Accumulation of anthocyanins enhanced by a high osmotic potential in grape (Vitis vinifera L.) cell suspensions.

A cell suspension of grape, Vitis vinifera L. cv Gamay Fréaux, was grown under different conditions of water stress (high external osmotic potential) induced by an increase of sucrose concentration or by the addition of mannitol to the culture medium. Best growth (cell density) was achieved in the low osmotic potential medium. Increasing the osmotic potential of the medium from -0.5 MPa to -0.9 MPa medium resulted in a significant increase in accumulation of anthocyanins in pigmented cells. Regulation of the osmotic potential of culture medium may be useful in controlling anthocyanin production.