Comparison of lipase-catalyzed synthesis of cyclopentadecanolide under organic and biphasic systems

Abstract

Methyl 15-hydroxy-pentadecanate, which is made from Malana oleifera chum oil, is an ideal material to synthesize cyclopentadecanolide, an important macrocycle musk, with wide applications in the fields of perfume, cosmetic, food and medicine, etc. One kind of screened lipase from Candida sp.GXU08 strain was used to catalyze the synthesis of cyclopentadecanolide from methyl 15-hydroxy-pentadecanate. Traditionally, the catalytic reaction went on under organic solvent system, while an ultrasonic technology was innovatively used in water/organic solvent biphasic system to systhesize cyclopentadecanolide and received good catalytic effect. Both organic and biphasic systems had the same optimal conditions as: substrate concentration= 8 mmol/l, T= 40°C, ω = 180 r/min, pH= 6.0 to 6.5, ultrasonic time of 30 min, output power of 200 W and using lipase solution/lipase power and reaction system twice greatly increased the production of cyclopentadecanolide. It showed that, the maximum production of cyclopentadecanolide was 47.77×10^-3mg/U in biphasic system under the optimal conditions, which was 3.285 times of that in the organic system. It was also found that the production of cyclopentadecanolide in biphasic system was always higher than that in the organic system, which saved the process of freeze drying and improved the production of cyclopentadecanolide. It was verified that methyl 15-hydroxy-pentadecanate was directly cyclized into cyclopentadecanolide in the organic system while in the biphasic system, methyl 15-hydroxy-pentadecanate was hydrolysed into 15-hydroxypentadecanoic acid firstly and then cyclized into cyclopentadecanolide.

Key words: Lipase, cyclopentadecanolide, Malana oleifera chum, biphasic system, ultrasonic.