酶法醇解合成2-花生四烯酸单甘酯Enzymatic synthesis of 2-arachidonoylglycerol by ethanolysis

Abstract

2-花生四烯酸单甘酯（2-AG）是一种内源性大麻素，在神经、心血管和免疫等系统中具有一系列的生理活性。为实现2-AG的绿色高效制备，探究了脂肪酶催化醇解富含花生四烯酸的微生物油制备2-AG的方法。以2-单甘酯（2-MAG）含量为指标，通过单因素实验对酶法催化醇解反应条件进行了优化，并采用溶剂萃取法对产物进行纯化。结果表明：最佳反应条件为以Lipozyme 435脂肪酶为醇解脂肪酶、酶添加量4%（以油质量计）、油与无水乙醇物质的量比1∶ 40、叔丁醇为溶剂、油溶比2∶ 3、反应温度35 ℃、反应时间8 h，在最佳条件下粗产物中2-MAG含量为3363%；经溶剂萃取纯化后2-MAG的纯度达到了94.79%，其中2-AG含量为40.70%。 综上，酶法醇解富含花生四烯酸的微生物油可以获得高2-AG含量的2-MAG。2-Arachidonoylglycerol (2-AG) is an endogenous cannabinoid and exhibits a variety of biological activities in the central nervous, cardiovascular, and immune systems. To prepare 2-AG in a greener and efficient way, a lipase-catalyzed alcoholysis of microbial oil rich in arachidonic acid was used to synthesize 2-AG. With the 2-monoacylglycerol (2-MAG) content as an index, the reaction conditions of lipase-catalyzed alcoholysis were optimized by single factor experiment, and a solvent extraction method was employed to purify the product. The results showed that the optimal reaction conditions of lipase-catalyzed alcoholysis were as follows: Lipozyme 435 as alcoholysis enzyme, lipase dosage 4% (relative to oil mass), molar ratio of oil to anhydrous ethanol 1∶ 40, tert-butanol as solvent, ratio of oil to solvent 2∶ 3, reaction temperature 35 ℃ and reaction time 8 h. Under the optimal conditions, 2-MAG content in the crude product was up to 33.63%. The purity of 2-MAG after purification was up to 9479%, and the content of 2-AG was 40.70%. In conclusion, enzymatic alcoholysis of microbial oil rich in arachidonic acid can obtain 2-MAG with high 2-AG content.

Keywords

• 2-花生四烯酸单甘酯；脂肪酶催化；醇解；微生物油
• 2-arachidonolyglycerol; lipase-catalyzed reaction; alcoholysis; microbial oil