Cell growth and carotenoid synthesis in cultured carrot cells were examined in media with different phosphate concentrations. The growth was accelerated by increasing the P concentration and the rate of growth in the logarithmic phase was dependent on the initial concentration of phosphate. The maximum yield of the culture at the stationary phase was obtained when the additional phosphate was supplied to the culture at late logarithmic phase. Carotenoid accumulation was closely correlated to the cell growth and enhanced in P-rich medium.
