Galactomyces/Olive Leaf Ferment Extract: 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 27, 2025
Share:
Inside this article:

We verify all information on this page using publicly available nomenclature standards from The Personal Care Products Council (PCPC), the European Commission's CosIng database and documentation provided directly by ingredient manufacturers. Our analysis is based on technical data from these sources to ensure accuracy and reliability.

What Is Galactomyces/Olive Leaf Ferment Extract?

Galactomyces/Olive Leaf Ferment Extract is a skin care ingredient created by fermenting olive tree leaves (Olea europaea) with a yeast called Galactomyces. Olive leaves bring antioxidants, polyphenols and natural sugars while the yeast breaks these components down into smaller, more skin friendly molecules. The fermentation process also produces amino acids, vitamins and organic acids that help soften and condition skin.

The blend of olives and fermentation grew out of the beauty trend that looked to sake breweries, where workers’ hands appeared unusually smooth due to constant contact with fermented ingredients. Brands began experimenting with different plant materials and discovered that olive leaves pair well with Galactomyces, leading to this extract’s debut in Korean and Japanese skin care about a decade ago. Manufacturers steep dried olive leaves in a nutrient solution, introduce the yeast culture, allow it to ferment under controlled temperature and then filter the liquid to create a clear, lightweight extract ready for cosmetic use.

You will most often spot Galactomyces/Olive Leaf Ferment Extract in lightweight essences, hydrating toners, sheet masks, moisturizers, anti aging serums and soothing after-sun gels where a smooth, non greasy finish is needed.

Galactomyces/Olive Leaf Ferment Extract’s Cosmetic Benefits/Uses

This ingredient plays a single but important role in skin care formulations.

As an emollient it coats the skin surface with a thin, breathable layer that helps fill in rough spots and soften texture. This boosts immediate smoothness, improves the slip and spreadability of a product and supports a comfortable, hydrated feel without heaviness.

Who Can Use Galactomyces/Olive Leaf Ferment Extract

This fermented olive leaf extract is lightweight and non greasy so it suits most skin types, from dry to oily and even combination or mature skin. Because it mainly sits on the surface as a softening film it rarely clogs pores or triggers excess oil. Sensitive skin usually tolerates it well, though anyone prone to yeast related issues such as fungal acne should watch for flare ups since Galactomyces is a yeast ferment.

The ingredient is produced from plant leaves and a microorganism that is not derived from animals so it is considered suitable for vegans and vegetarians.

No studies suggest any risk for pregnant or breastfeeding women when the extract is used topically in normal cosmetic amounts. Still this is not medical advice and anyone who is pregnant or nursing should check with a healthcare professional before adding new products.

Galactomyces/Olive Leaf Ferment Extract does not increase photosensitivity so there is no special sun care concern beyond the usual daily SPF habit.

Potential Side Effects/Adverse Reactions

Responses to topical Galactomyces/Olive Leaf Ferment Extract vary from person to person. The following outlines potential reactions yet most users will not experience them when using a well formulated product.

  • Skin irritation such as redness stinging or itching
  • Allergic contact dermatitis in individuals sensitive to olive leaf components or yeast ferment by-products
  • Breakouts or flare ups of fungal acne in those predisposed to Malassezia overgrowth
  • Rare hives or swelling in highly reactive skin

If any of these effects occur stop using the product immediately and seek advice from a medical professional if symptoms persist or worsen.

Comedogenic Rating

Rating: 1/5

Galactomyces/Olive Leaf Ferment Extract sits on the skin as a thin, breathable film and has a low oil content, so it rarely blocks pores. The fermentation process also breaks down heavier olive compounds into lighter molecules that are less likely to congest skin. Because of this, most people prone to acne or blackheads can use it without problems, though those highly sensitive to any yeast derivative should monitor their skin.

No notable impurities or heavy lipids are introduced during production, which helps keep the comedogenic risk low.

Summary

Galactomyces/Olive Leaf Ferment Extract is mainly an emollient, softening the skin surface and improving product spreadability by forming a light conditioning layer. Fermentation adds amino acids, vitamins and organic acids that boost its skin-friendly profile.

First popularized in Korean and Japanese beauty circles, it enjoys moderate but steady use worldwide, especially in hydrating toners, essences and masks where a weightless feel is valued.

Topically it is considered very safe, with few reports of irritation and a low comedogenic rating. Still, skin can be unpredictable so it is wise to patch test any new product containing this ingredient before applying it to your whole face.

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