PGG Wrightson Limited is an agricultural supply business based in New Zealand. PGG beta-glucan An injectable formulation of the polysaccharide beta 1,3/1,6 glucan derived from the cell wall of the yeast Saccharomyces cerevisiae with potential immunomodulating and antineoplastic activities. Looking for the definition of PGG? Find out what is the full meaning of PGG on Abbreviations. PGG may refer to: Pentagalloyl glucose.