Get a Free 5ml Mini Now Free 5ml Mini With Every Order of The Mantle

BUTYLIDENEPHTHALIDE.

Questionable CAS 551-08-6 / PERFUMING

A naturally-occurring phthalide compound that demonstrates multi-pathway antioxidant activity through Nrf2 signaling and COX-2 inhibition. This celery-derived ingredient shows promise for skin brightening via tyrosinase inhibition, though formulation stability remains a significant challenge requiring oil-based systems.

antioxidant anti-inflammatory skin brightening fragrance masking

Science

Activates the Nrf2 antioxidant pathway while simultaneously inhibiting cyclooxygenase-2 (COX-2) and NF-κB/MAPK inflammatory cascades. Additionally suppresses tyrosinase enzyme activity to reduce melanogenesis and provide skin brightening effects.


Research

Medium confidence
Effective range 0.001–0.01%
Optimal

0.005%

Key findings

  1. 01 Human dermal fibroblast study at 10-100 μg/mL showed dose-dependent antioxidant activity with cytotoxicity above 100 μg/mL
  2. 02 Related compound study demonstrated 24% dermal absorption at 0.7% concentration in o/w cream formulation

Transparency

Commonly dusted
Min. effective
0.005%
Red flag below
0.01%

Often included at trace amounts primarily for fragrance masking rather than therapeutic benefit, with regulatory limits restricting meaningful active concentrations


The Formula

Solubility
Oil
Optimal pH 5 – 6.5
0 7 14

Stability

Extremely unstable in aqueous environments due to hydrolysis into ketoacids. Requires oil-based systems, nanoemulsions, or cyclodextrin encapsulation for stability.

Synergies

  • cyclodextrins
  • oil-soluble antioxidants
  • nanoemulsion systems

Conflicts

  • nitrosating agents
  • strong oxidizing agents
  • unprotected aqueous formulations

Safety

CIR Status
Not reviewed
Max tested
0.01%
Sensitization risk Moderate

Limited to 0.01% in some regions as fragrance component. GRAS status for food use but lacks comprehensive topical safety assessment.


Your Skin

Yes Normal
Yes Dry
Yes Oily
No Sensitive
Irritancy Moderate
Comedogenicity Unknown

Our Assessment

Questionable

Promising bioactivity is severely limited by formulation instability and restrictive concentration limits that prevent therapeutic efficacy.


Related

Finding similar ingredients…