Lv Wen, Wu Chunjian, Lin Sen, Wang Xuping, Wang Yonghua
School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, P. R. China.
Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, P. R. China.
ACS Omega. 2021 Mar 27;6(13):9141-9152. doi: 10.1021/acsomega.1c00333. eCollection 2021 Apr 6.
Soybean oil deodorizer distillate (SODD) is well recognized as a good source of both biodiesel and high-value bioactive compounds of tocopherols, squalene, and phytosterols. To achieve a one-step synthesis of biodiesel and recovery of bioactive compounds from SODD, four commercial immobilized enzymes (Novozym 435, Lipozyme TLIM, Lipozyme RMIM, and Lipozyme RM) and one self-prepared immobilized lipase MAS1-H108A were compared. The results showed that immobilized lipase MAS1-H108A due to the better methanol tolerance and higher catalytic activity gave the highest biodiesel yield of 97.08% under the optimized conditions: molar ratio of 1:2 (oil/methanol), temperature of 35 °C, and enzyme loading of 35 U/g SODD, even after 10 persistent cycles without significant decrease of activity. Simultaneously, there was no loss of tocopherols and squalene in SODD during the enzymatic reaction. Pure biodiesel (characterized by fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR)) and a high concentration of bioactive compounds could be successfully separated by molecular distillation at 100 °C. In a word, this work provides an interesting idea to achieve environmentally friendly treatment of SODD by combining an enzymatic process and molecular distillation, and it is suitable for industrial production.
大豆油脱臭馏出物（SODD）是公认的生物柴油以及生育酚、角鲨烯和植物甾醇等高价值生物活性化合物的良好来源。为了实现从SODD一步合成生物柴油并回收生物活性化合物，比较了四种商业固定化酶（诺维信435、Lipozyme TLIM、Lipozyme RMIM和Lipozyme RM）和一种自制的固定化脂肪酶MAS1-H108A。结果表明，固定化脂肪酶MAS1-H108A由于具有更好的甲醇耐受性和更高的催化活性，在优化条件下（油/甲醇摩尔比为1:2、温度为35℃、酶负载量为35 U/g SODD）生物柴油产率最高，达97.08%，即使经过10次连续循环活性也无显著下降。同时，在酶促反应过程中SODD中的生育酚和角鲨烯没有损失。通过在100℃下进行分子蒸馏可成功分离出纯生物柴油（通过傅里叶变换红外光谱（FT-IR）和核磁共振（NMR）表征）和高浓度的生物活性化合物。总之，这项工作提供了一个有趣的思路，即将酶促过程与分子蒸馏相结合实现对SODD的环境友好处理，且适用于工业生产。
