Poly-γ-Glutamic Acid: A Green Alternative to Sodium Polyacrylate for Superabsorbents

C. Peng
Ecovia Renewables Inc.,
United States

Keywords: poly-γ-glutamic acid, superabsorbents, bio-based materials


Poly-γ-glutamic acid (γ-PGA) is a water-soluble polymeric polycarboxylic acid that is commercially manufactured by a microbial fermentation process and has a wide number of potential applications ranging from food, hygiene and agriculture to water treatment. γ-PGA is renewable, biodegradable, and non-toxic; it has potential as a sustainable alternative to polyacrylates that are widely used as personal care ingredients and as superabsorbent polymers. However, one of the main challenges for γ-PGA application is its high price. This is due to costly nutrient requirements for Bacillus fermentation, high purification costs and a lack of cost-effective chemistries to prepare γ-PGA derivatives. Ecovia Renewables Inc. is commercializing a novel fermentation platform to cost-effectively produce γ-PGA using low-cost feedstocks. γ-PGA produced from our process has been demonstrated to have comparable functionality with sodium polyacrylate. For example, it can be derivatized into superabsorbent polymers (AzuraGelTM; USDA certified biobased product) that absorb up to 300x their weight in water and show improved absorption under load (AUL) over other biobased superabsorbents such as starch-based polymers. In this presentation, the application areas and the benefits of γ-PGA derivatives will be discussed.