(R)-2-Phenoxy-propionic acid methyl ester (PPAM) is an important chiral precursor of aryloxy phenoxy propionate herbicides. The covalent immobilization of lipase from Aspergillus oryzae WZ007 and the catalysis of enantioselective (R, S)-PPAM resolution by the immobilized A. oryzae lipase (AOL) were investigated in this study. The primary amino resin LX-1000HA was selected as the support for the covalent immobilization of AOL. The Km and Vmax of the immobilized lipase were 1.97 mM and 4.84 × 103 μmol/mg min, respectively. The key reaction parameters (pH, temperature, rotation speed, and substrate concentration) for the lipase-catalyzed resolution of (R, S)-PPAM were optimized. An e.e.s of 99.5% and conversion rate of 50.8% were achieved under the optimal conditions of pH 7.5, 30 °C, and substrate concentration 500 mM. The immobilized lipase retained 87.3% of its initial activity after 15 cycles of the repeated experiments. The results demonstrated that the covalent immobilized AOL has potential industrial applications.

中文翻译：

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米曲霉共价固定脂肪酶对（R，S）-2-苯氧基丙酸甲酯的对映选择性拆分

（R）-2-苯氧基-丙酸甲酯（PPAM）是芳氧基苯氧基丙酸酯除草剂的重要手性前体。本研究研究了米曲霉WZ007的脂肪酶的共价固定和米曲霉脂肪酶（AOL）催化对映选择性（R，S）-PPAM拆分的催化作用。选择伯氨基树脂LX-1000HA作为AOL共价固定的载体。固定化脂肪酶的Km和Vmax分别为1.97 mM和4.84×103μmol/ mg min。优化了脂酶催化的（R，S）-PPAM分离的关键反应参数（pH，温度，转速和底物浓度）。在pH 7.5、30°C和底物浓度为500 mM的最佳条件下，ee达到99.5％，转化率达到50.8％。在重复实验的15个循环后，固定化的脂肪酶保留了其初始活性的87.3％。结果表明，共价固定的AOL具有潜在的工业应用。