Propyl Gallate is a trihydroxybenzoic acid found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants.
Propyl Gallate is found both free and as part of hydrolyzable tannins. The gallic acid groups are usually bonded to form dimers such as ellagic acid. Hydrolysable tannins break down on hydrolysis to give gallic acid and glucose or ellagic acid and glucose, known as gallotannins and ellagitannins respectively.

Function:
Propyl gallate has been reported to be an effective antioxidant-based hepatoprotector, both in vitro and in vivo. It has also been shown to prevent neuronal apoptosis and block the death of neurons exposed to FeSO 4 /GA as well as partially protect endothelial cells against TNF-induced apoptosis.

Application Area:
Propyl gallate is used to protect oils and fats in products from oxidation.
Propyl gallate is used in foods, cosmetics, hair products, adhesives, and lubricants.
Propyl gallate is used as a triplet state quencher and an antioxidant in fluorescence microscopy.