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1.
目的 激素是调控植物活性次生代谢产物合成途径的核心调控因子,内源激素结构多样、含量极低,检测难度高,缺乏高效、准确的检测方法。本研究利用超高效液相色谱串联质谱(UHPLC-MS/MS)技术构建了对黄花蒿中茉莉酸、细胞分裂素、赤霉素、生长素、脱落酸等多类植物内源性激素高效定量检测方法。方法 使用Agilent Poroshell 120 EC-C18(2.7 μm, 3.0×150 mm)色谱柱,流动相为0.05%甲酸水-乙腈溶液,梯度洗脱,采用多反应监测模式验证方法可行性,并对黄花蒿不同器官中植物激素进行定量分析。结果 本方法中检测的16种植物激素均呈良好线性,加样回收率、精密度和稳定性均符合植物样品的测定要求。利用此方法测定青蒿不同器官的激素含量,结果表明脱落酸、茉莉酸、茉莉酸甲酯均在叶中含量较高,赤霉素和生长素在根部含量高,细胞分裂素在叶和茎中含量高。结论 青蒿不同器官的激素测定结果可进一步印证脱落酸、茉莉酸、茉莉酸甲酯在调控青蒿素合成中起着重要作用的相关报道,同时表明该方法检测性良好。本文构建的植物内源性激素的检测方法为进一步探究植物生长发育、抵御外界胁迫的相关机制及次生代谢产物的合成等方面提供了手段。  相似文献   
2.
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
3.
Primaquine (PQ) is a racemic drug used in treatment of malaria for six decades. Recent studies suggest that the two enantiomers of PQ are differentially metabolized in animals, and this results in different pharmacological and toxicological profiles. The current study characterizes the pharmacokinetic (PK) properties, metabolism and tolerability of the individual enantiomers of PQ in healthy human volunteers with normal glucose-6-phosphate dehydrogenase (G6PD) activity. Two cohorts (at two dose levels), each with 18 subjects, participated in three study arms in a crossover fashion: a single dose of the (−)-R enantiomer (RPQ), a single dose of the (+)-S enantiomer (SPQ), and a single dose of racemic PQ (RSPQ). PQ and its key metabolites carboxyprimaquine (cPQ) and PQ-N-carbamoyl glucuronide (PQ-N-CG) were analyzed. Clear differences were observed in PK and metabolism of the two enantiomers. Relative PQ exposure was higher with SPQ as compared to RPQ. PQ maximum plasma concentration (Cmax) and area under the plasma concentration-time curve were higher for SPQ, while the apparent volume of distribution and total body clearance were higher for RPQ. Metabolism of the two enantiomers showed dramatic differences: plasma PQ-N-CG was derived solely from SPQ, while RPQ was much more efficiently converted to cPQ than was SPQ. Cmax of cPQ and PQ-N-CG were 10 and 2 times higher, respectively, than the parent drugs. The study demonstrates that the PK properties of PQ enantiomers show clear differences, and metabolism is highly enantioselective. Such differences in metabolism suggest potentially distinct toxicity profiles in multi-dose regimens, especially in G6PD-deficient subjects.  相似文献   
4.
UHPLC-MS/MS测定人血浆中美托洛尔的含量   总被引:1,自引:1,他引:0  
目的 建立测定人血浆中美托洛尔含量的UHPLC-MS/MS分析方法。方法 采用Agilent RRHD PLUS C18色谱柱(2.1 mm×50 mm,1.8 μm),0.2%甲酸水溶液-乙腈(68∶32)为流动相。质谱采用电喷雾离子源(ESI),多反应监测(MRM),检测离子为正离子,分别选择m/z 268/116、237/194作为美托洛尔和内标(卡马西平)的检测离子对。结果 血浆中美托洛尔在1.012~759.0 ng·mL-1内线性关系良好(r=0.999 2)。高、中、低浓度美托洛尔的基质效应分别为105.9%,106.1%,106.9%;平均回收率分别为83.0%,99.3%,95.2%。批内精密度RSD≤3.22%,批间精密度RSD≤4.14%。结论 该方法简便、灵敏、快速、准确,适用于血浆中美托洛尔的含量测定。  相似文献   
5.
应用体外大鼠肝微粒体孵育体系,研究喜炎平注射液中主要有效成分17-氢-9-去氢穿心莲内酯(DHA)的体外代谢速率及代谢产物。将17-氢-9-去氢穿心莲内酯与加入NADPH的大鼠肝微粒体共同孵育,采用超高效液相色谱-三重四极杆串联质谱法(UHPLC-MS/MS)测定其剩余浓度,考察17-氢-9-去氢穿心莲内酯的肝微粒体代谢速率,并采用超高效液相色谱串联飞行时间质谱(UPLC-TOF-MSE)对孵育体系中17-氢-9-去氢穿心莲内酯的代谢产物进行鉴定。研究结果显示在加入辅酶的大鼠肝微粒体中,17-氢-9-去氢穿心莲内酯代谢速率较快,其半衰期(t1/2)和肝微粒体中清除率(CL)分别为(19.7±0.5) min和(35.1±0.8) mL·min-1·g-1。高分辨质谱数据结合文献信息共鉴定孵育体系中17-氢-9-去氢穿心莲内酯的9个代谢产物,主要为羟基化产物和脱氢产物。鉴定结果为筛选出活性更好的穿心莲二萜内酯类衍生物提供了一定的依据。  相似文献   
6.
