Mori Ramulus (Chin.Ph.)-the Dried Twigs of Morus alba L./Part 1: Discovery of Two Novel Coumarin Glycosides from the Anti-Hyperuricemic Ethanol Extract

• Published in: Molecules (Basel, Switzerland) Switzerland), 2019-02, Vol.24 (3), p.629
• Main Authors: Yao, Jianbiao, He, Houhong, Xue, Jin, Wang, Jianfang, Jin, Huihui, Wu, Jian, Hu, Jiangning, Wang, Ruwei, Kuchta, Kenny
• Format: Article
• Language: English
• Subjects: Acetylcholinesterase; Allopurinol; Carbon; Chinese medicine; Coumarin; coumarin glycosides; Drug development; electrospray ionization; Ethanol; Flavonoids; Glycosides; Gout; Herbal medicine; High-performance liquid chromatography; Inflammation; Liquid chromatography; Metabolism; Morus alba; Morus alba L; Natural products; Plant extracts; Reagents; Rheumatism; Structural analysis; structural characterization; tandem mass spectrometry; Uric acid; Xanthine oxidase
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules24030629

In Traditional Chinese Medicine (TCM), Mori ramulus (Chin.Ph.)-the dried twigs of L.-is extensively used as an antirheumatic agent and also finds additional use in asthma therapy. As a pathological high xanthine oxidase (XO, EC 1.1.3.22) activity is strongly correlated to hyperuricemy and gout, standard anti-hyperuremic therapy typically involves XO inhibitors like allopurinol, which often cause adverse effects by inhibiting other enzymes involved in purine metabolism. Mori ramulus may therefore be a promissing source for the development of new antirheumatic therapeutics with less side effects. Coumarins, one of the dominant groups of bioactive constituents of , have been demonstrated to possess anti-inflammatory, antiplatelet aggregation, antitumor, and acetylcholinesterase (AChE) inhibitory activities. The combination of HPLC (DAD) and Q-TOF technique could give excellent separating and good structural characterization abilities which make it suitable to analyze complex multi-herbal extracts in TCM. The aim of this study was to develop a HPLC (DAD)/ESI-Q-TOF-MS/MS method for the identification and profiling of pharmacologically active coumarin glycosides in Mori ramulus refined extracts for used in TCM. This HPLC (DAD)/ESI-Q-TOF-MS/MS method provided a rapid and accurate method for identification of coumarin glycosides-including new natural products described here for the first time-in the crude extract of L. In the course of this project, two novel natural products moriramulosid A (umbelliferone-6-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside) and moriramulosid B (6-[[6- -(6-deoxy-α-l-mannopyranosyl)-β-d-glucopyranosyl]oxy]-2 -1-benzopyran-1-one) were newly discovered and the known natural product Scopolin was identified in L. for the first time.