目的 为了明确内源多胺是否介导真菌诱导子诱导白桦三萜的合成。方法 将40 μg/mL真菌诱导子、1 mmol/L腐胺（Put）和2 mmol/L多胺合成抑制剂D-精氨酸（D-Arg）添加到培养8 d的白桦悬浮培养体系中，利用高效液相色谱和比色法分析多胺量和三萜量。采用药理学和恢复实验分析多胺在真菌诱导子诱导白桦三萜合成中的作用。结果 真菌诱导子或Put处理后，白桦悬浮细胞中的多胺量、三萜量和产量均呈增加趋势，其中处理24 h时，三萜量达最大值，分别增加了68.54%和30.34%。真菌诱导子和Put共同处理虽提高了三萜量，但其产量却低于真菌诱导子单独处理。真菌诱导子和D-Arg共同处理后三萜量低于真菌诱导子单独处理，处理24 h时降低程度最高，为40.57%。恢复实验发现，随着恢复时间的延长，真菌诱导子、Put以及真菌诱导子与D-Arg对白桦三萜合成的影响效应逐渐减弱，恢复到对照水平。结论 多胺介导了真菌诱导子促进白桦悬浮细胞中三萜的合成。
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 mM), and D-arginine (D-Arg, 2 mM) were added to the eight-day-old suspension cell culture, the changes of triterpenoid content and free polyamines content (free Put, Spm and Spd) were analyzed by chemical colorimetry and HPLC. The effect of polyamine on the triterpenoid synthesis in birch (Betula 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. Comparing 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 level of the control finally. Conclusion From the above results, we conclude that polyamine could mediate the synthesis of triterpenoid in cells of B. platyphylla induced by fungal elicitor.