Faculty of Industrial Chemistry and Environmental Engineering, University Politehnica Timişoara, Carol Telbisz 6, 300001 Timişoara, Romania.
Wageningen Food & Biobased Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
Biotechnol J. 2018 Jun;13(6):e1700629. doi: 10.1002/biot.201700629. Epub 2018 Mar 30.
Developments of past years placed the bio-based polyesters as competitive substitutes for fossil-based polymers. Moreover, enzymatic polymerization using lipase catalysts has become an important green alternative to chemical polymerization for the synthesis of polyesters with biomedical applications, as several drawbacks related to the presence of traces of metal catalysts, toxicity and higher temperatures could be avoided. Copolymerization of ϵ-caprolactone (CL) with four hydroxy-fatty acids (HFA) from renewable sources, 10-hydroxystearic acid, 12-hydroxystearic acid, ricinoleic acid, and 16-hydroxyhexadecanoic acid, was carried out using commercially available immobilized lipases from Candida antarctica B, Thermomyces lanuginosus, and Pseudomonas stutzeri, as well as a native lipase. MALDI-TOF-MS and 2D-NMR analysis confirmed the formation of linear/branched and cyclic oligomers with average molecular weight around 1200 and polymerization degree up to 15. The appropriate selection of the biocatalyst and reaction temperature allowed the tailoring of the non-cyclic/cyclic copolymer ratio and increase of the total copolymer content in the reaction product above 80%. The catalytic efficiency of the best performing biocatalyst (Lipozyme TL) is evaluated during four reaction cycles, showing excellent operational stability. The thermal stability of the reaction products is assessed based on TG and DSC analysis. This new synthetic route for biobased oligomers with novel functionalities and properties could have promising biomedical applications.
近年来的发展将生物基聚酯作为化石基聚合物的具有竞争力的替代品。此外,使用脂肪酶催化剂的酶聚合已成为合成具有生物医学应用的聚酯的重要绿色替代化学聚合方法,因为可以避免与痕量金属催化剂、毒性和更高温度相关的几个缺点。使用来自可再生资源的四种羟基脂肪酸(10-羟基硬脂酸、12-羟基硬脂酸、蓖麻油酸和 16-羟基十六烷酸)与 ε-己内酯(CL)共聚,使用商业可得的来自南极假丝酵母 B、嗜热丝孢菌和假单胞菌的固定化脂肪酶以及天然脂肪酶进行。MALDI-TOF-MS 和 2D-NMR 分析证实了具有约 1200 的平均分子量和聚合度高达 15 的线性/支化和环状低聚物的形成。生物催化剂和反应温度的适当选择允许定制非环/环共聚物的比例,并将反应产物中的总共聚物含量提高到 80%以上。评价了表现最佳的生物催化剂(Lipozyme TL)在四个反应循环中的催化效率,显示出优异的操作稳定性。基于 TG 和 DSC 分析评估了反应产物的热稳定性。这种具有新型功能和性能的生物基低聚物的新合成途径可能具有有前途的生物医学应用。