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61.
Jun Chen Fei Zhu Meiling Pan Qing Liu Lin Chen Yi Tao 《Journal of separation science》2022,45(11):1952-1959
Semens of Astragali Complanati own anti-erectile dysfunction effect; however, the components which contribute to the anti-erectile dysfunction effect remain unclear. This work raised a strategy that integrates liquid chromatography coupled mass spectrometry-based quantitative analysis, anti-erectile dysfunction assessment on impotent rats, and their relationship analysis for pinpointing anti-erectile dysfunction components from semens of Astragali Complanati. For simultaneous quantification of seven major components in raw and salt-processed semens of Astragali Complanati, an accurate and reliable liquid chromatography–mass spectrometry method was developed under multiple reaction monitoring mode. Of note, chloramphenicol was employed as the internal standard. The method showed good linearity and repeatability, where the recovery rates of each component ranged from 98.1 to 104.7%, and the precisions of intra- and interday were all within 3.4%. The method has been used for quantification of the seven major components in 10 batches of raw and salt-processed semens of Astragali Complanati. Then, the anti-erectile dysfunction effects of raw and salt-processed semens of Astragali Complanati were evaluated on impotent rats. Gray relationship analysis and partial least squares regression were combined for elucidating the relationship. As a result, complanatuside, astragalin, complanatoside B, and kaempferol were found to be responsible for anti-erectile dysfunction effect of Astragali Complanati. 相似文献
62.
Jia Fu Qianqian Jia Peida Liang Saisai Wang Huaxin Zhou Liyang Zhang Hong Wang Chunlei Gao Yanni Lv Shengli Han Langchong He 《Journal of separation science》2022,45(14):2498-2507
Cell membrane chromatography is an effective method for screening bioactive components acting on specific receptors in complex systems, which maintains the biological activity of the membrane receptors and improves screening efficiency. However, traditional cell membrane chromatography suffers from poor stability, resulting in a limited life span and low reproducibility, greatly limiting the application of this method. To address this problem, cyanuric chloride-decorated silica gel was used for the covalent immobilization of the cell membranes. Cyanuric chloride reacts with amino groups on the cell membranes and membrane receptors to form covalent bonds. In this way, the cell membranes are not easy to fall off. The column life of the cyanuric chloride-decorated epidermal growth factor receptor/cell membrane chromatography column was extended to more than 8 days, whereas the column life of the normal cell membrane chromatography column dropped sharply in the first 3 days. A cyanuric chloride-decorated epidermal growth factor receptor/cell membrane chromatography online HPLC-IT-TOF-MSn system was applied for screening drug leads from Trifolium pratense L. One potential drug lead, formononetin, which acts on the epidermal growth factor receptor, was screened. Our strategy of covalently immobilizing cell membrane receptors also improved the stability of cell membrane chromatography. 相似文献
63.
Quality control plays a key role in the application of Chinese materia medica, especially in the preparation of traditional Chinese medicine. A pseudotargeted analysis method using an ultra-high-performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry that was operated in the sequential window acquisition of all theoretical spectra mode was proposed to explore the chemical markers of traditional Chinese medicine preparation. Full-scan-based untargeted analysis was applied to extract the target ions. After data preprocessing, 302 target ions were extracted and used for the subsequent sequential window acquisition of all theoretical spectra analyses. The established sequential window acquisition of all theoretical spectra-based pseudotargeted approaches exhibited good repeatability and a wide linear range. The established method was successfully applied to discover analytical markers for the Yuanhu Zhitong tablet. After multivariate statistical analysis, 94 potential markers were identified. Ten markers were annotated by matching accurate m/z and product ion information obtained from previous reports. It is clearly indicated that the pseudotargeted analysis could make a great contribution to the quality assessment of traditional Chinese medicine preparation as a newly emerging technique. 相似文献
64.
Yurui Li Zhenning Ma Hongbo Guo Xiuli Xu Feng Zhang 《Journal of separation science》2022,45(13):2344-2355
A novel magnetic covalent organic framework was synthesized via a one-step coating approach with solvothermal reaction employing 2,4,6-tris(4-aminophen-yl)-1,3,5-triazine and 2,4,6-triformylphloroglucinol as two building blocks by covalent bonding. The prepared magnetic covalent organic frameworks were properly characterized by different techniques and employed as adsorbents of magnetic solid-phase extraction. An analytical method was developed for the simultaneous determination of five fungicides in two Chinese herbal medicine samples via magnetic solid-phase extraction coupled to ultra high performance liquid chromatography with tandem mass spectrometry analysis. Under optimized magnetic solid-phase extraction conditions, the method exhibited satisfactory recoveries (74.0−109.6%) with relative standard deviations of 0.4−4.6%, low limits of detection (0.003−0.015 μg/kg), and good linearity (R2 > 0.9960). Compared with the traditional extraction method, the proposed method required a lower amount of adsorbent (3 mg) and extraction time (5 min). The adsorbent also had favorable reusability (not less than eight times). Therefore, the magnetic covalent organic frameworks could be a promising adsorbent for the extraction and quantitation of fungicides in Chinese herbal medicines. 相似文献
65.
