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Simultaneous determination of five plant hormones in cotton leaves using QuEChERS combined with HPLC‒MS/MS
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作者 WANG Wenhao SONG Xianpeng +7 位作者 WANG Dan MA Yajie SHAN Yongpan REN Xiangliang HU Hongyan WU Changcai YANG Jun MA Yan 《Journal of Cotton Research》 CAS 2024年第2期163-176,共14页
Background Plant hormones profoundly influence cotton growth,development,and responses to various stresses.Therefore,there is a pressing need for an efficient assay to quantify these hormones in cotton.In this groundb... Background Plant hormones profoundly influence cotton growth,development,and responses to various stresses.Therefore,there is a pressing need for an efficient assay to quantify these hormones in cotton.In this groundbreaking study,we have established QuEChERS-HPLC‒MS/MS method,for the simultaneous detection of multiple plant hormones in cotton leaves,allowing the analysis and quantification of five key plant hormones.Results Sample extraction and purification employed 0.1%acetic acid in methanol and C18 for optimal recovery of plant hormones.The method applied to cotton demonstrated excellent linearity across a concentration range of 0.05–1 mg・L−1,with linear regression coefficients exceeding 0.99.The limits of quantification(LOQs)were 20μg・kg−1 for GA3 and 5μg・kg−1 for the other four plant hormones.Recovery rates for the five plant hormones matrix spiked at levels of 5,10,100,and 1000μg・kg−1 were in the range of 79.07%to 98.97%,with intraday relative standard deviations(RSDs)ranging from 2.11%to 8.47%.The method was successfully employed to analyze and quantify the five analytes in cotton leaves treated with plant growth regulators.Conclusion The study demonstrates that the method is well-suited for the determination of five plant hormones in cotton.It exhibits excellent selectivity and sensitivity in detecting field samples,thus serving as a robust tool for indepth research into cotton physiology. 展开更多
关键词 COTTON Plant hormones QUECHERS hplc‒MS/MS
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Determination of Salvianolic Acid B in Yiqi Huayu Prescription by HPLC
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作者 Yingjing WANG Licheng SU +1 位作者 Yuliang HU Zhuqiang WANG 《Medicinal Plant》 2024年第1期32-34,共3页
[Objectives]To determine the content of salvianolic acid B in Yiqi Huayu Prescription by HPLC.[Methods]The chromatographic column was ZORBAX Eclipse Plus C 18(4.6 nm×250 nm,5μm);the mobile phase was acetonitrile... [Objectives]To determine the content of salvianolic acid B in Yiqi Huayu Prescription by HPLC.[Methods]The chromatographic column was ZORBAX Eclipse Plus C 18(4.6 nm×250 nm,5μm);the mobile phase was acetonitrile-0.1%phosphoric acid(21:79),the detection wavelength was 286 nm,the column temperature was 30℃,and the flow rate was 1.0 mL/min.A method for determination of salvianolic acid B in Yiqi Huayu Prescription was established.[Results]The linear relationship of salvianolic acid B was good in the range of 0.0214-0.4064 mg/mL.The regression equation was Y=5995.98984 X-0.07332,r=0.9999.The average recovery rate was 98.88%(RSD=1.6%).[Conclusions]The method is reliable,accurate and specific,and can be used for the determination of salvianolic acid B in Yiqi Huayu Prescription. 展开更多
关键词 Yiqi Huayu Prescription Salvianolic acid B High performance liquid chromatography Content determination
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Determination of Chlorogenic Acid,Geniposide,Total Flavonoids and Total Triterpenes in Wulan-13
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作者 Xiaohua WU Burenbatu 《Medicinal Plant》 2024年第2期6-9,共4页
