فهرست مطالب somaye sabzali

Treatment of bacterial diseases by synthetic antibiotics leads to problems such as side effects in human and antibiotic resistance in microorganisms. Recently, plants have been given more attention in curing bacterial diseases. Since the use of Thymbra spicata is common in Iranian ancient medicine, this study tried to investigate the antibacterial effects of the extract of Thymbra speculate on some gram positive and gram negative pathogenic bacteria. The mentioned plant was collected from Zagros mountains, Ilam province, Iran. After naming and identification, the plant extract was provided by the maceration method. The bacteria were affected by different concentrations of the extract using the disc diffusion method. Diagnostic antibiotics were used as positive control and DMSO as negative control. MIC and MBC were also determined. The highest effect of the extract was found in gram positive bacteria. The maximum zones of inhibition were observed in 76 mg/ml concentration of the extract, and S. aureus and S. epidermidis were more sensitive than other bacteria (P˂0.05). The lowest MIC was pertaining to S. aureus (1885) with 2.5 mg/ml and S. epidermidis (2405) with 5mg/ml of extract. E. coli and K. penemonia with 15 mm zone of inhibition were the most sensitive gram negative bacteria to the extract. The hydroalcoholic extract of T. spicata had a considerable antibacterial effect. Statistic assessment of the inhibition zones showed that the extract was more effective on gram positive bacteria

Nerium oleander is used to cure several diseases in China and the Arabs، ancient medicine. This study tried to investigate the anti-bacterial activities of the hydroalcoholic extract of Nerium oleander which is native of Ilam province.

Nerium oleander was collected from the Zagros mountains، Ilam province، Iran. After naming and identification، the plant extract was provided by the maceration method. The Pothogenic bacteria were effected by different concentrations of the extract using the disc diffusion method. Diagnostic antibiotics were used as positive control. MIC and MBC were also determined.

The maximum effect of Nerium oleander’s hydroalcoholic extract was found in the concentration of 76 mg/ml. The maximum zone of inhibition in 76 mg/ml concentration was related to E. faecalis 2321 bacterum، and the minimum zone of inhibition was related to P. aeruginosa in the same concentration. In determining MIC and MBC، it was found that S. aureus1885 had the lowest MIC in 5 mg/ml concentration، and E. coli and P. aeruginosa showed the highest MIC in 76 mg/ml concentration.

The results showed that positive gram bacteria were more sensitive to Nerium oleander extract than negative gram bacteria. According to the bacteria’s zones of inhibition، it can be concluded that hydroalchohalic extract of Nerium oleander has a considerable anti-bacterial effect on the bacteria under the investigation.