Comparing the production of carbon dots synthesized from Lactobacillus acidophilus and Bifidobacterium bifidum and investigating their antibacterial effects

Document Type : Original Research Article


1 Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran

2 Mycobacteriology and Pulmonary Research Department, Microbiology Research Center, Pasteur Institute of Iran

3 Department of Microbiology, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran



Objective(s): Klebsiella pneumoniae is a significant opportunistic bacterial pathogen, responsible for over 70% of human infections. The development of carbapenem resistance is considered a major risk to public health.
Methods: Cultivation of Klebsiella pneumonia isolates (100 samples) for phenotypic identification. Drug sensitivity was evaluated by disc diffusion method, and carbapenemase-producing isolates were identified by the mCIM and eCIM methods.  Lactobacillus acidophilus and Bifidobacterium bifidum were cultured and carbon dots were synthesized by hydrothermal method. The physicochemical properties of the carbon dots were investigated and their antibacterial activity against Klebsiella pneumonia isolates was determined.
Results: After identifying Klebsiella pneumonia isolates, 70 carbapenem-resistant isolates were found among the samples. Of these, 41% were serine carbapenemase and 29% were metallo-beta-lactamase. The minimum inhibitory concentration (MIC) for synthesized carbon dots was observed to be around 50 mg/mL.
Conclusions: Due to their beneficial properties, carbon dots can be used as an antimicrobial agent to treat antibiotic-resistant infectious diseases. This group of nanoparticles exhibits high activity and can be proposed as a new strategy to combat resistant infections.


Main Subjects

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