کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
35237 45082 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Enhancement of Novozym-435 catalytic properties by physical or chemical modification
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
Enhancement of Novozym-435 catalytic properties by physical or chemical modification
چکیده انگلیسی

Physical (ionic exchange of ionic polymers) or chemical (aminoethylamidation, succinylation, hydroxyethylamidation) modifications of Novozym 435 have been performed and the resulting biocatalysts have been assayed in diverse reactions. The coating of the immobilized enzyme with dextran-sulphate via ionic exchange permitted to increase the asymmetric factor of the biocatalyst from A = 13 (ee = 83%) to 24 (ee > 90%) in the hydrolysis of 3-phenylglutaric acid dimethyl diester, producing the (R)-monomethyl ester. The chemical succinylation of Novozym 435 permitted to enhance the biocatalyst enantiospecificity from E = 1 to 13 in the hydrolysis of (±)-mandelic acid methyl ester. In the hydrolysis of (±)-2-O-butyryl-2-phenylacetic acid, the enantiospecificity of Novozym 435 was very high towards the S-enantiomer (E > 100) but it was inverted after the chemical hydroxyethylamidation of the immobilized enzyme (E = 6.6 towards R-enantiomer).Thus, these simple protocols seem to be a very powerful tool to generate a library of biocatalysts from Novozym 435 with very different catalytic properties.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Process Biochemistry - Volume 44, Issue 2, February 2009, Pages 226–231
نویسندگان
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