非水相中酶法合成月桂酸木糖酯

Enzymatic synthesis of dodecanoic acid xylose ester in non-aqueous media

以月桂酸和木糖为原料,酯化合成月桂酸木糖酯。探讨了溶剂种类、糖酸摩尔比、分子筛用量、酶用量及反应时间对酯化率的影响,并用薄层层析(TLC)、硅胶柱层析、高效液相色谱(HPLC)、傅里叶红外光谱(FTIR)对反应产物进行了初步分离和鉴定。结果表明,酶促合成月桂酸木糖酯的最佳条件为:在无水异丙醇体系中,反应时间24 h,酶用量0.4%,分子筛用量40 g/L,糖酸摩尔比1∶2,在55℃下,月桂酸的酯化率可达98.70%;木糖和月桂酸木糖酯在展开剂为甲醇-水(体积比7∶3)时的Rf值分别为0.75和0.63;HPLC与FTIR分析表明反应产物中有酯键生成。

Dodecanoic acid xylose ester was synthesized by xylose and dodecanoic acid. The effects of solvent species,molar ratio of xylose to dodecanoic acid,dosage of molecular sieve,dosage of enzyme and reaction time on the esterification rate were investigated. Then the preliminary separation and identification of the reaction product were conducted by thin layer chromatography（ TLC）,silica gel column chromatography,HPLC and FTIR. The results showed that the esterification rate of dodecanoic acid could reach 98. 70% under the conditions of reaction time 24 h,reaction temperature 55 ℃,dosage of enzyme0. 4%,dosage of molecular sieve 40 g / L and molar ratio of xylose to dodecanoic acid 1∶ 2. The Rfvalues of xylose and dodecanoic acid xylose ester were 0. 75 and 0. 63 respectively when developing agent was methanol- water（ volume ratio 7∶ 3）. The analysis results of HPLC and FTIR indicated the formation of ester bond in the reaction product.