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Ingredient · INCI reference

Phaeodactylum Tricornutum Extract

An extract of the marine diatom Phaeodactylum tricornutum used in skincare and sunscreens as a conditioning and antioxidant-type ingredient.

What it is

Phaeodactylum Tricornutum Extract is derived from a single-celled marine microalga (a diatom) cultivated in controlled conditions. It contributes carotenoids, polysaccharides, and other algal metabolites that are used in formulations for skin-conditioning and antioxidant support. In sunscreens it typically appears at low levels as part of a botanical or marine-themed supporting blend rather than as a structural or UV-active component.

Safety & warnings

Generally well tolerated as used in cosmetics. As with other botanical and marine extracts, sensitization is possible in predisposed individuals, and the composition can vary with the extraction method and solvent carrier.

Origin & sourcing

Natural in origin, obtained from cultivated marine diatom biomass that is harvested and extracted; the alga is commonly grown in photobioreactors to standardize the material.

Questions everyone asks

What is Phaeodactylum tricornutum?

It is a marine diatom, a type of single-celled microalga, whose extract is used in cosmetics for conditioning and antioxidant support.

Is it a sunscreen filter?

No. It is a conditioning and antioxidant-type extract used as a supporting ingredient, not a UV filter that absorbs or scatters ultraviolet light.

Sources & references

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