Abstract

Artemisia absinthium (Asteraceae) is widely used in Iranian traditional medicine. Its effects may be correlated with the presence of antioxidant compounds. Methanolic extract of A. absinthium aerial part at flowering stage was screened for antioxidant activities by five complementary test systems. Also, its antidepressant activity was determined by forced swimming (FST) and tail suspension tests (TST). The extract showed good antioxidant activity. Also, the extract showed good reducing power activity between 50 and 800 µgml^-1. The extract exhibited a good activity in H₂O₂scavenging (IC₅₀ = 243 ± 12.15 µg ml^-1). IC₅₀ for iron ion chelating activity was 419 ± 20.95 µg ml^-1. Quercetin, BHA, EDTA and ascorbic acid used as positive controls in parallel experiments. The extract showed high phenolic and flavonoid contents. Extract showed good antidepressant activity in FST. The extract shortened remarkably the immobility period during the FST and TST and exhibited a dose dependent activity. All test groups were significantly different form control group (P < 0.001). Extract at 500 mg kg^-1 showed similar activity as imipramine 10 mg kg^-1(p > 0.05) in TST. LD₅₀ was 3700 mg/kg. These results introduced A. absinthiumaerial parts as an easily accessible and edible source of natural antioxidants and antidepressant.

Key words: Antidepressant, Antioxidant activity, Artemisia absinthium, DPPH, forced swimming test, tail suspension test.