An Experimental Study on the Potential of Honey Lactobacilli to Combat Multidrug-Resistant Acinetobacter baumannii (MDRAB) in Northern Iran

Backgrounds: Infections caused by Acinetobacter baumannii represent a global health threat in medical settings. This research aimed to investigate the phenotypic characteristics of antimicrobial resistance in A. baumannii strains isolated from post-burn infections as well as the antagonistic effects of honey probiotics on multidrug-resistant isolates.
Materials & Methods: A total of 220 post-burn wound samples were analyzed to identify A. baumannii strains using microbiological and molecular tests. The Kirby-Bauer test was conducted according to CLSI (Clinical and Laboratory Standards Institute)-2021 guidelines to determine resistance phenotypes. Additionally, probiotics were isolated from 11 honey types through phenotypic and molecular methods, and their antagonistic properties were evaluated using the disk diffusion method.
Findings: Out of the 63 A. baumannii isolates identified, 76.19% exhibited multidrug-resistance. Most of the isolates were obtained from patients with second-degree burns,  accounting for 23.81% of the cases. The highest antibiotic sensitivity was against amikacin, with a sensitivity rate of 58.73%. In the disk diffusion tests, the average growth inhibition zone diameter for all multidrug-resistant A. baumannii isolates was 29 mm when treated with Lactobacillus plantarum derived from Camelthorn honey. This probiotic effect was significantly 1.7 times greater than that of L. delbrueckii and 1.9 times greater than that of L. acidophilus.
Conclusion: Although this in vitro study did not investigate the biochemical properties of honey, certain native Iranian honeys were shown to possess desirable anti-Acinetobacter properties due to the presence of lactobacilli.