Investigating the antimicrobial activity of different extracts of neem plant on antibiotic resistant Escherichia coli

Neem (Azadirachta indica) is known as a medicinal plant due to its antibacterial, antimalarial, antiviral and antifungal properties. The aim of this study is to investigate the antimicrobial activity of neem medicinal plant prepared with different solvents on antibiotic resistant Escherichia coli.Neem medicinal plant leaves were collected from Sistan and Baluchistan region, extracted in dry shade and using different solvents, and minimum inhibitory concentration and minimum lethal concentration were determined by microdilution method.The results of this study showed that the lowest inhibitory concentration of ethanol extract of neem against Escherichia coli was 2.5 mg/ml, and 2 strains were inhibited at this concentration, while the highest inhibitory concentration was 10 mg/ml and 4 strains were inhibited in this concentration.The lowest inhibitory concentration of neem acetone extract is 0.62 mg/ml, and one strain is inhibited at this concentration, and the highest inhibitory concentration is 5 mg/ml, and 5 strains are inhibited at this concentration. While the lowest and highest inhibitory concentrations against Escherichia coli were 1.25 and 10 mg/ml, and 1 and 3 strains were inhibited at this concentration.The lowest inhibitory concentration of neem acetone extract is 0.62 mg/ml, and one strain is inhibited at this concentration, and the highest inhibitory concentration is 5 mg/ml, and 5 strains are inhibited at this concentrationThe results showed that neem extract had a good inhibitory effect on Escherichia coli at low dilutions.