Differentiation of various kinds of Fructus schisandrae by surface desorption atmospheric pressure chemical ionization mass spectrometry combined with principal component analysis

Various kinds of Fructus schisandrae were studied by surface desorption atmospheric pressure chemical ionization mass spectrometry (DAPCI-MS) without any sample pretreatment. The volatile components in F. schisandrae were detected in the ambient environment and the analytical time for each sample was only 30 s. F. schisandrae are produced mainly in 5 different geographical regions (Elunchun, Mudanjiang, Tonghua, Tieling and Shangluo), and they could be successfully differentiated according to their chemical markers by Principal Component Analysis (PCA). A total of 8 components which gave more contribution for PCA analysis were unambiguously identified by comparison of the MS² data of chemical markers to the data of reference compounds as reported in the literature. Similarly, wild grown and cultivatable species of F. schisandrae were well separated by the above-mentioned method. In addition, raw and processed cultivatable F. schisandrae (steamed by water, alcohol, vinegar, or honey, and fried by honey) were found to be clustered at different location, respectively. Furthermore, the clustered degree of differently processed products was correlated with their clinical effects. Our results demonstrated that DAPCI-MS in combination with PCA was a feasible technique for high-throughput differentiation of various kinds of F. schisandrae. It is also possible that DAPCI-MS could become a powerful technology in the studies of traditional Chinese medicine studies and in situ analysis of Chinese herbs.