固定化脂肪酵素於幾丁聚醣/氧化石墨烯複合膜並應用於酵素膜反應器

在現代化工產業中，酵素催化反應具有高度專一性並被廣泛認定為對環境友善的綠能製程。在工業酵素中，脂肪酶已廣泛使用，可以應用於酯類水解、酯類合成與甘油酯轉酯化(transesterification)等反應，本研究領域之重點為透過結合固定化與薄膜技術，以達到同時催化與分離的效果。本實驗利用幾丁聚醣具有優異的生物相容性，以及氧化石墨烯擁有良好之機械強度與表面富有含氧官能基可提供酵素固定化之特性，將皺褶假絲酵母脂肪酶固定化於幾丁聚醣/氧化石墨烯複合薄膜，期望此新穎的複合材料相較於傳統純幾丁聚醣高分子擁有較佳之固定化活性及操作特性。並比較1-ethyl- (3-dimethylaminopropyl) carbodiimide(EDC) / N-hydroxyl succinimide(NHS)兩種偶聯劑及單純EDC偶聯劑表面改質對固定化活性之影響，探討不同混合比例之CS/GO複合膜的最佳固定化條件及操作穩定度，利用傅立葉紅外光譜(FTIR)及X射線光電子能譜儀(XPS)於固定化之表面鑑定。此外，探討不同比例之氧化石墨烯添加量對整體複合薄膜之膨潤現象之及機械強度，並建立一簡易反應器模組，將測試不同複合薄膜應用於長期操作下之轉化率，利用場發式電子顯微鏡(FE-SEM)觀察操作前後之表面形貌改變，利用滲透蒸發分離程序，測試複合膜於25 ℃、90 wt%乙醇/水之分離效能，透過結合酵素活性及薄膜分離兩者之優點，期望後續仍可透過更改反應器設計，將此薄膜推廣於水解、酯化及轉酯化等不同之酵素膜反應器之應用。

關鍵字

脂肪酶；固定化；幾丁聚醣；氧化石墨烯；複合薄膜；酵素膜反應器

並列摘要

In modern day chemical engineering processes, enzyme based catalysis is considered highly specific and environmental-friendly option. Among industrial enzymes, lipase are widely used in hydrolysis, esterification and transesterification processes. Combination of immobilization enzyme technology and membrane fabrication technology to increase enzyme efficiency had been a research focus for simultaneous catalysis and separation. In this work, lipase from porcine pancreas and Candida rugose were immobilized onto chitosan/graphene oxide composite membrane to verify this novel material for membrane enzyme bioreactor. Since the graphene oxide have superior mechanical properties and active functional groups for enzymes to interact, it was first hypothesized that the composite membrane would show improved operational characteristics over traditional chitosan based immobilization strategy. To immobilized the enzymes onto these membranes, 1-ethyl-(3-dimethylaminopropyl) carbodiimide(EDC) and N-hydroxyl succinimide (NHS) coupling agents were applied and compared to achieve optimized result for lipase activity after immobilization. FTIR and XPS were used to analyze the surface after modification. Besides, ratios of added GO would influence the membranes swelling ratio and parameters regarding mechanical strength of membranes were also investigated. Furthermore, the mass transfer characteristics of the composite membranes was determined through pervaporation experiments. Eventually, morphologies of the CS/GO composite membrane were characterized using the FESEM before and after prolonged operation to confirm the enhanced membrane integrity. Through combining the advantages of both the membrane technique and biocatalyst, we expected that this composite membrane could be applied in modular enzymatic membrane bioreactors on hydrolysis, esterification and transesterification reaction.

並列關鍵字

lipase ； immobilization ； chitosan ； graphene oxide ； composite membrane ； enzymatic membrane bioreactors

參考文獻

70. 林煜凱, Enhancing esterification by pervaporation using membrane reactor of graphene oxide/chitosan composite membrane. 臺灣大學化學工程學研究所學位論文, 2015.

1. Leung, D.Y.C., X. Wu, and M.K.H. Leung, A review on biodiesel production using catalyzed transesterification. Applied Energy, 2010. 87(4): p. 1083-1095.

3. Lloyd A. Nelson, T.A.F., William N. Marmer, Lipase-catalyzed production of biodiesel.pdf. 1996.

4. Zhang, W., et al., Lipase immobilized catalytically active membrane for synthesis of lauryl stearate in a pervaporation membrane reactor. Bioresour Technol, 2014. 172: p. 16-21.

5. Fang, Y., et al., Polymer materials for enzyme immobilization and their application in bioreactors. BMB Rep, 2011. 44(2): p. 87-95.

國際替代計量

固定化脂肪酵素於幾丁聚醣/氧化石墨烯複合膜並應用於酵素膜反應器

全文下載

主題瀏覽