کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
70159 48813 2013 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Enzymatic activity studies of Pseudomonas cepacia lipase adsorbed onto copolymer supports containing β-cyclodextrin
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Enzymatic activity studies of Pseudomonas cepacia lipase adsorbed onto copolymer supports containing β-cyclodextrin
چکیده انگلیسی

Pseudomonas cepacia lipase (PCL) was immobilized onto polyurethane copolymers containing β-cyclodextrin (β-CD) via physisorption. The polymer bound PCL was characterized using an equilibrium sorption method, Fourier transform infrared (FTIR) spectroscopy with attenuated total reflectance (ATR), Raman spectroscopy, and powder X-ray diffraction (PXRD). The objective of this research was to investigate lipase immobilization onto polyurethane copolymers and an investigation of its enzymatic activity. The copolymers contain β-CD with two types of crosslinker units: 4,4′-dicyclohexylmethane diisocyanate (CDI) and 4,4′-diphenylmethane diisocyanate (MDI), respectively. Immobilization of PCL resulted in a pronounced increase in catalytic activity and stability of lipase (∼three-fold for CDI and ∼four-fold for MDI) in comparison with free lipase in aqueous solution. PCL exhibited remarkable hydrolytic activity over a range of pH (5–9) values, temperatures (25–65 °C), and solvents (mostly non-polar). The immobilized lipase was further used for the synthesis of n-butyl octanoate ester using n-butanol and octanoic acid. The immobilized lipase was successfully recycled four times while maintaining ∼75–80% esterification activity after the fourth catalytic cycle and exhibited appreciable stability for at least 30 days.

Figure optionsDownload as PowerPoint slideHighlights
► Physical immobilization of lipase onto microporous urethane copolymers substrates.
► Enhanced hydrolytic activity of immobilized lipase vs. free lipase.
► Catalytic activity over a wide pH, temperature and solvents conditions.
► Lipase immobilization provides tunable activity, stability, and recyclability.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Catalysis B: Enzymatic - Volume 87, March 2013, Pages 105–112
نویسندگان
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