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991.
Raushanara Akter Shaikh J. Uddin Joe Tiralongo I. Darren Grice 《Natural product research》2016,30(23):2688-2693
A new diterpenoid glycoside, 6E,10E,14Z-(3S)-17-hydroxygeranyllinalool-17-O-β-d-glucopyranosyl-(1?→?2)-[α-l-rhamnopyranosyl-(1?→?6)]-β-d-glucopyranoside (1) together with the known diterpenoid glycoside (2) and two known flavonoid glycosides (3, 4) were isolated from the methanol extract of Blumea lacera leaves. The structures were determined by the interpretation of their spectroscopic data and comparison with the literature. All compounds were isolated for the first time from B. lacera and evaluated for their cytotoxic activity. Only the new compound (1) showed strong cytotoxic activity with the lowest IC50 value (8.3 μM) being displayed against MCF-7 breast cancer cells. In apoptosis and cell cycle analysis, 1 revealed strong apoptotic activity against MCF-7 cells (45.5% AV+/PI?) after 24 h, but showed no arresting of any of the cell cycle phases in MCF-7. 相似文献
992.
Sylwia Zielińska Joanna Kolniak-Ostek Mariusz Dziadas Jan Oszmiański Adam Matkowski 《液相色谱法及相关技术杂志》2016,39(4):209-219
The accurate profiling of Agastache rugosa phenolic compounds is an indispensable step toward better understanding of the medicinal properties of the species. The applied method based on coupling fast centrifugal partition chromatography and UPLC–qTOF–MS is an alternative and rapid method for the separation and preliminary purification of compounds included in crude extract and can facilitate the detection of minor compounds. Samples were prepared by the extraction of leaves and inflorescences with methanol, dichloromethane, and ethyl acetate. Polyphenolic compounds were separated using fast centrifugal partition chromatography (FCPC) and analyzed by UPLC–qTOF–MS. Rosmarinic acid, chlorogenic acid, and tilianin content were determined in aerial parts during the growth season and in plants of different age. The developed analytical method used in our experiments improved the identification of phenolic compounds and led to the detection of compounds that had not been found in A. rugosa previously. 相似文献
993.
Xiaowei Dong Hongping Huang Rong Wang Shiyu Luo Yahui Mi Yuqing Pan Wei Shen Jiamin Cui Xiaolong Hu Xuexiang Cheng Xinhong Shi Hao Wang 《Journal of separation science》2023,46(19):2300172
Chrysanthemum morifolium cv. Fubaiju is rich in phenolic compounds with various benefits such as anti-inflammatory, antioxidant, and cardiovascular protection. In this study, 12 phenolic compounds, including five flavonoid glycosides and seven quinic acid derivatives, were successfully separated from the flowers of Chrysanthemum morifolium cv. Fubaiju by high-speed counter-current chromatography and preparative high-performance liquid chromatography. Ethyl acetate-n-butanol–acetonitrile–water–acetic acid (5:0.5:2.5:5:0.25, v/v/v/v/v) was selected as solvent system to separate six fractions from the flowers of Chrysanthemum morifolium cv. Fubaiju, and 20% aqueous acetonitrile (containing 0.1% formic acid) was chosen to be the elution solvent in preparative high-performance liquid chromatography for purifying the fractions above. Luteolin-7-O-β-D-glucoside ( 1 ), luteolin-7-O-β-D-glucuronide ( 2 ), apigenin-7-O-β-D-glucoside ( 3 ), luteolin-7-O-β-D-rutinoside ( 4 ), diosmetin-7-O-β-D-glucoside ( 5 ), chlorogenic acid ( 6 ), 1,5-dicaffeoylquinic acid ( 7 ), 1,4-dicaffeoylquinic acid ( 8 ), 3,4-dicaffeoylquinic acid ( 9 ), 3,4-dicaffeoyl-epi-quinic acid ( 10 ), 3,5-dicaffeoylquinic acid ( 11 ), and 4,5-dicaffeoylquinic acid ( 12 ) were isolated with purities all above 95%, respectively. In addition, all isolates were evaluated for their protective effects on H2O2-induced oxidative damage in adult retinal pigment epithelial cells. 相似文献
994.
Insights into the metabolite profiles of Rubus chingii Hu at different developmental stages of fruit
Yu-Jiao Hua Fen Xie Kun-jun Mao Yi-Yuan Luo Yong-Juan Ding 《Journal of separation science》2023,46(16):2300264
The fruits of Rubus chingii Hu have high medicinal and nutritional values. However, the metabolite profiles of R. chingii, especially the alterations during different development stages of fruit, have not been comprehensively analyzed, hindering the effective utilization of the unique species. In this study, we comprehensively analyzed the metabolites of R. chingii fruit at four developmental stages using systematic untargeted and targeted liquid chromatography-mass spectrometry metabolomics analysis and identified 682 metabolites. Significant changes were observed in metabolite accumulation and composition in fruits during the different developmental stages. The contents of the index components, kaempferol-3-O-rutinoside and ellagic acid, were the highest in immature fruit. The analysis identified 64 differentially expressed flavonoids and 39 differentially expressed phenolic acids; the accumulation of most of these differentially expressed metabolites decreased with the developmental stages of fruit from immaturity to maturity. These results confirmed that the developmental stages of fruit are a critical factor in determining its secondary metabolite compositions. This study elucidated the metabolic profile of R. chingii fruit at different stages of development to understand the dynamic changes in metabolites. 相似文献
995.
