Abstract:

In the supercritical CO2 state, the synthesis of lipid with SLS-type structure from the Rhizomucor miehei lipase
(Lipozyme RMIM)-catalyzed reaction between ethyl acetate and first-grade soybean oil was investigated. The effects of
enzyme concentration, reaction pressure, temperature and time on the conversion rate of ethyl acetate were examined by the
combined use of single factor design and response surface methodology. The results showed that the optimal parameters
for preparing SLS-type structured lipid were determined as follows: in the presence of 2.9% lipase RMIM, reaction at
49.0 ℃and 9.4 MPa for 13.1 h. Under these conditions, the conversion rate of ethyl acetate reached 36.1% and after
purification of the final product, a purity of 90.3% and a caloricity of 22.35 kJ/g (reduced by 42% as compared with that of
ordinary soybean oil) were obtained.

Key words: supercritical CO2, lipase, structured lipid, ethyl acetate conversion rate