PRODUCTION OF BETA-DAMASCENONE PRECURSORS IN CELL-CULTURES OF VITIS-LABRUSCANA CV CONCORD GRAPES

Callus cultures of Vitis labruscana cv. Concord were initiated from bo th immature fruit and petiole tissue. Analysis revealed that the acid hydrolyzable precursors to beta-damascenone, a compound important to t he flavor of most grape species, were present in both callus types. Li ght and increased sucrose concentration were shown to raise the levels of the precursor, some of which are glycosides, in the petiole callus but not in the fruit callus. Addition of beta-carotene, a biogenic pr ecursor to beta-damascenone and its precursors and the addition of ami trole, an inhibitor of carotenoid cyclization and production, had no e ffect upon precursor levels in either tissue. Aroma compounds specific to V. labruscana grapes and other American species of grapes were not found in the callus tissue. Cell suspensions were initiated from the fruit callus and analyzed for the American character compounds as well as beta-damascenone and its acid hydrolyzable precursors. Once again, no aroma compounds specific to American species were found while beta -damascenone precursors were present at levels lower than were found i n callus on solid media and only during stationary phase of growth.