[Objectives]This study was conducted to establish a method for the determination of chlorogenic acid,geniposide,total flavonoids and total triterpenes in Wulan-13.[Methods]The contents of chlorogenic acid and geniposi... [Objectives]This study was conducted to establish a method for the determination of chlorogenic acid,geniposide,total flavonoids and total triterpenes in Wulan-13.[Methods]The contents of chlorogenic acid and geniposide were determined by HPLC,and the contents of total flavonoids and total triterpenes were determined by an ultraviolet spectrophotometer.[Results]There was a good linear relation between the mass of chlorogenic acid reference substance and the peak area in the range of 0.05-0.45μg,and the regression equation was Y=2524.1X+3.1943,(r=0.9998).A good linear relationship was found between the mass of gardenoside reference substance and the peak area in the range of 0.776-6.984μg,and the regression equation was Y=1670.5X+64.804,(r=0.9998).There was also a good linear relation between the mass of rutin reference substance and its absorbance in the range of 0.00808-0.04848 mg,and the regression equation was Y=12.916X+0.014,(r=0.999).The mass of oleanolic acid reference substance had a good linear relation with its absorbance in the range of 0.00418-0.0209 mg,and the regression equation was Y=51.89X-0.0839,(r=0.9991).[Conclusions]The content determination method is simple,reliable and reproducible,and suitable for controlling the contents of chlorogenic acid,geniposide,total flavonoids and total triterpenes in Wulan-13. 展开更多
关键词 Wulan-13 hplc Ultraviolet spectrophotometer Content determination
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Sex Determination in Homo sapiens as a Multi-Step Process: Potential for Development of Variants and Sex Differences in Disease Risk
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作者 David A. Hart 《Journal of Biomedical Science and Engineering》 2024年第1期13-34,共22页
Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific ... Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific approach has been a successful strategy for survival of a large variety of species including humans, the fidelity of sex determination leading to 100% cis-binary outcomes is not achieved in many species, with evidence for homosexual or bisexual behaviour evident in more than 1500 species. Thus, such outcomes indicates that sex determination is a multi-step process and not a single event, and as such, could lead to the appearance of variants during the process which developed much earlier than humans. Variants could arise either due to intrinsic variation in the steps of determination, or also be influenced by environmental factors of a biological or psychological nature. In contrast to homosexual variants which do not require interventions such as hormone therapy or surgery, expression of gender dysphoria, is more based in psychology, but also has biological underpinnings and can be influenced by such hormonal interventions and surgery. While the numbers of those with gender dysphoria is small (~0.6% - 1.0% of population), the attention given to this issue raises the possibility of biological and psychological environmental factors impacting the emergence of some of those expressing gender dysphoria. Furthermore, transitioning from male-to-female or female-to-male can have consequences regarding disease risks latter in life, including the appearance of autoimmune diseases. This review will attempt to review some of the evidence regarding sex determination, discuss why the system has potentially not been improved upon during evolution, how a potential role for sex chromosome function on neurodevelopment may be central to variation in humans, and how commitment to the current strategy is likely integrated into other sex-related events such as puberty, pregnancy, and menopause to ensure species survival. It will also discuss how variants in sex determination could contribute to sex differences in disease risk and how epigenetic modifications could play a role in such risk. . 展开更多
关键词 Sex determination Variant Development Fidelity of Sex determination Biological Sex determination Species Variation
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Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales
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作者 Qin Ma Zizhen Fan +5 位作者 Ping Wang Siya Ma Jian Wen Fengqin Cao Xianwu Lin Rihui Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期938-947,共10页
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi... transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control. 展开更多
关键词 Zeugodacus cucurbitae TRANSFORMER transformer-2 sex determination RNA interference biological control
