... USA for 6 years. Gallic acid is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4, ... 5-trihydroxybenzoic acid, found in gallnuts, sumac, ... cancer cells, without harming healthy cells. Gallic acid is used as a remote astringent in cases of internal haemorrhage. Gallic ...