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Ping Li - One of the best experts on this subject based on the ideXlab platform.
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structural characterization and identification of Iridoid glycosides saponins phenolic acids and flavonoids in flos lonicerae japonicae by a fast liquid chromatography method with diode array detection and time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Lianwen Qi, Chunyun Chen, Ping LiAbstract:A fast liquid chromatography method with diode-array detection (DAD) and time-of-flight mass spectrometry (TOF-MS) has been developed for analysis of constituents in Flos Lonicerae Japonicae (FLJ), a traditional Chinese medicine derived from the flower bud of Lonicerajaponica. The chromatographic analytical time decreased to 25 min without sacrificing resolution using a column packed with 1.8-µm porous particles (4.6 × 50 mm), three times faster than the performance of conventional 5.0-µm columns (4.6 × 150 mm). Four major groups of compounds previously isolated from FLJ were structurally characterized by DAD-TOF-MS: Iridoid glycosides showed maximum UV absorption at 240 nm; phenolic acids at 217, 242, and 326 nm; flavonoids at 255 and 355 nm; while saponins had no absorption. In electrospray ionization (ESI)-TOF-MS experiments, elimination of a glucose unit (162 Da), and successive losses of H2O, CH3OH and CO, were generally observed in Iridoid glycosides; saponins were characterized by a series of identical aglycone ions; phenolic acids typically generated a base peak at [M–H–caffeoyl]− by loss of a caffeic acid unit (162 Da) and several marked quinic acid moiety ions; cleavage of the glycosidic bond (loss of 162 or 308 Da), subsequent losses of H2O, CO, RDA and C-ring fragmentation were the most possible fragmentation pathways for flavonoids. By accurate mass measurements within 4 ppm error for each molecular ion and subsequent fragment ions, as well as the ‘full mass spectral’ information of TOF-MS, a total of 41 compounds including 13 Iridoid glycosides, 11 phenolic acids, 7 saponins, and 10 flavonoids were identified in a methanolic extract of FLJ. Copyright © 2009 John Wiley & Sons, Ltd.
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qualitative and quantitative analysis of Iridoid glycosides in the flower buds of lonicera species by capillary high performance liquid chromatography coupled with mass spectrometric detector
Analytica Chimica Acta, 2006Co-Authors: Yue Song, Menghua Wu, Songlin Li, Huijun Li, Ping LiAbstract:Abstract A highly sensitive and specific method, based on capillary high performances liquid chromatography coupled with single quadrupole mass spectrometry using electrospray ionization (capillary HPLC–ESI/MS), is proposed for the identification and quantification of Iridoid glycosides in the flower buds of five Lonicera species. A Zorbax SB-C18 (0.3 mm × 150 mm, 5 μm) capillary column and a gradient elution with methanol–acetonitrile–aqueous acetate acid were utilized. The most intensive electrospray ionisation signals were found in the negative ion spectra owing to CH 3 COO − adducts. Eight Iridoid glycosides derived from the flower buds of Lonicera species were analyzed by mass spectrometry: sweroside (IG1), 7- O -ethyl sweroside (IG2), 7-epi vogeloside (IG3), secoxyloganin (IG4), secoxyloganin 7-butyl ester (IG5), dimethyl-secologanoside (IG6), centauroside (IG7), and loganin (IG8) using combined information on retention time, the molecular ion mass and fragment ion masses. Detection limits were lower than 1.9 ng/mL in selected ion monitoring (SIM) mode and all calibration curves showed good linear regression ( r 2 > 0.9938) within test ranges. The validated method was successfully applied to analyze eight Iridoid glycosides in the flower buds of five Lonicera species and provided a new basis of assessment on quality of Flos Lonicerae.
Chunyun Chen - One of the best experts on this subject based on the ideXlab platform.
