Quorum sensing (QS), a complex biochemical communication mechanism utilized by bacteria, plays a pivotal role in orchestrating the transcription and expression of genes involved in crucial pathogenic activities such as biofilm formation and virulence. Biofilms are microbial communities encased in a self-produced matrix, which helps bacteria adhere to surfaces and resist immune defenses. This study aims to investigate the QS ability of Enterococcus faecalis, a gram-positive bacterium predominantly found in the gastrointestinal tracts of humans, by exploring the intricate interplay between the exposure of bacterial samples to selected solfeggio frequencies (396 Hz, 432 Hz, 528 Hz, 741 Hz, and 963 Hz) and the resulting differences in biofilm thickness. The biofilm formation (BF) in each sample has been evaluated through the crystal violet staining method along with spectrophotometric analysis. The results obtained from this research revealed noteworthy variations in the patterns of biofilm formation, intriguingly influenced by the different solfeggio frequencies applied. Specifically, the groups subjected to the distinctive frequencies of 432 Hz, 741 Hz, and 963 Hz demonstrated a notable reduction in biofilm thickness, suggesting a discernible attenuation in the quorum sensing of the Enterococcus faecalis strain. These findings provide experimental evidence that specific solfeggio frequencies (SF) possess the capacity to modulate quorum sensing, thus presenting a highly promising avenue for manipulating bacterial behavior and offering potential therapeutic interventions to combat the formidable challenges posed by biofilm-related infections
