Exploring the Antimicrobial Potential of Hallachrome, a Defensive Anthraquinone from the Marine Worm Halla parthenopeia (Polychaeta)

• Published in: Marine drugs Vol. 22; no. 9; p. 380
• Main Authors: Ferri, Anita, Simonini, Roberto, Sabia, Carla, Iseppi, Ramona
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.09.2024; MDPI
• Subjects: Animals; Anthraquinone; Anthraquinones; Anthraquinones - chemistry; Anthraquinones - isolation & purification; Anthraquinones - pharmacology; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - isolation & purification; Anti-Bacterial Agents - pharmacology; Anti-Infective Agents - chemistry; Anti-Infective Agents - pharmacology; Antibiotics; Antiinfectives and antibacterials; Antimicrobial agents; Antimicrobial resistance; Aquatic Organisms; Bacteria; Biofilms; Biofilms - drug effects; Candida albicans; Candida albicans - drug effects; Chemical defense; Coliforms; Defense mechanisms; defensive; Drug resistance; Drug resistance in microorganisms; E coli; Fungi; Global health; Gram-negative bacteria; Gram-Negative Bacteria - drug effects; Gram-positive bacteria; Gram-Positive Bacteria - drug effects; Halla parthenopeia; Health aspects; Instrument industry; Marine chemistry; Marine invertebrates; Marine organisms; Membrane permeability; Microbial Sensitivity Tests; Mucus; Natural products; Nosocomial infections; Organisms; Pathogens; Permeability; Polychaeta; Public health; Staphylococcus epidermidis; Staphylococcus infections; Staphylococcus aureus; Staphylococcus epidermidis; Virulence; United States; Candida albicans; Staphylococcus aureus; anthraquinone; Escherichia coli; defensive; Enteroccocus faecalis; Pseudomonas aeruginosa; Staphylococcus epidermidis; mucus
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md22090380

Antimicrobial resistance is a critical global health issue, with rising resistance among bacteria and fungi. Marine organisms have emerged as promising, but underexplored, sources of new antimicrobial agents. Among them, marine polychaetes, such as , which possess chemical defenses, could attract significant research interest. This study explores the antimicrobial properties of hallachrome, a unique anthraquinone found in the purple mucus of , against Gram-negative bacteria ( ATCC 25922, ATCC 9027), Gram-positive bacteria ( ATCC 29212, ATCC 6538, ATCC 12228), and the most common human fungal pathogen ATCC 10231. Antibacterial susceptibility testing revealed that Gram-negative bacteria were not inhibited by hallachrome at concentrations ≤2 mM. However, Gram-positive bacteria showed significant growth inhibition at 0.12-0.25 mM, while was inhibited at 0.06 mM. Time-kill studies demonstrated dose-dependent growth inhibition of susceptible strains by hallachrome, which exerted its effect by altering the membrane permeability of , , and after 6 h and after 24 h. Additionally, hallachrome significantly reduced biofilm formation and mature biofilm in , , and . Additionally, it inhibited hyphal growth in . These findings highlight hallachrome's potential as a novel antimicrobial agent, deserving further exploration for clinical experimentation.