What Is Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate?
Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate is a liquid ingredient that comes from fermenting Job’s tears seeds (Coix lacryma-jobi ma-yuen) and soybeans (Glycine max) with a friendly strain of Bacillus bacteria. During fermentation the bacteria break down proteins, sugars and lipids in the seeds into smaller bioactive parts such as peptides, amino acids and antioxidants. These smaller parts are easier for skin to take in and often more powerful than the raw plant material.
Job’s tears and soy have long histories in traditional foods and folk beauty practices across East Asia. Modern cosmetic labs picked up on these traditions in the early 2000s, experimenting with controlled fermentation to concentrate the skin-loving parts while removing heavy plant solids. Today the filtrate is made by soaking cleaned seeds in water, adding Bacillus, letting the mix ferment under controlled temperature and then filtering out the solids. The clear or slightly amber liquid that remains is the ferment filtrate used in skincare.
You’ll typically spot this ingredient in hydrating toners, soothing sheet masks, lightweight moisturizers, anti-aging serums, brightening essences and after-sun treatments. Formulators like it because it fits well in water-based systems and adds skin benefits without a heavy feel.
Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate’s Cosmetic Benefits/Uses
This multitasking ferment brings several perks to a formula:
- Antioxidant: The ferment is rich in natural compounds that help neutralize free radicals from UV light and pollution which can otherwise speed up visible aging
- Skin Conditioning: Its mix of peptides and sugars supports the skin’s barrier helping it feel smoother more elastic and better able to hold moisture
- Emollient: Light plant lipids left from the seeds soften rough spots and give skin a silky finish without clogging pores
Who Can Use Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate
This ferment filtrate is generally suitable for all skin types. Its water-light texture sits well on oily or acne-prone skin while the barrier-supporting peptides and lipids make it comforting for dry or sensitive complexions. Those with a known soy allergy should avoid it because residual soy proteins may be present.
The ingredient is plant derived and produced through bacterial fermentation so it fits vegan and vegetarian criteria with no animal sources used at any stage.
Current research shows no data suggesting harm for pregnant or breastfeeding users when the ingredient is applied topically. It does not contain vitamin A derivatives or hormonal actives. Still this is not medical advice and anyone who is pregnant or nursing should ask a physician before introducing new skincare.
The filtrate does not increase sun sensitivity so daytime use is fine alongside normal sunscreen habits.
Potential Side Effects/Adverse Reactions
Responses to topical Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate differ from person to person. The points below outline potential issues yet most people using a well-formulated product will not encounter them.
- Redness or stinging in very reactive skin
- Allergic contact dermatitis in individuals sensitive to soy or ferment by-products
- Rare acne flare if combined with highly occlusive products
- Irritation from contaminated or improperly preserved formulas
If any adverse reaction occurs stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1/5 – This ferment filtrate is mostly water based and contains only trace amounts of lightweight seed lipids so it is unlikely to clog pores. The few residual oils are minimal and remain dispersed in the water phase which keeps them from forming a heavy film. For these reasons the ingredient is generally considered safe for acne-prone skin. Formulas that pair it with thick occlusives could tip the scale but on its own it stays nearly non-comedogenic.
Summary
Bacillus/Coix Lacryma-Jobi Ma-Yuen Seed/Soybean Ferment Filtrate works as an antioxidant, skin conditioner and mild emollient. Fermentation breaks the seeds’ proteins and sugars into small peptides amino acids and polyphenols that soak in easily to fight free radicals strengthen the moisture barrier and leave skin soft. While not a headline ingredient like hyaluronic acid or niacinamide it shows up more often in modern Korean and Japanese formulas that focus on gentle hydration and barrier support.
Topical use is regarded as low risk with very few reported reactions aside from rare soy allergies. Still it is smart to patch test any new product to ensure your skin agrees with the full formula.