TROPANE ALKALOID PRODUCTION IN DATURA-STRAMONIUM SUSPENSION-CULTURES - ELICITOR AND PRECURSOR EFFECTS

The effects of elicitation, carbon, and nitrogen sources, and precursors on cell growth and tropane alkaloid production in Datura stramonium cell cultures were studied. D. stramonium cell cultures responded very well to elicitors in the late exponential phase. Addition of cell wall fragments of Phytophthora megasperma (Pmg) enhanced the final tropane alkaloid yield by fivefold compared with control culture. Supply of carbon and nitrogen sources, at a ratio (C/N) of up to 70, to cell cultures in the early stationary phase, suppressed tropane alkaloid production; whereas C/N ratios beyond about 100 increased the final product yield by more than 100% compared to that of the control experiment. Total alkaloid production in the cell culture supplemented with phenylalanine and ornithine was five times higher than that in the control culture. Higher ratios of tropine to tropic acid also stimulated alkaloid production. At a ratio of 20, the productivity was seven times higher than that in the control culture. Adding precursors at high concentrations (e.g., 3 to 10 mM to the cell culture reduced the final cell yield by less than 40%, while elicitation did not affect the cell yield. On the other hand, cell yield in the cultures supplemented with carbon and nitrogen sources was influenced by the C/N ratio. The highest cell yield was obtained at C/N = 70.