Determining the MIC and Comparative Efficacy of Gentamicin and Kanamycin Against E. coli

Abstract Antibiotic resistance poses a significant threat to global public health, with Escherichia coli (E. coli) being one of the most prevalent antibiotic-resistant bacteria. The aim of this study was to determine the minimum inhibitory concentrations (MICs) of kanamycin and gentamicin on E. coli, and to compare their effectiveness at different concentrations. A disc diffusion method was employed under standardized laboratory conditions using four increasing concentrations of each antibiotic, and then areas of inhibition zones were measured. The results showed that both antibiotics exhibited MICs between 6–30 µg/mL, with no statistically significant difference in their inhibitory effectiveness (p > 0.05). These findings indicate that both antibiotics are comparably effective against the E. coli strain tested within this concentration range. This suggests potential interchangeability depending on clinical and situational needs. Determining accurate MIC values is essential for selecting appropriate dosages that minimize the risk of resistance development. Ultimately, this contributes to more effective treatment strategies and helps mitigate the broader impact of antimicrobial resistance in pathogenic bacteria like E. coli.