active
Astaxanthin
The salmon-pink carotenoid from Haematococcus pluvialis microalgae — orders of magnitude more potent ROS quenching than vitamin E and beta-carotene in vitro. Algenist (the original biotech-algae brand) and a wave of 2024–2025 longevity-clean lines (Symbiome, BeautyStat) carry topical astaxanthin as the anti-photoaging hero antioxidant. Microalgae-fermented sourcing is the clean credential.
Benefits
- exceptional antioxidant capacity (singlet oxygen quenching)
- photo-aging defense and post-UV recovery support
- characteristic pink color doubles as natural pigmenting in tinted products
Example uses
- Algenist Genius Liquid Collagen
- longevity AOX serums
- post-UV recovery treatments
Mechanism of action
A xanthophyll carotenoid with a conjugated double-bond system spanning the molecule, plus two hydroxylated ionone rings — the structure that quenches singlet oxygen approximately 6,000× more efficiently than vitamin C and 550× more than vitamin E in standardised in-vitro assays. Lipid-soluble; integrates into cell membranes spanning both leaflets, protecting both the polar and apolar regions from peroxidation. Modulates Nrf2 antioxidant response signalling and downregulates UVA-induced MMP-1.
Clinical evidence · Moderate
Solid in-vitro antioxidant chemistry; several oral-supplementation RCTs on skin elasticity and crow's-feet; topical RCTs are smaller (n=20–50) but consistently positive on photodamage markers.
Effective concentration range
0.01–0.1% (color-saturated above this)
Formulation notes
Effective at 0.01–0.1% in serums; light- and oxygen-sensitive — encapsulation or opaque packaging required. Pairs with vitamin E for AOX recycling and lipid-phase stability.
Watchouts
Color-staining at higher doses. Stability is the open formulation challenge.
Controversies & overclaims
The 6,000× vitamin C number is a single in-vitro singlet-oxygen assay endlessly recycled in marketing — total antioxidant capacity in physiological systems is much closer to other carotenoids and tocopherols. Microalgae sourcing (Haematococcus from photobioreactors) is generally well-controlled; wild-harvest claims are usually fictional.
Market positioning
Sold as 'the strongest antioxidant ever discovered' — a chemistry-class claim with limited skin-clinical translation. Real value is as one strong leg of a stacked antioxidant system, not a stand-alone hero.
Comedogenicity
0 / 5
Sensitisation risk
Low
INCI & aliases
Haematococcus Pluvialis Extract
haematococcus pluvialis extract · microalgae astaxanthin
Clean beauty perception
Strongly positive, biotech-clean and microalgae sourcing aligned.
Related ingredients
Graph relationships
Timeline