Post-stress metabolism involves umbelliferone production in anthocyanin-producing and non-producing cells of Glehnia littoralis suspension cultures

The effects of yeast extract on the accumulation of transcripts of phenylalanine ammonia-lyase (PAL, EC 4.1.3.5) and chalcone synthase (CHS, EC 2.3.1.74), PAL and CHS enzyme activity and furanocoumarin and anthocyanin metabolites over a 48 h period were studied in anthocyanin-producing (Violet) and non-producing (White) cell suspension cultures of Glehnia littoralis. In the course of this period, umbelliferone, which had not been detected earlier, was detected in the culture medium of the Violet as well as White cells. In White cells, the PAL transcript accumulation and an increase in PAL activity were in good agreement with the level of umbelliferone, and was followed by the induction of bergapten. In the case of the Violet cells, the accumulation of PAL and CHS transcripts, and the increases in PAL and CHS enzyme activity as well as the anthocyanin level, all of which were highly expressed in non-treated cells, were temporarily suppressed. However, the suppression of the PAL transcript and PAL activity was not as great as that of the CHS transcript accumulation and CHS activity, in which a sharp transient increase of umbelliferone production soon after elicitation appears to be a factor.