Pamela Hindieh

Bacterial biofilms pose significant challenges in clinical, industrial, and environmental settings due to their inherent resistance to antimicrobial agents and host immune responses. Encased within a self-produced extracellular polymeric substance (EPS) matrix, these structured microbial communities demonstrate exceptional resilience, resisting conventional antimicrobial treatments and adapting to, as well as recovering from, environmental and therapeutic stresses, necessitating the development of novel anti-biofilm strategies. This review provides a comprehensive synthesis of biofilm formation, resistance mechanisms, and current and emerging approaches for controlling biofilms, with a primary focus on advancements made over the last decade. Chemical, physical, and biological strategies, including enzymatic degradation, natural compounds, chelating agents, nanoparticles, photodynamic therapy, and probiotics, have demonstrated promising antibiofilm activity. Additionally, combination therapies and targeted drug delivery systems have emerged as viable solutions to enhance the eradication of biofilms. Despite these advancements, challenges such as cytotoxicity, bacterial adaptation, and clinical applicability remain. Addressing these hurdles requires interdisciplinary research to refine existing strategies and develop innovative solutions for effective biofilm management.

The emergence, persistence, and spread of antibiotic-resistant microbes is a tremendous public health threat that is considered nowadays a critical One Health issue. In Lebanon, the consumption of raw bovine milk has been recently reported as a result of the financial crisis. The objectives of the current study were (1) to evaluate raw bovine milk samples in a comprehensive manner for the types of antibiotics used and their residues, (2) to determine the presence of mesophilic bacteria, extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA), and (3) to determine the associated human health risk caused by drinking raw milk with antibiotic residues among all age categories. LC-MS-MS was used to carry out the analysis. From 200 milk samples, 30 (15%) were found contaminated with four major antibiotics. The highest average concentration detected was for oxytetracyline 31.51 ± 13.23 μg/kg, followed by 5.5 ± 0.55 μg/kg for gentamicin, 4.56 ± 0.73 μg/kg for colistin, and 4.44 ± 0.89 μg/kg for tylosin. The mean contamination among most samples was below the maximum residue limits (MRLs). Upon comparison with the acceptable daily intake (ADI), the estimated daily intake (EDI) across all age groups was acceptable. The hazard quotient (HQ) was also below 1 across all age groups, signifying the absence of associated health risks for the Lebanese consumers. On the other hand, all milk samples were found exceeding the maximum tolerable value of mesophilic flora. Antibiotic-resistant bacteria (ARB) were detected and represented by ESBL-producing E. coli and MRSA isolates. Thus, the greatest threat of antibiotic use in Lebanon does not fall under antibiotic residues but rather the proliferation of antibiotic resistance in potentially pathogenic bacteria. In this study, the virulence profile of detected bacteria was not investigated; thus their pathogenicity remains unknown. Therefore, to mitigate this health threat in Lebanon, a “One Health” action plan against ABR is required. It will provide a framework for continued, more extensive action to reduce the emergence and spread of ABR in Lebanon.