基于GC-IMS的白及饮片与黄花白及饮片的挥发性有机物差异研究

Study on the Difference of Volatile Organic Compounds Between Bletilla striata Decoction Pieces and Bletilla ochracea Decoction Pieces Based on GC-IMS

目的基于气相色谱-离子迁移谱(GC-IMS)技术建立白及饮片和黄花白及饮片的挥发性有机物指纹图谱,对比两者挥发性有机物的差异。方法基于GC-IMS检测白及饮片和黄花白及饮片的挥发性有机物,采用直观法和指纹图谱法对比两者挥发性有机物的差异,并对其进行定性和定量分析;借助主成分分析(PCA)和正交偏最小二乘-判别分析(OPLS-DA)方法对指纹图谱筛选出的差异峰进行分析,并结合变量重要性投影值(VIP值)和P值筛选两者的差异标志物。结果基于软件内置的NIST数据库和IMS数据库,在两种饮片中共定性出60种挥发性有机物,其以醇类、醛类、酮类为主;通过初步分析可观察到两种饮片部分挥发性有机物的峰强度存在较明显的差异,进一步通过对比指纹图谱和峰体积发现两种饮片共有65种含量差异较大的挥发性有机物,其中,白及有41种含量较高的成分,黄花白及有24种。最后结合VIP值和P值还确定了4-甲基-2-戊酮(二聚体)、樟脑(单体)、5-甲基-2-呋喃甲醇(二聚体)等12种差异标志物。结论GC-IMS技术可用于白及饮片与黄花白及饮片挥发性有机物的快速分析和对比,为后期开展两者的整体差异研究提供重要的参考。

OBJECTIVE To establish the fingerprints of volatile organic compounds(VOCs)in Bletilla striata decoction pieces and Bletilla ochracea decoction pieces based on gas chromatography-ion mobility spectrometry(GC-IMS)technology,and to compare the differences of VOCs between the two decoction pieces.METHODS The VOCs in Bletilla striata decoction pieces and Bletilla ochracea decoction pieces were detected by GC-IMS,and the differences of VOCs in the two kinds of decoction pieces were compared by two methods,the intuitive method and fingerprinting method,and at the same time,the qualitative and quantitative analysis were carried out to identify these volatile organic compounds.Principal component analysis(PCA)and orthogonal partial least squares-discriminant analysis(OPLS-DA)were used to analyze the differential peaks screened by fingerprints,and the differential marker were screened by combining the variable importance in the projection(VIP)and P-value.RESULTS Based on the built-in NIST database and IMS database in the software,a total of 60 VOCs were identified in two kinds of decoction pieces,most of which were alcohols,aldehydes,and ketones.Through preliminary analysis,it can be observed that the peak intensity of VOCs in two kinds of decoction pieces has obvious differences.Further comparison of fingerprint and peak volume shows that there are 65 kinds of VOCs whose content were quite different in the two kinds of decoction pieces,including 41 components with high contents in Bletilla striata and 24 components in Bletilla ochracea.Finally,combined with VIP and P-value,12 kinds of differential markers such as the 4-methyl-2-pentanone dimer,alcanfor monomer,5-methyl-2-furanmethanol dimer and other components were determined.CONCLUSION GC-IMS technology can be used for rapid analysis and comparison of VOCs in Bletilla striata decoction pieces and Bletilla ochracea decoction pieces,which can provide an important reference for the later study of the overall difference between Bletilla striata and Bletilla ochracea.