Skin Whitening and Brightening Extracts for Glycerin Soap

For adding to glycerin soap to achieve skin whitening and brightening effects, consider water-soluble extracts that are stable and effective in a soap base environment. While the contact time in soap is short (wash-off product), certain ingredients can still offer benefits.

Here are some suitable options based on their properties and solubility:

• Tranexamic Acid (Trans-White™): This is a water-soluble ingredient known for reducing melanin formation and is suitable for addressing blemishes and overall skin brightening. It has a relatively wide pH stability range (3-8), which can be compatible with some soap bases.
• CosmoWhite™ (1-Methylhydantoin-2-Imide): A water-soluble powder shown to be effective in reducing skin pigmentation.
• Z-White™: This water-soluble ingredient works through unique mechanisms to inhibit tyrosinase formation and can enhance the effects of other whitening agents.
• Licorice Extract (Glabridin 4.5%, Water-Soluble): A water-soluble extract known for both whitening and anti-irritation properties. It should be added at lower temperatures to maintain efficacy.
• AEPWhite™ (Aminoethylphosphinic Acid, Skin Whitening Stabilizer): A highly stable, water-soluble ingredient that works by stabilizing DOPAchrome, a step in melanin production. It offers good tolerance and can be added at temperatures below 60°C.
• Hexylresorcinol AF (e.q. Hentowhite): This is a water-soluble form of Hexylresorcinol, effective for reducing dark spots and whitening. It works at multiple stages of melanin production and is non-irritating.

Important Considerations for Soap:

• Wash-off Product: Keep in mind that soap is a wash-off product, so the contact time with the skin is brief. The whitening effect may be less pronounced compared to leave-on products like creams or serums.
• pH and Temperature: Soap bases typically have a high pH. While some ingredients listed are stable in a wider pH range, others may be sensitive. Also, many extracts are sensitive to heat, so they should ideally be added to the melted soap base at the lowest possible temperature before pouring.

Always check the specific usage instructions and recommended concentration for each ingredient to ensure proper incorporation and effectiveness in your soap formulation.