1. What is the Antimicrobial Efficacy of Vegetal Chitosan?

Vegetal chitosan is highly effective against a wide range of bacteria, fungi, and viruses, making it an excellent antimicrobial agent for textile applications. Its antimicrobial properties come from its positively charged amino groups, which interact with negatively charged microbial cell membranes, leading to:

✅ Cell membrane disruption, causing leakage of intracellular components.
✅ Inhibition of nutrient absorption, preventing microbial growth.
✅ Suppression of biofilm formation, reducing pathogen colonization on fabric surfaces​.

Vegetal chitosan is particularly effective against:

• Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis).
• Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa).
• Fungi and molds, including those responsible for odor formation in textiles.

2. How Does This Treatment Pass AATCC 100? What Is the Kill Rate of Pathogens?

The AATCC 100 test method is the standard antimicrobial assessment for textiles, measuring bacterial reduction after contact with treated fabric.

✅ Kill Rate: Vegetal chitosan-treated textiles typically achieve a ≥99% bacterial reduction (log 2-3 reduction) within 24 hours under AATCC 100 testing conditions​.
✅ Test Procedure:

• Chitosan-treated textile samples are inoculated with bacteria.
• Incubated at 37°C for 24 hours.
• Reduction in colony-forming units (CFUs) is compared to untreated control fabrics.
• A reduction of 99% or more indicates strong antimicrobial efficacy.

Lab studies on chitosan-treated fabrics have consistently demonstrated compliance with AATCC 100 standards, confirming its ability to maintain a high kill rate against pathogens​.

3. How Is the Efficacy After Multiple Washes?

The durability of vegetal chitosan’s antimicrobial effect depends on the application method and washing conditions:

✅ Durable Finishing Process: If covalently bonded or crosslinked with fiber, the antimicrobial effect can last for 30+ washes while maintaining >90% efficacy.
✅ Physical Coating Method: If applied as a surface treatment, efficacy may gradually decrease but remains effective up to 10–15 washes, depending on detergent type and washing temperature.
✅ Optimized for Long-Term Use: Chitosan formulations can be modified with nano-coatings or microcapsules to extend antimicrobial effects after repeated washing​.