Lu Jike, Nie Kaili, Wang Fang, Tan Tianwei
Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, PR China.
Bioresour Technol. 2008 Sep;99(14):6070-4. doi: 10.1016/j.biortech.2007.12.045. Epub 2008 Feb 5.
The immobilized lipase Candida sp. 99-125 catalyzed methanolysis of glycerol trioleate was studied in twelve different solvents in order to deduce the solvent effect through an attempt to correlate the highest yield with such solvent properties as hydrophobicity (log P), dielectric constant (epsilon), and Hildebrand solubility parameter (delta). The results showed that the conversion of glycerol trioleate and yield of oleic acid methyl ester were quite dependent on the solvent. The catalyst lipase in various solvents also needed different optimum amount of water to keep its maximum activity, and generally this lipase in more hydrophobic solvents required more water. The correlation between the highest yield and log P value was found to be reasonable except deviation of data points of certain solvents, while no obvious correlation existed between the other two parameters, dielectric constant (epsilon) and Hildebrand solubility parameter (delta), and the enzyme activity. The study revealed that more hydrophobic solvents such as n-hexane or cyclohexane were more suitable solvents for Candida sp. 99-125 catalyzed transesterification of glycerol trioleate to oleic acid methyl ester.
为了通过尝试将最高产率与诸如疏水性（log P）、介电常数（ε）和希尔德布兰德溶解度参数（δ）等溶剂性质相关联来推断溶剂效应，研究了固定化脂肪酶假丝酵母99 - 125在十二种不同溶剂中催化三油酸甘油酯的甲醇解反应。结果表明，三油酸甘油酯的转化率和油酸甲酯的产率相当依赖于溶剂。各种溶剂中的催化剂脂肪酶也需要不同的最适水量来保持其最大活性，并且一般来说，这种脂肪酶在疏水性更强的溶剂中需要更多的水。发现除了某些溶剂的数据点有偏差外，最高产率与log P值之间的相关性是合理的，而其他两个参数，即介电常数（ε）和希尔德布兰德溶解度参数（δ）与酶活性之间没有明显的相关性。该研究表明，更疏水的溶剂如正己烷或环己烷是假丝酵母99 - 125催化三油酸甘油酯转化为油酸甲酯更合适的溶剂。
