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Polyglutamic acid serum OEM/ODM manufacturing
Polyglutamic Acid (PGA) Serum · OEM/ODM
Polyglutamic acid (PGA), specifically poly-γ-glutamic acid, is a long chain of glutamic acid units produced by Bacillus bacteria during fermentation; it is also what makes the stringy, sticky coating of natto, the Japanese fermented soybean dish. The cosmetic raw material is made by controlled fermentation, not extracted from natto. PGA is often marketed as a humectant "stronger than hyaluronic acid", but the current data do not support that: in a laboratory test, commercial PGA hydrated about as well as hyaluronic acid and glycerol; the skin barrier marker results come from cultured cells and a reconstructed skin model; and we have not found any controlled human trial of a cosmetic containing PGA. One point that is rarely mentioned: PGA is the main allergen in natto allergy. The Butter-C polyglutamic acid serum is therefore positioned at the right level: it helps hold moisture and leaves skin feeling moisturized and smooth, with claims tested on the finished product and a label note for people allergic to natto. PGA is not currently stocked at the plant, so it is sourced per order, with a COA. Butter-C offers turnkey OEM/ODM manufacturing, from formula development and testing to labeled finished goods and the notification dossier.
Formula base
A light water base with PGA as the named humectant
PGA dissolves in water, so the serum is built on an oil-free water base. PGA is the named ingredient, supported by familiar humectants; a polymer-rich water base supports microbial growth, so the preservative system must be confirmed by a challenge test.
Polyglutamic acid
INCI Polyglutamic Acid; a salt form, if offered, may carry a different INCI name, so check the COA and technical data. PGA is a polymer with no single fixed molecular weight; molecular weight drives viscosity, so the COA should state molecular weight and purity.
Supporting humectants
Glycerin, Butylene Glycol, Betaine, Panthenol; Sodium Hyaluronate at a low level for a layered hydrating feel. Glycerin and the base are the main basis for a moisturizing claim measured on the finished product.
Viscosity framework
Xanthan Gum or Hydroxyethylcellulose; Carbomer neutralized with Sodium Hydroxide for a clear gel. PGA adds some viscosity depending on molecular weight, so it is finalized on the full formula.
Preservation and stability
Phenoxyethanol up to 1% (ASEAN Annex VI) with Ethylhexylglycerin; Disodium EDTA. An ISO 11930 challenge test is mandatory.
Key technical points
Four points specific to a serum named after PGA
The hydrating serum base is covered on the general page; the four items below center on the polyglutamic acid raw material itself.
Current data: laboratory, not yet in humans
Parati et al. (2024): in a laboratory test, commercial PGA hydrated about as well as hyaluronic acid and glycerol, and PGA fermented on seaweed hydrated more; creams containing 0.2–2% (w/v) seaweed PGA showed no negative effect on HaCaT keratinocytes. Ko et al. (2025): in cultured keratinocytes, PGA dose-dependently increased gene expression of filaggrin, involucrin, loricrin and aquaporin 3; in a reconstructed skin model, topical 1% PGA raised filaggrin, involucrin, CD44 and aquaporin 3 compared with control. Most authors are company employees, and the authors note that longer-term research is needed. We have not found any controlled human trial of a cosmetic containing PGA, so the evidence is limited.
Natto allergy: a label note
PGA is an allergen in natto, an allergy that typically causes late-onset anaphylaxis. Inomata et al. (2018), a survey of 140 food allergy patients: all 13 patients with natto allergy tested positive to PGA on skin prick and basophil activation tests; of these 13, 92.3% had a marine sport hobby, especially surfing (84.6%). The authors' hypothesis is sensitization through the skin from jellyfish stings, since jellyfish tentacles also produce PGA. Shigeno et al. (2024) reported one case of anaphylaxis in a 49-year-old surfer and advised people suspected of PGA allergy to avoid PGA-containing products. The label should carry a note for people allergic to natto; people who have had an allergic reaction after a jellyfish sting should ask an allergist before use.
Viscosity follows molecular weight
Creams containing PGA became thinner as shear rate increased; commercial PGA did not significantly change cream rheology in the Parati (2024) study, which the authors attributed to similar molecular weight. A PGA lot with a different molecular weight gives a serum with a different viscosity: measure viscosity per lot, and check clarity when combining with HA or other negatively charged polymers.
pH, heat and regulations
The sources we checked give no stable pH range or heat limit for PGA in a formula, so these are set from technical data and stability testing. Polyglutamic acid is not listed in ASEAN Annexes II, III or VI (June 2026 release); zinc glutamate in Annex III, Ref 24, is a different substance. The sources we checked include no CIR report on PGA. The use level in a commercial product follows the supplier's technical data.
Three formulation directions
Three types of polyglutamic acid serum
Watery PGA serum
PGA, glycerin, betaine; lightly viscous, absorbs quickly, used after toner, morning and evening.
PGA – HA serum
Adds low-level Sodium Hyaluronate and Panthenol; PGA stays the named ingredient, unlike the hyaluronic acid serum, where HA is named and several molecular weights are combined.
Light gel for oily skin
Thickened with Hydroxyethylcellulose or Carbomer, oil-free; dries quickly, suited to hot, humid climates.
Packaging is designed with the formula
Pump or airless bottles limit contamination in use; dropper bottles expose the product to fingers and air more, so they need a stricter challenge test.
