Snapshot
- Overview
- A fermentation-derived preservative that keeps formulas fresh.
- Category
- Preservative
- Type
- Preservative
Polylysine
Polylysine is a fermentation-derived, water-soluble cationic peptide made of repeating lysine units. In cosmetics it's used as a broad-spectrum preservative that keeps water-based formulas fresh and stable.
Like this ingredient?
Our take
Is Polylysine a Good Ingredient?
Good rating because it preserves water-based formulas effectively at low levels and is generally well tolerated, with stable performance across typical cosmetic pH. Its cationic peptide nature provides broad antimicrobial coverage with low irritation potential.
What it does
Skin Benefits
Guards products against microbial spoilage, supporting freshness over time. Works efficiently in high-water systems, maintaining product quality between uses.
Where you'll find it
Uses in Skincare & Cosmetics
Used in water-based serums, gels, and liquid moisturizers to bolster preservation. Also appears in toners and essences for freshness retention.
Before you use it
Safety
Generally low irritation, though its cationic character may cause mild stinging or redness in very sensitive skin at higher levels. Patch testing is prudent for reactive skin. No widely noted cosmetic regulatory restrictions.
Products with Polylysine
