Jiang Jie-rong, Yuan Sheng, Ding Juan-fang, Zhu Shou-chuang, Xu Hai-dong, Chen Ting, Cong Xiao-dong, Xu Wen-ping, Ye Hui, Dai Yi-jun
Nanjing Research Center for Microbial Engineering and Technology, Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Science, Nanjing Normal University, 1 Wenyuan Rd, Nanjing, 210046, People's Republic of China.
Appl Microbiol Biotechnol. 2008 Dec;81(4):647-57. doi: 10.1007/s00253-008-1683-z. Epub 2008 Sep 16.
Microbacterium oxydans strain NJ 6 isolated from soil samples converted puerarin into two novel compounds, puerarin-7-O-glucoside and puerarin-7-O-isomaltoside, via an unreported O-glycosylation of the phenolic hydroxyl group at the 7-position of puerarin. Sucrose, maltotriose, and maltose could be used as glucosyl donors for glycosylation of puerarin, but uridine-diphosphate glucose, glucose, fructose, lactose, cyclodextrin, and starch could not. Regardless of the position of B-ring in the (iso)flavonoids core structure, the glycosylation of the phenolic hydroxyl group at the 7-position of (iso)flavonoids was governed by the presence or absence of a glucosyl residue at 8-C. The apparent solubility of puerarin-7-O-glucoside and puerarin-7-O-isomaltoside was approximately 18 and 100 times that of natural puerarin, respectively. Like parent puerarin, puerarin-7-O-glucoside maintained its physiological ability to relax the contractions of isolated rat thoracic aortic rings in vitro induced by phenylephrine. However, puerarin-7-O-glucoside was able to maintain higher plasma concentrations and have a longer mean residence time in the blood than the parent puerarin.
从土壤样品中分离得到的氧化微杆菌NJ 6菌株，通过对葛根素7位酚羟基进行一种未报道的O-糖基化反应，将葛根素转化为两种新化合物，即葛根素-7-O-葡萄糖苷和葛根素-7-O-异麦芽糖苷。蔗糖、麦芽三糖和麦芽糖可作为葛根素糖基化反应的葡萄糖基供体，但尿苷二磷酸葡萄糖、葡萄糖、果糖、乳糖、环糊精和淀粉则不能。无论（异）黄酮核心结构中B环的位置如何，（异）黄酮7位酚羟基的糖基化反应受8-C位是否存在葡萄糖基残基的调控。葛根素-7-O-葡萄糖苷和葛根素-7-O-异麦芽糖苷的表观溶解度分别约为天然葛根素的18倍和100倍。与母体葛根素一样，葛根素-7-O-葡萄糖苷在体外保持了其舒张苯肾上腺素诱导的离体大鼠胸主动脉环收缩的生理能力。然而，与母体葛根素相比，葛根素-7-O-葡萄糖苷能够维持更高的血浆浓度，并且在血液中的平均驻留时间更长。
