LCMS-IT-TOF法快速鉴定库拉索芦荟中的化学成分

目的：快速分析库拉索芦荟中的化学成分，并比较这些化学成分在市售库拉索芦荟药材与新鲜库拉索芦荟黄汁中组成和含量的异同。方法：应用优化的高效液相色谱-离子阱-飞行时间质谱法（LCMS-IT-TOF）对市售库拉索芦荟药材及新鲜库拉索芦荟叶黄汁进行分析，色谱柱为Aglient TC-C18柱（4.6 mm×250 mm，5 μm），以水（A）-甲醇（B）进行梯度洗脱，质谱的离子源为电喷雾离子源，同时采用正负离子检测模式，获得各组分多级质谱数据。结果：库拉索芦荟中色酮、吡喃酮、萘环、蒽醌和蒽酮类化学成分得到较好地分离与检测，利用质谱裂解规律和文献数据，鉴定了其中30种化学成分，对库拉索芦荟中的各类成分的质谱裂解规律进行了解析。结论：新鲜库拉索芦荟叶黄汁中的化学成分与市售库拉索芦荟药材中的化学成分的种类及含量有较大差异，前者以异芦荟色苷D及芦荟苷为主要成分，芦荟苦素含量较低；后者以芦荟苦素及芦荟苷为主要成分，芦荟苦素的含量最高。LCMS-IT-TOF分析可以获得库拉索芦荟中各类化合物丰富的结构信息，为库拉索芦荟化学成分的鉴定与分析提供了一种快速有效的方法，也为库拉索芦荟药材的质量控制、品质评价和开发利用提供更多科学依据。

Rapid Identification of Chemical Composition in Aloe Barbadensis Mill by Liquid Chromatography-Mass Spectrometry-Ion Trap-Time-of-Flight

This article was aimed to rapidly analyze chemical composition in Aloe Barbadensis Mill, and to compare the chemical composition of commercial aloe vera medicinal materials with that of fresh aloe yellow exudate. An optimized liquid chromatography-mass spectrometry-ion trap-time-of-flight (LCMS-IT-TOF) method was applied for the analysis of commercial aloe vera medicinal materials and fresh aloe yellow exudates. The Agilent TC-C18 column (4.6 ×250 mm, 5 m) was used. The gradient elution was a solvent system of water(A)-methanol(B). ESI source was operated in both positive and negative ion modes. The results showed that chromones, pyrones, naphthalene derivative, anthrones and anthraquinones were separated successfully, 30 compounds were characterized by the comparison of characteristic MS/MS fragment ions data with the literature. The diagnostic fragmentation patterns of different chemical compositions were also discussed on the basis of EST-IT-TOF MS data. It was concluded that the chemical composition of commercial aloe vera medicinal materials were significantly different from that of fresh aloe yellow exudate in terms of types and contents: the former one mainly contains isoaloeresin D and aloin, and few aloesin; but the latter is mainly composed of aloesin and aloin, and the content of aloesin is the highest. The LCMS-IT-TOF analysis can be used to rapidly obtain rich structural information of different chemical compositions, which improves the efficiency of qualitative analysis of chemical composition, and is of great significance to the quality control, evaluation and the utilization of Aloe Barbadensis Mill.