Immobilization of Lecitase® Ultra for production of flaxseed oil-based diacylglycerols by glycerolysis and its operational stability

Abstract

Lecitase® Ultra (LU) was immobilized by adsorption on a macroporous resin and characterized. Meanwhile, the obtained immobilized lipase LXTE-1000-LU was applied in diacylglycerol (DAG) preparation, and the glycerolysis catalytic stability was also investigated. At pH 7.0, resin amount 2.5 g, and adsorption time of 2 h, an immobilization efficiency (IE) of 89.98% could be achieved. The storage stability was promoted after immobilization, in which the lipase activity reached more than 85% after 60 days of storage at 4 °C and 25 °C individually compared to its initial state. Furthermore, 41.31% of flaxseed oil-based DAG was obtained after the glycerolysis reaction using LXTE-1000-LU as the catalyst. Under prolonged reaction, the lipase protein content decreased from 17.91 mg/g to 6.99 mg/g, and significant changes in the secondary confirmation of the protein were also observed, leading to the catalytic activity being reduced.