The invention relates to a large scale process for the in vitro production of a cell culture of pomegranate cells, to a product prepared from such cells and to a composition comprising a complex of pholyphenols, including punicalagin, 1,2,3,4,6- pentagalloyl glucose (PGG) or both.L'invention concerne un procédé à grande échelle de production in vitro d'une culture cellulaire de cellules de grenade; un produit préparé à partir de telles cellules; et une composition comprenant un complexe de pholyphénols, notamment la punicalagine et/ou le 1,2,3,4,6-pentagalloyl glucose (PGG).