Advances in the biotechnological glycosylation of valuable flavonoids.
The natural flavonoids, especially their glycosides, are the most abundant polyphenols in foods and have diverse bioactivities. The biotransformation of flavonoid aglycones into their glycosides is vital in flavonoid biosynthesis. The main biological strategies that have been used to achieve flavonoid glycosylation in the laboratory involve metabolic pathway engineering and microbial biotransformation. In this review, we summarize the existing knowledge on the production and biotransformation of flavonoid glycosides using biotechnology, as well as the impact of glycosylation on flavonoid bioactivity. Uridine diphosphate glycosyltransferases play key roles in decorating flavonoids with sugars. Modern metabolic engineering and proteomic tools have been used in an integrated fashion to generate numerous structurally diverse flavonoid glycosides. In vitro, enzymatic glycosylation tends to preferentially generate flavonoid 3- and 7-O-glucosides; microorganisms typically convert flavonoids into their 7-O-glycosides and will produce 3-O-glycosides if supplied with flavonoid substrates having a hydroxyl group at the C-3 position. In general, O-glycosylation reduces flavonoid bioactivity. However, C-glycosylation can enhance some of the benefits of flavonoids on human health, including their antioxidant and anti-diabetic potential.
Department of Biology, Shanghai Normal University, 100 Guilin Rd, Shanghai 200234, China; Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany; Anhui Academy of Applied Technology, Suixi Road 312, 230031 Hefei, Anhui, China. Electronic address: jianboxiao@yahoo.com.
Jianbo
J
Xiao
Iovel Kutateladze Institute of Pharmacochemistry, Tbilisi State Medical University, 36 P. Sarajishvili st., 0159 Tbilisi, Georgia.
Tamar S
TS
Muzashvili
The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 139 Ruski Blvd., 4000 Plovdiv, Bulgaria.
Milen I
MI
Georgiev
D001709:Biotechnology / Q000379:methods*; D005419:Flavonoids / Q000737:chemistry / Q000378:metabolism; D005658:Fungi / Q000378:metabolism; D006027:Glycosides / Q000737:chemistry / Q000378:metabolism; D006031:Glycosylation; D060847:Metabolic Engineering / Q000379:methods*
D005419:Flavonoids; D006027:Glycosides
Flavonoid aglycones; Glycosides; Glycosylation; Glycosyltransferases; Metabolic engineering; Microbial biotransformation