In which treatments can we find polyglutamic acid?

The polyglutamic acid (PGA) is derived from the polymerisation of the amino acid L-glutamic. This biopolymer was first found in the bodies of marine jellyfish, then researchers highlighted its presence in the mucilage of fermented soybean seeds, a traditional Japanese dish called "nattō". In recent years, the polyglutamic acid has also been used in the cosmetic field, where it serves as an excellent skin moisturiser. It indeed has very good humectant properties : once applied to the skin, it swells and traps water molecules in a molecular structure called a microgel. This microgel is capable of retaining up to 5,000 times its weight in water, but also of inhibiting the action of hyaluronidase, the enzyme responsible for the degradation of hyaluronic acid. The polyglutamic acid is thus an interesting active ingredient for hydrating the skin but also for preventing and smoothing fine lines. It is found in various types of care, generally at concentrations between 0.3 and 3%:

• Serum : Polyglutamic acid is most commonly found in serums, typically intended for dehydrated skin. Thanks to its polymeric structure, it forms a flexible mesh on the skin's surface, preventing water from evaporating without weighing down the skin. The good tolerance of polyglutamic acid also allows it to be combined with exfoliating agents, such as glycolic acid or lactic acid, to limit their potential for irritation.

• Moisturising Cream : Polyglutamic acid can also be found in moisturising creams designed for the face or body, for reasons similar to those explaining its inclusion in serums. In addition to its ability to retain water, it has film-forming properties, allowing it to trap moisture in the epidermis and strengthen the skin's barrier function.

• Face Mask : Masks enriched with polyglutamic acid are often used to provide the skin with intense hydration. Whether they are in fabric, gel, or cream form, they allow the active ingredient to be in prolonged contact with the skin, which promotes its absorption. Masks based on polyglutamic acid are particularly beneficial when the skin needs to reinforce its barrier function, for instance in winter when temperatures drop or after an exfoliation session.

• Eye Contour : The eye contour is a sensitive area, lacking in sebaceous glands and often prone to dehydration. Polyglutamic acid is therefore particularly suitable for its care. Treatments designed for the eye contour that contain polyglutamic acid help to reduce dehydration fine lines, common in this area, and also to plump the skin.

At Typology, we have chosen to incorporate polyglutamic acid into several of our treatments:

• The plumping serum : Containing 3% polyglutamic acid and red algae, this serum is suitable for all skin types and is particularly recommended for dehydrated skin. On one hand, polyglutamic acid forms a protective film on the surface of the epidermis, limiting insensible water loss, and retains water molecules. On the other hand, the red algae extract stimulates the production of hyaluronic acid by the dermal fibroblasts, thus enhancing the skin's natural hydration.

• The cryo-plumping stick for face and eyes : This convenient format treatment has an ice-cube effect for immediate plumping and decongesting action. It can be used on both the face and around the eye contour, targeting signs of fatigue and dehydration, such as puffiness, fine lines, and lack of radiance. This stick combines the hydrating action of polyglutamic acid with that of the spirodela, an aquatic plant rich in apiogalacturonanes, pectins capable of capturing and retaining water.

• The eye mask set for fine lines : This is a comprehensive treatment to smooth dehydration fine lines and brighten the eye contour in 10 minutes. The mask's effectiveness, enriched with polyglutamic acid and plant collagen, is enhanced by the second skin effect of the silicone patches. Its formula contains 99% naturally derived ingredients and the provided patches are reusable.

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• MOON-HEE SUNG & al. Promotion effects of ultra-high molecular weight poly-γ-glutamic acid on wound healing. Journal of Microbiology and Biotechnology (2015).

• RADECKA I. & al.Poly-γ-glutamic acid: production, properties and applications. Microbiology Society (2015).

• YANG S.-A. & al. Gamma polyglutamic acid (gamma-pga, h form), gamma-polyglutamate hydrogels for use as super moisturizers in cosmetic and personal care products (2019).