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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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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 Xue BAI Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments extraction process content determination
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Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis
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作者 Jun TANG Jianguang ZENG +1 位作者 Hao LI Chenzhong JIN 《Agricultural Biotechnology》 CAS 2023年第2期91-95,104,共6页
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex... With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%. 展开更多
关键词 Pueraria edulis Total flavonoids Condensation reflux extraction method Ultrasound-assisted extraction
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Extraction and Content Determination of Shikimic Acid in Pinus elliottii Engelm 被引量:13
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作者 谢济运 陈小鹏 +2 位作者 李志荣 陈芳 粟本超 《Agricultural Science & Technology》 CAS 2010年第3期177-181,共5页
[Objective] The aim was to provide scientific basis for development and utilization of Pinus elliottii Engelm resources.[Method] The extraction process of shikimic acid in Pinus elliottii Engelm was studied,and the co... [Objective] The aim was to provide scientific basis for development and utilization of Pinus elliottii Engelm resources.[Method] The extraction process of shikimic acid in Pinus elliottii Engelm was studied,and the content of shikimic acid was determined by HPLC.The HPLC conditions were as follows;Alltima NH2 (5 μm,4.6 mm × 150 mm) column separation;the mobile phase was acetonitrile-2%H3PO4 (90:10);the flowing velocity was 1 ml/min;test wavelength was 213 nm,the width of belt was 16 nm;reference wavelength was 300 nm,the width of belt was 80 nm.[Result] By the single factor and orthogonal tests,the optimum conditions were found as follows:ethanol concentration 60%,extraction temperature 75 ℃,solid-liquid ratio 1:25,extraction time 2.5 h.The extraction rate of shikimic acid was 1.49%.[Conclusion] Shikimic acid in Pinus elliottii Engelm could be used as a new resource to develop and utilize. 展开更多
关键词 Pinus elliottii Engelm Shikimic acid Ethanol extraction Orthogonal test
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Epigallocatechin gallate content change of the fresh tea leaf homogenates extracted by different methods in extraction and preservation 被引量:4
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作者 YANG Lei GAO Yan-hua ZU Yuan-gang LIU Xiao-na WANG Lei ZU Shu-chong 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期329-331,共3页
The fresh leaves of China green tea, Camellia sinensis, were collected from Fuyang, Zhejiang Province, China, in April. The tea polyphenols was extracted by four different methods (homogenized with distilled water at... The fresh leaves of China green tea, Camellia sinensis, were collected from Fuyang, Zhejiang Province, China, in April. The tea polyphenols was extracted by four different methods (homogenized with distilled water at room temperature, homogenized with 0.3% citric acid (w/v) at room temperature, 5- min boiling and homogenized with distilled water at room temperature, homogenized with 85℃ distilled water), and after preserving at room temperature, the change of the Epigallocatechin gallate (EGCG) contents of the extracts was investigated. Results indicated that the EGCG content of homogenate extracted with 85℃ distilled water was the highest before the extract was preserved, followed by that of the extract homogenized with 0.3% citric acid at room temperature. During preservation, EGCG content changed obviously. The EGCG contents of homogenates extracted with distilled water at room temperature and 85℃ distilled water declined quickly and separately reduced to 21.52% and 54.6% of their initial contents after preservation for 12 h. The EGCG contents extracted by 0.3% citric acid (w/v) solvent at room temperature and 5- min boiling/homogenized with distilled water at room temperature declined relatively slowly ,and separately reduced to 76.9% and 85.16% of their initial contents after preservation for 12 h. It was also found that the citric acid can prevent the degradation of EGCG and the extract solution color is light green 展开更多
关键词 Epigallocatechin gallate (EGCG) Homogenate extraction content change
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Component Content Soft-sensor Based on Neural Networks in Rare-earth Countercurrent Extraction Process 被引量:13
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作者 YANG Hui CHAI Tian-You 《自动化学报》 EI CSCD 北大核心 2006年第4期489-495,共7页
