以中链脂肪酸正辛酸为酰基供体，在有机相体系中利用脂肪酶催化酯化反应合成L-抗坏血酸辛酸酯。根据初步试验结果，选取对L-抗坏血酸酯化转化率影响显著的因素，进行响应面试验设计，建立回归模型，得到最优参数组合。结果表明：反应时间、反应温度、反应时间和反应温度的交互作用以及反应时间和底物浓度的交互作用对 L -抗坏血酸酯化转化率均有显著影响(p <0.05)，回归模型可用。 L-抗坏血酸辛酸酯酶法合成最优工艺条件为反应时间11.45 h、底物(L-抗坏血酸)浓度0.24 mol/L、反应温度55.3℃、脂肪酶用量(以L-抗坏血酸质量计)19.18%，此条件下L-抗坏血酸酯化转化率可达83.31%。产物经IR、MS、1 H NMR和13 C NMR结构表征，证实正辛酸被引入到了L-抗坏血酸的第6位羟基上。%L-ascorbyl octanoate was synthesized through lipase-catalyzed esterification in organic sys-tem with mid-chain fatty acid n-octanoic acid as acyl donor. The reaction parameters that highly influ-enced the conversion rate of L-ascorbic acid were selected as main variables to design the response sur-face experiment on the basis of preliminary experiments, then a regression model was established and the optimal synthesis conditions were obtained. The results indicated that reaction time, reaction tempera-ture, interaction between reaction time and reaction temperature and interaction between reaction time and substrate concentration had significant effects on the conversion rate of L-ascorbic acid ( p<0 . 05 ) , and the regression model could be used to predict the conversion rate of L-ascorbic acid. The optimal enzymatic synthesis conditions of L-ascorbyl octanoate were obtained as follows:reaction time 11. 45 h, substrate(L-ascorbic acid) concentration 0. 24 mol/L, reaction temperature 55. 3℃, dosage of lipase ( based on the mass of L-ascorbic acid) 19. 18%. Under these conditions,the conversion rate of L-ascor-bic acid reached 83. 31%. In addition, the product was characterized by IR, MS, 1 H NMR and 13 C NMR, and the result showed that n-octanoic acid was introduced into the sixth hydroxyl of L-ascorbic acid.
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