Prebiotic/Probiotic/Postbiotic

Bacillus … Ferment Extract

INCI: BACILLUS/FOLIC ACID/SOYBEAN FERMENT EXTRACT

Reviewed by Daisy · Last updated 14 Aug 2026

A fermented plant extract that conditions and supports skin barrier function

Best For Skin Types

All, Dry, Sensitive, Mature

Addresses

Dryness, Hydration, Barrier repair

Usage Frequency

Daily

What Is Bacillus … Ferment Extract?

Bacillus/Folic Acid/Soybean Ferment Extract is a complex ingredient derived from fermented soybean. The fermentation process, carried out using Bacillus bacteria, breaks down soybean proteins and other compounds into smaller, more bioavailable molecules. This creates a nutrient-rich extract that contains amino acids, peptides, and B vitamins (including folic acid), alongside the metabolic byproducts of fermentation.

In skincare formulations, this ingredient functions primarily as a skin conditioner, helping to improve hydration and support the skin's structural integrity. The fermentation process is believed to enhance the ingredient's efficacy compared to non-fermented soybean extracts, though the precise mechanisms are still being explored.

How It Works

The fermentation process breaks soybean components into smaller peptides and amino acids that can be more readily absorbed by the skin. These molecules work to condition the skin by filling in gaps in the stratum corneum (outer layer), reducing transepidermal water loss and improving hydration.

The folic acid and other B vitamins present in the extract may also support normal skin cell turnover and metabolic function, though the concentration of these vitamins in typical skincare products is usually modest.

Clinical Evidence & References

Published research specifically on this multi-component ferment extract is limited. Most evidence comes from studies on soybean extracts or fermented plant extracts more broadly, which suggest benefits for skin hydration and barrier support. The fermentation process is thought to enhance bioavailability, but direct comparative studies are sparse.

The ingredient is well-established in cosmetic use and generally recognised as safe, though individual clinical efficacy data for this specific formulation would strengthen confidence in its benefits. Current evidence supports its use as a conditioning agent, though dramatic transformative effects should not be expected.

How to Use

This ingredient is typically used as part of a complete skincare routine and does not require special application instructions. It is commonly found in serums, essences, moisturisers, and treatment products. Use as directed on the product packaging, typically once or twice daily as part of your regular regime.

Safety & Precautions

Generally well-tolerated across most skin types. Those with soybean sensitivity should check the full ingredient list and perform a patch test first, though fermentation may reduce allergenic potential.

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