Subtilisin is an enzyme, a serine-protease (protein-degrading enzyme where serine is in the active site) obtained by microbial fermentation. This enzyme is characterized by a very wide substrate specificity and good stability to pH and temperature, so it can catalyze the cleavage of most peptide bonds in a protein, including keratin, reducing it to small peptides that are easily soluble.
Therefore, it can be applied to the skin to carry out a keratolytic action; thus, Subtilisin is an excellent natural substitute for hydroxy acids AHAs, BHAs, and PHAs. Furthermore, comparative tests for keratolytic effect showed that the bacterial proteolytic enzyme is effective, with a mild, non-irritating action, while AHAs have a higher irritating potential. It dissolves the "glue" that holds keratinocytes on the skin surface, eliminating dull, pigmented, or dead cells, revealing a refreshed, bright, and glowing appearance without irritation or sensitization.
In addition, it can break down peptides produced in hair follicles, which are building blocks for keratin, a primary protein component of hair. So, Subtilisin limits hair growth in undesirable areas, revealing fresher, younger, and flawless skin.
Subtilisin breaks down keratin until free amino acids that act as NMFs (natural moisturizing factors), providing secondary beneficial effects, improving skin hydration, and lessening transdermal moisture loss. Compared with chemical peeling, enzymatic peeling is a more natural form of exfoliation, with no inferior efficacy and better safety, and is gaining popularity in high-end skin care applications.
