What Is Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate?
Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate is a naturally derived ingredient created through fermentation. It starts with two plant materials: soybeans (Glycine max) prized for their protein and lipid content, and the roots of Lithospermum erythrorhizon, a purple gromwell plant traditionally valued in Asia for its soothing red pigments called shikonins. These botanicals are placed in a controlled environment with a friendly microorganism from the Bacillus family. As the Bacillus bacteria break down the plant material, they release smaller molecules, peptides and antioxidants that are easier for skin and hair to take in. The liquid that is strained off after fermentation is the filtrate used in cosmetics.
Plant ferment ingredients gained popularity in Korean beauty labs looking for gentle yet potent alternatives to synthetic additives. Over time formulators worldwide discovered that the combination of soybean nutrients, shikonin compounds and Bacillus-derived enzymes offers a balanced mix of moisture and protection, making the filtrate a versatile asset in skincare and haircare.
Production involves soaking and sterilizing the soybeans and gromwell roots, inoculating them with a selected Bacillus strain, then letting the mixture ferment at warm temperatures until the desired bioactive profile is reached. The batch is filtered to remove solids and further refined for clarity and safety before it is added to cosmetic bases.
You will most often spot this ferment in hydrating sheet masks, lightweight anti-aging serums, calming moisturizers, scalp treatments and leave-in hair conditioners where a plant sourced antioxidant boost is desired.
Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate’s Cosmetic Benefits/Uses
This multitasking ferment supports both skin and hair in several ways
- Antioxidant – helps neutralize free radicals generated by UV light and pollution which can otherwise speed up visible aging and dullness
- Hair conditioning – smooths the cuticle so strands feel softer look shinier and become easier to detangle
- Skin conditioning – supplies amino acids and sugars that reinforce the skin barrier improve elasticity and leave a comfortable finish
- Emollient – adds a light layer of moisture that reduces roughness without feeling greasy making formulas suitable for most skin types
Who Can Use Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate
This ferment is generally well tolerated by all skin types, including dry, normal, combination and oily. Its light emollient nature offers moisture without heaviness so even acne-prone users tend to find it comfortable. Sensitive skin usually benefits from the soothing properties of shikonin compounds, though those with a known allergy to soy should be cautious because trace proteins may remain from the soybean portion of the ferment.
The ingredient is derived entirely from plant sources and the Bacillus microorganism, so it meets vegan and vegetarian standards. No animal ingredients or by-products are involved in its production.
Current safety data does not flag any specific issues for pregnant or breastfeeding women when the ferment is used topically and in the low percentages found in cosmetics. This is not medical advice, and anyone who is expecting or nursing should have a quick word with a qualified healthcare professional before adding new products to their routine.
The filtrate does not heighten sensitivity to sunlight, so users do not need to take special photoprotection measures beyond the daily SPF that dermatologists already recommend.
Because the ingredient is water soluble and lightweight it plays nicely with most other common actives such as niacinamide, hyaluronic acid and gentle exfoliating acids. It is also stable across the typical cosmetic pH range so formulators can combine it without concern for major performance drop-off.
Potential Side Effects/Adverse Reactions
Reactions to topical Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate differ from person to person. The issues listed below are uncommon and most users will never experience them when the ingredient is properly formulated and used as directed.
- Allergic response in individuals with soy sensitivity
- Mild redness or stinging during first uses as skin adjusts
- Contact dermatitis if paired with very strong exfoliants or retinoids in the same routine
- Rare staining of light fabrics due to the natural red-violet pigment from gromwell roots
Discontinue use and seek professional guidance if any persistent irritation or other unexpected reaction occurs.
Comedogenic Rating
Rating: 1 / 5
The filtrate is largely water based with minimal residual oils so it does not have the thick occlusive texture that normally blocks pores. While soybeans contain some fatty components fermentation reduces their size and quantity which keeps the overall product light. For that reason it earns a low score of 1 rather than a perfect 0, reflecting a very small but not zero chance of clogging in extremely sensitive or congestion-prone skin.
Most people who break out easily should find this ingredient compatible with their routine.
The only situation that might tip the scale is if the ferment appears in a formula loaded with heavier butters or waxes because comedogenicity depends on the entire product not just one component.
Summary
Bacillus/Lithospermum Erythrorhizon Root/Soybean Ferment Filtrate acts as an antioxidant, skin and hair conditioner and light emollient. During fermentation Bacillus enzymes break down soy proteins and shikonin-rich gromwell root to create small peptides sugars and protective compounds that soak easily into skin and hair, reinforcing the barrier, smoothing strands and helping neutralize free radical damage.
The ingredient has gained moderate popularity in Korean inspired skincare and niche clean beauty lines but has yet to become a household name worldwide. Formulators appreciate its plant origin and gentle performance which is pushing it into more serums masks and leave-in conditioners each year.
Topical safety data is strong with only rare reports of irritation or soy-related allergy. As with any new cosmetic step it is smart to patch test a product containing this ferment before full application so you can be sure it suits your personal skin needs.