The Science Behind Korea’s Most Unconventional Skincare Ingredients

AUTHOR - DR. DAVID JACK

Korean skincare is synonymous with innovation. Known for pushing the boundaries of formulation and function, South Korea’s beauty industry continues to surprise the Western market with actives that seem, at first glance, unconventional. From ‘glass skin’ serums to ampoules infused with ingredients you’d more typically associate with a biology lab than your bathroom shelf, the Korean beauty (K-beauty) world continues to redefine and push the boundaries of skincare science. For the curious and discerning alike, this guide explores the evidence (and limitations) behind some of the more unconventional ingredients cropping up in Korean skincare - from snail mucin to salmon sperm DNA, bee venom to mugwort - I explore the most headline grabbing ingredients - how they work, the evidence supporting their use, and why they’ve become cult favourites.

Snail Mucin: Nature’s Collagen Factory?

Snail mucin - technically ‘snail secretion filtrate’ - is one of the most well-known ‘weird’ ingredients to come out of Korean skincare. Initially a surprising trend, its efficacy is now supported by a growing body of scientific literature. Snail mucin is secreted through four specialised glands in the ‘foot’ of the snail’s - a viscoelastic material essential for the animal’s locomotion, hydration and defence. In skincare, this biologically rich substance is prized for a very different reason: its exceptional skin-repairing potential. For vegans and vegetarians, the idea of smearing this on one’s face might not be overly appealing, so a synthetic vegan alternative is thankfully available, containing all of the same glycoproteins and vitamins. I’ve included this in all of my daily trio products as the benefits of this ingredient are substantial.

How does Snail Mucin work?

The specific composition of the natural snail mucin varies based on snail diet, climate, and breeding environment of the snails in question. Generally rich in allantoin and glycolic acid, snail mucin has been shown to stimulate collagen production, promote cell turnover, and improve hydration by increasing water retention in the extracellular matrix of the skin. Its naturally occurring glycoproteins, proteoglycans and copper peptides, including the antimicrobial compound achacin, are paired with organic acids (such as lactic, citric and tartaric acids) that contribute to its gentle exfoliating and antibacterial properties. 

All in, these molecules can help accelerate wound healing, increase fibroblast proliferation, and enhance collagen synthesis (Pagano et al., 2024). It also contains allantoin and zinc, which support anti-inflammatory pathways to calm inflammation (so are helpful in conditions such as rosacea and acne), and hyperpigmentation. While widely used in K-beauty anti-ageing serums, its applications in wound healing and barrier repair are increasingly being studied from a clinical point of view.

Snail mucin is typically found in serums and essences, used after cleansing and before moisturiser. It layers well with hydrating ingredients such as hyaluronic acid, and the vegan version can be found in my antioxidant serum.

PDRNs (Polydeoxyribonucleotides): The Salmon Sperm Facial

If snail mucin raised a few eyebrows, PDRNs might raise a few more. Polydeoxyribonucleotides (PDRNs), extracted from the sperm of salmonid fish such as Oncorhynchus mykiss (rainbow trout), may sound unconventional, however, their regenerative power is firmly rooted in molecular science.

PDRNs are short chains of DNA fragments, with a structure remarkably similar to human DNA. Their skincare use stems from their ability to stimulate cellular regeneration, enhance wound healing, and reduce inflammation - effects first explored in burn treatment and diabetic ulcers, and now increasingly translated into cosmetic dermatology.

These DNA fragments bind to adenosine A2A receptors, triggering a cascade of anti-inflammatory and pro-healing signals as well as promoting angiogenesis (formation of new blood vessels). They also stimulate fibroblast proliferation and collagen synthesis, resulting in improving skin elasticity, texture and overall tone.

Several years of clinical research supports their efficacy in both wound healing and skincare usage. A 2016 study published in Mediators of Inflammation found that PDRNs significantly enhanced skin repair and regeneration in both in vitro and animal models. In the clinical realm, injectable PDRN formulations (like Rejuran®) have been shown to improve fine lines, acne scarring and increase dermal thickness. While topical versions are less potent than their injectable counterparts due to skin barrier limitations (indeed long term clinical data on solely topical use is limited) - the molecules are relatively large and may not penetrate deeply without delivery enhancers. This being said, they offer significant benefits when used after procedures and techniques to aid dermal penetration, including microneedling, chemical peels and fractional laser treatments.

