瑞香狼毒根中活性物质的分离鉴定及作用机理

以瑞香狼毒根为研究材料,模式植物拟南芥为受体,采用实验室活体生物实验方法研究了瑞香狼毒根提取物及不同极性溶剂萃取物对7 d龄拟南芥幼苗的生长抑制作用;采用活性跟踪的化合物分离方法,分析了其中的活性化合物成分,并通过拟南芥DR5-GUS转基因株系,研究了单体化合物对拟南芥生长发育及根系生长素分布的影响.结果显示,瑞香狼毒根乙醇提取物对拟南芥有很强的生长抑制作用,其乙酸乙酯和氯仿萃取物的抑制活性最为显著,从氯仿萃取物中分离得到两种香豆素类化合物伞形花内酯(1)和西瑞香素(2),其中化合物1能够显著抑制拟南芥幼苗生长及根系发育,且明显降低了根部内源生长素的分布水平;化合物2也有较为明显的抑制活性.研究表明,氯仿和乙酸乙酯萃取物是瑞香狼毒植物毒活性的主要有效部位;伞形花内酯(1)和西瑞香素(2)是瑞香狼毒植物毒活性的有效成分,化合物1对拟南芥生长发育的抑制作用与生长素途径密切相关.

Isolation of Plant Growth Inhibitory Components from the Root of Stellera chamaejasme and Function Mechanism

The inhibitory effects of the root extract and fractions prepared with different solvents from Stellera chamaejasme on 7-day-old Arabidopsis thaliana seedlings were tested and compared by living-bioassay methods.A bioactivity-driven fractionation was conducted to analyze the active chemical constituents of the root extract and the effect of the purified compounds on the endogenous auxin levels was researched by A.thaliana DR5-GUS transgenic line.Results showed that the ethanol extract and its chloroform and ethylacetate fractions have significant phytotoxic effect.Two coumarins umbelliferone(1) and daphnoretin(2) were isolated from the chloroform fraction.Compound 1 significantly inhibited the growth of A.thaliana seedlings and greatly reduced the accumulation levels of the endogenous auxin at root tips.Compound 2 also showed inhibitory activity.Our research indicated that the chloroform and ethylacetate extracts were the main effective phytotoxic fractions of S.chamaejasme.Umbelliferone(1) and daphnoretin(2) were the effective phytotoxic compounds,and umbelliferone’s inhibitory effect correlated to auxin pathway.