Effects of feeding tyrosine and phenylalanine on the accumulation of phenylethanoid glycosides to Cistanche deserticola cell suspension culture.

AIM: To investigate the effects of feeding phenylalanine (Phe) and tyrosine (Tyr) on the accumulation of total phenolic compounds and four phenylethanoid glycosides (PeGs) to a cell suspension culture of the parasitic plant Cistanche deserticola. METHOD: A cell suspension culture of C. deserticola was established and precursors of different concentrations were fed. In each group, the cell was sampled at the 24(th) day after inoculation. The content of total phenolic compounds and four PeGs compounds were determined using the Folin-Ciocalteu method and an HPLC method, respectively. RESULTS: In the Phe fed cells, the maximum PeGs yield was achieved when Phe was fed at 1.5 mmol·L(-1) and the yield reached 1.13 times the control cell concentration. In the Tyr fed cells, the maximum yield of PeGs was 1.60 times of control when 0.75 mmol·L(-1) Tyr was fed to the cells. Furthermore, it was found that the salidroside yield was 4.01 times of control group when 5 mmol·L(-1) Tyr was fed. CONCLUSION: Tyr is a better precursor for PeGs accumulation compared with Phe, and the rate limiting enzymes might be involved in the Tyr branch.