Hyaluronic acid is a mucopolysaccharide that is an important component of human connective tissue, acting as a binding and protective agent. It is also found in synovial fluid, which lubricates and cushions the joints, and in the aqueous humour of the eye.
Hyaluronic acid is produced naturally in the human body. It is synthesised by an enzyme called hyaluronic acid synthase. This enzyme facilitates the joining of two sugars, D-glucuronic acid and N-acetyl glucosamine, which are then transformed into hyaluronic acid.
Hyaluronic acid is also sold as a nutritional supplement. The source of hylauronic acid is considered to be natural if it is extracted from an animal source with no further synthesis of the molecule. Natural hyaluronic acid is obtained from rooster combs or from the aqueous humours of the eyes of cows.
Artifical sources of hyaluronic acid are synthesised in a laboratory using other chemicals as raw materials. This process is called biosynthesis. The streptococcus strain of bacteria are utilised to synthesise hyaluronic acid.