Full Length Research Paper

Comparison of the antioxidant activity and total phenolic contents in some Stachys species

Mahnaz Khanavi¹, Mannan Hajimahmoodi²*, Mina Cheraghi-Niroomand², Zahra Kargar², Yousef Ajani³, Abbas Hadjiakhoondi¹, Mohammad R. Oveisi²

¹Department of Pharmacognosy and Medicinal Plants Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box: 14155-6451, Tehran, Iran.

²Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box: 14155-6451, Tehran, Iran.

³Department of Pharmacognosy, Institue of Meicinal Plants, ACECR, P.O. Box: 13145-1446, Tehran, Iran.

*Corresponding author. E-mail: hajimah@sina.tums.ac.ir. Fax/Tel: +98 21 66954706.

Accepted 27 January, 2009

The methanolic extracts of the aerial parts of nine Stachys species: S. persica Gmel., S. fruticulosa M. B., S. laxa Boiss. & Buhse., S. inflata Benth., S. turcomanica Trautv., S. subaphylla Rech. F., S. setifera C. A. Mey., S. byzantina C. Koch and S. trinervis Aitch. & Hemsl. were investigated for their antioxidant activity and total phenolic content using FRAP and Folin-Ciocalteu assays respectively. S. persica Gmel. and S. fruticulosa M. B. had the highest antioxidant activity (61.42 and 62.02 mmol FeII/100g) and total phenolic content (3294.96 and 4450.36 mg gallic acid/100 g) among these nine species. There was a direct correlation between total phenol and antioxidant activity (R² = 0.9446, p ≤ 0.001) which indicates that polyphenols are the main antioxidants.

Key words: Stachys, antioxidant, total phenol.