Pigment synthesis by immobilized cultured cells of lavandula vera and characterization of a component of the pigments

Immobilized cultured cells of Lavandula vera accumulated blue pigments in the culture medium in the presence of L-cysteine when the cells were cultivated under illumination, while brown pigments were accumulated in the dark. Several components of the brown pigments turned blue spontaneously on incubation in the culture medium without the plant cells, Fe³⁺ ion being found to play an important role in this conversion. One of the main components of the brown pigments, which is a precursor of the blue pigments, was deduced to be a novel compound, 1-methylethyl 3,4-dihydro-7,8-dihydroxy-5-methoxy-3,10-dimethyl-4-oxo-4H-naphtho[2,3-b]pyran-3-butanoate.