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. 2014 Jan 16;16(2):258–268. doi: 10.1208/s12248-013-9549-4

Table I.

Inhibitory Effects of Various Dietary Flavonoids on Tolbutamide 4-Hydroxylation in Rat Liver Microsomes

Flavonoids Mean of selective inhibition of tolbutamide metabolism (%, n = 3) Natural source
1 μM 10 μM 100 μM
Ketoconazole (positive control) 45.9* 80.9** 100.0**
Flavones
 Wogonin 28.9* 51.4** 84.2** Herba Scutellaria baicalensis
 Apigenin 7.4 21.7* 76.9** Parsley and celery
 Chrysin 6.9 60.8* 75.3* Passion flower
 Luteolin 13.5 38.0* 93.5** Parsley and broccoli
 Capillarisin 19.4 34.9* 79.6** Herba Artemisiae scopariae
 Isovitexin 35.6* 37.5** 45.5** Barley grass juice, rice hull
 Cynaroside 9.4 −0.3 25.1* Parsley and celery
 Homoorientin 3.4 2.5 20.2 Herba Swertia japonica
 Baicalin −2.0 −5.4 7.8 Herba Scutellaria baicalensis
 Baicalein 6.5 1.8 5.1 Herba Scutellaria baicalensis
 Diosmin −7.1 4.7 2.5 Citrus
 Genkwanin 30.9* 37.4* 48.1** Aquilaria sinensis
Flavonols
 Tamarixetin 42.0* 88.3** 90.4** Herba Tamarix chinensis
 Isorhamnetin 18.7* 61.2** 87.7** Sea buckthorn
 Quercetin 15.1* 44.9** 92.1** Onion, cranberry
 Kaempferol 5.7 52.5* 73.1** Onion and Gingko biloba
 Fisetin 5.5 26.6 73.0* Strawberries and onion
 Myricetin −3.2 10.6 89.0** Onion and berries
 Isoquercitrin 21.0 27.1 62.0** Onion and berries
 Morin 14.3 11.5 51.1* Guava
 Quercitrin 24.2 21.1 13.5 Onion and berries
 Rutin −2.6 −4.0 −6.5 Buckwheat and berries
Flavanones
 Naringenin 4.4 51.3* 81.6** Grapefruit juice
 Eriodictyol 32.8 28.7* 69.8** Yerba santa
 Taxifolin −1.3 31.2* 50.6** Milk thistle
 Liquiritin 18.1 18.4 24.8 Licorice
 Poncirin −5.9 16.4 18.8 Citrus
 Naringin −11.5 −13.3 −24.3 Grapefruit juice
 Hesperetin −3.6 29.1 56.1* Citrus
 Hesperidin 11.9 2.6 6.7 Citrus
Isoflavones
 Genistein 49.7* 67.8** 82.8** Soya beans
 Formononetin 23.4 30.6* 62.0* Herba Radix astragali
 Puerarin 38.2 39.1* 33.4 Herba Radix puerariae
 Daidzein 1.4 13.5 24.6* Soya beans
 Daidzin 1.0 −2.5 −1.2 Soya beans
Chalcones
 Phloretin 23.8 34.5 95.4** Apple
 Isoliquiritigenin 0.9 29.7 95.7** Licorice
Catechins
 (−)-Epicatechin 1.1 −8.6 5.5 Green tea and wine
 (+)-Catechin −3.1 −8.5 −0.2 Green tea and wine
 (+)-Epicatechin 17.0 6.3 −12.0 Green tea and wine

*p < 0.05; **p < 0.01 vs. control