Components research on Tetrastigma hemsleyanum Diels et Gilg: Identification and effect of drying methods on the content of ten main constituents by targeting metabolomics method.

Tetrastigma hemsleyanum Diels et Gilg (TH) is one of the new eight Genuine Medicinal Materials of Zhejiang. It has extensive biological activities, such as anti-inflammatory, anti-tumor and analgesic activities, etc. In this study, the chemical components of TH were systematically investigated by ultra high-performance liquid chromatography-tandem quadrupole time of flight mass spectrometry (UPLC/Q-TOF-MS). Based on the MS spectrum, 39 compounds in TH extracts including 14 flavonoids, 10 fatty acids, 5 polyphenols and phenolic acids, 4 terpenes and other compounds were detected and tentatively identified. TH samples were treated under different drying methods (vacuum freeze drying, hot air drying, natural drying, light drying and vacuum drying). Besides, the effect of different drying methods on the content of 10 main chemical constituents in TH extracts including catechin, rutin, kaempferol-3-O-rutinoside and so on was also investigated by targeting metabolomics method with ultra high-performance liquid chromatography-tandem triple quadrupole mass spectrometry (UPLC-MS/MS) assisted by multivariate statistical analysis. Large differences were observed between vacuum drying and vacuum freeze drying with remarkable content changes. The contents of rutin, proanthocyanidin B1 and catechin were the most different among the various drying methods. The systematic identification of chemical constituents is helpful for the further medicinal development and application of TH. The effects of drying methods on the content of TH components were studied, which provided experimental data for the processing, storage and quality control of TH.