Solvent-Free Alcoholysis of Tripalmitin to Produce 2-Monoglyceride as Precursor for 1, 3-Oleoyl-2-Palmitoylglycerol

Abstract

2-monoglyceride (2-MAG) was essential to produce high purity of 1, 3-Oleoyl-2-palmitoylglycerol (OPO), an important infant formula additive. Traditional synthesis of 2-MAG requires chemical solvent to solve the high melting point substrate, yielding the risk of solvent residue in OPO. This paper developed a solvent-free synthesis route of 2-MAG by alcoholysis of high melting point tripalmitin (PPP). Ethyl palmitate (EP), one of the reaction byproducts, was added in the beginning of alcoholysis process to promote the solubleness of high melting point PPP, avoiding the addition of toxic chemical solvent. The product of alcoholysis was separated by two-step molecular distillations. Separated DAG was used to produce 2-MAG and the final conversion of 2-MAG reached about 85.90%, with the purity of 92.36%. 2-MAG was trans-esterified to OPO with ethyl oleate, and the yield of OPO was up to 85.06% with 80.17% palmitic acid located on sn-2 position. The solvent-free synthesis route avoids the usage of hazardous chemical solvents, providing safer infant formula additive.

Keywords: 1, 3-Oleoyl-2-palmitoylglycerol; 2-monoglyceride; Alcoholysis; Candida sp. 99-125; Monopalmitin; Solvent-free synthesis.