For two decades, hyaluronic acid was the answer to almost every hydration question in Korean skincare. It was inexpensive, well-understood, regulator-friendly, and the consumer knew the name. That is now changing. Polyglutamic acid — PGA — is moving from a specialist ingredient into mainstream formulation, and the brands paying attention have already started reformulating.
What PGA Is
Polyglutamic acid is a biopolymer produced by Bacillus subtilis fermentation, the same fermentation tradition that gives Korean cuisine cheonggukjang and natto. In skincare, it is a high-molecular-weight humectant that binds water molecules to the skin’s surface and lower epidermal layers.
The headline number is straightforward: peer-reviewed studies place PGA’s moisture-holding capacity at roughly four to five times that of hyaluronic acid by weight. But the more interesting properties are structural. Where hyaluronic acid forms a hydration film that evaporates relatively quickly, PGA creates a more durable hydrogel layer that continues to bind atmospheric moisture throughout the day. The functional difference, on real skin in real climates, is hours of hydration rather than tens of minutes.
Why Korean Brands Are Switching
The category-shifting moment came when major Korean indie brands — Mixsoon being the most-cited example — began featuring PGA at hero-ingredient concentrations rather than as a supporting humectant. That signaled to formulators that consumers were ready to accept a new ingredient name on the label, which had been the main barrier.
Three other factors accelerated adoption:
Synergy with existing actives. PGA does not compete with retinol, niacinamide, or vitamin C the way some humectants do. It actually buffers the irritation profile of those actives by maintaining barrier hydration, which means formulators can pair it with stronger active concentrations without consumer pushback on sting and redness.
Clean-beauty positioning. PGA is fermentation-derived, vegan, and biodegradable. For brands targeting the EU and US clean-beauty channels, the ingredient story writes itself. Hyaluronic acid is technically also clean-compatible, but PGA’s “Korean fermentation heritage” gives it a narrative hook hyaluronic acid lost a decade ago.
Manufacturing economics. Korean PGA suppliers have moved up the scale curve faster than expected. The price per kilogram has dropped roughly 40% over the past two years, putting it within range of mass-market formulations rather than only ultra-premium SKUs.
How to Position PGA in a Product Line
PGA is not a one-for-one replacement for hyaluronic acid. The two ingredients are complementary, and the smartest Korean formulations use both. Hyaluronic acid (especially low-molecular-weight) penetrates and holds moisture in the deeper epidermis; PGA holds it at the surface. A product that uses 0.3% PGA on top of a hyaluronic acid base will outperform either ingredient used alone.
For B2B buyers evaluating Korean OEM/ODM partners on PGA formulations, three things matter:
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Source documentation. Bacterial-fermentation-derived PGA varies in purity, residual protein content, and molecular weight distribution. Spec sheets should include molecular weight range and endotoxin levels, not just “PGA from fermentation.”
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Texture engineering. PGA at meaningful concentrations introduces a slight tackiness that consumers can dislike. Korean formulators have developed several techniques to neutralize this — pairing with light silicone esters, using specific polymer ratios, or microencapsulation. Ask to see a finished formulation, not just an ingredient sample.
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Claim language. “Five times the hydration of hyaluronic acid” is a defensible claim with the right substantiation file, but it is also a claim that invites regulatory scrutiny in some markets. Pre-clear the exact wording for each launch region.
The Bigger Pattern
PGA is part of a broader shift in Korean skincare from “ingredient lists that consumers recognize” to “ingredient lists that perform better under measurement.” Polyglutamic acid, beta-glucan, succinoyl chitosan, and ectoine are all in the same movement: better humectants, fermentation-derived, ready to leave hyaluronic acid in the position of a default rather than a hero.
For OEM/ODM portfolios being built for 2027 launches, PGA should be on every hydration SKU under consideration. The brands that wait until it is on every shelf will have missed the credible-early-mover window.