Immobilization of Y. lipolytica lipase and the continuous synthesis of geranyl propionate

Abstract

In this study, Y. lipolytica lipase LIP2 (Lip2) was immobilized on the macroporous adsorptive resin DA201-C in n-heptane and then used to catalyze the continuous synthesis of geranyl propionate in a continuous stirred tank reactor (CSTR). With the lipase loading of 0.01 g/g resin, 25 °C and adsorption for 3 h, the immobilization efficiency can be up to 98.6% and the synthetic activity of the lipase was 690.8 U/g after immobilization, representing an increase of 28.5% compared with the free lipase (synthetic activity 537.2 U/g). The immobilized Lip2 was used to generate geranyl propionate in CSTR, the continuous production of geranyl propionate was performed with 3 g of immobilized Lip2 at 35 °C. At the flow rate of 6 mL/h the process can maintain its steady state at least for 12 h, which was about three times of the average residence time, and the esterification ratio of 72.8% could be attained. Finally, FT-IR and NMR were used to identify the ester.