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Elucidation of the fragmentation pathways of a complex 3,7-O-glycosyl flavonol by CID, HCD, and PQD on an LTQ-Orbitrap Velos Pro hybrid mass spectrometer

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Chinese Journal of Natural Medicines 2015年第11期13卷 867-872页

作者： yang wen-zhi WU Wan-Ying yang Min GUO De-An Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Laboratory for TCM Standardization Technology Shanghai Institute of Materia Medica Chinese Academy of Sciences

The present study was designed to systematically investigate the ESI-MSn behavior of a complex 3, 7-O-glycosyl flavonol, kaempferol 3-O-α-L-[2,3-di-O-β-D-(6-E-p-coumaroyl)glucopyranosyl]-rhamnopyranosyl-7-O-α-L-rhamnopyranoside(KO) isolated from Epimedium wushanense, and to address the elimination priority among different glycosylation sites and different sugars/substituents. The direct-infusion ESI-MSn experiment of KO was performed on a hybrid LTQ-Orbitrap Velos Pro mass spectrometer in both negative and positive ion modes by three different fragmentation mechanisms(CID, HCD, and PQD). The CID, HCD, and PQD analyses of KO exhibited remarkable discrimination in respect of the scan range, richness, and distribution of product ions through the entire spectra. KO experienced different fragmentation pathways between two ionization modes: the negative mode CID of KO eliminated the glycosyl portions(priority: 7-sugar > 3-substituent and terminal substituents > inner sugar) and produced aglycone product ions at m/z 284.03/285.04; however, abundant sodium-adduct B32 together with subsequent i,jX30 cleavages were found characteristic for the positive mode CID-MSn. The fragmentation pathways by CID for KO were proposed by analyzing the high accuracy ESI-MSn data. Complementary structural information of KO regarding the aglycone and glycosyl portions was obtained by analyzing the ESI-MSn data in both ionization modes. In conclusion, the LTQ-Orbitrap method facilitates highly reliable qualitative analysis of bioactive flavonoids with three alternative fragmentation modes.

关键词：药理学药物性质生化化学

The CUSUM statistic of change point under NA sequences

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 512-520页

作者： LING Jin LI Xiao-qin yang wen-zhi JIAO Jian-ling School of Management Hefei University of TechnologyHefei 230009China Center for Applied Mathematics School of Mathematical SciencesAnhui UniversityHefei 230061China

In this paper,we investigate the CUSUM statistic of change point under the neg-atively associated(NA)sequences.By establishing the consistency estimators for mean and covariance functions respectively,the limit distribution of the CUSUM statistic is proved to be a standard Brownian bridge,which extends the results obtained under the case of an indepen-dent normal sample and the moving average processes.Finally,the finite sample properties of the CUSUM statistic are given to show the efficiency of the method by simulation studies and an application on a real data analysis.

关键词： CUSUM statistic limit distribution NA sequences Brownian bridge

Profiling and identification of chemical components of Shenshao Tablet and its absorbed components in rats by comprehensive HPLC/DAD/ESI-MS^n analysis

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Chinese Journal of Natural Medicines 2018年第10期16卷 791-800页

作者： MIAO wen-Juan HU Ying JIA Li ZHANG Chun-Xia yang wen-zhi ZHANG Ping GUO De-An Department of Pharmacy Institute of Hematology and Blood Disease HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 300193China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Shenshao Tablet(SST),prepared from Paeoniae Radix Alba(PRA)and total ginsenoside of Ginseng Stems and Leaves(GSL),is a traditional Chinese medicine(TCM)preparation prescribed to treat coronary heart disease.However,its chemical composition and the components that can migrate into blood potentially exerting the therapeutic effects have rarely been elucidated.We developed an HPLC/DAD/ESI-MS^n approach aiming to comprehensively profile and identify both the chemical components of SST and its absorbed ingredients(and metabolites)in rat plasma and urine.Chromatographic separation was performed on an Agilent Eclipse XDB C_(18) column using acetonitrile/0.1% formic acid as the mobile phase.MS detection was conducted in both negative and positive ESI modes to yield more structure information.Comparison with reference compounds(t_R,MS^n),interpretation of the fragmentation pathways,and searching of in-house database,were utilized for more reliable structure elucidation.A total of 82 components,including 21monoterpene glycosides,four galloyl glucoses,two phenols from PRA,and 55 ginsenosides from GSL,were identified or tentatively characterized from the 70% ethanolic extract of SST.Amongst them,seven and 24 prototype compounds could be detectable in the plasma and urine samples,respectively,after oral administration of an SST extract(4 g×kg^(–1))in rats.No metabolites were observed in the rat samples.The findings of this work first unveiled the chemical complexity of SST and its absorbed components,which would be beneficial to understanding the therapeutic basis and quality control of SST.

