PSORALEN AND OTHER LINEAR FURANOCOUMARINS AS PHYTOALEXINS IN GLEHNIA-LITTORALIS

Inoculation of Glehnia littoralis root slices with Pseudomonas cichori i induced the production of four linear furanocoumarin phytoalexins, p soralen, xanthotoxin, bergapten and demethylsuberosin, of which the fo rmer three have been reported as constituents of the crude drug Glehni a root. A time-course study on the respective P. cichorri-inoculated, UV-irradiated and non-irradiated root slices showed greatly increasing concentrations of the furanocoumarins after stress treatment. Psorale n, xanthotoxin and bergapten in the crude drug were considered, at-lea st in part, to be stress metabolites produced during processing. (C) 1 997 Elsevier Science Ltd.