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

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 4.27 nm (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 1 h. 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 (10 mL olive oil, 1.66 mL methanol, and 1.5 mL 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. (C) 2014 Elsevier B.V. All rights reserved.