Table 3.

Polyphenols regulates dipeptidyl peptidase IV (DPP-IV) activity.

Polyphenolic Compounds	Effective Concentration	Detection Assay	Effect on DPP-IV Activity	Possible Mechanism
Bis-pyrano prenyl isoflavone [208]	100 μM	DPP-4 fluorometric assay	53% inhibition	Not available
Rutin [209]	IC50: 0.485 mM	DPP-4 fluorometric assay	50% inhibition	Not available
Eriocitrin [207,209]	IC50: 5.44 mM; 10.36 ± 0.09 μM	DPP-4 fluorometric assay	50% inhibition	H Bonds and π interactions
Eriodictyol [209]	IC50: 3.91 mM	DPP-4 fluorometric assay	50% inhibition	Not available
Naringenin [207,209]	IC50: 5.5 mM; 0.24 ± 0.03 μM	DPP-4 fluorometric assay	50% inhibition	H Bonds and π interactions
Naringin [209]	IC50: 3.82 mM	DPP-4 fluorometric assay	50% inhibition	Not available
Hesperidin [209]	IC50: 5.7 mM	DPP-4 fluorometric assay	50% inhibition	H Bonds and π interactions
Hesperetin [207,209]	IC50: 5.7 mM; 0.28 ± 0.07 μM	DPP-4 fluorometric assay	50% inhibition	H Bonds and π interactions
Apigenin [207,210]	IC50: 0.14 ± 0.02 μM; 200 μM	DPP-IV GloTM Protease Assay	50% inhibition	H Bonds and π interactions
Quercetin [207]	IC50: 2.92 ± 0.68 μM	DPP-IV GloTM Protease Assay	50% inhibition	H Bonds and π interactions
Genistein [207]	IC50: 0.48 ± 0.04 μM	DPP-IV GloTM Protease Assay	50% inhibition	H Bonds and π interactions
Resveratrol [207,218]	IC50: 0.0006 ± 0.0004 μM	DPP-IV GloTM Protease Assay	50% inhibition	H Bonds
Gallic acid [207]	IC50: 4.65 ± 0.99 μM	DPP-IV GloTM Protease Assay	50% inhibition	H Bonds and π interactions