An insight on acyl migration in solvent-free ethanolysis of model triglycerides using Novozym 435

SANCHEZ D.; TONETTO G.; FERREIRA M.

JOURNAL OF BIOTECHNOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 220 p. 92 - 99

0168-1656

this work, the ethanolysis of triglycerides catalyzed by immobilized lipase was studied,focusing on the secondary reaction of acyl migration. The catalytic tests were performed in asolvent-free reaction medium using Novozym 435 as biocatalyst.The selected experimental variables were biocatalyst loading (5-20 mg), reaction time (30-90min), and chain length of the fatty acids in triglycerides with and without unsaturation (short(triacetin), medium (tricaprylin) and long (tripalmitin/triolein)).The formation of 2-monoglyceride by ethanolysis of triglycerides was favored by longreaction times and large biocatalyst loading with saturated short- to medium-chain triglycerides.In the case of long-chain triglycerides, the formation of this monoglyceride was widely limitedby acyl migration.In turn, acyl migration increased the yield of ethyl esters and minimized the content ofmonoglycerides and diglycerides. Thus, the enzymatic synthesis of biodiesel was favored bylong-chain triglycerides (which favor the acyl migration), long reaction times and largebiocatalyst loading.The conversion of acylglycerides made from long-chain fatty acids with unsaturation wasrelatively low due to limitations in their access to the active site of the lipase.