Evaluation of antibacterial activity of three Iranian medicinal plants

Abstract

Medicinal plants are the oldest known source for treatment of disease. Using pharmaceutical plants and plant extracts have been at great attention. In this research, the antibacterial activity of the methanolic and aqueous extracts of three Iranian medicinal plant species namely Capparis spinosa L., Adiantum capillus-veneris L. and Sambucus ebulus L. were tested against six bacteria strains including (Staphylococcus aureus , Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa ). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for each plant were determined by microdilution method. The maximum antimicrobial activity of aqueous extracts was exhibited by S. ebulus . The methanolic extract of S. ebulus had the best MIC values against S. epidermidis, S . aureus , B. subtilis and K. pneumonia (25, 50, 100 and 100 mg/ml, respectively) and the methanolic extract of A. capillus-veneris had the best MIC value against S. aureus and S. epidermidis (12.5 and 50 mg/ml) and the methanolic extract of C. spinosa had the best MIC value against E. coli (100 mg/ml). Key words: Sambucus ebulus , Adiantum capillus-veneris, Capparis spinosa, Antibacterial effects, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). INTRODUCTION The use of medicinal plants as a source for relief from illness can be traced back over five millennia to written documents of the early civilization in Iran, India and China. In recent years, multiple drug resistance in human has been developed due to indiscriminate use of commercial antibacterial drugs commonly used in the treatment of infectious diseases. This situation has forced scientists to search new antibacterial agents in various sources like medicinal plants (Kumar et al., 2006). Plants are used medicinally in different countries and are a source of many potent and powerful drugs (Jeyachardran et al., 2010). Adiantum capillus-veneris L and Sambucus ebulus L. grow in the northern regions of Iran especially in the