Lipase-Ca2+ hybrid nanobiocatalysts through interfacial protein-inorganic self-assembly in deep-eutectic solvents (DES)/water two-phase system for biodiesel production

The production of biodiesel catalyzed by lipase has the advantages of simple process, low energy consumption, and low wastewater treatment requirements. However, low activity, poor stability, and difficulty in recycling still limit the application of lipase in production of biodiesel. Herein, a novel lipase hybrid biocatalyst with superior catalytic activity and stability (lipase from Aspergillus oryzae CJLU-3, [email protected] in DES) was developed by dual activation of Ca2+ and interfacial effect of deep-eutectic solvents (DES)/water two-phase system. [email protected] in DES exhibited significantly enhanced enzymatic activity with a Kcat/Km value of 692 s−1 mM−1 and excellent thermostability, tolerance to chemical denaturants, substrate selectivity, and reusability compared with free lipase. Recovery activity of the prepared hybrid biocatalyst in pure water system ([email protected]) and [email protected] in DES was 195% and 250% using p-NPL as substrate, respectively. [email protected] in DES exhibited about 253% of the original activity after 100 days of storage, while free AOCL, [email protected] almost completely lost activity. The FAME content in product biodiesel catalyzed from soybean oil by [email protected] was only 60%, However, the FAME content catalyzed by [email protected] in DES reached 87%, and could be maintained at 50% even after 10 cycles.