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Relative orbit determination algorithm of space targets with passive observation
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作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
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The Impact of Sleep Determination on Procrastination before Bedtime:The Role of Anxiety
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作者 Na Liu Junxiu Wang Wanli Zang 《International Journal of Mental Health Promotion》 2024年第5期377-387,共11页
Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of ... Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of the internet and electronic devices have significantly impacted people’s sleep patterns,particularly through bedtime procrastination.Therefore,this study aims to investigate the relationship and underlying mechanisms between sleep determination,anxiety,and bedtime procrastination among the Chinese population.Method:The study utilized data from a national survey—the China Residents’Sleep Condition Survey(November 2021,with 6,037 participants).By constructing mediation and moderation models,it analyzed the relationship and mechanisms between sleep determination and bedtime procrastination,highlighting the dual role of anxiety:as a mediator between sleep determination and bedtime procrastination,and as a moderator of their relationship.Results:There was a negative correlation between sleep determination and bedtime procrastination;anxiety was related to an increase in bedtime procrastination behaviors;In the interplay between sleep determination and pre-bedtime procrastination,the regulatory effect of anxiety is found to be more pronounced than its intermediary role,with anxiety significantly diminishing the inverse relationship between sleep determination and procrastination before bedtime.Conclusion:Bedtime procrastination can lead to sleep issues,thus reducing sleep quality.Enhancing sleep determination or alleviating pre-sleep anxiety can help inhibit bedtime procrastination behaviors.Intervening and reducing bedtime procrastination is one of the effective measures to improve sleep quality. 展开更多
关键词 Sleep determination bedtime procrastination ANXIETY MEDIATION moderation
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Research Progress on Purification Process, Content Determination and Pharmacological Action of Atractylodin
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作者 Xin SUN Jingwen WANG +1 位作者 Yang XI Chenghao JIN 《Asian Agricultural Research》 2024年第3期33-35,40,共4页
Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rh... Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rheumatic arthralgia.Atractylodin is the main active component extracted and isolated from Atractylodis Rhizoma.A large number of studies have found that atractylodin has excellent drug activity in improving gastrointestinal emptying,anti-inflammation,inhibiting malignant tumor and reducing blood lipid.In this paper,the purification process and pharmacological activity of Atractylodin were summarized to provide a theoretical basis for basic research,clinical application and further development and utilization of atractylodin. 展开更多
关键词 ATRACTYLODIN PHARMACOLOGICAL action PURIFICATION PROCESS CONTENT determination
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Determination of Benzoylaconitine Compounds in the Decoctions of Aconiti Lateralis Radix Praeparata(Heishun Pieces),Trichosanthis Fructus and Their Combination
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作者 Luyao XIE Xiaoxia LI +7 位作者 Jing FU Jinhua LIU Yaobin HUANG Xuri WEI Tingting MO Shaomian PAN Lin HUANG Jiabao MA 《Medicinal Plant》 2024年第3期1-3,22,共4页
