抄録
Mono- and dilauroyl arabitols, ribitols, xylitols and sorbitols were synthesized at 50°C or 60°C by condensation catalyzed by an immobilized Candida antarctica lipase in acetone using a batch reactor or a packed-bed reactor. A system where a column packed with sugar alcohol and a packed-bed reactor with the immobilized lipase were connected in series was constructed for the continuous production of the acyl sugar alcohols. The concentrations of the mono- and dilauroyl esters of each sugar alcohol became almost constant at the mean residence times of 15 min or longer in the packed-bed reactor, and the reaction equilibrium constants for the formations of the mono- and dilauroyl sugar alcohols were estimated to be 1.2 and 0.42, respectively, irrespective of the sugar alcohols. The monolauroyl, monomyristoyl and monopalmytoyl arabitols, ribitols, xylitols and sorbitols were continuously produced using the system at 60°C, and the productivity was in the range of 1.3 to 2.0 kg/L-reactor/day except for the fatty acid esters of sorbitol. The emulsifier properties and anti-microbial abilities of the monoacyl sugar alcohols were examined. Monomyristoyl erythritol and xylitol were very effective anti-microbial agents against some thermophilic bacteria.
