Analysis of flavonoids and phenylethanoid glycosides in the Tibetan herb Lagotis brevituba Maxim based on UHPLC-LTQ-orbitrap-MS / 药学学报

Ultra high performance liquid chromatography tandem linear ion trap orbitrap mass spectrometry (UHPLC-LTQ-orbitrap-MS) was applied to analyze and identify flavonoids and phenylethanoid glycosides in the Tibetan herb Lagotis brevituba Maxim. A method of data-dependent scan coupling with dynamic exclusion was developed for analyzing flavonoids and phenylethanoid glycosides under positive and negative ion mode of electrospray ionization (ESI). The compounds of Lagotis brevituba Maxim. were systematically identified through exact molecular mass, fragmentation patterns, retention time and reported references. A total of 167 compounds were detected, of which 84 were flavonoids and 83 were phenylethanoid glycosides, which greatly enriched the number and types of flavonoids and phenylethanol glycosides in Lagotis genus medicinal plants. Baohuoside Ⅰ, 4 disaccharide O-glycoside flavonoids (composed of deoxyhexose and glucuronic acid), 9 C-glycoside flavonoids, 15 tetrasaccharide phenylethanoid glycosides and 5 phenylethanoid glycosides with substituents on the β-position of the phenylethyl group were identified in Lagotis genus medicinal plants for the first time. This study provides scientific support for elucidating the material basis and improving the quality control of Lagotis brevituba Maxim.

Comparation of HPLC fingerprints of Lagotis integra and Lagotis brevituba between different origins / 中草药

Objective: To establish HPLC fingerprints of Lagotis integra and Lagotis brevituba which were contained in National Drug Standard and compared to Lagotis ramalana, Lagotis alutacea and Lagotis brachystachya by the established method. Methods: The similarity of HPLC fingerprints of L. integra and L. brevituba was low, so the HPLC fingerprint methods were established for both. The HPLC analysis was performed on Waters X-Bridge C18 (250 mm × 4.6 mm, 5 μm), using acetonitrile and 0.2% formic acid solution as the mobile phase at a flow rate of 1.0 mL/min, the detection wave-length was 328 nm and column temperature was 35 ℃ (L. integra) and 25 ℃ (L. brevituba). Results: There were 14 common peaks in the fingerprint of L. integra, and plantamajoside, hemiphroside B, 10-O-trans-p-methoxycinnamoyl-catalpol and 10-O-[(E)-3,4-dimethoxycinna moyl]-catalpol were standardized. There were 13 common peaks in the fingerprint of L. brevituba, and echinacoside, plantamajoside and acteoside were standardized. The similarity of HPLC fingerprint was more than 0.9 between L. integra and L. alutacea, but the others had low similarity with them. The similarity of HPLC fingerprint was more than 0.9 between L. brevituba from different batches and L. ramalana, while the others had low similarity with them. Conclusion: The established method could effectively identify L. brevituba, L. integra and L. alutacea were advised to be recorded in Medical Standards of the Ministry of Health. Lagotis ramalana could be used as a new base for "Honglian" (origin: Lagotis brevituba).

Antiproliferative Activity of Phenylpropanoids Isolated from Lagotis brevituba Maxim.

The aim of the present study was to evaluate the antiproliferative effect of phenylpropanoids isolated from the n-BuOH-soluble fraction of an ethanolic extract of Lagotis brevituba Maxim. The phenylpropanoids were identified as echinacoside, lagotioside, glucopyranosyl(1-6)martynoside, plantamoside, and verbascoside. Three of the compounds, lagotioside, glucopyranosyl(1-6)martynoside, and plantamoside, were isolated from L. brevituba for the first time. The antiproliferative activity of the isolates was evaluated in human gastric carcinoma (MGC-803), human colorectal carcinoma (HCT116), human hepatocellar carcinoma (HepG2), and human lung cancer (HCT116) cells using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Plantamoside showed promising activity against MGC-803 cells, with a half maximal inhibitory concentration value of 37.09 µM. The mechanism of the pro-apoptosis effect of plantamoside was then evaluated in MGC-803 cells. Changes in cell morphology, including disorganization of the architecture of actin microfilaments and formation of apoptotic bodies, together with cell cycle arrest in G2/M phases, were observed after treatment of plantamoside. The antiproliferative and pro-apoptotic effects were associated with a decrease in the ratio of Bcl-2/Bax and reduced mitochondrial membrane potential, which was accompanied by the release of reactive oxygen species and Ca2+ into the cytoplasm. Taken together, the results indicated that plantamoside promotes apoptosis via a mitochondria-dependent mechanism. Copyright © 2017 John Wiley & Sons, Ltd.

Chemical constituents from Lagotis brevituba / 中草药

Objective: To study the chemical constituents from Lagotis brevituba. Methods: The chemical constituents were isolated by solvent extraction, repeated silica gel chromatography, and preparative-HPLC. Their structures were elucidated by physicochemical properties and NMR data. Results: Eleven compounds were isolated from the ethyl acetate and n-butanol fraction of L. brevituba and their structures were identified as arvenin I (1), 3,4-dihydroxyphenylethanol (2), bis (2-ethylhexyl) phthalate (3), plantamajoside (4), mannitol (5), ethyl gallate (6), ethyl 3,4-dihydroxybenzoate (7), dibutyl phthalate (8), β-sitosterol (9), acteoside (10), and mussaenosidic acid (11). Conclusion: Compounds 1-3, 6, and 7 are obtained from the plants in Lagotis Gaertn. for the first time. Compounds 4 and 5 are isolated from L. brevituba for the first time.

Human stomach cancer SGC-7901 cell apoptosis induced by n-butanol extract of Lagotis Brevitaba Maxim / 中成药

AIM: To study inhibitive effect of Lagotis Brevituba Maxim extracted on human stomach cancer SGC-7901 cells proliferation and/or induce apoptosis. METHODS: Human stomach cancer SGC-7901 cells were treated with Lagotis Brevituba Maxim extracted from n-butanol of 0.34～21.60 mg/mL for 24 h～72 h.Cell proliferation was evaluated by MTT assay.Morphological changes of apoptosis were examined by fluorescence microscope and electron microscope.DNA fragmentation was visualized by agarose gel electrophoresis.The amount of apoptosis cells was measured by flow cytometry. RESULTS: Growth of SGC-7901 cells was obviously inhibited by Lagotis Brevituba Maxim extract with value from 21.60 mg/mL to 0.34 mg/mL.After incubation of SGC-7901 cells with 2.7 mg/mL Lagotis Brevituba Maxim extract for 48 h, morphological changes of apoptosis were observed.DNA ladder was identified by agarose gel electrophoresis of DNA ladder. CONCLUSION: The n-butanol extract of Lagotis Brevituba Maxim can inhibit SGC-7901 cell growth and induce apoptosis.