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structural characterization and identification of Iridoid glycosides saponins phenolic acids and flavonoids in flos lonicerae japonicae by a fast liquid chromatography method with diode array detection and time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Chunyun ChenAbstract:A fast liquid chromatography method with diode-array detection (DAD) and time-of-flight mass spectrometry (TOF-MS) has been developed for analysis of constituents in Flos Lonicerae Japonicae (FLJ), a traditional Chinese medicine derived from the flower bud of Lonicera japonica. The chromatographic analytical time decreased to 25 min without sacrificing resolution using a column packed with 1.8-microm porous particles (4.6 x 50 mm), three times faster than the performance of conventional 5.0-microm columns (4.6 x 150 mm). Four major groups of compounds previously isolated from FLJ were structurally characterized by DAD-TOF-MS: Iridoid glycosides showed maximum UV absorption at 240 nm; phenolic acids at 217, 242, and 326 nm; flavonoids at 255 and 355 nm; while saponins had no absorption. In electrospray ionization (ESI)-TOF-MS experiments, elimination of a glucose unit (162 Da), and successive losses of H(2)O, CH(3)OH and CO, were generally observed in Iridoid glycosides; saponins were characterized by a series of identical aglycone ions; phenolic acids typically generated a base peak at [M-H-caffeoyl](-) by loss of a caffeic acid unit (162 Da) and several marked quinic acid moiety ions; cleavage of the glycosidic bond (loss of 162 or 308 Da), subsequent losses of H(2)O, CO, RDA and C-ring fragmentation were the most possible fragmentation pathways for flavonoids. By accurate mass measurements within 4 ppm error for each molecular ion and subsequent fragment ions, as well as the 'full mass spectral' information of TOF-MS, a total of 41 compounds including 13 Iridoid glycosides, 11 phenolic acids, 7 saponins, and 10 flavonoids were identified in a methanolic extract of FLJ.
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structural characterization and identification of Iridoid glycosides saponins phenolic acids and flavonoids in flos lonicerae japonicae by a fast liquid chromatography method with diode array detection and time of flight mass spectrometry
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Lianwen Qi, Chunyun Chen, Ping LiAbstract:A fast liquid chromatography method with diode-array detection (DAD) and time-of-flight mass spectrometry (TOF-MS) has been developed for analysis of constituents in Flos Lonicerae Japonicae (FLJ), a traditional Chinese medicine derived from the flower bud of Lonicerajaponica. The chromatographic analytical time decreased to 25 min without sacrificing resolution using a column packed with 1.8-µm porous particles (4.6 × 50 mm), three times faster than the performance of conventional 5.0-µm columns (4.6 × 150 mm). Four major groups of compounds previously isolated from FLJ were structurally characterized by DAD-TOF-MS: Iridoid glycosides showed maximum UV absorption at 240 nm; phenolic acids at 217, 242, and 326 nm; flavonoids at 255 and 355 nm; while saponins had no absorption. In electrospray ionization (ESI)-TOF-MS experiments, elimination of a glucose unit (162 Da), and successive losses of H2O, CH3OH and CO, were generally observed in Iridoid glycosides; saponins were characterized by a series of identical aglycone ions; phenolic acids typically generated a base peak at [M–H–caffeoyl]− by loss of a caffeic acid unit (162 Da) and several marked quinic acid moiety ions; cleavage of the glycosidic bond (loss of 162 or 308 Da), subsequent losses of H2O, CO, RDA and C-ring fragmentation were the most possible fragmentation pathways for flavonoids. By accurate mass measurements within 4 ppm error for each molecular ion and subsequent fragment ions, as well as the ‘full mass spectral’ information of TOF-MS, a total of 41 compounds including 13 Iridoid glycosides, 11 phenolic acids, 7 saponins, and 10 flavonoids were identified in a methanolic extract of FLJ. Copyright © 2009 John Wiley & Sons, Ltd.
Xiao Wang - One of the best experts on this subject based on the ideXlab platform.
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water compatible micron sized monodisperse molecularly imprinted beads for selective extraction of five Iridoid glycosides from cornus officinalis fructus
Journal of Chromatography A, 2017Co-Authors: Wenhua Ji, Yanling Geng, Xiao WangAbstract:Abstract An efficient, accurate and sensitive method for the determination of five Iridoid glycosides (IGs) in Cornus officinalis fructus using molecularly imprinted solid phase extraction (MISPE) coupled with high performance liquid chromatography (HPLC) has been developed. Water-compatible molecularly imprinted beads (MIBs) were synthesized by precipitation polymerization, using alkenyl glycosides glucose as the hydrophilic functional monomer. Scanning electron microscopy showed that the MIBs had a narrow particle size distribution, with diameters in the range 7.5–9.3 μm. The special molecular recognition by the MIBs of IGs in aqueous media was verified by static adsorption, kinetic adsorption, and selectivity experiments. The newly prepared MIBs were used as sorbents in solid phase extraction (SPE) for the selective recognition of five IGs (loganin, morroniside, loganic acid, 7- O -ethyl-morroniside and 7- O -methyl morroniside) in Cornus officinalis fructus. When optimized, the MISPE-HPLC method had good linearity (0.02–100 mg g −1 ), with correlation coefficient ( R ) ≥ 0.994. Recoveries at three spiked levels were in the range 80.0%–94.0%. Because of its excellent specificity and hydrophilicity, SPE based on monodisperse MIBs provides a promising pretreatment strategy for the analysis of active components in natural products, especially for the quality control of traditional Chinese medicines.
