Brightening agent (fungal-derived)
Kojic Acid
INCI: Kojic Acid·Studied at 1–2% (cosmetic)·Limited evidence
A compound produced by certain fungi, used in brightening formulas for the appearance of dark spots and a more even tone. It oxidises and browns readily in air and light, so packaging and freshness matter.
Studied for
- ·The appearance of an even tone
- ·The look of reduced dark spots and post-blemish marks
How it’s thought to work
Studied for the appearance of less visible uneven pigment through tyrosinase-related pathways; most supporting work uses it as one part of a brightening blend rather than on its own.
Questions
- Why does my kojic acid serum turn brown?
- Kojic acid oxidises in air and light, and a browning formula is that reaction showing. It does not necessarily mean the product is unsafe, but potency drops as it darkens, so opaque packaging and using it fresh matter.