[Objectives]This study was conducted to determine the contents of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the decoctions of Heishun pieces,Trichosanthis Fructus and their combination.[Methods]Heis... [Objectives]This study was conducted to determine the contents of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the decoctions of Heishun pieces,Trichosanthis Fructus and their combination.[Methods]Heishun pieces,Trichosanthis Fructus and their combination were extracted for different time periods,and then grouped.HPLC was performed using an Agilent ZORBAX SB-C 18 chromatographic column(4.6 mm×250 mm,5μm)and acetonitrile-0.02 mol/L sodium dihydrogen phosphate as the mobile phase at a flow rate of 1 mL/min and a column temperature of 30℃,and the sample volume was 20μL.The detection wavelength was 230 nm.[Results]The total amounts of benzoylmesaconine,benzoylaconitine and benzoylhypacoitine in the single decoction group of Heishun pieces were all significantly different from those in the combined decoction group at corresponding time.[Conclusions]The total content of the benzoylaconitine type increased significantly after the combined decoction of Heishun pieces and Fructus Trichosanthis,which proves the scientificity of"eighteen incompatible medicaments,19 counteraction"in traditional Chinese medicine to some extent. 展开更多
关键词 Aconiti Lateralis RADIX Praeparata Trichosanthis Fructus Benzoylaconitine COMPOUND CONTENT determination
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Frequentist and Bayesian Sample Size Determination for Single-Arm Clinical Trials Based on a Binary Response Variable: A Shiny App to Implement Exact Methods
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作者 Susanna Gentile Valeria Sambucini 《Open Journal of Statistics》 2024年第1期90-105,共16页
Sample size determination typically relies on a power analysis based on a frequentist conditional approach. This latter can be seen as a particular case of the two-priors approach, which allows to build four distinct ... Sample size determination typically relies on a power analysis based on a frequentist conditional approach. This latter can be seen as a particular case of the two-priors approach, which allows to build four distinct power functions to select the optimal sample size. We revise this approach when the focus is on testing a single binomial proportion. We consider exact methods and introduce a conservative criterion to account for the typical non-monotonic behavior of the power functions, when dealing with discrete data. The main purpose of this paper is to present a Shiny App providing a user-friendly, interactive tool to apply these criteria. The app also provides specific tools to elicit the analysis and the design prior distributions, which are the core of the two-priors approach. 展开更多
关键词 Binomial Proportion Frequentist and Bayesian Power Functions Exact Sample Size determination Shiny App Two-Priors Approach
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TLC Identification of Yao Medicine Pileostegia tomentellal and Extraction Technology and Content Determination of Umbelliferone
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作者 Jiangcun WEI Xiumei MA +5 位作者 Meiyan QIU Bing QING Jingrong LU Hong LEI Xiaodong HUANG Wen ZHONG 《Medicinal Plant》 2024年第2期15-17,20,共4页
[Objectives]To establish a TLC and content determination method of Pileostegia tomentellal,with umbelliferone as the indicator component.[Methods]TLC identification was performed by silica gel G thin layer plate with ... [Objectives]To establish a TLC and content determination method of Pileostegia tomentellal,with umbelliferone as the indicator component.[Methods]TLC identification was performed by silica gel G thin layer plate with n-hexane-ethyl acetate(4:3)as the developing agent,and the plate was examined by UV lamp(365 nm).The umbelliferone content was determined by HPLC:Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm);mobile phase acetonitrile-0.2%phosphoric acid gradient elution;detection wavelength 320 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The chromatogram of P.tomentellal showed the same color spot in the same position as that of reference medicinal material,and the spot was clear with good specificity.Umbelliferone showed a good linear relationship when the injection volume was 2.63-131.27μg/mL(R^(2)=0.9997).The average recovery of umbelliferone in the low,middle and high adding groups of P.tomentellal was 99.57%and the RSD was 2.15%.[Conclusions]The method can effectively identify Yao medicine P.tomentellal and accurately determine the content of umbelliferone in medicinal materials,which will provide a scientific basis for the development and utilization of medicinal resources of Yao medicine P.tomentellal. 展开更多
关键词 Pileostegia tomentellal TLC identification Extraction technology UMBELLIFERONE Content determination
