Abstract Acid oils represent a low-cost feedstock for biodiesel synthesis. The aim of this work was to study a single-step enzymatic esterification and transesterification process for fatty acid ethyl esters (FAEEs) production employing acid oils, ethanol, and liquid lipase formulation. The effects of lipase source (CALB, Palatase 20000 L, Lipolase 100 L, and Callera Trans L), temperature and enzyme ratio were studied in the transesterification of refined soybean oil with ethanol. The highest yield esters content (97%) was obtained at 30 °C with 10% vol/vol of Lipolase 100 L. The ethanolysis of acid soybean oil, using soybean oils with different acid contents (acid value (AV): 8.5, 50, and 90), was investigated using 10% vol/vol of lipase at 30 °C. The highest esters content (71%) was obtained employing acid oil with AV 50 and Palatase 20,000 L. The results showed the significant performance of soluble lipases in transesterification reactions of acid oils aiming for FAEEs synthesis.

中文翻译：

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使用酸性大豆油和液体脂肪酶制剂的酶促脂肪酸乙酯合成

摘要 酸性油是生物柴油合成的低成本原料。这项工作的目的是研究使用酸性油、乙醇和液体脂肪酶制剂生产脂肪酸乙酯 (FAEE) 的单步酶促酯化和酯交换过程。研究了脂肪酶来源（CALB、Palatase 20000 L、Lipolase 100 L 和 Callera Trans L）、温度和酶比在精制豆油与乙醇的酯交换反应中的影响。在 30 °C 下使用 10% vol/vol Lipolase 100 L 获得最高的酯含量 (97%)。 酸性大豆油的乙醇分解，使用不同酸含量的大豆油（酸值 (AV)：8.5, 50和 90)，在 30 °C 下使用 10% vol/vol 的脂肪酶进行研究。最高的酯含量 (71%) 是使用 AV 50 和 Palatase 20,000 L 的酸性油获得的。