Polyglutamic acid is an ingredient that offers a very broad spectrum of action.
First of all, it is a moisturizing active ingredient. Hyaluronic acid, contained in the extracellular matrix, is naturally degraded over time. Polyglutamic acid inhibits the enzymes responsible for this phenomenon , which maximizes hydration of the epidermis. In addition, it stimulates the synthesis of natural hydration factors, responsible for the water retention capacity of the hydrolipidic film, which boosts its water absorption capacity . Finally, polyglutamic acid forms a gel on the surface of the cells capable of retaining five thousand times its weight in water. Thus the water that would have left the skin by trans-epidermal evaporation is retained in the gel, and can be returned throughout the day .
 Characterization of poly(L-glutamic acid)-grafted hyaluronan as a novel candidate medicine and biomedical device for intra-articular injection. Kazuaki Muramatsu, Yuya Tajima, Rin Kaneko, Yuta Yanagita, Hiroyuki Hirai, Nana Hiura First published: 04 July 2017
 Ishwar Bajaj, Rekha Singhal, Poly (glutamic acid) – An emerging biopolymer of commercial interest, Bioresource Technology, Volume 102, Issue 10, 2011.
 Lee NR, Go TH, Lee SM, Jeong SY, Park GT, Hong CO, Son HJ. In vitro evaluation of new functional properties of poly-γ-glutamic acid produced by Bacillus subtilis D7. Saudi J Biol Sci. 2014 Apr;21