PDRN, exosomes and ferments: the actives of K-beauty in 2026

On the shelves of Myeongdong, a bottle announces "salmon DNA" with no further explanation. The claim is neither a metaphor nor a slip: the molecule sold under the abbreviation PDRN really is extracted from salmon milt, and its history does not begin in a Korean cosmetics lab but in an Italian pharmaceutical company in the 1950s, where it was used to heal burns.

Korean skincare in 2026 is organised around three families of actives, each with a distinct trajectory: ferments, an old industrial legacy; PDRN, a drug that migrated to the shelf; and exosomes, a biotech frontier still loosely regulated. Telling them apart makes it possible to read a label instead of believing it.

Ferments, the historical base of K-beauty#

Fermentation is the oldest of the three pillars, and the best documented. The founding story belongs to the Japanese industry: in the 1970s, researchers noticed that the hands of elderly workers in a sake brewery stayed smooth despite the labour. The observation led to isolating a yeast, Galactomyces, whose fermentation filtrate became the single active in the product launched in 1980 as Pitera by SK-II.

The Korean industry took over the category through the 2000s and 2010s and democratised it. Treatment essences built on ferment filtrate multiplied at far lower prices, and fermentation became a cultural argument as much as a technical one: Korea has been making its nuruk, the starter used for rice alcohols, for centuries, and rests part of its cuisine on fermented soy pastes.

What fermentation brings to a cosmetic comes down to three measurable effects. It splits large molecules into smaller fragments, easier to diffuse. It produces metabolites absent from the raw material: amino acids, short peptides, organic acids. And it stabilises some preparations by lowering pH. The commonest filtrates appear under readable INCI names: Galactomyces ferment filtrate, Bifida ferment lysate, Saccharomyces ferment filtrate, Lactobacillus ferment.

PDRN, a hospital molecule that moved to the shelf#

PDRN, for polydeoxyribonucleotide, is a mixture of purified DNA fragments extracted from the milt of salmon or trout after protein removal. Its medical career long predates its aesthetic use: the Italian firm Mastelli has marketed a PDRN-based product for tissue repair and wound healing for several decades.

The mechanism proposed in the literature is twofold. The fragments act as agonists of the adenosine A2A receptor, involved in regulating inflammation and stimulating collagen synthesis. They also supply nucleotides that cells can reuse directly, what biology calls a salvage pathway. That work concerns injectable forms and medical indications: transposing it to a cream without reservation would be an extrapolation.

Korea industrialised the injectable aesthetic version. The best known product, launched in 2014 by the Pharma Research laboratory, is known colloquially as 연어주사 (yeoneo jusa), "salmon injection". It contains not PDRN but PN, polynucleotide, longer chains that form a gel and provide mechanical support on top of the biological role. The distinction is real and rarely explained in shops: PDRN is closer to a signal, PN closer to a structure.

The move to topicals came next, with a wave of serums and creams claiming PDRN from 2024 onwards. Caution applies on this precise point: a molecule that size crosses an intact stratum corneum poorly, and manufacturers who account for that pair their formula with carriers or microneedles. A PDRN serum remains a respectable hydrating and soothing product; it does not equal a procedure performed under the skin.

Exosomes, a poorly marked frontier#

Exosomes are extracellular vesicles of thirty to one hundred and fifty nanometres, released by nearly every living cell and loaded with proteins, lipids and RNA. Their biological function is established: they are messengers between cells. Their cosmetic use, however, runs into three obstacles.

The first is regulatory. Korean cosmetics law forbids ingredients derived from human tissue, which excludes human stem cell exosomes from products sold on shelves. In the United States, the drug agency issued a public warning as early as December 2019 about unapproved regenerative products, exosomes included, after serious infections in patients treated outside any framework.

The second is analytical. Isolating exosomes reproducibly, counting them and guaranteeing their contents remains difficult, and many products sold under that label in fact contain cell lysates or uncharacterised vesicular fractions. Marketing language accommodates this with careful phrasing such as "exosome-inspired technology".

