Enzymatic esterification of (−)‐menthol with lauric acid in isooctane by sorbitan monostearate‐coated lipase from Candida rugosa

Abstract

Esterification of (−)‐menthol and (±)‐menthol with lauric acid in isooctane was successfully catalyzed by a commercial nonioic surfactant (sorbitan monosterate)‐coated lipase from Candida rugosa (Lipase AY “Amano” 30) at the molar ratio of 1∶1 and at 35°C using 1.5 g enzyme/g (−)‐menthol and 0.1‐g molecular sieves. After 1 h, molar conversion of (−)‐menthol reached 81%. Equilibrium was reached after ca. 4 h, giving a (−)‐menthol molar conversion of 94%. Under the same conditions, native lipase catalyzed the esterification of (−)‐menthol and lauric acid to yield a molar conversion of 93% after 72 h. Coating the lipase with sorbitan monosterate increased the esterification rates of both (−)‐menthol and (±)‐menthol with lauric acid. After 6 h, the molar conversions of (−)‐menthol and (±)‐menthol were 94, and 62%, respectively.

Deep Eutectic Solvents for Enzymatic Esterification of Racemic Menthol

“…When the esterification of rac-menthol with lauric acid is carried out in organic solvents, longer times are needed to achieve comparable conversion values. 42 From the standpoint of separation, the (2:1) M/LA DES is the most convenient. If the enzyme were 100% selective, it would convert only (−)-menthol and consume all of the lauric acid present, thereby facilitating post-reaction separation.…”

“…In the (3:1) DES, 16% of rac- menthol were converted at 3 h reaction, out of a maximum allowed 33% because of the concentration of the limiting reagent. When the esterification of rac -menthol with lauric acid is carried out in organic solvents, longer times are needed to achieve comparable conversion values . From the standpoint of separation, the (2:1) M/LA DES is the most convenient.…”

“…4 CRL is reported to be most selective of the lipases tested toward (−)-menthol. It has already been used to catalyze the esterification of rac-menthol with lauric acid 14 (Figure 1). This reaction also produces water.…”

Chiral Separation by a Pseudo Membrane in a Triple‐Laminar Flow with a Microfluidic Contactor

“…% ratio. [18] The concentration of the substrate (ibuprofen) in the feed stream was 20 mm based on the racemic mixture. The receiving phase was also composed of 0.94 mm of an aqueous H 2 SO 4 solution as a hydrolysis catalyst.…”

Enzymatic esterification of DL‐menthol with propionic acid by lipase from Candida cylindracea

“…Enantiomeric resolution of L ‐menthol and preparation of L ‐menthol esters from racemic DL ‐menthol are problems of interest to the flavor and fragrance industries. Candida rugosa lipase (Crl)‐catalyzed esterification of racemic menthol in organic solvents and emulsions has been investigated extensively 10–15. Orlich et al 10 have studied the Crl‐catalyzed reactions in nonionic W/O‐microemulsions with a technical surfactant, Marlipal O13‐60.…”