知母、麦冬和薯蓣中螺甾体皂苷的质谱裂解规律研究

摘要

目的:运用超高效液相色谱-串联质谱(UPLC-MS/MS)方法研究知母、麦冬和薯蓣中螺甾烷醇型甾体皂苷的[M +NH4]+离子质谱裂解行为.方法:采用电喷雾离子源,在阳离子模式下运用低、中、高不同碰撞能,研究5种螺甾烷醇型甾体皂苷质谱裂解规律.结果:总结了5种螺甾烷醇型甾体皂苷氨化离子的质谱裂解行为,其特征为螺甾烷醇型甾体皂苷首先失去17 Da,然后由外端至内端依次中性失去C-3上的各个糖基,生成特征性的[苷元+H]+离子,最后[苷元+H]+离子E环断裂脱去相应侧链和水分子.结论:阐明了螺甾烷醇型甾体皂苷质谱裂解行为,该研究将有助于知母、麦冬和薯蓣相关甾体皂苷类化合物的结构解析.%Objective:To analyze the fragmentation patterns of spirostanol steroidal saponins with UPLC-MS/MS in Anemarrhena asphodeloides Bge,Ophiopogon japonicus and Dioscorea opposita Thunb.Methods:Five kinds of spirostanol steroidal saponins were investigated with ESI + under low,middle and high collision energy.Results:The characteristic fragmentation patterns of five spirostanol steroidal saponins were summarized in positive mode,it was found that the spirostanol steroidal saponins firstly lost C-3 sugar groups,then characteristic aglycone ions were obtained by the cleavage of the E-ring and H2O.Conclusion:Characteristic fragmentation patterns of the spirostanol steroidal saponins could be significant to analyze other steroidal saponins.