What Is Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate?
Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate starts with the bark of the Machilus thunbergii tree, sometimes called Japanese bay. The bark is steam-distilled or cold-pressed to obtain a fragrant oil rich in phenolic compounds and fatty acids. This oil is then placed in a nutrient solution and inoculated with two friendly microbes: the yeast Kluyveromyces and the probiotic bacterium Lactobacillus. During a controlled, low-temperature fermentation the microbes break large molecules into smaller ones, release skin-loving peptides and create extra antioxidants. Once fermentation is complete the mixture is filtered to remove solids, leaving a clear, active-packed liquid known as a ferment filtrate.
Fermentation technology gained attention through traditional Asian beauty practices, where it was found to boost the potency and skin tolerance of plant ingredients. Cosmetic chemists adopted the method to produce lighter, faster-absorbing extracts for modern skincare. Today this particular filtrate is valued for offering the benefits of botanical oil without the heavy feel.
The ingredient appears most often in lightweight serums, anti-aging creams, soothing toners, hydrating sheet masks and spot-treatment ampoules. Formulators like it because it slips easily into water phases, adds minimal scent and plays well with both natural and synthetic actives.
Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate’s Cosmetic Benefits/Uses
This ferment filtrate earns its place on ingredient lists thanks to several skin-friendly roles:
- Antioxidant: Helps neutralize free radicals generated by pollution and UV light, which supports a brighter more even complexion and may slow the appearance of fine lines
- Astringent: Provides a gentle tightening effect that can make pores look smaller and leave skin feeling refreshed, especially useful in toners and light lotions for combination skin
- Skin Conditioning: Delivers fermented amino acids and sugars that boost moisture retention, giving formulas a soft, smooth after-feel without greasiness
- Skin Protecting: Forms a breathable barrier that helps shield the surface from environmental stressors and reduces transepidermal water loss, aiding overall skin resilience
Who Can Use Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate
This fermented filtrate is light, water based and non-greasy so it suits most skin types including oily, combination, normal and dehydrated dry skin. Its gentle astringent action may help balance excess sebum while the conditioning peptides and sugars support moisture for drier complexions. The ingredient is generally well tolerated by sensitive skin because the fermentation step lowers irritant compounds, though very reactive skin should still introduce any new product slowly.
Because it is sourced from plant bark and produced with microorganisms, not animal by-products, the filtrate is considered suitable for vegans and vegetarians. No part of the process relies on animal-derived enzymes or substrates.
Current data shows no specific risks for pregnant or breastfeeding women when the ingredient is used topically in cosmetic amounts. This is not medical advice and anyone who is expecting or nursing should run their full skincare routine past a qualified healthcare professional for personal guidance.
The filtrate is not known to cause photosensitivity, so it will not make skin more prone to sunburn. Standard daytime sun protection habits should still be followed whenever you use any skincare.
Potential Side Effects/Adverse Reactions
Reactions to topical Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate can vary from person to person. The following is a list of potential side effects that could occur, though they are uncommon when the ingredient is formulated and used correctly.
- Mild stinging or redness
- Itching or a tight sensation in very dry or compromised skin
- Allergic contact dermatitis in individuals sensitive to yeast or botanical extracts
- Temporary flushing if combined with strong exfoliants or alcohol-heavy formulas
- Rare breakout flare in those extremely prone to fungal acne due to the presence of yeast fragments
If you notice persistent irritation or any of the reactions listed above, discontinue use and consult a healthcare professional for advice.
Comedogenic Rating
Rating: 1 / 5
This filtrate is mostly water soluble and contains only trace amounts of the original bark oil’s fatty acids. Fermentation further breaks down heavier lipids, so what remains is a light liquid rich in amino acids, sugars and antioxidants that do not clog pores. Because of this the ingredient is generally considered safe for acne-prone skin and unlikely to trigger new breakouts.
Keep in mind that an end product’s overall pore-clogging potential also depends on other ingredients and the formula’s texture, so always judge the full ingredient list rather than this single component.
Summary
Kluyveromyces/Lactobacillus/Machilus Thunbergii Bark Oil Ferment Filtrate acts as an antioxidant, a gentle astringent, a skin conditioner and a light protective agent. Fermentation creates smaller molecules and extra bioactive peptides that mop up free radicals, lightly tighten pores, bind moisture and form a breathable shield against environmental stress.
While still a niche extract, it is gaining traction in Korean and indie formulations thanks to its lightweight feel and multitasking benefits. Large mainstream brands have yet to adopt it widely, so you will mostly see it in specialty serums, toners and sheet masks.
Existing research and user reports show a low risk of irritation or sensitisation, making the filtrate a safe choice for most skin types. That said, everyone’s skin is unique so it is wise to patch test any new product that features this ingredient before applying it to your whole face.