کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1985983 1540236 2016 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Macromolecular cross-linked enzyme aggregates (M-CLEAs) of α-amylase
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Macromolecular cross-linked enzyme aggregates (M-CLEAs) of α-amylase
چکیده انگلیسی


• Biocompatible, biodegradable and eco-friendly cross-linkers were developed for α-amylase CLEAs.
• Dextran and chitosan M-CLEAs showed highest activity recovery as compared to glutaraldehyde CLEAs.
• Dextran M-CLEAs exhibited unchanged affinity with rapid starch hydrolytic activity.
• Thermal stability of M-CLEAs was expressed as half life, deactivation constant and energy.
• Changes in catalytic activity is influence of change in secondary structure in CLEAs preparation.

Macromolecular cross-linked enzyme aggregates (M-CLEAs) of α-amylase were prepared by precipitation and subsequent cross-linking. The non-toxic, biodegradable, biocompatible, renewable polysaccharide based macromolecular cross-linkers viz. agar, chitosan, dextran, and gum arabic were used as a substitute for traditional glutaraldehyde to augment activity recovery toward macromolecular substrate. Macromolecular cross-linkers were prepared by periodate mediated controlled oxidation of polysaccharides. The effects of precipitating agent, concentration and different cross-linkers on activity recovery of α-amylase CLEAs were investigated. α-Amylase aggregated with ammonium sulphate and cross-linked by dextran showed 91% activity recovery, whereas glutaraldehyde CLEAs (G-CLEAs) exhibited 42% activity recovery. M-CLEAs exhibited higher thermal stability in correlation with α-amylase and G-CLEAs. Moreover, dextran and chitosan M-CLEAs showed same affinity for starch hydrolysis as of free α-amylase. The changes in secondary structures revealed the enhancements in structural and conformational rigidity attributed by cross-linkers. Finally, after five consecutive cycles dextran M-CLEAs retained 1.25 times higher initial activity than G-CLEAs.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Biological Macromolecules - Volume 84, March 2016, Pages 69–78
نویسندگان
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