A study of the anti-bacterial activities of Nerium oleander's hydroalcoholic extract

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.