Abstract: The immobilization of Arthrobacter sp. lipase on zirconium nucleotide nanoparticles was investigated. The effect of immobilization time, pH value, buffer concentration, and lipase amount on the catalytic performance of the immobilized lipase in an organic system was studied. The results showed that the enzyme immobilized on zirconium-uridine monophosphate (30–50 nm) had the best catalytic performance for the resolution of 4-hydroxy-3-methyl-2-(2-propenyl)-2-cyclopenten-1-one. The optimal immobilization conditions were determined to be pH = 8.0, phosphate buffer concentration of 0.03 mol/L with the lipase/support mass ratio of 4 , and immobilization for 6 h. The activity recovery was as high as 6.8 fold of the free lipase and the enantioselectivity (E = 200) was improved (E = 85 for free lipase). Furthermore, the operational stability for the immobilized enzyme was greatly enhanced compared with the free enzyme. The residual activity was kept at 58.7% after 20 batch reactions, while that of the free enzyme was only 4%.

Key words: zirconium nucleotide, nanoparticle, Arthrobacter sp. lipase, immobilization, transesterification