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@article{208086,
        author = {Abhisri Banerjee},
        title = {Evaluating the Antibacterial Potency of Erythromycin Against Escherichia coli: Minimum Inhibitory Concentration and Zone of Inhibition Analysis},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {4},
        pages = {343-352},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=208086},
        abstract = {Antimicrobial susceptibility testing is essential for evaluating the effectiveness of antibiotics against bacterial pathogens. The present study investigated the in vitro antibacterial activity of erythromycin against Escherichia coli, a Gram-negative bacterium, using broth dilution and agar well diffusion assays. A laboratory strain of E. coli was cultured and characterized based on its colony morphology and Gram-staining properties. Erythromycin susceptibility was evaluated at concentrations of 2.5, 5, 10, and 20 mg/mL. In the broth dilution assay, visible bacterial growth was observed at 2.5 and 5 mg/mL, whereas no visible turbidity was observed at 10 and 20 mg/mL. Accordingly, the minimum inhibitory concentration (MIC) was determined as 10 mg/mL, representing the lowest concentration that completely inhibited visible growth. Agar well diffusion analysis further demonstrated inhibitory activity of erythromycin against E. coli, as evidenced by zones of inhibition surrounding the antibiotic-containing wells. The findings demonstrate that erythromycin possesses measurable in vitro antibacterial activity against the tested E. coli strain; however, the relatively high concentration required for growth inhibition suggests limited susceptibility under the experimental conditions. These findings highlight the importance of quantitative susceptibility assessment when evaluating antibiotic activity against Gram-negative bacteria.},
        keywords = {Escherichia coli, erythromycin, antimicrobial susceptibility, minimum inhibitory concentration, agar well diffusion, zone of inhibition.},
        month = {September},
        }