Subtilisin

Subtilisin is a serine protease—an enzyme derived from Bacillus subtilis bacteria. In skincare, it functions as a keratolytic agent, meaning it breaks down proteins in the outermost layer of dead skin cells without requiring the acidity of chemical exfoliants like AHAs or BHAs.Unlike physical scrubs, subtilisin works through enzymatic action, making it a gentler option for exfoliation. It's classified as a skin conditioning agent in cosmetics because the process of removing dead skin can support a smoother skin texture and improve the appearance of the skin surface.

Subtilisin is a protease, which means it targets and breaks down protein structures. When applied to skin, it selectively cleaves dead keratin-rich cells on the stratum corneum (the outermost skin layer) without damaging living cells beneath. This protein-dissolving action is gentler than physical scrubbing and doesn't rely on the pH adjustment needed by chemical exfoliants.Because the mechanism is enzymatic rather than chemical, subtilisin exfoliation is often described as more neutral and less likely to disrupt skin pH or cause irritation in sensitive individuals, though individual tolera…

Enzymatic exfoliants like subtilisin are typically used 1-3 times per week, depending on skin sensitivity and the product formulation. Apply to clean, dry skin, leave for the time specified by the product (often 5-10 minutes), then rinse thoroughly with lukewarm water. Avoid mixing with acidic exfoliants (AHAs, BHAs) on the same day. Follow with hydrating and protective skincare, as exfoliation can temporarily increase sensitivity.

Subtilisin is generally well-tolerated in cosmetic formulations. However, as with any exfoliant, overuse may compromise the skin barrier. Those with active inflammation, open wounds, or severe sensitivity should patch-test first or consult a dermatologist.