Podolean Iunia, Tudorache Madalina
Department of Organic Chemistry, Biochemistry and Catalysis, Faculty of Chemistry, University of Bucharest, 4-12 Regina Elisabeta Av., 030018 Bucharest, Romania.
Materials (Basel). 2024 Sep 14;17(18):4518. doi: 10.3390/ma17184518.
The present study is integrated in a global effort to capitalize waste cooking oil (WCO) into versatile compounds by introducing an oxirane ring into the unsaturated carbon chain of fatty acid residues (the epoxidation of double bound). Therefore, an enzymatic method was set up for the epoxidation of artificially adulterated WCO (SFw) and WCO under real conditions (SFr) derived from sunflower biomass. Commercial lipase (Novozyme, NZ) was used as a biocatalyst for generating the peracid requested by the epoxidation pathway. Optimum experimental conditions (e.g., 1.5 wt% NZ, 1:1:0.5 = HO/double bonds/peracid precursor (molar ratio) and 12 h reaction time) allowed for the conversion of 90% of the SFw substrate into products with an oxirane ring. Octanoic acid was selected as the best peracid precursor. The versatility of the developed system was tested for olive, milk thistle, hemp and linseed oils as both fresh and WCO samples. The characterization of the oil samples before and after the enzymatic epoxidation allowed for the evaluation of the system performance. SFw/SFr exhibited a better susceptibility to enzymatic epoxidation. In addition, the reusability of the biocatalytic system was investigated. Furthermore, different strategies, such as biocatalyst coating and the addition of organic solvents/buffers were applied, limiting enzyme leaching, for the better recovery of the biocatalyst activity.
本研究是全球努力的一部分，旨在通过将环氧乙烷环引入脂肪酸残基的不饱和碳链（双键环氧化），将废食用油（WCO）转化为多功能化合物。因此，建立了一种酶促方法，用于对人工掺假的WCO（SFw）和来自向日葵生物质的实际条件下的WCO（SFr）进行环氧化。商业脂肪酶（诺维信，NZ）用作生物催化剂，以生成环氧化途径所需的过酸。最佳实验条件（例如，1.5 wt% NZ、1:1:0.5 = HO/双键/过酸前体（摩尔比）和12小时反应时间）可使90%的SFw底物转化为带有环氧乙烷环的产物。辛酸被选为最佳过酸前体。对橄榄油、水飞蓟油、大麻油和亚麻籽油的新鲜样品和WCO样品测试了所开发系统的多功能性。对酶促环氧化前后的油样进行表征，以评估系统性能。SFw/SFr对酶促环氧化表现出更好的敏感性。此外，还研究了生物催化系统的可重复使用性。此外，还应用了不同的策略，如生物催化剂包衣和添加有机溶剂/缓冲液，以限制酶的浸出，从而更好地恢复生物催化剂活性。
