Antibacterial activity of hydroalcoholic extract of Cardin leaf on Listeria monocytogenes, Salmonella enteritidis and Pseudomonas aeruginosa

In recent years, multiple drug resistance in human pathogenic microorganisms have developed due to indiscriminate use of commercial antimicrobial drugs commonly used in the treatment of infectious diseases. This situation forced scientists for searching new antimicrobial substances from various sources, like medicinal plants, which are the good sources of novel antimicrobial chemotherapeutic agents. In this study, the antibacterial effect of Cardin leaf was investigated. Hydroalcoholic extract of this plant was prepared at concentrations of 0.390 to 100 mg/ml and antimicrobial effect of extract were tested with disk diffusion and agar-well diffusion diffusion method against Listeria monocytogenes, Salmonella enteritidis and Pseudomonas aeruginosa strains. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the Cardin extract were investigated by dilution method. In the disk and well diffusion methods, the highest effect of extract on the bacteria was observed at concentration of 100 mg / ml, with the highest diameter of deterioration hole. Of course, the effect on gram-positive bacteria was more than gram negative. The inhibitory concentration of extract (MIC) on Listeria monocytogenes, Salmonella enteritidis and Pseudomonas aeruginosa was 12.5, 25 and 50 mg/ml and the MBC was 50, 100 and 100 mg/ml, respectively. The results showed that effect of Cardin extract on gram-positive bacteria was more than gram negative and the diameter of the non-growth halo increased with increasing concentrations of the extract.