Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore.
Bioresour Technol. 2012 Nov;123:332-7. doi: 10.1016/j.biortech.2012.07.103. Epub 2012 Aug 4.
A novel concept and efficient method for producing biodiesel (FAME) from grease (15-40wt% free fatty acid, FFA) were developed by using tandem lipases for one-pot esterification of FFA and transesterification of triglyceride with methanol in a solvent-free system. Combining immobilized Candida antarctica lipase B (CALB) (Novozyme 435) favoring the esterification and immobilized Thermomyces lanuginosus lipase (TLL) (Lipozyme TLIM) preferring the transesterification at 2:8 (wt/wt) gave FAME in 80% yield, being better than that with Novozyme 435 or Lipozyme TLIM. Recombinant Escherichia coli (Calb/Tll) co-expressing CALB and TLL was engineered as a more efficient tandem-lipases system. Using wet or dry cells (4wt%) gave FAME in 87% or 95% yield, which is much better than that with E. coli cells expressing either CALB or TLL alone. Cells of E. coli (Calb/Tll) were recycled for five times and retained 75% productivity, thus being practical for producing biodiesel from grease.
开发了一种从油脂（15-40wt%游离脂肪酸，FFA）生产生物柴油（FAME）的新概念和有效方法，该方法采用串联脂肪酶在无溶剂体系中进行一锅法酯化FFA 和甘油三酯与甲醇的酯交换。固定化南极假丝酵母脂肪酶 B（CALB）（诺维信 435）有利于酯化，固定化嗜热脂肪芽孢杆菌脂肪酶（TLL）（Lipozyme TLIM）有利于酯交换，在 2:8（wt/wt）的比例下，生物柴油的产率达到 80%，优于诺维信 435 或 Lipozyme TLIM。共表达 CALB 和 TLL 的重组大肠杆菌（Calb/Tll）被设计为更有效的串联脂肪酶系统。使用湿细胞或干细胞（4wt%）可获得 87%或 95%的生物柴油产率，明显优于单独表达 CALB 或 TLL 的大肠杆菌细胞。大肠杆菌（Calb/Tll）细胞可回收使用五次，保留 75%的生产力，因此可用于从油脂生产生物柴油。
