Extraction,Isolation And Identification Of Flavonoid Glycoside And Glucuronidc From Copper Tolerant Plant Elsholtzia Splendens

Elsholtzia splendens Nakai, belonging to Lamiaceae family, is an important Chinese native copper indicator during copper ore exploration. Copper is one of the important elements of plant photosynthesis. Plants regulate mechanism, such as copper protein, using copper to satisfy their normal physiological needs, also promote the synthesis of secondary metabolites polyphenols, for the dynamic balance of oxygen free radicals and copper requirements within plants.In this study, we focused on the n-BuOH extracts from the flowering aerial biomass (stems, flowers and leaves) of copper tolerant plant E. splendens, then the extraction, separation and identification of important flavonoid glycosides were performed, and the main results were presented as follows:(1) The methods for separating flavonoid glycoside compounds were established from Elsholtzia plants. In a ratio of 1/17, the ground powders of E. splendens flowering aerial biomass were treated with 60% ethanol-H2O, the obtained crude extract was successively partitioned between H2O and petroleum ether, EtOAc and H2O-saturated n-BuOH, yielding the n-BuOH Deep-brown Extract with the yield of 7.2%. Among these extracts, the n-BuOH Extract accumulate more flavonoid glycosides compounds of larger polarity. Column chromatography (CC) separation were performed on the n-BuOH Extract, using D101 macroporous resin and SephadexTM LH-20 gel, in combination with thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) to determine the target compounds of interest which were further purified by polyamide resin (PR) and preparative HPLC. The CC separation led to the isolation of four flavonoid glycosides compounds, with the purity higher than 98%.(2) The structures of flavonoid glycosides monomer compounds were chemically identified. The spectral techniques were employed by the use of ultraviolet (UV), infrared spectroscopy (FTIR), electrospray ionization mass spectrometry (ESI/MS), one and two-dimensional nuclear magnetic resonance (1H NMR,13C NMR, HMBC and NOSEY), then three flavonoid glycoside compounds were chemically elucidated as Nepetin-7-O-β-D-glucoside, Hispidulin-7-O-β-D-glucoside and Apigenin-7-O-β-D-glucoside, respectively, as well as one flavonoid glucuroniode. Among these, Nepetin-7-O-β-D-glucoside, Hispidulin-7-O-β-D-glucoside and flavonoid glucuroniode were first isolated from E. splendens plants.