Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate: What Is It, Cosmetic Uses, Benefits & Side Effects

Curious about this ingredient? In this article we're explaining exactly what it is and why it's used within cosmetic formulations.
Updated on: June 23, 2025
Share:
Inside this article:

All information on this page is verified using publicly available nomenclature standards and reference materials from The Personal Care Products Council (PCPC) and the European Commission's CosIng database. Our analyses are based on technical data from these sources to ensure accuracy and reliability.

What Is Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate?

Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate is a fermented blend made from rapeseed (Brassica napus) that has been processed with a friendly Bacillus bacterium in the presence of vegetable-derived glycerin. Rapeseed provides proteins, amino acids and lipids that the bacteria break down during fermentation, creating smaller, skin-friendly molecules and naturally produced peptides. Glycerin keeps the mixture hydrated throughout the process and ends up boosting the final product’s moisture-binding ability.

Fermentation as a beauty technique took off in Korean skincare, where scientists noticed that fermented plant extracts could deliver nutrients in a gentler more bioavailable form. This specific ferment showed promising results in lab tests for softening and protecting the skin, so formulators began adding it to moisturizers and treatment products in the late 2010s.

To make the ingredient, harvested rapeseed is cleaned and milled into a slurry, combined with water and glycerin then inoculated with a selected Bacillus strain. The mixture ferments in controlled tanks for several days before being filtered, concentrated and preserved for cosmetic use. The finished filtrate is a light, water-based liquid that blends seamlessly into most emulsions and gels.

You’ll most often spot this ferment in hydrating serums, daily moisturizers, soothing masks, barrier-support creams and anti-aging formulas where a gentle conditioning agent is needed.

Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate’s Cosmetic Benefits/Uses

This multitasking ferment supports skin in two main ways

  • Skin conditioning: Smooths and softens the surface, leaving skin feeling supple and refreshed while helping maintain balanced hydration thanks to the natural humectant power of glycerin and the amino acids released during fermentation
  • Skin protecting: Strengthens the skin’s barrier by supplying lipids and peptides that reinforce the outer layer, which can reduce moisture loss and help shield against everyday environmental stress

Who Can Use Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate

This ferment is generally well tolerated by all skin types including oily, combination, normal and dry. Its lightweight water-based nature means it will not feel heavy on oily skin while the humectant glycerin helps bind water for drier complexions. Sensitive skin usually fares well too because the ingredient contains no added fragrance or harsh acids; however extremely reactive skin should still choose formulas free of other potential irritants.

The raw materials come from plants and a harmless soil-derived bacterium, so the ingredient itself is suitable for vegetarians and vegans. No animal derivatives or animal testing are involved in its standard production.

Current safety data shows no specific risks for pregnant or breastfeeding women when this ferment is used in rinse-off or leave-on products at the typical low concentrations found in cosmetics. That said this is not medical advice and anyone who is expecting or nursing should always discuss new skincare products with a qualified healthcare provider first to be safe.

The filtrate does not increase photosensitivity, so there is no special need for additional sun protection beyond the daily SPF already recommended for everyone. It also layers well with common actives like niacinamide or hyaluronic acid without known conflicts.

Potential Side Effects/Adverse Reactions

Reactions to topical Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate differ from person to person. The points below list potential side effects only and they remain uncommon when the ingredient is properly formulated and used as directed.

  • Irritation – a small number of users may feel temporary redness stinging or warmth especially if their skin barrier is already compromised
  • Allergic contact dermatitis – very rare cases of itching or rash could occur in individuals allergic to rapeseed components or fermentation by-products
  • Breakouts – while non greasy any new product can occasionally trigger clogged pores in acne-prone skin if mixed with heavy occlusives
  • Interaction with other actives – products high in strong exfoliating acids or retinoids may amplify mild tingling though this is usually minimal

If any persistent burning swelling or rash develops discontinue use and consult a medical professional.

Comedogenic Rating

Rating: 1/5 – the filtrate is water based and contains only trace lipids from rapeseed after fermentation so it is very unlikely to clog pores. Glycerin is a known non-comedogenic humectant and the Bacillus fermentation process breaks larger molecules into lighter skin compatible fragments that rinse or absorb easily.

Suitable for acne-prone or breakout-prone skin in most cases.

As with any formula the overall pore-clogging risk depends on the other ingredients in the finished product so check the full ingredient list if you are highly sensitive.

Summary

Bacillus/Brassica Napus Extract/Glycerin Ferment Filtrate acts as a skin conditioner and protector. Fermentation unlocks small peptides amino acids and lightweight lipids that soften the surface while glycerin attracts and binds water helping reinforce the moisture barrier. These combined effects leave skin feeling smooth hydrated and more resilient against daily stress.

Although not a household name the ferment has gained steady traction in Korean inspired skincare and is now appearing in global serums creams and masks that focus on barrier care.

Current research and practical use suggest it is a very safe ingredient with low irritation and comedogenic potential. As with any new product though it is wise to perform a quick patch test before full-face use just to be cautious.

Was this article helpful?
More from Glooshi:
ADVERTISEMENT
Get all our top headlines in beauty.
Delivered right to your inbox each week. Zero spam, all goodness, opt-out at anytime.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Get the latest beauty news, top product recommendations & brand-exclusive discount codes direct to your inbox.
Send good feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Send bad feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Search