Pentagalloyl glucose can precipitate proteins including human salivary α-amylase.
It may also be used in radioprotection.
The enzyme beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase uses 1-O-galloyl-beta-D-glucose and 1,2,3,6-tetrakis-O-galloyl-beta-D-glucose to produce D-glucose and pentagalloyl glucose.
Metabolism of ellagitannins
β-glucogallin: 1,2,3,4,6-pentagalloyl-β-d-glucose galloyltransferase is an enzyme found in the leaves of Rhus typhina that catalyzes the galloylation of 1,2,3,4,6-penta-O-galloyl-β-D-glucose to 3-O-digalloyl-1,2,4,6-tetra-O-galloyl-β-d-glucose (hexa-galloylglucose).
Pentagalloyl glucose can undergo oxidation reactions which are depending on the pH.