Dai Dazhang, Xia Liming
Department of Chemical Engineering and Bioengineering, Zhejiang University, Hangzhou 310027, The People's Republic of China.
Appl Biochem Biotechnol. 2006 Jul;134(1):39-50. doi: 10.1385/abab:134:1:39.
The lipase from Penicillium expansum PED-03 (PEL) was immobilized onto modified ultrastable-Y (USY) molecular sieve and the resolution of (R, S)- 2-octanol was carried out in a bioreactor in nonaqueous media by the immobilized lipase. It was found that the conversion rate, enantiomeric excess (ee) value, and enantioselectivity (E) value of the resolution catalyzed by PEL immobilized on modified USY molecular sieve were much higher than those of the reaction catalyzed by free PEL and PEL immobilized on other supports. Immobilized on modified USY molecular sieve, the PEL exhibited obvious activity within a wider pH range and at a much higher temperature and showed a markedly enhanced stability against thermal inactivation, by which the suitable pH of the buffer used for immobilization could be "memorized." The conversion rate of the reaction catalyzed by PEL immobilized on modified USY molecular sieve reached 48.84%, with excellent enantioselectivity (average E value of eight batches >460) in nonaqueous media at "memorial" pH 9.5, 50 degrees C for 24 h, demonstrating a good application potential in the production of optically pure (R, S)-2-octanol.
将扩展青霉PED - 03（PEL）脂肪酶固定在改性超稳Y（USY）分子筛上，并在非水介质的生物反应器中利用固定化脂肪酶对（R，S）-2-辛醇进行拆分。结果发现，固定在改性USY分子筛上的PEL催化拆分反应的转化率、对映体过量（ee）值和对映选择性（E）值远高于游离PEL和固定在其他载体上的PEL所催化的反应。固定在改性USY分子筛上的PEL在更宽的pH范围内和更高的温度下表现出明显的活性，并且对热失活具有显著增强的稳定性，借此可“记忆”用于固定化的缓冲液的适宜pH。在“记忆”pH 9.5、50℃下反应24小时，固定在改性USY分子筛上的PEL催化反应在非水介质中的转化率达到48.84%，对映选择性优异（八批次平均E值>460），在光学纯（R，S）-2-辛醇的生产中显示出良好的应用潜力。
