Planta Med 2008; 74(15): 1769-1773
DOI: 10.1055/s-0028-1088322
Original Paper
© Georg Thieme Verlag KG Stuttgart · New York

Anxiolytic Activity of a Phytochemically Characterized Passiflora incarnata Extract is Mediated via the GABAergic System

Oliver Grundmann1 , Jie Wang1 , Gerard P. McGregor2 , Veronika Butterweck1
  • 1College of Pharmacy, Department of Pharmaceutics, University of Florida, FL, U.S.A.
  • 2Pascoe Pharmazeutische Praeparate GmbH, Giessen, Germany
Further Information

Publication History

Received: May 15, 2008 Revised: August 26, 2008

Accepted: September 1, 2008

Publication Date:
12 November 2008 (online)


The purpose of this research was to assess the anxiolytic properties of a phytochemically characterized commercial extract from Passiflora incarnata (PI; Passifloraceae) in the elevated plus maze test in mice. Using an HPLC method, the flavonoids homoorientin, orientin, vitexin, and isovitexin were identified as major compounds. Following oral administration, the extract exerted an anxiolytic effect that was comparable to diazepam (1.5 mg/kg) at a dose of 375 mg/kg and exhibited a U-shaped dose-response curve. In addition, antagonism studies using the GABAA/benzodiazepine receptor antagonist flumazenil and the 5-HT1A-receptor antagonist WAY-100 635 were conducted. The active dose was effectively antagonized by flumazenil, but not by WAY-100 635. This study is the first demonstration of the in vivo, GABA-mediated anxiolytic activity of an HPLC- characterized extract of Passiflora incarnata.


Dr. Veronika Butterweck

College of Pharmacy

Department of Pharmaceutics

University of Florida

PO Box 100494


FL 32610


Phone: +1-352-273-7859