1-acetyl-4-(hydroxylphenyl) piperazine inhibits biofilm formation in ESKAPE pathogens Klebsiella pneumoniae and Acinetobacter baumannii

The emergence of multidrug-resistant bacterial strains such as Klebsiella pneumoniae, Acinetobacter baumannii, and methicillin-resistant Staphylococcus aureus, known for their recalcitrant biofilm-forming abilities, poses significant challenges to current antimicrobial therapies. This study evaluates the efficacy of 1-acetyl-4-(4-hydroxyphenyl) piperazine in inhibiting the growth and biofilm formation of these high-priority pathogens, as well as assessing its potential cytotoxicity in mammalian cell lines. The compound demonstrated minimum inhibitory concentration at 1 mg/ml against Klebsiella pneumoniae subsp. rhinoscleromatis (MTCC-661) strain, Klebsiella pneumoniae, Acinetobacter baumannii clinical isolates and 0.5 mg/ml against methicillin-resistant Staphylococcus aureus (ATCC-MRSA-NR-46071). Molecular docking revealed strong interactions with key biofilm-associated proteins, including YcgR and BlrP1 in Klebsiella pneumoniae, and CarO, Omp38, CsuA/B, and BfmR in Acinetobacter baumannii, with binding energies ranging from −6.0 to −7.2 kcal/mol, indicating mechanisms that potentially disrupt biofilm formation. Up to 34% of biofilm reduction was observed at twice the minimum inhibitory concentration among the pathogens, demonstrating dose-dependent inhibition. Additionally, the compound was tested for cytotoxicity in the NIH 3T3 Mouse Fibroblast cell lines, with 93% cell survival at 10 mg/ml concentration. These findings suggest that AHPP is a promising candidate for further development into therapeutic agents or coatings designed to combat biofilm-associated infections, offering potent antimicrobial and biofilm inhibitory activities with minimal cytotoxicity.