Pei Jianjun, Chen Anna, Zhao Linguo, Cao Fuliang, Ding Gang, Xiao Wei
Jiangsu Key Lab for the Chemistry & Utilization of Agricultural and Forest Biomass , Nanjing 210037, China.
Jiangsu Kanion Pharmaceutical Co., Ltd. , Lianyungang, Jiangsu Province 222001, China.
J Agric Food Chem. 2017 Jul 26;65(29):6042-6048. doi: 10.1021/acs.jafc.7b02320. Epub 2017 Jul 10.
Hyperoside exhibits many biological properties and is more soluble in water than quercetin. A uridine 5'-diphosphate (UDP) galactose regeneration system and one-pot synthesis of hyperoside was described herein. Glycine max sucrose synthase (GmSUS) was coupled with Escherichia coli UDP-galactose 4-epimerase (GalE) to regenerate UDP-galactose from sucrose and UDP. Petunia hybrida glycosyltransferase (PhUGT) with high activity toward quercetin was used to synthesize hyperoside via the UDP-galactose regeneration system. The important factors for optimal synergistic catalysis were determined. Through the use of a fed-batch operation, the final titer of hyperoside increased to 2134 mg/L, with a corresponding molar conversion of 92% and maximum number of UDP-galactose regeneration cycles (RC) of 18.4 under optimal conditions. Therefore, the method described herein for the regeneration of UDP-galactose from UDP and sucrose can be widely used for the glycosylation of flavonoids and other bioactive substances.
金丝桃苷具有多种生物学特性，且比槲皮素更易溶于水。本文描述了一种尿苷5'-二磷酸（UDP）半乳糖再生系统以及金丝桃苷的一锅法合成。大豆蔗糖合酶（GmSUS）与大肠杆菌UDP-半乳糖4-表异构酶（GalE）偶联，从蔗糖和UDP再生UDP-半乳糖。对槲皮素有高活性的矮牵牛糖基转移酶（PhUGT）通过UDP-半乳糖再生系统用于合成金丝桃苷。确定了最佳协同催化的重要因素。通过采用补料分批操作，在最佳条件下，金丝桃苷的最终产量提高到2134 mg/L，相应的摩尔转化率为92%，UDP-半乳糖的最大再生循环次数（RC）为18.4。因此，本文所述的从UDP和蔗糖再生UDP-半乳糖的方法可广泛用于黄酮类化合物和其他生物活性物质的糖基化。
