کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6490151 | 1416963 | 2018 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Lipase-mediated direct in situ ring-opening polymerization of ε-caprolactone formed by a chemo-enzymatic method
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موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A novel method to synthesize poly(ε-caprolactone) (PCL) through a three-step, lipase-mediated chemo-enzymatic reaction from cyclohexanone using an immobilized lipase from Trichosporon laibacchii (T. laibacchii) CBS5791 was developed. The immobilized preparation with 1280 U· gâ1 used here was obtained by a method of purification and in situ immobilization where the crude intracellular lipase (cell homogenate) was subjected to partial purification by an aqueous two-phase system (ATPS) consisting of 12% (w/w) polyethylene glycol (PEG) 4000 and 13% (w/w) potassium phosphate (K2HPO4) and then in situ immobilization directly on diatomite from the top PEG-rich phase of ATPS. In this multi-step process, the ε-caprolactone (ε-CL) produced by lipase-mediated one-pot two-step chemo-enzymatic oxidation of cyclohexanone was directly subjected to in situ ring-opening polymerization (ROP) started by adding highly hydrophobic solvents. It is necessary to note that ε-CL synthesis and its subsequent ROP were catalyzed by the same lipase. The impact of various reaction parameters, e.g., solvent, cyclohexanone: hydrogen peroxide molar ratio, hydrogen peroxide forms and reaction temperature were investigated. Toluene was selected as a preferred solvent due to supporting the highest molecular weight (Mnâ¯=â¯2168) and moderate ε-CL conversion (65.42%). Through the optimization of reaction conditions, PCL was produced with a Mn of 2283 at 50â¯Â°C for 24â¯h. These results reveal that this lipase-mediated direct ring-opening polymerization of in situ formed ε-CL is an alternative route to the conventional synthesis of PCL.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Biotechnology - Volume 281, 10 September 2018, Pages 74-80
Journal: Journal of Biotechnology - Volume 281, 10 September 2018, Pages 74-80
نویسندگان
Yuanyuan Zhang, Peiyu Lu, Qinghua Sun, Tao Li, Lanjie Zhao, Xin Gao, Fanye Wang, Junhong Liu,