RESUMO
Objective: To analyze the effect of exogenous putrescine on triterpenoid accumulation and sucrose metabolism. Methods: Putrescines (0.1, 1, and 5 mmol/L) were added to the eight-day-old suspension cell culture, and the content changes of sucrose, fructose, glucose, and triterpenoid, the activity of sucrose phosphate synthase (SPS) and sucrose synthase (SS) were analyzed by colorimetry. Results: Putrescine increased the content of sucrose in cells but decreased the conent in culture medium. Among them, the content of sucrose was most enhanced after putrescine induction for 6 h; The increasing rate was 169.41%. However, the contents of fructose and glucose were only increased in 6 h under the putrescine treatment, the other treatments decreased the contents of fructose and glucose. In addition to 5 mmol/L putrescine treatment, putrescine enhanced the activities of SPS and SS. The content of triterpenoid in suspension cells was increased in 12 h after 5-40 g/L sucrose induction, and the content of triterpenoid was most induced by 20 g/L sucrose, the increasing rate was 52.16%. In addition to increasing 27.37% on triterpenoid content in cells treated by 1 mmol/L putrescine and 5 g/L sucrose, the treatment of 1 mmol/L putrescine and other sucrose concentration decreases the accumulation of triterpenoid. Conclusion: Putrescine could increase the sucrose content and triterpenoid accumulation in suspension cell culture, and we preliminarily inferred that the induction of sucrose by putrescine could participate in the accumulation of triterpenoid in birch cells.
RESUMO
Objective: To clarify whether polyamine-mediated triterpenoid synthesis in birch (Betula platyphylla) suspension cells induced by fungal elicitor. Methods: Fungal elicitor (40 μg/mL), putrescine (Put, 1 mmol/L), and D-arginine (D-Arg, 2 mmol/L) were added to the eight-day-old suspension cell culture, the content changes of triterpenoid and free polyamines were analyzed by chemical colorimetry and HPLC. The effect of polyamine on triterpenoid synthesis in B. platyphylla suspension cells induced by fungal elicitor was analyzed by pharmacology and restoration experiment. Results: After the treatment of fungal elicitor or Put, the contents and yields of free polyamines and triterpenoid were increased. Among of them, the triterpenoid content was the highest after 24 h treatment, the increasing rates were 68.54% and 30.34%, respectively. The triterpenoid content was increased by the cotreatment of fungal elicitor and Put, but the increasing degree of yield was lower than that by the treatment of fungal elicitor alone. Compared with the fungal elicitor alone, the cotreatment of fungal elicitor and D-Arg decreased the triterpenoid content by 40.57% in the highest degree of decreasing after 24 h treatment. In restoration experiment, with the treatment time prolonging, the effect of fungal elicitor, Put, or cotreatment of fungal elicitor and D-Arg on triterpenoid synthesis was decreasing to the control level finally. Conclusion: Polyamine could mediate the triterpenoid synthesis in cells of B. platyphylla induced by fungal elicitor.