麦芽糖醇脂肪酸酯的酶催化合成及表面张力测定

Enzyme-catalyzed Synthesis and Surface Tension Measurement of Maltitol Fatty Acid Esters

以脂肪酶为催化剂,以麦芽糖醇和脂肪酸为原料合成麦芽糖醇脂肪酸酯。通过考察原料配比、催化剂的用量、反应时间、溶剂用量等主要因素对反应的影响,确定最佳反应条件。结果表明,以脂肪酶Novozym 435为催化剂,脂肪酶用量为0.24g/mmol脂肪酸,溶剂丙酮的用量为10mL/mmol脂肪酸,麦芽糖醇:脂肪酸为2:1(mol/mol),在60℃条件下反应80h,脂肪酸的转化率为91%～95%。当麦芽糖醇脂肪酸酯溶液质量分数为0.06%时,表面张力为38～40mN/m。

Under the catalysis of Novozym 435 lipase,maltitol was reacted with each of two fatty acids,lauric acid and palmitic acid to synthesize maltitol fatty acid ester.The reaction between maltitol and lauric acid or palmitic acid was investigated with respect to the effects of four reaction conditions including maltitol/fatty acid molar ratio,reaction duration,amount of acetone as the reaction medium and enzyme amount.The optimal levels of these reaction conditions were determined as follows：enzyme amount 0.24 g/mmol fatty acid;acetone amount 10mL/mmol fatty acid;and maltitol/fatty acid molar ratio 2：1for a reaction duration of 80 h at 60℃,which gave a conversion ratio of fatty acid ranging from 91% to 95%.The 0.06% aqueous solutions of the two synthesized maltitol fatty acid esters under the above reaction conditions displayed a surface intension varying from 38 to 40 mN/m.