Luteolin , a Flavone , Does Not Suppress Through an Inhibition of a - Glucosidase Jsa Postprandial Glucose Absorption

ty.i・2) The retardation of membrane-bound AGH reaction3} andlor inhibition of passive glucose transport`) would successfully flatten the postprandial blood glucose excursions or reduce hyperglycemia. In our studies on AGH inhibition by food components,5,6) acylated anthocyanins were found to cause the benefit of suppression of glucose production from dietary carbohydrates. To date, many studies on the antioxidant,') antimutagenic,8) and antihypertensive effects9} of fiavonoids have been done. In addition, their alternative physiological function of suppression of glucose absorption at the small intestine has been also reported."ie) Among the flavonoids, tea polyphenols such as catechins have been found to inhibit AGH activity2) and glucose transport.`) These findings led us to make a further investigation of fiavonoids cornmonly present in plant and food products for any anti-hyperglycemic effect. In this paper, we have examined the in vitro and in vivo AGH inhibition abilities of naturally occurring flavonoids, i.e., luteolin and chrysin as flavones, kaempherol and galangin as fiavonols.