Phenylalanine
Also known as: L-Phenylalanine (amino acid)
INCI: Phenylalanine | Function: Skin Conditioning | Type: Amino acid (essential)
What Is Phenylalanine?
Phenylalanine 是一种必需氨基酸 (essential amino acid), 是蛋白质合成的基础单元, 也是 tyrosine (酪氨酸) 和 melanin (黑色素) 生物合成的前体。在护肤品中作为皮肤调理剂, 帮助维持皮肤蛋白质结构和保湿功能。是 NMF (天然保湿因子) 氨基酸组成的一部分。
Key Skin Benefits
- + Essential amino acid — 蛋白质合成所需
- + Skin conditioning — 维持角质层水分结合能力
- + Part of NMF amino acid pool — 天然保湿因子成分
Pros
- + Natural component of skin — high biocompatibility
- + Part of NMF — supports skin barrier function
- + Generally well-tolerated and non-irritating
Cons
- − As melanin precursor — theoretical concern (unproven topically)
- − Must be avoided by PKU individuals in ingestible products
- − Limited standalone benefit — best in amino acid complexes
Specifications
| Property | Value |
|---|
| Usage Areas | Face, Eye, Body, Hair |
| Product Type | Leave-On, Rinse-Off |
| Source | Plant / Synthetic (fermentation) |
| Natural Level | Natural-derived |
Safety Ratings
| Metric | Rating |
|---|
| Skin Sensitivity | 0/5 |
| Comedogenic Rating | 0/5 |
| EWG Score | 1/10 |
Regional Regulatory Limits
| Region | Leave-on % | Rinse-off % | Status |
|---|
| EU (CosIng) | No limit | No limit | Allowed |
| US (CIR/FDA) | No limit | No limit | Allowed — GRAS |
| Japan (MHLW) | No limit | No limit | Allowed |
| ASEAN | No limit | No limit | Allowed |
| China (NMPA) | No limit | No limit | Allowed |
Typical Usage % by Product Type
| Product Type | Typical % |
|---|
| Anti-aging serum | 0.1–1% |
| Moisturizer (amino acid complex) | 0.1–0.5% |
| Hair treatment | 0.1–1% |
References
- EU CosIng Database. https://ec.europa.eu/growth/tools-databases/cosing/
- Rawlings AV et al. (2004) — NMF amino acids and skin hydration. PMID: 15059135
- PubChem — Phenylalanine. https://pubchem.ncbi.nlm.nih.gov/