Alkylresorcinols (∑ARs) is the generic term for a highly varied class of lipids found mainly in cereals. These bioactive compounds consist mainly of 5-alkylresorcinols (ARs), which differ in length, unsaturation, and substituents on the alkyl side chain on C-5. In addition, 2-methyl-5-alkylresorcinols (mARs) are scarcely studied minor compounds that are supposed to exist with the same structural diversity. In the first step, ∑ARs were enriched by solid-phase extraction from wheat grain and quinoa seed extracts. The subsequent application of silver ion chromatography (SIC), silica gel, coated with 20% AgNO3, then deactivated with 1% water) enabled an unprecedented full separation of saturated mARs from conventional ARs. Specifically, saturated mARs were eluted with n-hexane/ethyl acetate (92:8, v/v), and conventional ARs with n-hexane/ethyl acetate (80:20, v/v). The unpreceded separation indicated that the SIC method could be useful not only for separations according to the degree of unsaturation, but also in the case of steric hindrance by additional (alkyl) substituents. Continued fractionation enabled the collection of unsaturated ARs in wheat and quinoa extracts. In this way, 35 ∑ARs (including five mARs) were detected by gas chromatography/mass spectrometry analysis in wheat and 45 ∑ARs (including 21 mARs) in quinoa. These included several low abundant and partly unknown ∑ARs such as 1,3-dihydroxy-5-tricosadienylbenzene. 相似文献
996.
Four new 8-O-4' type neolignan glycosides with enantiometric aglycones, (7S,8R)-erythro-guaiacylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (1), (7R,8S)-erythro-guaiacylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (2), (7S,8R)-erythro- syringylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (3) and (7R,8S)-erythro- syringylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (4), were isolated from the leaves of Osmanthus ilicifolius. Their structures were established on the basis of NMR, circular dichroism (CD), MS and chemical data. The NMR assignments for the compounds were carried out using (1)H, (13)C, COSY, HMQC, HMBC and NOESY NMR experiments. 相似文献
997.
First Synthesis of Bioactive Diphyllin Glycosides Isolated from Justicia patentiflor Hemsl 总被引:2,自引:0,他引:2
The syntheses of three naturally occurring diphyllin glycosides have been achieved. 7-O-β-D-Qtfmovopyranosyldiphyllin (patentiflorin A) and 7-O-β-L-fucopyranosyldiphyllin (patentiflorin B) were synthesized by the glycosylation of diphyllin with peracetylglycosyl bromides under phase transfer catalysis (PTC) conditions. 4"-O-Acetyl-7-O-β-L-fucopyranosyldiphyllin (4"-O-acetyl patentiflorin B) was obtained from patentiflorin B on an orthoesterification-orthoester rearrangement approach. Their ^1H NMR, ^13C NMR and HRMS signals are all consistent with those reported for the natural product. 相似文献
998.
999.
Cao J Wei YJ Qi LW Li P Qian ZM Luo HW Chen J Zhao J 《Biomedical chromatography : BMC》2008,22(2):164-172
A high-performance liquid chromatographic (HPLC) method coupled with ultraviolet (UV) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) was established for simultaneous qualitative and quantitative determination of nine phenolic acids and six diterpenoids in Radix et Rhizoma Salviae Miltiorrhizae (RRSM). The optimal chromatographic conditions were achieved on a Zorbax C(18) column by gradient elution with 0.1% (v/v) aqueous formic acid and acetonitrile as mobile phase at the flow rate of 1.0 mL/min. The detection wavelength at 281 nm was chosen to determine the 15 bioactive components, namely danshensu (1), protocatechuic acid (2), protocatechuic aldehyde (3), caffeic acid (4), rosmarinic acid (5), lithospermic acid (6), salvianolic acid B (7), salvianolic acid A (8), salvianolic acid C (9); dihydrotanshinone I (10), cryptotanshinone (11), tanshinone I (12), methylene tanshiqunone (13), tanshinone IIA (14) and miltirone (15). Additionally, LC-ESI-TOF/MS was used to make definite identification of the constituents in samples in comparison with those reference compounds. The validation of the method included tests of linearity, sensitivity, repeatability, stability and recovery. The proposed method was successfully applied to quantify the 15 components in 21 samples; significant variations were demonstrated in the contents of the samples from diverse species and origins. The developed method could be used to effectively and comprehensively evaluate the quality of RRSM for its clinical safety and efficacy. 相似文献
1000.
Wei‐Wei Dong Wei Jiao Mei‐Cai Deng Chun‐Bin Yang Jian‐Min Yue Run‐Hua Lu 《中国化学会会志》2008,55(6):1277-1279
A new steroid glycoside derivative, 4′‐O‐docosanoyl‐3‐O‐β‐D‐glucosyl‐sitosterol, along with six known steroids has been isolated from the ethanol extract of the rhizoma of Acorus calamus L. The structures of the new and known compounds were established on the basis of extensive 1D and 2D NMR spectral data. 相似文献