Ln. Yee et al., LIPASE PS-CATALYZED TRANSESTERIFICATION OF CITRONELLYL BUTYRATE AND GERANYL CAPROATE - EFFECT OF REACTION PARAMETERS, Journal of the American Oil Chemists' Society, 74(3), 1997, pp. 255-260
Pseudomonas sp. lipase PS was immobilized by adsorption and tested for
its ability to catalyze the synthesis of citronellyl butyrate and ger
anyl caproate by transesterification in n-hexane. The reaction paramet
ers investigated were: enzyme load, effect of substrate concentration,
added water, temperature, rime course, organic solvent, pH memory, an
d enzyme reuse. Yields as high as 96 and 99% were obtained for citrone
llyl butyrate and geranyl caproate, respectively, with 300 units (appr
ox. 15% w/w of reactants) of lipase PS. Increasing amounts of terpene
alcohol inhibited lipase activity, while excess acyl donor (triacylgly
cerol) concentration enhanced ester production. Optimal yields were ob
tained at temperatures from 30-50 degrees C after 24-h incubation time
. Yields of 90 and 99% were obtained for citronellyl and geranyl ester
s, respectively, with 2% added water. Solvents with log P values great
er than or equal to 2.5 showed the highest conversion yields. pH 7 and
6-8 seemed to be ideal for citronellyl butyrate and geraniol caproate
, respectively. The lipase remained active after reusing 12 times.