title: Angiotensin converting enzyme (ACE) inhibitory flavonoids from Erythroxylum laurifolium.
abstract: In our screening program for antihypertensive properties of plants in traditional use, the 99% ethanol extract of Erythroxylum laurifoiium leaves showed interesting angiotensin converting enzyme (ACE) inhibitory activity. The activity was found to be due to proanthocyanidins or condensed tannins and the flavonoids quercetin-3-O-rhamnoside (quercitrin) (IC(50) = 0.67 mM) and kaempferol-3-O-rhamnoside (afzelin) (IC(50) = 2.8 mM). In addition, quercitrin with afzelin demonstrated in vitro synergistic ACE inhibitory activity.
authors.affiliation: Department of Pharmacognosy, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Hansen
authors.forename: A
authors.initials: A
authors.lastname: Adsersen
authors.forename: U W
authors.initials: UW
authors.lastname: Smitt
authors.forename: U
authors.initials: U
authors.lastname: Nyman
authors.forename: S B
authors.initials: SB
authors.lastname: Christensen
authors.forename: C
authors.initials: C
authors.lastname: Schwartner
authors.forename: H
authors.initials: H
authors.lastname: Wagner