Derived from the fermentation of radish roots, this biotechnological ingredient serves as a natural antimicrobial agent. It provides broad-spectrum protection against bacteria and fungi while simultaneously offering mild skin-conditioning and hydrating properties.
- INCI Name:
- Leuconostoc/Radish Root Ferment Filtrate
- Chemical/Scientific Name:
- Leuconostoc/Raphanus Sativus Root Ferment Filtrate
- Common Aliases:
- Radish Root Ferment, Leucidal Liquid
| Category: | Preservatives |
| Source Origin: | Biotechnological (Fermentation of Raphanus sativus) |
| Comedogenic Rating: | 0 |
| Primary Industries: | Clean Beauty, Natural Skincare, Haircare |
| Solubility: | Water-soluble |
At a Glance: Properties & Effects
| Antimicrobial Efficacy: | |
| Hydration/Moisture: | |
| Formula Stability: | |
| Irritation Risk: |
- Primary Benefits: Natural preservation, skin barrier conditioning, humectant-like moisture retention, and scalp-soothing anti-dandruff activity.
- Potential Risks: Limited efficacy against certain robust molds in complex formulas; potential for reduced viscosity in specific gel-based systems.
Biological Action & Cosmetic Profile
Microbiological control is achieved through the production of antimicrobial peptides known as bacteriocins. During the fermentation of radish roots by the lactic acid bacterium Leuconostoc kimchii—the same species involved in traditional kimchi production—these peptides are secreted as secondary metabolites. These molecules feature a cationic (positively charged) structure that allows them to bind to the negatively charged cell membranes of pathogenic microorganisms. This binding causes physical disruption of the microbial membrane, leading to the leakage of intracellular components and subsequent cell death.
Conditioning benefits arise from the polysaccharides and peptide fragments remaining in the filtrate after the fermentation process is complete. These components act as humectants, mirroring the behavior of the skin’s Natural Moisturizing Factor (NMF) to draw moisture into the stratum corneum. Unlike synthetic preservatives like Phenoxyethanol, this ferment provides these functional benefits without the typical risk of stinging or sensitization, making it a preferred choice for compromised or sensitive skin barriers.
Formulation stability depends significantly on pH and temperature parameters. While the ingredient is active within a pH range of 3.0 to 8.0, its efficacy is often maximized in slightly acidic environments where microbial pressure is naturally lower. It is heat stable up to approximately 70°C, though many formulators prefer adding it during the cooling phase to ensure the integrity of the bioactive peptides remains intact.
Broader Applications & Origins
The transition toward “preservative-free” marketing has solidified this ingredient’s role in the cosmetic industry. Because it is categorized as a skin-conditioning ferment rather than a traditional preservative on various global regulatory annexes, brands can utilize its antimicrobial properties while maintaining a clean-label aesthetic. It is frequently paired with other natural hurdles to create a robust self-preserving system in products containing Aqua and Aloe Barbadensis Leaf Juice.
Routine Integration
- Synergies: Efficacy increases when combined with chelating agents like Gluconolactone or additional boosters such as Ethylhexylglycerin and Caprylyl Glycol. It works harmoniously with humectants like Glycerin and Sodium Hyaluronate to enhance skin softness.
- Conflicts: High concentrations may negatively impact the viscosity of formulas thickened with Carbomer. Care should be taken when using it as the sole preservative in formulations high in protein or complex botanical extracts, where Sodium Benzoate or Potassium Sorbate may be required for complete broad-spectrum coverage.
Clinical Consensus & Safety
The Expert Panel for Cosmetic Ingredient Safety (CIR) has evaluated radish root-derived ingredients and concluded they are safe for use in cosmetic practices at current concentrations, which typically range from 0.5% to 4.0%. Clinical studies published in peer-reviewed journals confirm that the filtrate is non-irritating and non-sensitizing to human skin. Furthermore, challenge testing according to USP and PCPC standards demonstrates that the ingredient effectively inhibits the growth of common contaminants including S. aureus, E. coli, and C. albicans, though its potency against certain molds can be variable depending on the total formulation environment.
Is this a “natural” preservative?
Yes, it is derived from vegetable fermentation and is ECOCERT/COSMOS approved. It serves as an alternative to synthetic parabens and formaldehyde donors.
Can it treat acne?
While it is not an FDA-approved acne treatment like Salicylic Acid, its antimicrobial properties may help inhibit the growth of bacteria that contribute to blemish formation.
Is it safe for fungal acne?
Most evidence suggests it is safe, as it possesses antifungal activity against Malassezia species, the yeast responsible for fungal acne (pityrosporum folliculitis).