Department of Food Science and Biotechnology, Kyung Hee University, Yongin, 17104, Republic of Korea.
Graduate School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin, 17104, Republic of Korea.
Enzyme Microb Technol. 2019 Jan;120:84-90. doi: 10.1016/j.enzmictec.2018.10.006. Epub 2018 Oct 19.
Isoquercitrin (IQ, quercetin-3-O-β-d-glucopyranoside) has diverse biological functions, such as anti-oxidant and anti-cancer activity, but its use is limited by poor solubility and bioavailability. Enzymatically modified IQ (EMIQ) is a mixture of transglycosylated IQs that have better solubility and bioavailability than do quercetin and IQ. Two different enzymes, cyclodextrin glucanotransferase (CGTase) and amylosucrase (ASase), have the transglycosylation activity to produce EMIQ. Both enzymes produce a variety of EMIQs including IQ, IQ-glucoside (IQ-G1), IQ-diglucoside (IQ-G2), and IQ-triglucoside (IQ-G3). ASase had a higher bioconversion yield from IQ to EMIQ (97.6%) than did CGTase (76.8%). In addition, the yield of IQ-G3, which was the most bioavailable form, was higher with ASase (46%) than with CGTases (8%). Taken together, these results suggest that ASase can be used to synthesize EMIQ in a simple and specific process.
异槲皮苷（IQ，槲皮素-3-O-β-d-吡喃葡萄糖苷）具有多种生物学功能，如抗氧化和抗癌活性，但由于溶解度和生物利用度差，其应用受到限制。酶法修饰的异槲皮苷（EMIQ）是转糖苷化异槲皮苷的混合物，其溶解度和生物利用度均优于槲皮素和异槲皮苷。两种不同的酶，环糊精葡萄糖基转移酶（CGTase）和淀粉蔗糖酶（ASase），具有转糖苷化活性，可产生 EMIQ。两种酶都产生多种 EMIQs，包括 IQ、IQ-葡萄糖苷（IQ-G1）、IQ-二葡萄糖苷（IQ-G2）和 IQ-三葡萄糖苷（IQ-G3）。ASase 从 IQ 到 EMIQ 的生物转化率（97.6%）高于 CGTase（76.8%）。此外，ASase 产生的最具生物利用度的 IQ-G3 形式的产率（46%）高于 CGTase（8%）。综上所述，这些结果表明 ASase 可用于简单、特异性地合成 EMIQ。
