Ascorbic acid inhibitory activity on resistant strains of Enterobacter spp.: in vitro study

  • Sara H Mohamed Department of Microbiology, National Organization for Drug Control and Research, Giza, Egypt
  • Yasmine M Saied Department of Microbiology, National Organization for Drug Control and Research, Giza, Egypt


Enterobacter species, members of Enterobacteriaceae family that belong to the ESKAPE group, were expressed as the principal rise of nosocomial resistant infections. This study was aimed to test the antibacterial activity of ascorbic acid on Enterobacterclinical strains. Four Enterobacter strains were collected and identified by both biochemical and MALDI-TOF methods. Antibiotic susceptibility testing of commercially available antibiotics was performed using disc diffusion method. Antibacterial activity of ascorbic acid was tested by using agar well diffusion and broth microdilution methods. The collected strains were identified as three strains Enterobacteraerogenes and one strain Enterobacter cloacae. High resistance rates toward both cefotaxime and nalidixic acid were obtained by disc diffusion method. By well diffusion, 100 mg/ml and 50 mg/ml concentrations of ascorbic acid were found to be effective. While by using microbroth dilution, concentrations of 1.5, 3.125 and 6.25 mg/ml of ascorbic acid were detected as minimum inhibitory concentrations. Our results demonstrated a good antibacterial activity of ascorbic acid on Enterobacter strains and further studies on ascorbic acid/antibiotics combinations are in need.

Keywords: Enterobacter aerogenes, Enterobacter cloacae, ascorbic acid, MALDI-TOF


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How to Cite
Sara H Mohamed, and Yasmine M Saied. “Ascorbic Acid Inhibitory Activity on Resistant Strains of Enterobacter spp.: In Vitro Study”. Current Research in Pharmaceutical Sciences, Vol. 9, no. 4, Jan. 2020, pp. 67-72, doi:10.24092/CRPS.2019.090403.
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