title: Identification of astilbin metabolites produced by human intestinal bacteria using UPLC-Q-TOF/MS.
abstract: Astilbin, mainly isolated from a commonly used herbal medicine, Smilax glabra Roxb (SGR), exhibits a variety of pharmacological activities and biological effects. It is metabolized by intestinal bacteria after oral administration which leads to the variation of ethnopharmacological profile of this traditional medicine. However, little is known on the interactions of this active compound with intestinal bacteria, which would be very helpful in unravelling how SGR works. In this study, different pure bacteria from human feces were isolated and were used to investigate their conversion capability of astilbin. Ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx(TM) software was used to analyze astilbin and its metabolites. The parent compound and two metabolites (quercetin and eriodictyol) were detected in the isolated bacterial samples compared with blank samples. Quercetin was present in Enterococcus sp. 8B, 8-2 and 9-2 samples. Eriodictyol was only identified in Enterococcus sp. 8B sample. The metabolic routes and metabolites of astilbin produced by the different intestinal bacteria are reported for the first time. This will be useful for the investigation of the pharmacokinetic study of astilbin in vivo and the role of different intestinal bacteria in the metabolism of natural compounds.
authors.affiliation: Jiangsu Key Laboratory for High Technology of TCM Formulae Research, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Dawei
authors.initials: D
authors.lastname: Qian
authors.forename: Jianming
authors.initials: J
authors.lastname: Guo
authors.forename: Shu
authors.initials: S
authors.lastname: Jiang
authors.forename: Er-xin
authors.initials: EX
authors.lastname: Shang
authors.forename: Jin-ao
authors.initials: JA
authors.lastname: Duan
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005243:Feces / Q000382:microbiology*; D044948:Flavonols / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*
chemical_list: D044948:Flavonols; C099069:astilbin
keywords: UPLC-Q-TOF/MS; astilbin; intestinal bacteria; metabolites