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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Limit Test and pH Determination of 5-Hydroxymethylfurfural in Jiulongteng Honey
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作者 Beiqiao YIN Yanyan CHEN +3 位作者 Lili LIU Shenggao YIN Yanxia CEN Shiman CHEN 《Medicinal Plant》 2024年第3期23-25,29,共4页
[Objectives]To explore the effect of storage time on pH and 5-hydroxymethylfurfural content in Jiulongteng honey.[Methods]The pH of Jiulongteng honey was determined by neutralization titration with sodium hydroxide st... [Objectives]To explore the effect of storage time on pH and 5-hydroxymethylfurfural content in Jiulongteng honey.[Methods]The pH of Jiulongteng honey was determined by neutralization titration with sodium hydroxide standard solution.The content of 5-hydroxymethylfurfural in Jiulongteng honey was determined by HPLC.Chromatographic conditions:ZORBAX SB-C 18 column(250 mm×4.6 mm,5μm)from Agilent Co.,Ltd.,acetonitrile-0.1%formic acid solution(5:95)as mobile phase,flow rate of 0.8 mL/min,5-hydroxymethylfurfural detection wavelength of 284 nm,guanosine detection wavelength of 254 nm.[Results]The pH of 12 batches of Jiulongteng honey was 3.70-3.84 in the new honey stage,3.92-4.05 in the old honey stage 1,and 4.25-4.53 in the old honey stage 2;5-hydroxymethylfurfural was not detected in the new honey stage,5-hydroxymethylfurfural was detected in FM-001 in the old honey stage 1,and 5-hydroxymethylfurfural was detected in most samples in the old honey stage 2.[Conclusions]The pH and 5-hydroxymethylfurfural content of 12 batches of Jiulongteng honey met the requirements within 3 years of storage.There was no 5-hydroxymethylfurfural in Jiulongteng honey,but with the extension of storage time,the detection amount of 5-hydroxymethylfurfural increased significantly even if Jiulongteng honey was stored at low temperature.Therefore,5-hydroxymethylfurfural can be used as an important indicator of honey freshness. 展开更多
关键词 Jiulongteng HONEY 5-HYDROXYMETHYLFURFURAL PH hplc
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Simultaneous Determination of Six Components in Cortex Phellodendri by HPLC
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作者 Lian LIAN Guosheng WAN +1 位作者 Weili JIA Huiyuan GAO 《Agricultural Biotechnology》 CAS 2023年第2期87-90,共4页
[Objectives]This study was conducted to establish the method for simultaneous determination of six active components.[Methods]Simultaneous determination of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,pa... [Objectives]This study was conducted to establish the method for simultaneous determination of six active components.[Methods]Simultaneous determination of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine in Cortex Phellodendri was carried out by HPLC with a Diamonsil C18(4.6 mm×250 mm,5μm)column was used.The mobile phase was acetonitrile-water(1‰acetic acid,2 mmol ammonium acetate)solution in gradient elution.The detection wavelength was set at 280 nm,and the column temperature was kept at 25℃and the flow rate was 1 ml/min.[Results]The linear ranges of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine were 20.00-320.00,18.75-130.00,25.00-200.00,5.00-100.00,20.00-200.00,and 0.09-1.80 mg/L,respectively.The average recovery was 98.1%,99.4%,97.5%,97.3%,104.0%,and 98.5%,respectively;and the RSDs were 0.5%,0.6%,0.8%,1.0%,1.4%,and 0.9%,respectively.[Conclusions]The method is convenient,stable,reliable and suitable for quality control of Cortex Phellodendri. 展开更多
关键词 Cortex Phellodendri Chlorogenic acid Phellodendrine MAGNOFLORINE JATRORRHIZINE PALMATINE BERBERINE determination
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Evaluation of Uncertainty for Determination of Stevioside Content in Fermented Milk by HPLC
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作者 Zhiyong LU Hong YUE +6 位作者 Yuelian NING Xiaoyan HUANG Wenhui HU Shuo TANG Yuju REN Lijun LIU Cuizhi LI 《Asian Agricultural Research》 2023年第1期41-46,共6页
