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Updated: Feb 25, 2026

Quantification of Violacein in Chromobacterium violaceum and Its Inhibition by Bioactive Compounds
Published on: August 8, 2025
Violacein antimicrobial activity on Staphylococcus epidermidis and synergistic effect on commercially available
H V Dodou1, A H de Morais Batista1, G W P Sales1
1Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil.
Aims:
The study aimed to assess whether violacein has antimicrobial activity on Staphylococcus epidermidis and synergistically modulates the action of commercially available antimicrobial drugs.
Methods And Results:
Violacein showed excellent antimicrobial activity on biofilm-forming and nonbiofilm-forming S. epidermidis strains (ATCC 35984) (ATCC 12228), with bacteriostatic (MIC = 20 μg ml-1 and 10 μg ml-1 respectively) and bactericidal effects (MBC = 20 μg ml-1 for both strains), observed in short periods of exposure. The violacein bactericidal concentration led to S. epidermidis death after 2-3 h of exposure. Additionally, violacein synergistically modulated the activity of different antimicrobial classes on S. epidermidis ATCC 12228 (81·8%; n = 9) and on S. epidermidis ATCC 35984 (54·5%; n = 6), reducing the MIC of these antibiotics by up to 16-fold.
Conclusion:
Violacein shows excellent antimicrobial activity on S. epidermidis strains.
Significance And Impact Of The Study:
Violacein shows the potential for the development of a new drug for the treatment of infections caused by S. epidermidis.
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