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development of hydrophilic magnetic molecularly imprinted polymers by directly coating onto fe3o4 with a water miscible functional monomer and application in a solid phase extraction procedure for Iridoid glycosides
RSC Advances, 2016Co-Authors: Mingming Zhang, Xiao Wang, Wei Liu, Xingmin Wang, Wenjuan Duan, Hongkai XieAbstract:Hydrophilic magnetic molecularly imprinted polymers (HMMIPs) have been synthesized by directly coating onto Fe3O4 alkenyl glycosides glucose as a novel water-miscible functional monomer, which introduces an abundance of hydrophilic groups into polymers. Photographs of the dispersion properties and water contact angles demonstrated that these HMMIPs have excellent hydrophilicity compared with those prepared using the traditional hydrophilic functional monomer, methacrylic acid. HMMIPs were characterized by Fourier transform infrared spectroscopy, vibrating sample magnetometry, transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. Binding experiments indicated that HMMIPs had an excellent imprinting effect and high selectivity. Under optimum magnetic molecular imprinted solid phase extraction (MMISPE) conditions, a wide linear range (0.01–50.0 μg mL−1), with low limits of detection and quantification (0.005–0.01 μg mL−1 and 0.019–0.033 μg mL−1, respectively), was achieved for eight Iridoid glycosides (IGs). Typical chromatograms obtained using MMISPE showed that major interferences around the IGs were eliminated efficiently and matrix interference was minimized. The results suggest that our newly developed method, combining MMISPE with HPLC, could be used for the selective enrichment and determination of IGs.
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preparation of hydrophilic molecularly imprinted polymers via bulk polymerization combined with hydrolysis of ester groups for selective recognition of Iridoid glycosides
Analytical and Bioanalytical Chemistry, 2016Co-Authors: Mingming Zhang, Qianshan Gao, Li Cui, Lizong Chen, Xiao WangAbstract:Hydrophilic molecularly imprinted polymers (H-MIP) with molecular recognition ability for Iridoid glycosides (IGs) have been obtained via bulk polymerization combined with hydrolysis of ester groups. H-MIP were characterized by Fourier transform infrared spectroscopy (FT-IR). The hydrophilcity was measured by the contact angle measurement and the water dispersion stability. The obtained H-MIP demonstrated high selectivity and specific binding ability to five IGs in aqueous media. The group extraction efficiency of molecular imprinted solid-phase extraction (MISPE) for five IGs was investigated, including loading sample, breakthrough volume, washing solvent, and elution solvent. Compared with non-imprinted solid-phase extraction (NISPE), the higher average recovery (95.5 %) of five IGs with lower relative standard deviations values (below 6.1 %) using MISPE combined with high-performance liquid chromatography (HPLC) were achieved at three spiked levels in three blank samples. Under the optimum MISPE conditions, the wide linear range with the correlation coefficient of R 2 ≥ 0.9950 for five IGs with low limits of detection (LOD) and quantification (LOQ) (0.01–0.08 and 0.03–0.27 μg mL−1, respectively) were obtained. Chromatograms obtained using MISPE columns demonstrated that the matrix interference has been minimized and great interferences around IGs were also eliminated efficiently. These results indicated that the developed MISPE-HPLC method was selective, accurate, and applicable for the determination of IGs in water media.
Marjaliisa Riekkola - One of the best experts on this subject based on the ideXlab platform.
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analysis of eleven Iridoid glycosides by micellar electrokinetic capillary chromatography mecc and screening of plant samples by partial filling mecc electrospray ionisation mass spectrometry
Journal of Chromatography A, 2002Co-Authors: Johanna Suomi, Susanne K Wiedmer, Matti Jussila, Marjaliisa RiekkolaAbstract:Of ammonium, lithium and sodium salts of dodecyl sulfate studied as surfactants in the separation of Iridoid glycosides by micellar electrokinetic capillary chromatography (MECC), the last one gave the best results. Eleven neutral Iridoid glycosides were separated by MECC with sodium dodecyl sulfate as surfactant, and the water-micelle partition coefficients of the compounds were calculated. The separation system was coupled via a coaxial sheath flow electrospray interface to a mass spectrometer, and the partial filling technique was used in the on-line analysis. Seven plant species belonging to five genera (Plantago, Veronica, Melampyrum, Succisa and Valeriana) were screened for the Iridoid glycosides by the new method that was developed. The findings confirmed those of an earlier study on five of the Iridoid glycosides. Some new Iridoid glycosides were found in Plantago lanceolata, Veronica spicata and V. chamaedrys.
