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11.
目的系统阐明复方中药制剂天丹通络胶囊中的化学成分组成,同时建立一种可以实现对中药复杂成分进行精准、快速鉴定的高效分析方法。方法采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS),对天丹通络胶囊中的化学成分进行鉴定分析,通过UPLC-Q-Orbitrap MS扫描提供的化合物精确相对分子质量、多级碎片离子信息,同时与对照品的相对保留时间和质谱数据进行比对,并结合相关参考文献及数据库从而实现对化合物的准确定性。结果共鉴定出40种化学成分,其中主要包括酚酸类、醌类、黄酮类、苯酞内酯类、脂肪酸类及其他类。结论本研究可系统、准确、快速地鉴定天丹通络胶囊中的多种化学成分,并为其药效物质基础及质量控制研究提供了科学的理论依据。  相似文献   
12.
目的:为系统研究复方中药制剂活血通脉片中的化学成分组成,建立采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UHPLC-Q-Orbitrap HRMS)快速识别活血通脉片中多种化学成分的定性分析方法。方法:应用UHPLC-Q-Orbitrap MS技术捕捉未知化合物的精确分子质量及多级碎片离子信息,同时与标准品的相对保留时间和质谱数据信息进行比对,并结合相关参考文献以及Mass Bank、Chemical Book等网络数据库信息实现对未知物的准确快速定性。结果:共鉴定出59种化学成分,其中主要包括酚酸类、醌类、黄酮类、苯酞内酯类、皂苷类及其他类化学成分。结论:本研究建立的方法可系统、快速、准确地识别活血通脉片中的多种化学成分,为其药效物质基础研究、质量控制及进一步临床应用等提供了科学的理论依据。  相似文献   
13.
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse).  相似文献   
14.
李宁 《中草药》2019,50(3):573-581
目的为更加全面、系统、快速地表征参桂胶囊有效化学成分谱,采用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UHPLC-Q-OrbitrapHRMS)技术对参桂胶囊中主要化学成分进行快速识别和归属分类。方法采用ACQUITY UPLC?BEH C18色谱柱(100 mm×2.1 mm,1.7μm),以乙腈(A)-0.1%甲酸水(B)为流动相进行梯度洗脱,以实现化合物的前期分离;然后通过Q-Orbitrap MS正、负离子同时监测,一级全扫描及自动触发二级质谱扫描的模式捕捉未知成分的精确相对分子质量及碎片离子信息,同时与对照品的保留时间和质谱数据信息进行匹配,并结合相关文献以及Chemical Book、Mass Bank等数据库最终实现对中药中复杂成分的快速准确识别。结果本研究共鉴定出40种化学成分,其中包括16种皂苷类、6种有机酸类、13种内酯类及5种其他类。结论本法可快速、准确地识别参桂胶囊中主要化学成分,同时为其进一步的药效物质基础、质量控制及临床合理应用等研究奠定了科学的前期基础。  相似文献   
15.

Ethnopharmacological relevance

Plants of the family Amaryllidaceae are used widely in traditional medicine in South Africa. Several of these, including representatives of the genus Cyrtanthus find use in the treatment of mental illness and age-related dementia.

Aim of the study

Based on the distribution of central nervous system-activating alkaloidal constituents within the genus Cyrtanthus, Cyrtanthus contractus was here explored for such compounds which could interact with acetylcholinesterase (AChE), of significance in the progression of neurodegeneration associated with Alzheimer's disease.

Materials and methods

The known phenanthridone alkaloid narciprimine was isolated via column chromatography of the ethanolic extract of bulbs of Cyrtanthus contractus. The structure of the compound was determined by high field 2D NMR and mass spectroscopic techniques. The classical method of Ellman et al. was used in the determination of AChE inhibitory activity.

Results

The isolation of narciprimine from Cyrtanthus contractus is a landmark find since it has previously only been identified in Zephyranthes, Narcissus and Lycoris, genera endemic to the Americas, Europe and Asia, respectively. Narciprimine exhibited micromolar inhibitory activity (IC50 78.9) against the enzyme acetylcholinesterase.

