Science
Mechanism of Action
This ingredient is created by fermenting radish roots with Leuconostoc kimchii, a lactic acid bacterium. The fermentation yields an antimicrobial peptide that actively suppresses harmful microorganisms, thereby preserving the formulation and contributing to skin health. Its humectant properties attract and bind moisture, enhancing hydration and reinforcing the skin's natural barrier. Furthermore, it delivers antioxidant benefits through peptides, enzymes, and organic acids, defending against oxidative stress. The naturally occurring lactic acid offers mild exfoliating action, while its soothing capabilities help calm irritation, reduce redness, and stabilize skin pH, making it beneficial for even acne-prone skin by regulating microbial growth and inflammation.
Research
Clinical Evidence
High confidence2%
Key findings
- 01 Demonstrated efficacy against a broad spectrum of bacteria, including E. coli and A. niger, in preservative challenge testing.
- 02 Successfully prevented microbial proliferation in a cream base during rigorous challenge testing.
- 03 Recommended as a standalone natural preservative for comprehensive product protection.
- 04 Exhibited Minimum Inhibitory Concentration (MIC) against various microbes including A. brasiliensis, C. albicans, and S. aeruginosa.
- 05 Did not cause sensitization in a human repeated insult patch test (HRIPT) conducted on 50 subjects.
Transparency
Dusting Analysis
While very low concentrations (e.g., 0.03% in face/neck sprays) are reported in some products, these amounts are unlikely to provide significant active benefits like robust preservation or potent skin conditioning. For measurable antimicrobial effects, concentrations generally start at 0.25%, with 2-4% being optimal for standalone preservative action. Concentrations below 0.25% suggest potential dusting for active claims.
The Formula
Formulation
Stability
Highly stable, tolerating temperatures up to 60°C (140°F) and heat stable up to 70°C. Its antimicrobial peptides remain active within a wide pH range (pH 3-8), though activity decreases at pH 9. This water-soluble ingredient integrates easily into the water phase of formulations or can be added at the final stage, ideally below 50°C (120°F). It may subtly tint clear cosmetic products.
Conflicts
- When used as the sole preservative, additional fungal protection may be necessary for formulations highly susceptible to mold or yeast growth, as its efficacy against these specific microbes is comparatively weaker.
Safety
Safety Profile
The Cosmetic Ingredient Review (CIR) Expert Panel concluded it is safe for use in cosmetics, provided formulations are non-sensitizing. Human Repeated Insult Patch Tests (HRIPT) at 10% concentration showed no sensitization across 50 subjects. Phototoxicity studies indicated no photoirritation up to 3.7%, though higher concentrations (11%) reduced cell viability. Recognized as Generally Recognized As Safe (GRAS) by the FDA for food use, it exhibits low potential for allergenicity and minimal irritation, making it well-tolerated.
Your Skin
Skin Compatibility
Our Assessment
Verdict
Leuconostoc/Radish Root Ferment Filtrate is a valuable, naturally derived ingredient offering robust preservative capabilities alongside significant moisturizing, antioxidant, and soothing benefits for a wide range of skin types.
Related
Similar Ingredients
Finding similar ingredients…