关键词： Shenshao Tablet Paeoniae Radix Alba Total ginsenoside of Ginseng Stems and Leaves Chemical component

TCM-based new drug discovery and development in China

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Chinese Journal of Natural Medicines 2014年第4期12卷 241-250页

作者： WU Wan-Ying HOU Jin-Jun LONG Hua-Li yang wen-zhi LIANG Jian GUO De-An Shanghai Research Center for Modernization of Traditional Chinese Medicine and National Engineering Laboratory for TCM Standardization Technology Shanghai Institute of Materia Medica Chinese Academy of Sciences

Over the past 30 years, China has significantly improved the drug development environment by establishing a series of policies for the regulation of new drug approval. The regulatory system for new drug evaluation and registration in China was gradually developed in accordance with international standards. The approval and registration of TCM in China became as strict as those of chemical drugs and biological products. In this review, TCM-based new drug discovery and development are introduced according to the TCM classification of nine categories.

关键词： China China Food and Drug Administration(CFDA) Traditional Chinese Medicine Regulatory classification Drug discovery Drug development

Oplopanax elatus(Nakai) Nakai: chemistry, traditional use and pharmacology

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Chinese Journal of Natural Medicines 2014年第10期12卷 721-729页

作者： Alexander N.Shikov Olga N.Pozharitskaya Valery G.Makarov yang wen-zhi GUO De-An Saint-Petersburg Institute of Pharmacy 188663Kuzmolovo P 245Russia Shanghai Research Center for TCM Modernization Shanghai Institute of Materia MedicaChinese Academy of Sciences

Oplopanax elatus(Nakai) Nakai, a member of the ancient angiosperm plant family Araliaceae, is used for the treatment of different disorders in the medicine systems of China, Russia, and Korea, and was designated in Russia as a classical adaptogen. Despite extensive studies of classical adaptogens, there are comparatively few reports concerning the chemical composition and pharmacological effects of O. elatus in English. The plant is a potential source of saponins, flavonoids, anthraquinones, terpenes, and other active compounds. Experimental studies and clinical applications have indicated that O. elatus possesses a number of pharmacological activities, including adaptogenic, anti-convulsant, anti-diabetic, anti-fungal, anti-inflammatory, anti-oxidant, blood pressure modulating, and reproductive function effects. In this review, the chemistry, safety, and therapeutic potential of O. elatus are summarized and highlighted to encourage the further development of this plant.

关键词：化学安全身心疲惫辩论

Development of specific and quantitative methods for the quality control of the polysaccharides from sea-tangle and sargassum

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Chinese Journal of Natural Medicines 2016年第12期14卷 954-960页

作者： LONG Hua-Li ZHANG Jing-Xian GUO Ji-Ling SUI Guo-Qi HOU Jin-Jun yang wen-zhi HAN Su-Mei WU Wan-Ying GUO De-An National Engineering Laboratory for TCM Standardization Technology Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia Medica Chinese Academy of Sciences

Polysaccharides from numerous traditional Chinese medicines have been proven as the bioactive ingredients and are hence used as the quality control markers. However, the assessment criteria always show a poor specificity, due to the lack of matic comparison among the analogous herbs. In the present study, two similar materials, namely sea-tangle and sargassum, were selected as the model herbs to develop more specific methods for quality control. Two well-established methods, determination of the total polysaccharides content and monosaccharides composition analysis, were both employed. Based upon the quantitative results, the evaluation criteria of the polysaccharides contents of not less than 2.0% and 1.7% were proposed for sea-tangle and sargassum, tively. Nine identical monosaccharide derivatives appeared on the HPLC chromatograms of the hydrolysis and derivatized solutions of the two drugs. Principal component analysis and orthogonal partial least squares discriminant analysis using the peak areas of monosaccharides derivatives as the variables were performed, and the results indicated that mannuronic acid and xylose with the opposite concentrations in the two drugs were the differential components. A discriminative criterion using the peak area ratio of these two monosaccharides derivatives was proposed for the qualitative identification. In conclusion, a more specific and quantitative quality control method was developed for sea-tangle and sargassum.

关键词： Sea-tangle Sargassum Polysaccharides Quality control

基于UPLC-Q TOF MS的狭叶番泻叶伪品耳叶番泻叶的特征成分发现及掺伪鉴别研究

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药物分析杂志 2024年第4期44卷 610-619页

作者：车爽周军杨文志李晓航赵晨郑新元天津市药品检验研究院天津300070 天津中医药大学中医药研究院天津301617

目的:采用高分辨质谱及组学分析技术分析狭叶番泻叶及耳叶番泻叶化学成分差异,并建立狭叶番泻叶中掺伪耳叶番泻叶的快速检查方法。方法:采用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-Q TOF MS),分别采集13批狭叶番泻叶和9批耳叶番... 详细信息

