Effects of auxins and cytokinins on growth and rosmarinic acid formation in cell suspension cultures of Anchusa officinalis.

Cell suspension cultures of Anchusa officinalis required exogenous phytohormones for their normal growth. Cell lysis was observed at the third passage in a hormone-free medium. Using hormone - depleted cells, the effects of auxins (2,4-D, NAA, IAA and CFP) and cytokinins (BA, kinetin, and zeatin) on cell growth and RA production were investigated. All auxins tested could maintain growth and integrity of the cells whereas cytokinins alone could not, suggesting that this culture is auxindependent. Among the auxins tested, NAA had a pronounced effect on RA production. The total RA content obtained at optimum NAA concentration (0.25 mg/l) reached 1.7 g/l (12% of dry weight). The kinetics of growth and RA production suggested that the increase in final RA content was due to both an increase in the rate of RA synthesis and initiation of the period of synthesis in the exponential rather than the linear growth phase.