The key drawback of PDRNs in skincare is the size of molecules, limiting penetration into the dermis of the skin. This being said, PDRNs are non-immunogenic, meaning they carry a very low risk of allergic reactions (despite being derived from fish), making them suitable for sensitive or compromised skin. Additionally, while ethical concerns around animal-derived ingredients are generally low (the DNA is extracted from salmon bred for food), it's important to choose clinically validated formulations from reputable sources.

Bio-Placenta: Placental growth factors for skin rejuvenation

Bio-placenta is a synthetic complex that mimics the peptide-rich composition of human placental extract, without any animal or human tissue. It’s composed of five key growth factors: EGF, IGF-1, aFGF, bFGF, and VEGF - each of which has skin-regenerating functions.

How does Bio-Placenta help the skin?

Placental growth factors benefit the skin, and in hair growth, by regulating key cellular processes including proliferation (cell division), differentiation (i.e. regulating function) and collagen synthesis. EGF (epidermal growth factor) in particular has been shown in studies to increase skin cell regeneration and aid in wound healing. In cosmetic formulations, the inclusion of bio-placenta peptides and co-factors is believed to enhance skin firmness and elasticity, so is ideal in anti-ageing productBio-placenta products are typically applied at night, directly after cleansing - or integrated into a moisturiser. Their small molecular size allows for decent absorption, particularly when used after mild exfoliation (e.g. our Blue Peel). They are ideal for patients who are in their 30s and beyond, looking to firm and rejuvenate the skin.  

Hydrolysed Rocket Leaf Extract: A natural Glutathione booster

Often found in your salad bowl, rocket leaf (Eruca sativa or arugula in the US) is rapidly becoming a quiet force in skincare - not just for its culinary appeal, but for its potent antioxidant and detoxifying properties, particularly its role in enhancing glutathione synthesis in the skin.  Rocket leaf extract, particularly in its hydrolysed form, is rich in sulphur-containing glucosinolates, especially glucoraphanin, which is enzymatically converted into sulforaphane — a well-studied compound known to activate the body’s endogenous antioxidant pathways.

One of its most important effects in the skin is the stimulation of glutathione synthesis. Glutathione is the body's master antioxidant, crucial for neutralising free radicals, repairing oxidative damage, and regulating melanogenesis (shifting production of melanin from the pigmented eumelanin form, to a lighter form known as phaeomelanin). In keratinocytes and fibroblasts, glutathione supports healthy mitochondrial function, reduces inflammation, and protects against UV-induced damage, making it a key player in anti-ageing and pigmentation control. It’s effect on melanin production is particularly notable as it can help reduce hyperpigmentation in a different way than many other pigmentation treatments.

In addition to glutathione support, rocket leaf contains vitamin C, beta-carotene, and flavonoids such as quercetin and kaempferol, further enhancing its antioxidant profile. Its anti-inflammatory properties also make it a promising active for sensitive, rosacea-prone, or post-procedure skin.

Hydrolysed rocket extract is typically found in lightweight serums and moisturisers (I include it in all of my daily skin trio products as a way of shielding  the skin from daily environmental stressors. It pairs well with UV filters, niacinamide, and vitamin C for a layered antioxidant approach.

Mugwort: Korea’s Herbal Hero

Known as “ssuk” in Korean traditional medicine, mugwort (Artemisia vulgaris and Artemisia princeps) has been used for centuries in Korea as a remedy for inflammatory skin conditions such as acne. It’s now earning its place in modern dermocosmetic formulations thanks to its calming, antimicrobial and antioxidant properties.  What sets mugwort apart is its multifunctional role in skin health. It is naturally rich in flavonoids, coumarins, terpenoids, and phenolic acids - all compounds with proven anti-inflammatory and antioxidant action. These bioactives help to reduce erythema (i.e. redness), inhibit the release of potentially damaging inflammatory cytokines (such as TNF-α and IL-6), and protect the skin from environmental aggressors including UV light and heavy metal pollution.  Mugwort also helps reinforce the skin’s barrier function by supporting synthesis of ceramides and increasing epidermal hydration - making it good for post-treatment care or those with chronic skin barrier dysfunction. It has also been shown to reduce levels of S. aureus and P. acnes bacteria, making it a strong candidate for skincare designed to manage blemish-prone skin and acne. 

In Korean skincare, fermented Artemisia extracts are especially prized. The fermentation process breaks down the plant’s active compounds into smaller, more bioavailable molecules, potentially improving absorption and efficacy. This is why you’ll often find mugwort in essences, ampoules, and first-step toners - products designed to deliver potent hydration and calming benefits at the earliest stage of your skincare routine. It is generally used after cleansing and before heavier serums or creams and is suitable for both morning and evening use.