目的:采用高分辨质谱及组学分析技术分析狭叶番泻叶及耳叶番泻叶化学成分差异,并建立狭叶番泻叶中掺伪耳叶番泻叶的快速检查方法。方法:采用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-Q TOF MS),分别采集13批狭叶番泻叶和9批耳叶番泻叶的正谱和负谱MSE数据。采用Agilent ZORBAX SB-C18(100 mm×2.1 mm,1.8μm)色谱柱,柱温30℃,以乙腈(A)-1%乙酸(B)为流动相,流速0.3 mL·min^(-1),进样体积1μL;采集质量范围为m/z 50~1200。运用组学分析软件QI对狭叶番泻叶和耳叶番泻叶负谱数据进行正交偏最小二乘法判别分析,筛选出7个耳叶番泻叶特征性成分,并对其中的1个主要特征性成分进行了分离鉴定。进一步以主要特征性成分为指标性成分建立了快速检查狭叶番泻叶中掺伪耳叶番泻叶的UPLC方法,并应用于27批狭叶番泻叶样品及3批自制阳性样品的测定。结果:狭叶番泻叶和耳叶番泻叶的化学成分差异显著,经鉴定耳叶番泻叶中特有成分为kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside。在狭叶番泻叶中掺伪耳叶番泻叶的UPLC检查方法中,该特有成分的精密度(RSD=1.3%)、重复性(RSD=1.3%)和稳定性(RSD=0.58%)均符合要求。27批狭叶番泻叶样品中23批未检出kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside;4批狭叶番泻叶样品及3批自制阳性样品中检出kaempferol 3-O-(2”-O-apiofuranosyl)rutinoside。结论:本研究应用UPLC-Q TOF MS技术结合OPLS-DA分析方法成功将狭叶番泻叶和耳叶番泻叶进行了区分,分离并鉴定出耳叶番泻叶的主要特征性成分,并建立了快速筛查狭叶番泻叶中掺伪耳叶番泻叶的UPLC方法,为狭叶番泻叶的质量控制及质量标准的完善提供了依据,为中药材掺伪鉴别研究提供了思路和方法。

关键词：狭叶番泻叶耳叶番泻叶山柰酚3-O-(2”-O-阿哌呋喃基)芸香苷超高效液相色谱-四极杆/飞行时间串联质谱正交偏最小二乘法判别分析掺伪鉴别质量评价比较研究

基于UHPLC-Q-TOF-MS的中药吴茱萸化学成分表征与鉴定

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中国中药杂志 2024年第11期49卷 2953-2964页

作者：王宇胡万弟洪莉丽徐晓艳王洪达王小莹杨文志高秀梅天津中医药大学现代中药创制全国重点实验室天津中医药大学方剂学教育部重点实验室天津301617

基于灵敏、高效的超高效液相色谱-四极杆飞行时间质谱(UHPLC-Q-TOF-MS)技术,结合自建信息数据库,系统地表征与鉴定吴茱萸的化学成分。对色谱分离条件(固定相、流动相、柱温、洗脱梯度)和质谱检测条件(喷嘴电压、毛细管电压、fragmentor... 详细信息

基于灵敏、高效的超高效液相色谱-四极杆飞行时间质谱(UHPLC-Q-TOF-MS)技术,结合自建信息数据库,系统地表征与鉴定吴茱萸的化学成分。对色谱分离条件(固定相、流动相、柱温、洗脱梯度)和质谱检测条件(喷嘴电压、毛细管电压、fragmentor、碰撞能量)进行优化,最终采用HSS T3色谱柱(2.1 mm×100 mm,1.8μm),流动相为0.1%甲酸水-乙腈,流速0.4m L·min^(-1),柱温35℃,电喷雾离子源,在Auto MS/MS模式下进行正、负离子模式质谱数据采集。根据对照品比对、碎片离子信息解析、相关文献及自建信息数据库检索等,从吴茱萸水煎液中共鉴定或推导了92个化合物,包括33个生物碱类、23个黄酮类、12个萜类、12个苯丙素类、12个其他类。其中17个化合物通过对照品比对鉴定,11个化合物为吴茱萸中未报道成分。该研究实现了吴茱萸水煎液中多类别化学成分的快速表征与鉴定,为其药效物质与质量控制研究提供了参考。

关键词：吴茱萸 UHPLC-Q-TOF-MS 化学成分结构鉴定

Convergence Rate of Estimator forNonparametric Regression Model under ρ-mixing Errors

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Chinese Quarterly Journal of Mathematics 2017年第4期32卷 407-414页

作者： ttU Qi HUANG Qian yang wen-zhi LI Xiao-qin School of Mathematical Sciences Anhui University Hefei 230601 China

In this paper, we investigate the nonparametric regression model based on ρ-mixing errors, which are stochastically dominated by a nonnegative random variable. Weobtain the convergence rate for the weighted estimator of unknown function g（x） in pth-mean, which yields the convergence rate in probability. Moreover, an example of the nearestneighbor estimator is also illustrated and the convergence rates of estimator are presented.

关键词： convergence rate pth-mean ρ-mixing sequence nonparametric regressionmodel