Enzymatic production of 2-monoacylglycerol from olive pomace oil

Alcoholysis reaction of olive pomace oil (OPO) was performed by using an immobilized lipase from Candida antarctica, commercially called Novozyme 435 to produce 2-monoacylglycerol (2-MAG). Response surface methodology was applied to evaluate the effect of several variables in the alcoholysis reaction and optimize the reaction conditions by using a four factor, five level central composite rotatable design. The four major factors were chosen as reaction temperature (35–60 oC), time (4–10 h), enzyme load (10–18 wt %) and substrate mole ratio (ethanol:oil, 40:1–90:1). Best fitting models were successfully established for the produced 2-Monoacylglycerols by multiple regressions with backward elimination. The optimum reaction conditions were found as reaction temperature 35 oC; time 6 h; substrate mole ratio 65:1; and enzyme load 15%. Under these optimum conditions, the 2-MAG yield was predicted as 87.8%. The value of the optimum reaction yield predicted by the model (87.8 %) was close to its actual value obtained through experimentation (83.5 %). Recovery and purification of 2-MAGs from alcoholysis reaction mixture were performed by using two methods: solvent extraction and low temperature crystallization. After solvent extraction, 2-MAG was obtained at 97% purity with 87.7% recovery yield while these values were 93.7% and 69.2%, respectively, after low temperature crystallization.