Mugwort is very versatile and pairs well with niacinamide, hyaluronic acid and ceramides - ideal for calming and barrier-restoring products. Mugwort is very well tolerated by most skin types. However, individuals with mugwort or ragweed allergies (as both are in the Asteraceae family) should patch test first. 

Bee Venom in treatments: a substitute for injectable toxins?

Dubbed “nature’s b’tox” by beauty insiders, bee venom may sound extreme but this natural peptide cocktail is gaining credibility for its ability to stimulate collagen, reduce fine lines and revitalise dull, ageing skin.

Bee venom contains a mix of bioactive peptides, including melittin, apamin, phospholipase A2, and hyaluronidase. When applied topically, these compounds simulate a very mild, localised inflammatory response, effectively mimicking the physiological conditions of a micro-injury without damaging the skin. This triggers the skin’s repair and regeneration processes, including proliferation of fibroblasts (the cells that produce collagen and elastin) and increasing blood circulation to the treated area.

Melittin, the primary component of bee venom, has been shown to modulate inflammatory pathways and enhance skin healing. Indeed, a randomised, placebo-controlled trial published in the Journal of Drugs in Dermatology found that twice-daily application of a bee venom serum for 12 weeks led to statistically significant improvements in wrinkle depth, skin texture and elasticity. Whilst other in vitro studies have highlighted it’s its role in upregulation of type I collagen resulting in dermal remodelling.

Bee venom also has antibacterial activity, particularly against P. acnes bacteria, making it potentially helpful for inflammatory acne when used in low, non-irritating concentrations.

Bee venom, a staple in K-beauty products, is typically found in serums, sleep masks and sheet masks, often combined with other active ingredients like niacinamide, peptides or hyaluronic acid. It is best used in the evening, 2–3 times per week, after cleansing and toning and before moisturiser.

For anti-ageing or loss of firmness, it can complement other collagen-stimulating products such as retinol or peptides - though it’s advisable to alternate these actives to avoid over-stimulation. It also pairs well with barrier-repair products like our Blue Peel if mild irritation occurs. 

Centella Asiatica (Cica/Tiger Grass): The Dermal Healer

Centella Asiatica, affectionately known in K-beauty as Cica or Tiger Grass is far more than just a passing K-beauty trend. This centuries-old medicinal plant is now one of the most clinically substantiated natural actives in modern dermatology, prized for its ability to heal, soothe and strengthen the skin barrier.

Centella is rich in four key triterpenoid compounds: asiaticoside, madecassoside, asiatic acid, and madecassic acid. These have been shown to stimulate fibroblast activity, enhance collagen synthesis and support the repair of damaged skin, making it ideal for sensitive, inflamed or post-procedure skin.

Centella has a long history in traditional medicine, particularly in Ayurvedic and Chinese pharmacopeia. But its benefits have been rigorously validated in modern science too. Clinical studies have shown that topical application of Centella extracts improves wound healing, reduces inflammation and strengthens the dermal matrix by upregulating the production of type I collagen in the dermis of the skin.Cica is also known to reduce the production of pro-inflammatory mediators like IL-1β and TNF-α, making it highly suitable for those suffering from inflammatory skin issues including rosacea, eczema or acne. 

How does Cica fit into a skincare routine?

Centella Asiatica is most often found in soothing creams, recovery serums or overnight soothing masks. It combines well with nearly every other ingredient, including retinoids, alpha hydroxy acids and vitamin C. This makes it a key buffering or support ingredient for skin cycling routines or post-treatment repair.

I recommend layering Centella-based products as your final cream step, particularly after in-clinic treatments, or by integrating it into your everyday routine if your skin is prone to sensitivity or reactivity. Our Face Paint: SOS is ideal here, combining anti-inflammatory actives with barrier support and hydration.

From snail secretion to salmon DNA, Korean skincare ingredients continue to push the boundaries of cosmetic science. While some may seem eccentric at first glance, many of these ingredients have promising - and in some cases substantial - evidence behind them. As with all things skincare, it’s about understanding what your skin truly needs and choosing well-formulated products that deliver these ingredients in effective, evidence-led combinations.

Pagano, C., Ceccarini, M. R., Marinelli, A., Imbriano, A., Beccari, T., Primavilla, S., ... & Perioli, L. (2024). Development and characterization of an emulgel based on a snail slime useful for dermatological applications. International Journal of Pharmaceutics, 660, 124337. https://www.sciencedirect.com/science/article/pii/S0378517324005714