将活化醇盐水解法制备的SiO2纳米粒子分别与羰基还原酶(CR)和甲酸脱氢酶(FDH)进行共价固定化,固定化CR与FDH耦合,连续催化转化b-羟基苯乙酮制备(R)-苯基乙二醇,考察了NADH的再生与循环利用性.结果表明,纳米粒子固定化CR和FDH酶载量分别为3.32和5.55 mg/g,催化活性为游离酶的50%~60%,最适反应p H值分别为6.5和8.5,最适反应温度分别为40和45℃.耦合体系进行12批次反应,产物(R)-苯基乙二醇累积量达35.6 g/L,纳米粒子生产能力达178 g/g.纳米粒子固定化酶经简单离心收集后可重复利用.
Si O2 nanoparticles prepared by the alkoxide hydrolysis precipitation method were covalently immobilized with carbonyl reductase(CR) and formate dehydrogenase(FDH). The nanopartiles immobilized CR and FDH were coupled and used for continuous catalytic conversion of β-hydroxyacetophenone to optical purity(R)-phenyl-ethanediol, and in situ NADH regeneration and recycling analyzed. The results showed that the enzyme loading of nanopartiles immobilized CR and FDH was 3.32 and 5.55 mg/g, their catalytic capability 50%?60% of native enzyme, their optimal reaction p H value 6.5 and 8.5, and their optimal reaction temperature 40 and 45 ℃, respectively. The production of(R)-phenyl-ethanediol was accumulated as 35.6 g/L, and the productivity of unit nanoparticles 178 g/g, while the coupling system was carried out for 12 batches. The nanopartiles immobilized CR and FDH could be reused after collection with centrifugal separation.