Induction of furanocoumarin biosynthesis in Glehnia littoralis cell suspension cultures by elicitor treatment.
Cell suspension cultures were established from Glehnia littoralis plants belonging to two different geographic strains. When the cells were treated with yeast extract, they started to produce and excrete furanocoumarins into the culture medium; a major component, bergapten, and a minor one, xanthotoxin, were detected and identified by HPLC and GC/MS. Changes in phenylalanine ammonia-lyase (PAL) activity and furanocoumarin production after elicitor treatment were traced, showing that PAL activity increased rapidly, reached a maximum after 24 h, and then declined to the normal level after 96 h which preceded the induced bergapten production. The induced-PAL activity of the cultured cells established from an S-type plant which accumulated trace amounts of furanocoumarins was about 50% of that in the cultured cells from an N-type plant that accumulated more than 0.1% furanocoumarins in the underground parts. However, the elicited production of bergapten was about six times higher in the cell cultures from the S-type plant. Addition of the PAL inhibitor 2-aminoindan-2-phosphoric acid (AIP) at 10 microM suppressed the induction of PAL activity and furanocoumarin production.