Synthesis of citronellyl esters catalyzed by immobilized lipase in solvent-free system

The enzymatic synthesis of citronellyl esters by esterification of citronellol and fatty acids in a solvent-free system was discussed using Candida rugosa lipase (CRL) absorbed on macroporous resin NKA as catalyst. The conditions of enzymatic synthesis of citronellyl esters was optimized, including the selectivity of acyl donor, reaction temperature, enzyme dosage, molar ratio of substrate and micro-water addition. The results showed that under the conditions of molar ratio of acid to alcohol 1, agitation speed 200 r/min, reaction temperature 50℃, the concentration of immobilized lipase 1 250 U/L, the addition of water 4 μL, citronellyl laurate and citronellyl oleate were achieved with esterification rate of 95.6% and 87.6%, respectively, after 10 h of reaction, which was more superior than that in organic solvent system.