Parameters we monitor
What our R&D lab measures on every sample
Below are the parameters Butter-C monitors during formula development and scale-up to production. Specific limits are agreed with you on the approved sample and then written into the product's in-house specification.
- Appearance & clarity
- Color, odor, clarity; watch for haze or precipitation over time.
- pH
- Measured at 25°C; kept within the stable range of the PGA raw material (per technical data) and the preservative system.
- Viscosity
- Rotational viscometer at 25°C at several speeds; viscosity varies with the molecular weight of the PGA lot.
- Incoming PGA
- COA checked for every lot: INCI name, molecular weight, purity, microbiology; a statement on the fermentation medium if you position the product as vegan.
- Stability
- Accelerated aging at 40°C, freeze–thaw cycling, light exposure; watch viscosity, clarity, pH.
- Microbiology & preservative challenge
- Tested at a GLP / ISO 17025-accredited laboratory; preservative efficacy (challenge) test per ISO 11930.
- Irritation & sensitization
- Volunteer testing before the formula is finalized; required if the label says "suitable for sensitive skin".
- Skin hydration
- Instrument measurement on volunteers against the plain base, when you want a moisturizing figure.
Claims
Claims at the moisturizing level
The hydration data on PGA come from a laboratory test, and the filaggrin data from cells and a reconstructed skin model. Butter-C reviews the wording on the label and marketing materials as soon as the notification dossier is prepared.
Helps hold moisture, leaves skin feeling moisturized and smooth
Figures are stated only after measurement on the finished product. Instead of: "holds many times more water than hyaluronic acid", "stronger than HA".
Contains polyglutamic acid from fermentation
As declared by the supplier. Instead of: "extracted from natto", "all-natural".
Helps skin feel soft, smooth and supple
Requires testing on the finished product. Instead of: boosting filaggrin, strengthening the skin barrier, increasing the skin's own hyaluronic acid; those data exist only in cells and reconstructed skin.
For daily use, morning and evening
As part of a daily skincare routine. Instead of: anti-aging, plumping wrinkles, skin restoration.
Allergy note
People diagnosed with natto allergy or suspected of PGA allergy should not use it; people who have had an allergic reaction after a jellyfish sting, or who are unsure, should ask an allergist before use. Test on a small area of skin before use; stop if redness or itching occurs. Instead of: "hypoallergenic", "safe for everyone".
Pregnant women
No specific recommendation exists; the label and our advice suggest asking a doctor.
Manufacturing specifications
Our capabilities
- Texture
- Lightly viscous liquid or light gel; clear to slightly hazy depending on the raw material and thickener.
- Pack formats
- Pump bottle, airless pump or dropper bottle. Volume agreed when selecting packaging.
- PGA sourcing
- Not stocked at the plant; sourced per order, with a COA required for every lot.
- Minimum order quantity
- Agreed per order, depending on the PGA raw material, formula direction and pack format.
- Testing
- Performed at a GLP / ISO 17025-accredited laboratory; certificate of analysis delivered with every lot.
- Documentation
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with a PGA COA stating INCI name, molecular weight and purity.
- Packaging
- Label design, printing and packing run in parallel with formula development.
Suggested product concept
Fragrance-free PGA serum for dehydrated skin
A product direction to help you picture the concept, not a ready-made product for sale. The actual formula is developed to fit your brand's positioning and price range.
Polyglutamic acid
The named ingredient; fermentation-derived, with a COA stating molecular weight and purity.
Glycerin, Betaine
Hold moisture in the stratum corneum, the main basis for a moisturizing claim measured on the finished product.
Low-level Sodium Hyaluronate
Additional humectant at a low level so the serum is not sticky.
30 ml pump bottle, fragrance-free
Limits contamination in use; the label carries a note for people allergic to natto and a reminder to test on a small area of skin.
Customization options
What you can specify
The same product type can be aimed at very different customers. Tell us your requirements in the areas below and our pharmacists will develop a matching formula.
Texture
Lightly viscous liquid or light gel, which decides the thickener and the feel on application.
Supporting ingredients
Sodium Hyaluronate, Panthenol, Betaine; choose a few, not many.
Target market
For markets where natto is commonly eaten (Japan), consider stating the allergy note clearly on the label and in the dossier.
Fragrance and color
We recommend fragrance-free and color-free.
Ingredient positioning
Alcohol-free, fragrance-free, vegan; PGA is a fermented raw material, and a vegan claim needs the supplier's statement on the fermentation medium and is assessed on the whole formula.
Packaging
Pump, airless or dropper, which sets how strict the challenge test must be.
Further reading
Related knowledge
Polyglutamic acid (PGA) in cosmetics
Fermentation production, cell and skin model data, tested concentrations, natto allergy note (in Vietnamese).
Hyaluronic acid serum OEM/ODM manufacturing
The general page on hydrating serums, where hyaluronic acid in several molecular weights is the named ingredient.
Beta-glucan essence OEM/ODM manufacturing
Another humectant polymer named in a water-based essence; the data are not shared.
Hyaluronic acid in cosmetics
The humectant PGA is most often compared with (in Vietnamese).
Dry skin and dehydrated skin
Telling oil-deficient skin from water-deficient skin to choose the serum texture (in Vietnamese).
How we work
From idea to finished batch
Eight steps and three milestones signed off by both sides: approved sample, notification number, finished batch. Step-by-step details (in Vietnamese) →
Get started
Tell us about the product you plan to launch
Send us your product direction and expected volume. Our team will get back to you during business hours (Vietnam time, GMT+7).
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