Antioxidant and Antidiabetic Effects of Flavonoids: A Structure-Activity Relationship Based Study

Table 3

IC₅₀ values of flavonoids for α-glucosidase and DPP-4 inhibition assays.

Samples	α-Glucosidase (µg/mg)	DPP-4 (µg/mg)
Quercetin (commercial)		—
Sitagliptin	—
Wogonin	>100	>100
Methyl ether (wogonin)	NA	>100
Acetate (wogonin)	>100	NA
Techtochrysin	>100	>100
8-Hydroxy-7-methoxyflavone	>100	>100
Chrysin	>100	NA
Norwogonin	>100	>100
Acetate (norwogonin)	NA	>100
Isoscutellarein
Hypolaetin
Kaempferol
Quercetin
(+)-Catechin	NA	NA
(−)-Epicatechin	NA	NA

Values represent mean ± SEM (), NA: not active; capital letters represent significant difference based on Tukey’s test () and small letters represent significant difference based on Dunnett’s test ().