Throught fusion of the mechanism modeling and the neural networks modeling,a compo- nent content soft-sensor,which is composed of the equilibrium calculation model for multi-component rare earth extraction and the err... Throught fusion of the mechanism modeling and the neural networks modeling,a compo- nent content soft-sensor,which is composed of the equilibrium calculation model for multi-component rare earth extraction and the error compensation model of fuzzy system,is proposed to solve the prob- lem that the component content in countercurrent rare-earth extraction process is hardly measured on-line.An industry experiment in the extraction Y process by HAB using this hybrid soft-sensor proves its effectiveness. 展开更多
关键词 RARE-EARTH countercurrent extraction soft-sensor equilibrium calculation model neural networks
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Extraction Process and Content Determination of Total Flavonoids in Ginkgo( Ginkgo biloba L. ) Leaves 被引量:2
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Binghua QIN Xiaohua WANG 《Agricultural Biotechnology》 CAS 2019年第1期171-175,共5页
[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavono... [Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test; and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol; and the total flavonoid contents had a good linear relation in the range of 0. 006 5-0. 039 mg/ml( R^2= 0. 999 9),the average content was stabilized at 1. 135%,and the average recovery of the method was 102. 0%. [Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves. The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves. 展开更多
关键词 GINKGO biloba L. TOTAL FLAVONOIDS extraction process content determination
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Extraction Process and Content Determination of Caffeic Acid in Laggera alata from Different Production Areas of Guangxi 被引量:1
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作者 Jiangcun WEI Yong CHEN +5 位作者 Zujie QIN Jiabao MA Shengbin CHEN Zuliang QUE Jinzhou LI Zijun CHEN 《Medicinal Plant》 CAS 2018年第4期73-76,共4页
[Objectives] To establish a method for determining the content of Laggera alata( D. Don) Sch. Bip. Ex Oliv. using caffeic acid the target component,and to compare the content of caffeic acid in the medicinal materials... [Objectives] To establish a method for determining the content of Laggera alata( D. Don) Sch. Bip. Ex Oliv. using caffeic acid the target component,and to compare the content of caffeic acid in the medicinal materials of L. alata in different production areas of Guangxi.[Methods]The content was determined by Inertsil~ODS-3 chromatographic column C_(18)( 4. 60 mm × 250 mm,5 μm,mobile phase: acetonitrile-0. 1% phosphoric acid( 22∶ 78),detection wavelength: 320 nm,flow rate: 1. 0 m L/min,column temperature: 30℃,and injection volume: 10 μL. [Results] The caffeic acid showed a good linear relationship in the range of injection volume of 0. 025 92-0. 259 2 μg( R =0. 999 5). The average recovery rate was 98. 33%( RSD = 1. 85%). L. alata in different production areas of Guangxi contained the caffeic acid,and there was a great difference in the caffeic acid. L. alata in Baise had the highest content of caffeic acid,while that in Guilin had the lowest content of caffeic acid. [Conclusions]This method can accurately determine the content of caffeic acid and is expected provide a scientific basis for the development and utilization of herbal medicine L. alata. 展开更多
关键词 Laggera alata(D.Don) Sch.Bip.Ex Oliv. HPLC Caffeic acid extraction process content Determination
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Component Content Soft-Sensor Based on Hybrid Models in Countercurrent Rare Earth Extraction Process 被引量:3
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作者 杨辉 王欣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期86-91,共6页
In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth co... In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth component content. The hybrid models were composed of the extraction equilibrium calculation model and the Radial Basis Function (RBF) Neural Network (NN) error compensation model; the parameters of compensation model were optimized by the hierarchical genetic algorithms (HGA). In addition, application experiment research of this proposed method was carried out in the rare earth separation production process of a corporation. The result shows that this method is effective and can realize online measurement for the component content of rare earth in the countercurrent extraction. 展开更多
关键词 countercurrent extraction soft-sensor equilibrium calculation model RBF neural networks hierarchical genetic algorithms rare earths
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Protein Extraction Methods for Two-Dimensional Electrophoresis from Baphicacanthus cusia(Nees)Bremek Leaves-A Medicinal Plant with High Contents of Interfering Compounds 被引量:4
