Study of Chemical Compounds and The Antimicrobial Effects of Leaf Extract of Laurus nobilis L on Various Microbial Strains

The antibiotic resistance has provided the ground for substituting the herbal therapeutic methods with less side effects than the customary drugs. This research was also done in order to study the chemical compounds and antimicrobial effects of methanol extract of Laurus nobilis leaf in the densities of 100 ppm, 200 ppm, 400 ppm and 800ppm on a number of different microbial strains including Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Bacillus cereus and Aspergillus niger mold by disc dissemination method. The results showed that the methanol extract of Laurus nobilis leaf prevented from the growth of Staphylococcus aureus, Listeria monocytogenes and Escherichia coli bacteria, in a manner that the antibacterial effect of extract with increase of the extract density was also increased. while, it had no effect on Bacillus cereus and Aspergillus niger mold in the used densities. By comparing the antibiotics such as Chloramphenicol (in the density of 30μg/disc), Ampicillin (in the density of 10μg/disc), Gentamicin (in the density of 10μg/disc) and Kanamycin (in the density of 30μg/disc) as the positive standard with laurus nobilis leaf extract, it was specified that the effect of these antibiotics is more than the densities used of mentioned extract and in the meantime, the most and least effects were related to the Chloramphenicol and Ampicillin respectively. finally, it can be inferred that with regard to the gained results, Laurus nobilis leaf extract including antimicrobial materials has had antibacterial effects; but, it has less antifungoid effect.