In vitro enhancement of ciprofloxacin, tobramycin, and nystatin activity by irradiated aqueous garlic extract against multidrug-resistant pathogens causing otitis media

Abstract

Otitis media (OM) is a worldwide major health and economic issue leading to hearing loss, especially in developing countries due to high antibiotic resistance among the causative pathogens. This study aimed to isolate, purify and determine the prevalence of MDR microorganisms causing OM. Additionally, estimate in vitro effectiveness of irradiated and un-irradiated aqueous garlic extract (AGE). Finally, evaluate the enhancement of CIP, TOB, and NYS, commonly used in OM treatment, with IAGE against identified MDR bacteria and fungi. Herein, the in vitro data revealed that, OM is more prevalent in middle aged adults than in children. OM were predominated by bacterial isolates (59.0%), followed by fungal isolates (41.0%), including Pseudomonas aeruginosa (5 isolates), Proteus mirabilis (3 isolates), in addition to Klebsiella pneumoniae, Alcaligenes faecalis, Enterococcus faecalis, Bacillus cereus, Penicillium chrysogenum, Aspergillus flavus, and Aspergillus niger (1 isolate). Irradiated AGE (IAGE) showed nearly the same antimicrobial activity as un-irradiated AGE. The inhibition activity enhancement was more statistically significant (P< 0.001) on combination of IAGE with CIPNYS than with TOB (P< 0.05) and (P< 0.001) compared with each alone. Noticeable morphological changes in P. aeruginosa and A. flavus were observed by TEM images after the combination of IAGE with CIP/NYS. This study is one of primarily attempts to evaluate the IAGE to be used in future as a natural, safe, sterile, low coast, and available whole additive in therapeutic to overcome MDR problem.