In-vitro antibacterial effects of Artemisia extracts on clinical strains of P. aeruginosa, S. pyogenes, and oral bacteria

Background and objective: Some common problems in the health care system are Microbial resistance to antibiotics, the side effects of food additives, and preservatives. Considering the antibiotic resistance of microorganisms and the need to identify new compounds, the present study was conducted to determine the antimicrobial effects of Artemisia extracts. Material an‎d Method The study was performed in two stages including extraction and determination of antibacterial properties of aqueous, ethanolic, methanolic, acetone/ethanolic, and hydroethanolic extracts of Artemisia on standard Pseudomonas aeruginosa, Streptococcus pyogenes, and oral bacteria sample. The well diffusion method was performed to evaluate the concentration that had an inhibitory and bactericidal effect. Result: Aqueous extract had an effect on the oral bacteria sample (8 mm), the methanolic extract had an effect on S. pyogenes and oral bacteria sample (15 mm) and finally acetone/ethanolic extracts had antimicrobial properties against S. pyogenes (16 mm). The concentration used for all five extracts was 50 mg/ml and showed an inhibition effect on the growth of S. pyogenes standard strain and oral bacteria sample. The less serial dilutions of extracts were tested but no antibacterial effects were seen. So, 50 mg/ml was the minimum concentration that had an inhibitory and bactericidal effect. Conclusion: It can be inferred that aqueous, methanolic, and acetone/ethanolic extracts of Artemisia had the highest inhibitory effect on S. pyogenes and the oral bacteria sample. Consequently, by applying different extraction methods and by utilizing different solvents, it may be possible to more efficiently obtain biomaterials with antimicrobial properties from this plant.