Antibacterial Effects of Camellia sinensis and Achillea millefolium on Several Antibiotic-resistant Bacteria

Abstract

Background and Objectives: Infectious diseases are among the most known important causes of morbidity and mortality in the world. The ongoing explosion antibiotic-resistant bacteria and side effects of medications, application of assistive methods including the use of medicinal plants for treatment have become particularly important. Materials and Methods: In this study, the ethanol extract of green tea (Camellia sinensis) and yarrow flower (Achillea millefolium) were prepared by maceration method and its antibacterial effect on four clinical strains of antibiotic resistant bacteria including Klebsiella pneumoniae, Acinetobacter, Escherichia coli and Pseudomonas aeruginosa were evaluated with microtiter plate method for determining the MIC (Minimum Inhibitory Concentration). Results: The MICs of green tea extract for Acinetobacter baumannii was 15.6 mg/ml and 31.25 mg/ml for Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli. The MIC of Achillea millefolium extract for Acinetobacter baumannii and Escherichia coli was 125 mg/ml and against Klebsiella pneumoniae and Pseudomonas aeruginosa was 250 mg/ml. Conclusion: Considering the antimicrobial effects of green tea and Achillea on four strains of resistant bacteria, the extract of this plant can be used in control and treatment of infections caused by these infectious agents.