Antibacterial Activity of Ascorbic Acid (Vitamin C) Against Urinary Quinolones Resistant Coliform Species

Abstract

One hundred and ten clinical samples were collected from both gender who visited or admitted to AL- Salam General Teaching Hospital from patients suffering from urinary tract infections (UTIs). All samples were cultured on selective media as MacConkey and blood agar aerobically.

Coliform isolates are identified to species level depending on biochemical and physiological tests and using Rapid ™ ONE panel kit to be conformed to the diagnosis. The susceptibility of coliforms species to a variety of antibiotics has been investigated. The results showed the majority of them were resistant to most antibiotics. Coliforms species isolated from UTIs indicated high level of resistance to the fluoroquinolone agents,  resistance was observed most often to nalidixic acid followed by norfloxacin and ciprofloxacin. The minimum inhibitory concentration ( MIC ) values of ciprofloxacin against coliforms species ranged from 4-128 μg / ml. Ascorbic acid (Vitamin C) showed excellent antibacterial activity against urinary quinolones resistant species alone or in combination with antibiotics. The MIC of ascorbic acid was (5mg / ml) against all tested species. The sub-MIC of ascorbic acid (1mg / ml) showed synergistic effect with ciprofloxacin against urinary ciprofloxacin-resistant coliform spp..