Comparative Study of Antibacterial Effects of Polar, Semi-polar and non-polar Fractions of Lnula helenium Plant Extract against some food-borne bacteria

Today, chemical drugs are replaced by herbal medicines because of the harmful effects they place on the human body. Although the proportion of herbal medicines to chemical drugs in the world is negligible, the replacement process is followed more quickly. The aim of this study was to investigate the antibacterial effect of polar, semi-polar and non-polar fractions of Lnula helenium extract on some food-borne bacteria . In this study, Lnula helenium plant was collected from Arak natural areas and then extracts of methanolic, chloroform and hexane of Lnula helenium were obtained. The effect of different concentrations of this extract was investigated. All experiments were carried out using Agar well diffusion and determination of MIC and MBC on standard strains of Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Streptococcus mutans. Methanol extract of Lnula helenium(6.25 μg / ml) inhibits the growth of Gram-positive and Gram-negative bacteria. Chloroform extract with minimum concentrations (12.5 mg / ml, 50 and 100%) had lethal effect on Streptococcus mutans, Staphylococcus aureus and Listeria monocytogenes, respectively and hexane extract only affected gram-positive bacteria. The herbal extract can be used as an herbal medicine after completing clinical trials.