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extraction of Iridoid glycosides and their determination by micellar electrokinetic capillary chromatography
Journal of Chromatography A, 2000Co-Authors: Johanna Suomi, Heli Siren, Kari Hartonen, Marjaliisa RiekkolaAbstract:Several methods for the extraction of two Iridoid glycosides, catalpol and aucubin, from the plant matrix (Veronica longifolia leaves) were compared. Pressurized hot water extraction and hot water extraction were the most efficient isolation techniques for both. Pressurized liquid extraction and maceration with various organic solvents were also tested. Relative to the amounts extracted with hot water, ethanol extracted only 22% of catalpol and 25% of aucubin and pressurized hot water extracted 83% of catalpol and 92% of aucubin. The lowest relative standard deviations, 22% for catalpol and 8% for aucubin, were achieved with hot water extraction (13 repetitions), and the highest relative standard deviations, 76% for catalpol and 73% for aucubin, with pressurized liquid extraction (five repetitions). A fast capillary electrophoretic method was developed for the quantitative determination of catalpol and aucubin.
Lan-lan Zhou - One of the best experts on this subject based on the ideXlab platform.
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Protective effect of Iridoid glycosides from Paederia scandens (LOUR.) MERRILL (Rubiaceae) on uric acid nephropathy rats induced by yeast and potassium oxonate.
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 2013Co-Authors: Shi-xiang Hou, Wen-jing Zhu, Ming-qun Pang, Joseph Jeffry, Lan-lan ZhouAbstract:Iridoid glycosides of Paederia scandens (IGPS) are an active component isolated from Chinese herb P. scandens (LOUR.) MERRILL (Rubiaceae). Uric acid nephropathy (UAN) is caused by excessive uric acid, which results in damage of kidney tissue via urate crystals deposition in the kidneys. This study aimed to investigate the protective effects of IGPS on UAN in rats induced by yeast and potassium oxonate. Treatment groups received different doses of IGPS and allopurinol (AP) daily for 35 days respectively. The results showed that treatment with IGPS significantly prevented the increases of uric acid in serum and the elevation of systolic blood pressure (SBP), attenuated renal tissue injury, improved renal function and reserved the biological activity of NOS-1. IGPS also inhibited the biological activity of TNF-α and TGF-β1, and suppressed the mRNA expressions of TNF-α and TGF-β1 in renal tissue. Taken together, the present and our previous findings suggest that IGPS exerts protective effects against kidney damage in UAN rats through its uric acid-lowering, anti-inflammatory and immunomodulatory properties. Furthermore, decreasing SBP by up regulation of NOS-1 expression and down regulation of TNF-α and TGF-β1 expression are involved in the effect of IGPS on high uric acid-induced nephropathy.
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Anti-inflammatory and immunomodulatory effects of Iridoid glycosides from Paederia scandens (LOUR.) MERRILL (Rubiaceae) on uric acid nephropathy rats
Life sciences, 2012Co-Authors: Wen-jing Zhu, Ming-qun Pang, Liuyi Dong, Xueying Huang, Shuangmiao Wang, Lan-lan ZhouAbstract:Abstract Aims Uric acid nephropathy (UAN) is due to excessive uric acid, which leads to hyperuricemia and kidney damage via the deposition of urate microcrystals in the kidneys. Iridoid glycosides of Paederia scandens (IGPS) is a major active component isolated from the traditional Chinese herb P. scandens (LOUR.) MERRILL (Rubiaceae). This study aimed to evaluate the anti-inflammatory and immunomodulatory effects of IGPS and its mechanism on UAN rats. Main methods The experimental model of UAN rats was induced by using uricopoiesis promoter adenine and uricase inhibitor potassium oxonate (PO). Treatment groups received three different doses of IGPS, allopurinol (AP) and benzbromarone (BEN) daily for 24 days respectively. The histopathology of renal tissues in UAN rats were assessed for conventional morphological evaluation. The nuclear factor-κBp65 (NF- κ Bp65), monocyte chemoattractant protein-1 (MCP-1) and α-smooth muscle actin (α-SMA) protein expression of renal tissues in UAN rats were investigated by immunohistochemistry. MCP-1 and α-SMA mRNA levels were monitored by method of reverse transcription polymerase chain reaction (RT-PCR). Key findings Treatment with IGPS significantly ameliorated UAN induced renal tissue injury, inhibited the biological activity of NF- κ Bp65, MCP-1 and α-SMA, and suppressed the mRNA expressions of MCP-1 and α-SMA. Significance IGPS exerts a protective effect against renal injury in UAN rats, possesses anti-inflammatory and immunomodulatory effects by inactivating NF- κ Bp65 pathway transmembrane signal transduction, down regulating the expression of MCP-1 and α-SMA to modulate pro-inflammatory mediator production in nephropathy tissue to improve renal fibrosis in UAN rats.
