Elicitation and in situ adsorption enhanced secondary metabolites production of Tripterygium wilfordii Hook. f. adventitious root fragment liquid cultures in shake flask and a modified bubble column bioreactor

The experiments of elicitation and in situ adsorption were conducted in shake flasks and then tested in a modified bubble column bioreactor for enhancing the productions of three active metabolites in Tripterygium wilfordii Hook. f., triptolide, wilforgine and wilforine. Methyl jasmonate was screened out as the elicitor and the non-ionic polymeric ion-exchange resin of Amberlite^® XAD-7 was used for in situ product removal and protecting the alkaloids from degradation in the medium. In shake flask experiments, 3.55-fold, 49.11-fold, and 10.40-fold of triptolide, wilforgine, and wilforine, respectively, could be recovered from the medium and XAD-7 resin by elicitation and in situ product removal, compared with the control. The modified 10 L bubble column bioreactor had similar productions of the three active metabolites but needed a further optimization of parameters for better growth of adventitious roots.