College of Food Science and Technology, Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Guangdong Province Engineering Laboratory for Marine Biological Products, Guangdong Provincial Engineering Technology Research Center of Seafood, Key Laboratory of Advanced Processing of Aquatic Product of Guangdong Higher Education Institution, Guangdong Ocean University, Zhanjiang, 524088, China.
Guangzhou Institute of Energy Conversion, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Chinese Academy of Sciences, Guangzhou, 510640, China.
Appl Biochem Biotechnol. 2023 Jan;195(1):432-450. doi: 10.1007/s12010-022-04146-6. Epub 2022 Sep 10.
The enzymatic production of biodiesel from waste cooking oils (WCOs) offers a green and sustainable solution for the liquid fuel manufacture as well as waste resource recovery. In present study, liquid lipase was used to simplify the catalysis process, thereby reducing biodiesel production costs. An engineered Escherichia coli expressing Geobacillus thermocatenulatus lipase 2 (GTL2) was screened at an enzyme activity of 6.96 U/mg, after evaluating the propagating stability of the recombinant plasmids exceeding 86.11%. Through the beneficial feeding strategy and effective pH control, high-level production of GTL2 by fed-batch fermentation was achieved with an enzyme activity of 434.32 U/mg, which was almost 62 times that of shake flask fermentation. In addition, liquid GTL2 was used to prepare fatty acid methyl esters (FAMEs) using WCOs. The effects of the reaction time, catalyst loading, temperature, and methanol-to-oil molar ratio on FAMEs production using WCOs were explored, and a maximum FAMEs yield of 96.62% was achieved under optimized conditions. These results indicate that liquid GTL2 is a promising biocatalyst for efficient utilization of WCOs in the synthesis of biodiesel and provide a novel enzymatic process for biodiesel reducing the cost of production.
从废弃食用油（WCOs）中酶法生产生物柴油为液体燃料制造和废物资源回收提供了一种绿色可持续的解决方案。在本研究中，使用液体脂肪酶简化了催化过程，从而降低了生物柴油的生产成本。通过评估超过 86.11%的重组质粒的繁殖稳定性，筛选出一种酶活为 6.96 U/mg 的表达嗜热脂肪地芽孢杆菌脂肪酶 2（GTL2）的工程大肠杆菌。通过有益的补料策略和有效的 pH 控制，实现了高酶活 434.32 U/mg 的 GTL2 分批发酵生产，是摇瓶发酵的近 62 倍。此外，使用液体 GTL2 从废弃食用油中制备脂肪酸甲酯（FAMEs）。探讨了反应时间、催化剂用量、温度和甲醇与油摩尔比对利用废弃食用油生产 FAMEs 的影响，在优化条件下，FAMEs 的最大产率达到 96.62%。这些结果表明，液体 GTL2 是一种很有前途的生物催化剂，可有效地利用废弃食用油合成生物柴油，并为降低生物柴油生产成本提供了一种新的酶法工艺。