Conclusion

This work represents the first isolation of narciprimine from an African Amaryllidaceae species, which may be of chemotaxonomic significance. The AChE inhibitory activity of narciprimine, taken together with activities of other structurally similar inhibitors within the series affords further insight to the structural details of the lycorine alkaloid acetylcholinesterase inhibitory pharmacophore.  相似文献   
16.
Etazene (or etodesnitazene) is a novel and highly active synthetic opioid belonging to the rapidly evolving and emerging group of “nitazenes.” Etazene metabolites were identified through analysis of a human urine sample. The sample was obtained from a 25-year-old man who attempted suicide by taking a new psychoactive substances (NPS) cocktail purchased online and was analyzed by ultrahigh performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS). Etazene metabolites were predicted with BioTransformer 3.0, and the exact masses were added to the inclusion list. Eight possible metabolites were identified in the urine sample. N- and O-deethylation were identified as the predominant metabolism routes, resulting in M1 (O-deethylated etazene; most abundant metabolite based on the peak area), M2 (N-deethylated etazene), and M3 (N,O-dideethylated etazene) metabolites. Less abundant hydroxylated products of these deethylated metabolites and etazene were also found. Additionally, in the analysis without β-glucuronidase treatment, M1- and M3-glucuronide phase II metabolites were found. As N- and O-deethylated products seem to be the predominant urinary metabolites, the detection of these metabolites in urine can be useful to demonstrate etazene exposure.  相似文献   
17.
李源  高元平  罗昊  李爱暖  吕露阳  徐燕  严亨秀  曾锐 《中草药》2019,50(12):2856-2861
目的建立一种UPLC-Q-Orbitrap HRMS定量分析方法,同时测定秦艽炮制前后8种化学成分(龙胆苦苷、马钱苷酸、獐牙菜苦苷、獐牙菜苷、木犀草素、异牡荆素、芹菜素、山柰酚)含量的变化。方法采用Waters Acquity UPLC BEH C_(18)(100 mm×2.1 mm,1.7μm)色谱柱,以甲醇-0.1%甲酸水溶液为流动相进行梯度洗脱,体积流量0.3 mL/min,柱温35℃。质谱采用负离子检测模式进行检测。结果秦艽经清炒、酒炙后环烯醚萜类含量均明显升高,且清炒后龙胆苦苷和马钱苷酸含量具有统计学差异。黄酮类在清炒和酒炙后含量变化不大。2类成分总的含量变化为环烯醚萜类成分含量清炒酒炙生品;黄酮类成分含量生品酒炙清炒。结论建立的UPLC-Q-Orbitrap HRMS同时测定秦艽炮制前后8种成分的方法准确、稳定,为进一步研究秦艽炮制前后主要成分的变化奠定了基础。  相似文献   
18.
Hypoglycin A (HGA) and methylenecyclpropylglycine (MCPrG) are formed by some maple trees (Acer species) and have been associated with incidences of atypical myopathy among horses in pastures. In this work, a simple and sensitive ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) method without derivatization was developed for the quantification of HGA and MCPrG in maple samples and validated according to EU guidelines. The LOQ presented here for HGA (16.4 µg/kg) is considerably lower than the lowest published LOQ (500 µg/kg). This method confirms that sycamore and box elder maple contain considerable amounts of HGA and MCPrG. In addition, the presence of the dipeptides hypoglycin B and γ-glutamyl-MCPrG in these two maple species is shown using high-resolution MS. This is the first report on the presence of these dipeptides in maple since 1973. The presence of HGB and γ-glutamyl-MCPrG could change the way we understand animal intoxication following the ingestion of maple.  相似文献   
19.
Cancer preventive reagent trans-resveratrol is intracellularly biotransformed to different metabolites. However, it is still unclear whether trans-resveratrol exerts its biological effects directly or through its metabolite(s). This issue was addressed here by identifying the metabolic pattern and the bioactive form of resveratrol in a resveratrol-sensitive human medulloblastoma cell line, UW228-3. The cell lysates and condition media of UW228-3 cells with or without 100 μM resveratrol treatment were analyzed by HPLC and LC/MS which revealed (1) that resveratrol was chemically unstable and the spontaneous generation of cis-resveratrol reduced resveratrol's anti-medulloblastoma efficacy and (2) that resveratrol monosulfate was the major metabolite of the cells. To identify the bioactive form of resveratrol, a mixture-containing approximately half fraction of resveratrol monosulfate was prepared by incubating trans-resveratrol with freshly prepared rat brain lysates. Medulloblastoma cells treated by 100 μM of this mixture showed attenuated cell crisis. The overall levels of the three brain-associated sulfotransferases (SULT1A1, 1C2 and 4A1) were low in medulloblastoma cells in vivo and in vitro in comparison with that in human noncancerous and rat normal cerebella; resveratrol could more or less up-regulate the production of these enzymes in UW228-3 cells but their overall level was still lower than that in normal cerebellum tissue. Our study thus demonstrated for the first time that trans-resveratrol is the bioactive form in medulloblastoma cells in which the expression of brain-associated SULTs was down-regulated, resulting in the increased intracellular bioavailability and anti-medulloblastoma efficacy of trans-resveratrol.  相似文献   
20.
苏娟  贺亚男  杨鑫  谢慧娟  纪奇森  杨明  张定堃  韩丽 《中草药》2023,54(22):7374-7386
目的 研究阴干、晒干、真空冷冻干燥、热风干燥4种干燥方式对马蓝Baphicacanthus cusia叶化学成分的影响,寻找差异成分,并建立HPLC-DAD同时定量分析5种吲哚类生物碱成分的方法,以期为建立规范的马蓝叶干燥方式提供理论依据。方法 利用UHPLC-Q-Orbitrap HRMS对4种干燥处理的马蓝叶进行定性分析,并结合热图聚类分析(heat map clustering analysis,HCA)、主成分分析(principal component analysis,PCA)和正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)筛选差异成分。结果 共鉴定出67个共有化合物。HCA和PCA将阴干和热风干燥归为一类。OPLS-DA筛选出14个差异成分,多为生物碱类,且呈现出不同的变化规律。HPLC-DAD结果表明,不同干燥方式马蓝叶中的5种吲哚类生物碱含量存在明显差异。其中,热风干燥样品的靛蓝含量最高,靛玉红含量最低;阴干样品的靛红、色胺酮、靛玉红含量最高。结论 不同的干燥方式对马蓝叶的品质有明显影响。热风干燥和晒干有利于吲哚苷水解合成靛蓝,但靛红和靛玉红的含量较低。而阴干和真空冷冻干燥样品的靛蓝含量较低,而靛玉红含量较高。阴干和热风干燥能显著提高马蓝叶药效成分的总含量。建议在初加工马蓝叶时使用阴干或热风干燥,为进一步探究马蓝叶的产地加工方式提供了数据支持,同时也为评估马蓝叶的质量提供了技术支持。  相似文献   
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