045 and NRRL Y-757.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2004

RESUMO

Functional foods, which are beneficial to human beings, have been attracting more and more interest in the last years. Many oligosaccharides, which are also called prebiotics, have been included in some food formulations, making them potentially more healthful. One of the most important effect is the improvement of the good intestinal flora, more significantly the number of the bifidobacteria. The objective of this work was to study the characterization by free and immobilized inulinase; and the optimization of the conversion of sucrose into fructooligosaccharides in organic and aqueous media, from Kluyveromyces marxianus ATCC 16045 and NRRL Y-7571 using immobilized and free enzyme. Synthesis was carried out in stirred reactors and the synthesis products were identified and measured by ions chromatography. Optimum reaction temperature to ATCC 16045 was 55°C for free and immobilized enzyme for independent of the used percentage of solvent. Better stability temperature was 50°C for free and immobilized with a half-life of about 12 and 38 hours for free and immobilized, respectively. Optimum pH reactions was 4.8 and 4.4 for free and immobilized enzyme, respectively, for independent of the used percentage of solvent. Better stability pH was 4.4, 4.8 and 4.4 for free enzyme with 25, 50 and 70% of solvent, respectively. To immobilized was 4.8. Kinetic study with the following kinetic constants: Km 0.016, 0.17 and 0.13 M and Vmax 10.6, 34.7 and 23.7 mol/(min.L) for free enzyme with 25, 50 and 70% of solvent, respectively. And to immobilized were Km 0.0035, 0.006 and 0.025 M and Vmax 39, 60 and 86 mol/(min.L) with 25, 50 and 70% of solvent, respectively. Optimum reaction temperature to NRRL Y-7571 was 50°C for free independent of the used percentage of solvent and was 55, 60 and 55°C for immobilized enzyme with 25, 50 and 70% of solvent, respectively. Better stability temperature was 50°C for free and immobilized with a half-life of about 15 and 19 hours for free and immobilized, respectively. Optimum pH reactions was 4.8 for free and immobilized enzyme, for the independent used percentage of solvent. Better stability pH was 4.4, 4.4 and 4.0 for free and 4.0, 4.0 and 4.4 for immobilized enzyme with 25, 50 and 70% of solvent, respectively. Kinetic study with the following kinetic constants: Km 0.026, 0.038 and 0.08 M and Vmax 11.3, 21.2 and 35.2 mol/(min.L) for free enzyme and to immobilized Km 0.006, 0.002 and 0.01 M and Vmax 22.9, 27 and 33.2 mol/(min.L) with 25, 50 and 70% of solvent, respectively. Factorial design and response surface techniques were used to optimize the synthesis of fructooligosaccharides. Six parameters were studied (pH, temperature, sucrose concentration, enzyme, organic: aqueous solvent ratio and polyethylene glycol [PEG] concentration) on the maximum conversion of sucrose into fructooligosaccharides and productivity. To ATCC 16045 the maximum conversion obtained in organic medium was 13.5 and 18.7%, using free and immobilized enzyme, respectively. The maximum conversion obtained in aqueous medium was 11.9 and 15.3%, using free and immobilized enzyme, respectively. To NRRL Y-7571 the maximum conversion obtained in organic medium was 16.7 and 18.2%, using free and immobilized enzyme, respectively. The maximum conversion obtained in aqueous medium was 15.2 and 16.8%, using free and immobilized enzyme, respectively.

ASSUNTO(S)

fructooligosaccharides planejamento experimental sintese experimental planning organic media

ACESSO AO ARTIGO

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