Xi-Yang Tang Zi-Qin Dai Jia-Xing Zeng Zi-Ting Li Cai-Lian Fan Zhi-Hong Yao Xin-Sheng Yao Yi Dai 《Journal of separation science》2022,45(13):2177-2189
In the present study, a specific and sensitive approach using ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry was developed and validated for the quantitative analysis of 14 constituents in rat plasma, liver, and heart. The method was fully validated and successfully applied to pharmacokinetic, hepatic disposition, and heart tissue distribution studies of 14 compounds after the oral administration of Qi-Li-Qiang-Xin capsule. Ginsenoside Rb1, alisol A, astragaloside IV, and periplocymarin were found to be highly exposed in rat plasma, while toxic components such as hypaconitine, mesaconitine, and periplocin had low circulation levels in vivo. Moreover, sinapine thiocyanate, neoline, formononetin, calycosin, and alisol A exhibited significant liver first-pass effects. Notably, high levels of alisol A, periplocymarin, benzoylmesaconine, and benzoylhypaconine were observed in the heart. Based on high exposure and appropriate pharmacokinetic features in the systemic plasma and heart, astragaloside IV, ginsenoside Rb1, periplocymarin, benzoylmesaconine, benzoylhypaconine, and alisol A can be considered as the main potentially effective components. Ultimately, the results provide relevant information for discovery of effective substances, as well as further anti-heart failure action mechanism investigations of Qi-Li-Qiang-Xin capsule. 相似文献
66.
Shuo Gu Tingting Mou Jian Chen Jing Wang Ying Zhang Meirong Cui Wenqian Hao Yue Sun Chengqin Zhang Tiantian Zhao Binbin Wei 《Journal of separation science》2022,45(10):1656-1671
Baihe-Dihuang Tang is a commonly prescribed remedy for depression. In this study, component screening with untargeted and targeted metabolomics was used to identify potential biomarkers for depression in chronic unpredictable mildly stressed rats. Using this novel identification method, the screening of organic acids, lily saponins, iridoids, and other ingredients formed the basis for subsequent metabolomics research. Baihe-Dihuang Tang supplementation in chronic unpredictable mild-stress-induced depression models, increased their body weight, sucrose preference, brain-derived neurotrophic factor deposition, and spatial exploring. Untargeted metabolomics revealed that Baihe-Dihuang Tang exerts its antidepressant effects by regulating the levels of lipids, organic acids, and its derivatives, and benzenoids in the brain, plasma, and urine of the depressed rats. Moreover, it also modulates the d -glutamine and d -glutamate metabolism and purine metabolism. Targeted metabolomics demonstrated significant reduction in l -glutamate levels in the brains of depressed rats. This could be a potential biomarker for depression. Baihe-Dihuang Tang alleviated depression by regulating the levels of l -glutamate, xanthine, and adenine in the brains of depressed rats. Together, these findings conclusively established the promising therapeutic effect of Baihe-Dihuang Tang on depression and also unraveled the underlying molecular mechanism of its potential antidepressant function. 相似文献
67.
In this study, α-glucosidase was successfully immobilized on cellulose filter paper and further applied to screening inhibitors from traditional Chinese medicines combined with capillary electrophoresis analysis. For α-glucosidase immobilization, a cellulose filter paper was used as the carrier and grafted with amino groups by coating chitosan, then α-glucosidase was covalently bonded on the amino-modified carrier via epoxy ring-opening reaction using polyethylene glycol diglycidyl ether as the crosslinker. Several parameters influencing the enzyme immobilization were optimized and the optimal values were enzyme concentration of 4 U/mL, polyethylene glycol diglycidyl ether concentration of 1.25%, chitosan concentration of 7.5 mg/mL, immobilization pH 7.0, crosslinking time of 4 h and immobilization time of 2 h. The immobilized α-glucosidase exhibited good batch-to-batch reproducibility (RSD = 2.1%, n = 5), excellent storage stability (73.5% of its initial activity after being stored at 4°C for 15 days), and reusability (75% of its initial activity after 10 repeated cycles). The Michaelis constant of immobilized α-glucosidase and half-maximal inhibitory concentration of acarbose were calculated to be 1.12 mM and 0.38 μM, respectively. Finally, the immobilized α-glucosidase was used for screening inhibitors from 14 kinds of Traditional Chinese Medicine extracts, and Sanguisorbae Radix showed the strongest inhibitory effect on α-glucosidase. 相似文献
68.
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70.
该文基于酶辅助靶标循环信号放大策略构建了用于黄曲霉毒素B1(AFB1)高灵敏检测的化学发光适体传感器。以G-四链体/氯化血红素DNA酶为信号分子设计了免标记的适体探针H1-S1和发夹探针H2。适体探针结合目标AFB1,在核酸外切酶I辅助下,触发靶标循环反应产生发夹H1。发夹H1与H2杂交,释放出完整的G-四链体序列,并进一步与氯化血红素结合形成G-四链体/氯化血红素DNA酶。DNA酶通过催化氧化鲁米诺-H2O2化学发光体系产生化学发光信号,实现AFB1的放大检测。在最优实验条件下,化学发光强度与AFB1质量浓度的对数在0.001~100 ng/mL范围内呈良好的线性关系,相关系数(r2)为0.9955,检出限为0.93 pg/mL,回收率为93.7%~107%。该适体传感器操作简单、灵敏度高、特异性好,在黄曲霉毒素污染检测方面具有良好的应用前景。 相似文献