OCTOPUS INK EXTRACT AS A POTENTIAL QUORUM-QUENCHING CANDIDATE FOR Staphylococcus aureus BIOFILM IN AQUACULTURE (REVIEW)

Abstract

Staphylococcus aureus is a Gram-positive opportunistic pathogen detected in seafood, cultured aquatic animals, aquaculture water, and fish-handling environments. Its persistence is supported by multiple virulence determinants and biofilm formation, which enhances tolerance to environmental stress, host defenses, disinfectants, and antimicrobial treatment. The accessory gene regulator (agr) quorum-sensing system coordinates density-dependent expression of several virulence-associated traits, making bacterial communication a potential antivirulence target. Octopus ink contains alkaloids, phenolic compounds, steroids, melanin-associated components, peptides, and other bioactive constituents with reported antimicrobial, antioxidant, and immunomodulatory activities. This review evaluated the potential of octopus ink extract to interfere with quorum sensing and biofilm development in S. aureus. A systematic literature review and content analysis were conducted using 67 scientific articles, primarily from Scopus-indexed Q1-Q4 journals published during 2017-2026. Importantly, evidence specifically supporting antibiofilm and quorum-sensing interference in S. aureus derives mainly from studies of alkaloids and related bioactive compounds, rather than from direct experimental testing of octopus ink extract against S. aureus. These studies indicate possible mechanisms involving reduced adhesion, interference with ica-associated matrix production, modulation of Agr signaling, membrane disruption, and metabolic inhibition. However, Agr inhibition does not consistently suppress biofilm formation because it may also reduce dispersal in some strains. Therefore, octopus ink extract should be regarded as a promising multi-target quorum-quenching and antibiofilm candidate, not a confirmed agent against S. aureus. Direct mechanistic studies are required to validate its efficacy and safety in aquaculture.