Scalable synthesis of highly pure 2‐monoolein by enzymatic ethanolysis

Abstract

It has been reported that 2‐monoolein exhibits various biological activities. In this study, an enzymatic method is reported for the synthesis of highly pure 2‐monoolein by ethanolysis of oleic acid‐rich oil. The effects of solvent type, addition amounts of solvent and lipase, and reaction time on 2‐MAGs content in the crude reaction mixture were investigated. Under the optimized conditions, there was 37.6% (area/area) 2‐MAGs produced in the crude mixture. 2‐MAGs were obtained at 97–98% purity and 33.6% yield (w/w) after fractionation in 85% ethanol aqueous solution and hexane to fully remove impurities including DAGs, TAGs, and fatty acid ethyl esters. Subsequently, 2‐MAGs were purified further by two‐step crystallization in hexane to remove saturated and polyunsaturated 2‐MAGs to obtain pure 2‐monoolein. After the two‐step crystallization, 97.5% 2‐monoolein was obtained at 78.3% yield (w/w). Compared to previous methods, our method for the synthesis of 2‐monoolein is easier to scale up, obtain highly pure 2‐monoolein product and more economical. In addition, the study on the effect of solvent type suggests that selectivity of the lipase and acyl migration of 2‐MAGs may be affected by reaction solvent polarity.Practical application: Synthetic 2‐monoolein can be used as emulsifier and surfactant in food, pharmaceutical and cosmetic and other industries. In addition, 2‐monoolein has exhibited strong antioxidation and anti‐atherosclerotic properties in vitro and in a cellular model. Thus, 2‐monoolein has potential application in treating cardiovascular diseases.