title: Biotransformation and metabolic profile of catalpol with human intestinal microflora by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.
abstract: Traditional Chinese medicine (TCM) has been used in clinical practice for thousands of years. Catalpol, an iridoid glucoside, abundantly found in the root of the common used herb medicine Rehmannia glutinosa Libosch, has been reported to show various biological effects and pharmacological activities. After oral administration, the active ingredient might have interactions with the intestinal bacteria, which could help unravel how the medicine was processed in vivo. In this work, different pure bacteria from healthy human feces were isolated and used to bioconvert catalpol. Ultra performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx(™) software was applied to analyze catalpol metabolites. Compared with blank samples, parent compound (M0) and four metabolites (M1-M4) were detected and tentatively identified based on the characteristics of their protonated ions. The metabolites were likely to be: catalpol aglycone (M1), acetylated catalpol (M2), dimethylated and hydroxylated catalpol aglycone (M3), nitrogen-containing catalpol aglycone (M4). M1 and M4 were generated in the majority of the samples like Bacteroides sp. 45. M3 was obtained in several bacterial samples like Enterococcus sp. 8-2 and M2 was detected only in the sample of Enterococcus sp. 43-1. To our knowledge, the metabolic routes and metabolites of catalpol produced by human intestinal bacteria were all firstly reported.
authors.affiliation: School of Pharmacy, Nantong University, Nantong 226001, PR China. Electronic address: taojinhua2000@163.com.
authors.forename: Jin-hua
authors.initials: JH
authors.lastname: Tao
authors.affiliation: Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing 210023, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.affiliation: School of Pharmacy, Nantong University, Nantong 226001, PR China.
authors.forename: Dong-geng
authors.initials: DG
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Nantong University, Nantong 226001, PR China.
authors.forename: Chi
authors.initials: C
authors.lastname: Yang
authors.affiliation: Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing 210023, PR China.
authors.forename: Le-Yue
authors.initials: LY
authors.lastname: Du
authors.affiliation: School of Pharmacy, Nantong University, Nantong 226001, PR China.
authors.forename: Wen-qian
authors.initials: WQ
authors.lastname: Qiu
authors.affiliation: Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing 210023, PR China.
authors.forename: Shu
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000328:Adult; D001439:Bacteroides / Q000378:metabolism; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004365:Drugs, Chinese Herbal / Q000032:analysis / Q000378:metabolism*; D016983:Enterococcus / Q000378:metabolism; D000069196:Gastrointestinal Microbiome; D006801:Humans; D057888:Iridoid Glucosides / Q000032:analysis / Q000378:metabolism*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D053858:Metabolic Networks and Pathways; D055442:Metabolome
chemical_list: D004365:Drugs, Chinese Herbal; D057888:Iridoid Glucosides; C078040:catalpol
keywords: Catalpol; Human intestinal bacteria; Metabolites; UPLC–Q–TOF/MS