Rationally designed Fe-MCM-41 by protein size to enhance lipase immobilization, catalytic efficiency and performance

Abstract

A three-dimensional structure of lipase protein was constructed by using homology modeling. Six different Fe-MCM-41 carriers were synthesized with different pore size based on the properties of the lipase examined. The relative activity of lipase from Yarrowia lipolytica (YYL) immobilized on Fe-MCM-41 with a pore size of 4.27nm (FM-4-YYL) reached 197% when compared with free lipase. This result was notably higher than that of YYL encapsulated in other forms of Fe-MCM-41. Moreover, FM-4-YYL has excellent thermal stability in that it can preserve nearly 80% of the initial activity after incubation at 60°C for 1h. In addition, immobilized lipases were used as catalysts for the transesterification of olive oil with methanol. The highest conversion yield (98%) was observed when FM-4-YYL was used as a biocatalyst for biodiesel (10mL olive oil, 1.66mL methanol, and 1.5mL water at 30°C for 4h). FM-4-YYL can be reused for nine cycles without significant loss in activity. The work demonstrates that the selection and modification of adsorbents based on enzyme protein properties is a very promising strategy for increasing stability and enhancing active the performance of biocatalysts for industrial production.