title: Simultaneous structural identification of natural products in fractions of crude extract of the rare endangered plant Anoectochilus roxburghii using H NMR/RRLC-MS parallel dynamic spectroscopy.
abstract: Nuclear magnetic resonance/liquid chromatography-mass spectroscopy parallel dynamic spectroscopy (NMR/LC-MS PDS) is a method aimed at the simultaneous structural identification of natural products in complex mixtures. In this study, the method is illustrated with respect to (1)H NMR and rapid resolution liquid chromatography-mass spectroscopy (RRLC-MS) data, acquired from the crude extract of Anoectochilus roxburghii, which was separated into a series of fractions with the concentration of constituent dynamic variation using reversed-phase preparative chromatography. Through fraction ranges and intensity changing profiles in (1)H NMR/RRLC-MS PDS spectrum, (1)H NMR and the extracted ion chromatogram (XIC) signals deriving from the same individual constituent, were correlated due to the signal amplitude co-variation resulting from the concentration variation of constituents in a series of incompletely separated fractions. 1H NMR/RRLC-MS PDS was then successfully used to identify three types of natural products, including eight flavonoids, four organic acids and p-hydroxybenzaldehyde, five of which have not previously been reported in Anoectochilus roxburghii. In addition, two groups of co-eluted compounds were successfully identified. The results prove that this approach should be of benefit in the unequivocal structural determination of a variety of classes of compounds from extremely complex mixtures, such as herbs and biological samples, which will lead to improved efficiency in the identification of new potential lead compounds.
authors: Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; E-Mails: waitgirl@imm.ac.cn (X.-X.W.); hejiuming@imm.ac.cn (J.-M.H.); rpzhang@imm.ac.cn (R.-P.Z.); hewy@imm.ac.cn (W.-Y.H.).
authors: Xiao-Xue
authors: XX
authors: Wang
authors: Jiu-Ming
authors: JM
authors: He
authors: Chun-Lan
authors: CL
authors: Wang
authors: Rui-Ping
authors: RP
authors: Zhang
authors: Wen-Yi
authors: WY
authors: He
authors: Shun-Xing
authors: SX
authors: Guo
authors: Rui-Xiang
authors: RX
authors: Sun
authors: Zeper
authors: Z
authors: Abliz
mesh_terms: D001688:Biological Products / Q000737:chemistry* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D029595:Orchidaceae / Q000737:chemistry* / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D001688:Biological Products; D010936:Plant Extracts