目的 建立参芪扶正注射液UHPLC-MS特征图谱,以更全面控制产品的质量.方法 运用UHPLC-MS技术,采集总离子流图,确定共有特征峰,用精确质量数提取得到提取离子流图,以黄芪甲苷峰为参照峰,计算各特征峰的相对保留时间,建立特征图谱.结果 确定了18个共有特征峰,建立的特征图谱方法精密度、稳定性、重复性等良好.结论 建立的特征图谱能更全面地评价参芪扶正注射液的化学成分,适用于参芪扶正注射液的快速鉴别,在实际工作中容易推广.  相似文献   
7.
Saikosaponins (SSs) are the main active components extracted from Bupleuri Radix (BR) which has been used as an important herbal drug in Asian countries for thousands of years. It has been reported that the intestinal bacteria plays an important role in the in vivo disposal of oral SSs. Although the deglycosylated derivatives (saikogenins, SGs) of SSs metabolized by the intestinal bacteria are speculated to be the main components absorbed into the blood after oral administration of SSs, no studies have been reported on the characteristics of SGs for their intestinal absorption, and those for SSs are also limited. Therefore, a rapid UHPLC-MS/MS method was developed to investigate and compare the apparent permeability of three common SSs (SSa, SSd, SSb2) and their corresponding SGs (SGF, SGG, SGD) through a bidirectional transport experiment on Caco-2 cell monolayer model. The method was validated according to the latest FDA guidelines and applied to quantify the six analytes in transport medium samples extracted via liquid-liquid extraction (LLE). The apparent permeability coefficient (Papp) determined in this study indicated that the permeability of SGs improved to the moderate class compared to the corresponding parent compounds, predicting a higher in vivo absorption. Moreover, the efflux ratio (ER) value demonstrated an active uptake of SSd and the three SGs, while a passive diffusion of SSa and SSb2.  相似文献   
8.
摘 要 目的:建立一种采用固相净化结合超高效液相色谱-串联质谱法(UHPLC-MS)同时测定九香虫及其3种成方制剂中10种真菌毒素的方法。方法:样品经乙腈-水-甲酸(84∶15.9∶0.1)提取,MFC100固相净化柱净化,采用UHPLC-MS在多反应监测(MRM)模式下进行测定,外标法定量。结果:10种真菌毒素的含量在各自质量浓度范围内具有较好的线性关系(r > 0.999),目标化合物在低、中、高3个质量浓度下的平均回收率为62.3% ~ 106.6%(RSD < 10%),定量限(LOQ)为0.17 ~ 88.04 μg·kg-1。结论:该法前处理步骤简便,净化效果良好,灵敏度高,准确性好,适合于九香虫及其成方制剂中10种真菌毒素的测定。  相似文献   
9.
ObjectiveAstragali Radix (AR) is one of the most widely used traditional Chinese medicines (TCMs) for tonic, which can be divided into wild-simulated and cultivated AR according to its cultivation method. However, whether cultivated AR can replace wild-simulated AR has always been a concern.MethodsIn this study, a rapid, highly sensitive and specific analytical method using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS) was developed to quantitatively measure 12 chemical constituents of AR in the different cultivation methods.ResultsAR samples were analyzed with a good linear regression relationship (R2, 0.9983–0.9995), precisions (relative standard deviation (RSD), 1.31%?2.36%), repeatability (RSD, 2.65%?4.92%), stability (RSD, 1.50%?4.05%), and recovery (95.13%?106.52%). Through the determination of AR samples, we found the components of flavonoids in wild-simulated AR were higher than cultivated AR, the saponins in cultivated AR were higher, the ratio of saponins/flavonoids in cultivated AR was higher than wild-simulated AR.ConclusionBased on this research, it could provide guidance for the quality control of AR.  相似文献   
10.
The administration of growth hormone releasing hormone (GHRH) and its synthetic analogs is prohibited by the World Anti-Doping Agency (WADA). Although there is evidence of their use, based on admissions and intelligence, they do not appear to have been found in anti-doping samples by WADA accredited laboratories. This might be due to their small concentration in urine and limited knowledge about their metabolism, especially for unapproved synthetic analogs. This study investigates the in vitro metabolism and detection of four of the larger GHRH synthetic analogs (sermorelin, tesamorelin, CJC-1295, and CJC-1295 with drug affinity complex) in fortified urine. Nineteen major in vitro metabolites were identified, selected for synthesis, purified, and characterized in house. These were used as reference materials to spike into urine together with commercially available parent peptides and a metabolite of sermorelin (sermorelin(3-29)-NH2) to develop a sensitive liquid chromatography-tandem mass spectrometry method for their detection to help prove GHRH administration. Limits of detection of the target peptides were generally 1 ng/ml (WADA required performance limit) or less.  相似文献   
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