[Objectives]The paper was to establish an evaluation method for the uncertainty of stevioside(including stevioside,rebaudioside A,rebaudioside B,rebaudioside C,rebaudioside F,Dulcoside A,rubusoside and steviolbioside)... [Objectives]The paper was to establish an evaluation method for the uncertainty of stevioside(including stevioside,rebaudioside A,rebaudioside B,rebaudioside C,rebaudioside F,Dulcoside A,rubusoside and steviolbioside)content determination in fermented milk based on HPLC.[Methods]The mathematical model of stevioside content and the propagation rate of uncertainty were established,and the sources of uncertainty were analyzed.[Results]The uncertainty mainly came from four main aspects,including standard uncertainty u(C)introduced by solution concentration C,standard uncertainty u(V)introduced by sample volume V,standard uncertainty u(m)introduced by sample mass m weighing and standard uncertainty u(f_(rep))introduced by measurement repeatability of stevioside content after sample dissolution and constant volume.The uncertainty estimation table and fishbone chart of stevioside content X determination were established.The relative synthetic standard uncertainty of stevioside content was obtained,and the standard uncertainty was extended to form the measurement result of stevioside content and its uncertainty report.[Conclusions]The evaluation results can be directly applied to the daily practical detection work. 展开更多
关键词 hplc STEVIOSIDE Uncertainty Relative synthetic standard uncertainty Extended standard uncertainty
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Simultaneous Determination of Four Pesticide Residues in Fruit Juice by HPLC 被引量:4
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作者 叶剑芝 林玲 +3 位作者 查玉兵 郭宏斌 王明月 杨春亮 《Agricultural Science & Technology》 CAS 2016年第10期2399-2402,共4页
[Objective] This study was conducted to develop a system for simultaneous determination of imidacloprid, diflubenzuron, thiabendazole and carbendazim in fruit juice by HPLC. [Method] Using acetonitrile as the extracti... [Objective] This study was conducted to develop a system for simultaneous determination of imidacloprid, diflubenzuron, thiabendazole and carbendazim in fruit juice by HPLC. [Method] Using acetonitrile as the extraction solvent, the pesticides in fruit juice were purified through a NH2 solid phase extraction (SPE) cartridge, then detected by HPLC. [Result] There was a good linear relationship between the peak area and the concentrations of imidacloprid, diflubenzuron, thiabendazole and carbendazim in a range of 0.05-5.0 μg/ml, and the linear correlation coefficient varied in a range of 0.999 0-0.999 8; the limit of detection for imidacloprid, diflubenzuron, thiabendazole and carbendazim was 0.003, 0.005, 0.003 and 0.007 mg/kg, respectively. The recovery rate of imidacloprid, diflubenzuron, thiabendazole and carbendazim standards added at three levels (0.1, 0.5 and 1.0 mg/kg) ranged from 82% to 107%, with RSD less than 4.5%. [Conclusion] The sensitivity, accuracy and precision of this method were able to meet the requirements for pesticide residue analysis. 展开更多
关键词 hplc Fruit juice Pesticide residues determination
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HPLC同时测定甜高粱中10种黄酮类化合物含量及抗氧化活性对比研究 被引量:1
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作者 李婷 王斐 +3 位作者 何振富 陈平 谢建鹏 王琪 《饲料研究》 CAS 北大核心 2024年第2期116-121,共6页
试验旨在建立同时测定甜高粱不同部位中10种黄酮类化合物含量的高效液相色谱(HPLC)检测方法,并对总黄酮提取物抗氧化能力进行评价。试验以甜高粱陇甜粱2号成熟期籽粒、茎秆及全株为研究对象制备总黄酮提取物,利用HPLC同时测定不同部位... 试验旨在建立同时测定甜高粱不同部位中10种黄酮类化合物含量的高效液相色谱(HPLC)检测方法,并对总黄酮提取物抗氧化能力进行评价。试验以甜高粱陇甜粱2号成熟期籽粒、茎秆及全株为研究对象制备总黄酮提取物,利用HPLC同时测定不同部位总黄酮提取物中的儿茶素、氯化芹菜定、花旗松素、芦丁、槲皮素、木犀草素、柚皮素、高北美圣草素、芹菜素及麦黄酮含量。结果显示,10种黄酮类化合物分别在各自线性范围内与色谱峰峰面积线性关系良好,R^(2)为0.9984~0.9999,平均加样回收率为95.0%~105.8%,RSD为1.03%~2.86%。抗氧化性测定结果表明,甜高粱不同部位总黄酮提取物对羟基自由基、超氧阴离子自由基、1,1-二苯基-2-三硝基苯肼(DPPH)自由基和2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS^(+))自由基均具有一定的清除能力,不同浓度下清除率均表现为籽粒>全株>茎秆;籽粒总黄酮提取物浓度为1.00 g/L时,籽粒总黄酮提取物对DPPH自由基的清除率高于VC和2,6-二叔丁基-4-甲基苯酚(BHT)。相关性分析结果表明,不同部位总黄酮提取物含量与不同自由基清除率及总还原能力(FRAP)均呈正相关。研究表明,该试验方法简便,结果准确性较高,可用于甜高粱中黄酮类化合物含量的测定;甜高粱不同部位总黄酮提取物具有抗氧化活性。 展开更多
关键词 甜高粱 黄酮类化合物 hplc 抗氧化活性
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A rapid HPLC method for determination of coniferyl ferulate in Angelica sinensis and Ligusticum chuanxiong 被引量:3
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作者 于玥 张庆文 +1 位作者 王一涛 李绍平 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期197-201,共5页