The third is botanical, and it is the route the Korean market has taken: plant exosomes, extracted from rose, edelweiss or centella cell cultures, sidestep the ban on human material. They are easier to produce and raise fewer ethical questions, but the demonstration of their effect on human skin remains, at this stage, thinner than the discourse around them.

Why Korea moves so fast#

The speed at which these ranges renew comes from an industrial peculiarity. Two Korean contract manufacturers, Cosmax and Kolmar Korea, rank among the largest cosmetics makers in the world and produce for hundreds of brands, Korean and foreign. An independent brand can therefore launch a formula without owning a factory or a laboratory, in a matter of months.

The regulatory framework accelerates things too. Korea recognises a category of functional cosmetics, subject to validation by the national health agency, which allows precise claims such as wrinkle improvement or brightening. That category gives claims an evidence framework few markets provide with the same clarity.

The result shows in customs data: Korean cosmetics exports reached a record above ten billion dollars in 2024, driven by brands the general public had not heard of five years earlier.

Reading a label without being taken in#

Four reflexes are enough to bring these promises back to scale.

Look for the INCI name rather than the front-of-pack argument: polydeoxyribonucleotide for PDRN, Galactomyces ferment filtrate for a ferment, a plant cell culture name for a supposed exosome. Check its position in the list, bearing in mind that no regulation requires disclosing the exact concentration of actives. Consider the whole formula, because a good ferment drowned in a perfumed, alcohol-heavy base will still irritate sensitive skin. And remember that a product promising the result of a medical procedure at the price of a serum implies one of two things: either the result is more modest, or the product should not have been on the shelf.

Read alsoGlass skin: the Korean method, what it does and what it cannot

Almost all these actives serve the same aesthetic goal: glass skin, its protocol and its limits.

Read alsoK-beauty: the Korean skincare routine that conquered the world

The complete Korean routine, in which these three families of actives sit at the essence, serum and cream steps.

What the next wave looks like#

The three families converge on one logic: bringing home care closer to the clinical gesture. Ferments come from food processing, PDRN from pharmacy, exosomes from cell biology; none was born in a cosmetics lab. That transfer, more than the molecules themselves, defines the K-beauty of this decade.

Consumers gain remarkable textures and formulas better tolerated than those of ten years ago. They lose the ability to verify what they are buying on their own, because the gap has widened between the level of proof demanded of a drug and the level that suffices to sell a bottle. Between salmon milt and the shelf lie seventy years of research: that deserves better than one word on a box.

FAQ#

What exactly is PDRN? Polydeoxyribonucleotide is a mixture of purified DNA fragments extracted from salmon or trout milt. Used in medicine for several decades for wound healing, it acts notably on the adenosine A2A receptor and supplies nucleotides that cells can reuse.

What is the difference between PDRN and PN? PN, polynucleotide, consists of longer chains that form a gel and add mechanical support to the biological signal. PDRN is made of shorter fragments whose action is closer to signalling. The Korean "salmon" injections most often use PN.

Is a PDRN cream worth an injection? No. A molecule of that size penetrates an intact stratum corneum poorly, and injections are a medical act performed in the dermis. A topical PDRN product can soothe and hydrate, which is already useful, but it does not reproduce the effect of a procedure under the skin.

Are exosomes allowed in cosmetics? Exosomes derived from human cells are excluded from Korean cosmetics, since national regulation forbids ingredients of human tissue origin. Products on shelves therefore rely on plant sources or on cell fractions, and injecting exosomes for aesthetic purposes is not approved in many countries.

Are ferments better than classic actives? They replace neither a sunscreen, nor a retinoid, nor a well formulated moisturiser. Their benefit on hydration and comfort is real, with generally good tolerance, but no data supports claiming that a fermentation filtrate outperforms reference actives on wrinkles or pigmentation.

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Photo credits: the images in this article come from Wikimedia Commons and are under a free license.