Hyaluronic acid, also called hyaluronan, is an anionic, nonsulfated glycosaminoglycan distributed widely throughout connective, epithelial, and neural tissues. It is unique among glycosaminoglycans in that it is nonsulfated, forms in the plasma membrane instead of the Golgi apparatus, and can be very large: human synovial HA averages about 7 million Da per molecule, or about 20000 disaccharide monomers, while other sources mention 3–4 million Da. As one of the chief components of the extracellular matrix, hyaluronan contributes significantly to cell proliferation and migration, and may also be involved in the progression of some malignant tumors. The average 70 kg person has roughly 15 grams of hyaluronan in the body, one-third of which is turned over every day. Hyaluronic acid is also a component of the group A streptococcal extracellular capsule, and is believed to play a role in virulence.
Cleans or protect skin, heal skin infections or acne, act as an anti-bacterial and anti-inflammatory, absorb dirt, oil, and toxins.