Effects of different phenological stages on chemical profile, antioxidant, antibacterial, and anti-inflammatory activities of Artemisia absinthium L. root and aerial parts extracts

Due to the importance of rangeland medicinal plants, the present study was conducted to assess the chemical profile and antioxidant, antibacterial, and anti-inflammatory activities of rangeland-medicinal plant Artemisia absinthium L. root and aerial parts extracts at different phenological stages (vegetative, flowering, and seeding). Folin-Ciocalteu and aluminum chloride colorimetric methods were used for determination of total phenol and flavonoids contents, respectively. The ethanol extract biological activities were investigated at different phenological stages: the antioxidant activity by DPPH free radical scavenging activity and ferric reducing antioxidant power (FRAP) methods; the antibacterial activity by disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods; and the anti-inflammatory activity using human red blood cell stabilization. The results showed that the highest amount of total phenol (86.4 ± 2 mg gallic acid equivalents (GAE)/g dry weight) and total flavonoids (36.2 ± 1.3 mg quercetin equivalents (QE)/g dry weight) was recorded for the root at flowering stage. Also, the root extract at flowering stage had the highest antioxidant (IC50 = 15.4 μg.mL-1) and antibacterial activities. The largest inhibition zone (22 mm) was observed for this extract against Staphylococcus aureus. This extract MIC and MBC were recorded 18.7 mg.mL-1 and 37.5 mg.mL-1 against S. aureus and Bacillus cereus, respectively. The bacteria Vibrio cholerae and Escherichia coli showed less sensitivity to the mentioned extract. Also, the results showed that the flowering stage had the highest anti-inflammatory activity compared to the other phenological stages. The root extract at the all phenological stages showed higher anti-inflammatory activity than the aerial parts. Overall, it could be concluded that A. absinthium, particularly at flowering stage, can be considered as a suitable alternative source for synthetic antioxidants, antibiotics, and anti-inflammatory agents.