Aim A reliable and rapid HPLC method was developed for quantitative determination of coniferyl femlate, an ester of ferulic acid, with multiple pharmacological activities in Angelica sinensis and Ligusticum chuanxiong... Aim A reliable and rapid HPLC method was developed for quantitative determination of coniferyl femlate, an ester of ferulic acid, with multiple pharmacological activities in Angelica sinensis and Ligusticum chuanxiong, two commonly used Chinese medicines. Methods The determination was achieved by using a Zorbax ODS C18 analytical column (250 mm×4.6 mm ID, 5 μm) at isocratic elution of 1% aqueous acetic acid and acetonitrile (1:1) with diode-array detection (318 nm). The calibration curve of coniferyl femlate showed good linearity (r^2 = 0.9995) within the test range. Results The developed method showed good precision with intra- and inter-day variations of 0.22% - 1.16% and 0.86% - 2.62% between the levels of 0.380 - 0.038 mg·mL^-1, respectively. The repeatability represented as RSD of coniferyl femlate was less than 2.7% for three levels (0.2 - 1.0 g of Angelica sinensis), and the recovery was 105.3% with RSD of 3.2%. Conclusion The validated method was successfully applied to quantify coniferyl femlate in 12 samples of Danggui and Chuanxiong. 展开更多
关键词 Coniferyl femlate Angelica sinensis Ligusticum chuanxiong hplc
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HPLC Determination of Harpagoside and Cinnamic Acid in Radix Scrophulariae 被引量:5
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作者 谢丽华 刘洪宇 +4 位作者 徐秉玖 王璇 王建华 徐风 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期148-151,共4页
A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active... A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active constituent (harpagoside) for qualified Radix Scrophulariae. The experimental conditions were as follows: Ultrasphere ODS column (250 mm 4.6 mm, 5 mm), mobile phase: acetonitrile-water (containing 1.0% acetic acid) (20:8050:50) (20 min), flow-rate 1 mLmin-1, room temperature, detection wavelength 278 nm. Twenty-eight samples of Xuan-shen (Radix Scrophulariae) from different districts of China were analyzed and the contents of harpagoside and cinnamic acid in Xuan-shen were 0.041~0.244% and 0.012~0.068% respectively. The recoveries (RSD)% were 97.13(0.80)% for harpagoside and 99.38(0.51)% for cinnamic acid. The method is simple and accurate. It can be used for the quality control of Radix Scrophulariae. We propose that the content of harpagoside in qualified Radix Scrophularia should be no less than 0.05%. 展开更多
关键词 Scrophularia ningpoensis HARPAGOSIDE Cinnamic acid hplc
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Simultaneous Determination of Baicalin, Berberine and Rhein by HPLC in Traditional Chinese Patent Medicine Sanhuang Tablets 被引量:5
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作者 李奕 高建平 许旭 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期110-114,共5页
Aim To establish a reversed phase liquid chromatographic method forsimultaneous determination of three main medicinal constituents, baicalin, berberine and rhein, inSanhuang tablets. Methods The separation was perform... Aim To establish a reversed phase liquid chromatographic method forsimultaneous determination of three main medicinal constituents, baicalin, berberine and rhein, inSanhuang tablets. Methods The separation was performed on a Kromasil C_(18) column with TEA-adjusted0.02 mol·L^(-1) H_3PO_4 (pH 6.78)-acetonitrile-methanol (40 : 9 : 7) as mobile phase at aflow-rate of 1.0 mL·min^(-1), with detection at 254 ran. Considering interaction between acidic andalkaline compounds, three standard markers were added respectively and the volume of samplesolution was doubled in recovery experiments. Results Three regression equations revealed excellentlinear relationship between the peak areas and concentrations and the correlation coefficients allsurpassed 0.999 8. The average recovery was 96.1% (RSD = 2.1%) baicalin, 98.5% (RSD = 2.4%) forberberine, and 101.5% (RSD =1.3%) for rhein. Conclusion The method developed can be used to controlthe quality of Sanhuang tablets comprehensively. 展开更多
关键词 sanhuang tablets BAICALIN RHEIN BERBERINE hplc
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