Hydrogen peroxide (H₂O₂) is a powerful oxidising agent that exhibits broad-spectrum antimicrobial activity against viruses, bacteria, yeasts, fungi, and bacterial spores. Its effectiveness stems from its ability to generate reactive oxygen species (ROS), such as hydroxyl radicals (•OH), which damage cellular components of pathogens.
Mechanism of Action
- Oxidative Damage – Hydrogen peroxide disrupts microbial cell membranes, proteins, and DNA by oxidation, leading to cell dysfunction and death.
- Free Radical Production – When H₂O₂ decomposes, it releases hydroxyl radicals that aggressively attack lipids, proteins, and nucleic acids.
- Disruption of Enzymatic Systems – Many microbes rely on enzymes for survival, and hydrogen peroxide inactivates key enzymes, impairing their metabolic functions.
- Spore Germination Inhibition – Bacterial spores have tough protective coats, but hydrogen peroxide penetrates and disrupts their dormancy, preventing germination.
Efficacy Against Various Microorganism
- Bacteria & Bacterial Spores – H₂O₂ kills both Gram-positive and Gram-negative bacteria, including resistant strains like Staphylococcus aureus (MRSA) and Clostridium difficile spores.
- Viruses – It inactivates both enveloped and non-enveloped viruses by damaging their protein coats and genetic material.
- Fungi & Yeasts – It disrupts fungal cell walls and metabolic processes, making it effective against species like Candida and Aspergillus.