Flavonoids for controlling starch digestion: structural requirements for inhibiting human alpha-amylase.
In this study we investigated the structural requirements for inhibition of human salivary alpha-amylase by flavonoids. Four flavonols and three flavones, out of the 19 flavonoids tested, exhibited IC50 values less than 100 microM against human salivary alpha-amylase activity. Structure-activity relationships of these inhibitors by computational ligand docking showed that the inhibitory activity of flavonols and flavones depends on (i) hydrogen bonds between the hydroxyl groups of the polyphenol ligands and the catalytic residues of the binding site and (ii) formation of a conjugated pi-system that stabilizes the interaction with the active site. Our findings show that certain naturally occurring flavonoids act as inhibitors of human alpha-amylase, which makes them promising candidates for controlling the digestion of starch and postprandial glycemia.
Lo Piparo
Elena
E
Nestlé Research Center, Vers-chez-les-Blanc, PO Box 44, CH-1000 Lausanne 26, Switzerland. elena.lopiparo@rdls.nestle.com
Scheib
Holger
H
Frei
Nathalie
N
Williamson
Gary
G
Grigorov
Martin
M
Chou
Chieh Jason
CJ
D020134:Catalytic Domain; D004063:Digestion; D047309:Flavones / Q000737:chemistry*; D044948:Flavonols / Q000737:chemistry*; D006801:Humans; D006860:Hydrogen Bonding; D008024:Ligands; D008958:Models, Molecular; D011487:Protein Conformation; D012463:Saliva / Q000201:enzymology; D013213:Starch / Q000378:metabolism*; D013329:Structure-Activity Relationship; D000516:alpha-Amylases / Q000037:antagonists & inhibitors* / Q000737:chemistry
D047309:Flavones; D044948:Flavonols; D008024:Ligands; D013213:Starch; D000516:alpha-Amylases