Antimicrobial Activity of Lepidium drabaExtract on some Pathogenic Microorganisms“in vitro

In recent years, due to the common use of commercial antimicrobial drugs in the treatment of infectious diseases, the resistance to one or more antibiotics is increasing. The use of Lepidium drabaas an herbal plant in Iran, has a long history. The aim of this study was to evaluate the anti-microbial activity of Lepidium drabaextract on some of microorganisms causing infection (in vitro).

In this experimental study, the extract of Lepidium drabaaimed by maceration method. Extraction efficiency was calculated based on dry weight. The antimicrobial effect of the Lepidium drabaextract was studied by evaluated minimum inhibitory concentration, minimum bactericidal/fungicidal concentration, and determination of the zone of microbial growth inhibition (disc diffusion agar and well diffusion agar) on Escherichia coli, Salmonella typhi, listeria innocua, Staphylococcus epidermidis and Candida albicans.

The minimum inhibitory concentration and the minimum fungicidal concentration of aqueous extract of Lepidium drabawere 64 and 128 mg/ml for Candida albicans (the most sensitive strain to extract), respectively. The minimum inhibitory concentration of extract for Escherichia coli, Salmonella typhi, Listeria innocua, and Staphylococcus epidermidis was 256, 256, 128 and 128 mg/ml, respectively. The minimum bactericidal concentrations of the extract of Lepidium drabafor these strains were 256,256, 128, and 256 mg/ml, respectively. For all infectious strains, analysis of data at 5% significance level showed that, by increasing the concentration of the extract, the diameter of zone of microbial growth inhibition (disk diffusion agar and well agar diffusion) had increased. The results showed that the diameter of zone of microbial growth inhibition in the well agar diffusion method was higher than the disk agar diffusion method.

The extract of the Lepidium drabahad antimicrobial effecton all strains. The most susceptible and resistant to this extract were candida albicans and Escherichia coli, respectively. It is recommended that further studies be conducted in vitro and animal model to use this plant for treating infectious diseases and control the growth of pathogenic microorganisms