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作者 XIANG Xiao-liang NING Shu-ju +3 位作者 JIANG Xia GONG Xiao-gui ZHU Ren-lei WEI Dao-zhi 《Agricultural Sciences in China》 CSCD 2010年第10期1530-1537,共8页
Protein extraction is a critical step for two-dimensional electrophoresis (2-DE). Different plant samples require different and adaptive protein extraction protocols. The leaves of medicinal plant, Baphicacanthus cu... Protein extraction is a critical step for two-dimensional electrophoresis (2-DE). Different plant samples require different and adaptive protein extraction protocols. The leaves of medicinal plant, Baphicacanthus cusia (Nees) Bremek are notoriously recalcitrant to common protein extraction methods due to high levels of interfering compounds (especially the secondary metabolites and pigments). This study was aimed to establish a routine procedure for the proteomic analysis ofB. cusia leaves, and a new protocol for the protein extraction was developed by optimizing trichloroacetic acid (TCA)/ acetone extraction method. The efficiency of this protocol was demonstrated by comparison with 3 published protein extraction methods (chloroform/acetone, Mg/NP-40, Tris-base/acetone). The results showed that the optimized TCA/ acetone precipitation extraction method gave a relatively high protein yield (9.263 mg g^-1 fresh weight), high-resolution separation, clear protein profiles, the highest proteins spots (1 31 t protein spots), and displayed less contamination in 2- DE gels. Therefore, the results suggested that the optimized TCA/acetone method was the most effective among the 4 methods for B. cusia leaves. 展开更多
关键词 Baphicacanthus cusia (Nees) Bremek medicinal plant protein extraction two-dimensional electrophoresis
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Neural Networks Based Component Content Soft-Sensor in Countercurrent Rare-Earth Extraction 被引量:2
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作者 杨辉 谭明皓 柴天佑 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第6期691-696,共6页
The equilibrium model for multicomponent rare earth extraction is developed using neural networks, which combined with the material balance model could give online prediction of component content in countercurrent rar... The equilibrium model for multicomponent rare earth extraction is developed using neural networks, which combined with the material balance model could give online prediction of component content in countercurrent rare earth (extraction) production. Simulation experiments with industrial operation data prove the effectiveness of the hybrid soft-(sensor). 展开更多
关键词 countercurrent extraction first principle model soft-sensor model neural networks rare earths
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Component content distribution profile control in rare earth countercurrent extraction process 被引量:7
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作者 杨辉 徐芳萍 +1 位作者 陆荣秀 丁永权 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期192-198,共7页
Considering that the on-line measurement and automatic control of element component content(ECC) are difficult to perform in rare earth cascade extraction process, the ECC distribution profile is dynamically regulated... Considering that the on-line measurement and automatic control of element component content(ECC) are difficult to perform in rare earth cascade extraction process, the ECC distribution profile is dynamically regulated at all stages to assess the effect of product purity control. Focusing on the theory of countercurrent extraction, the technology parameters and pre-setting flow-rates during the extract process are designed. Under varying process parameters, a novel step by step model is also proposed for each stage to analyze the impact on the distribution profile change. Combining the mass balance model and ECC changing trend at the monitoring stage, the ECC distribution profile can be automatically regulated by dynamically compensating the related extract or scrubbing liquid flow-rate. To this end, the required product purity at the two outlets is achieved. Based on Wincc and Matlab dynamic simulators, a specific Pr/Nd cascade extraction process is used to illustrate and demonstrate the application of the present approach. 展开更多
关键词 Rare earth cascade extraction Balance model Distribution regulation Pr/Nd
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Extraction Technology of Total Flavonoids from Pueraria lobata (Willd.) Ohwi and Content Determination of Pueraria lobata (Willd.) Ohwi at Different Altitudes 被引量:2
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作者 Chunlin LIU Yingchen LI +1 位作者 Bochao LI Yuan LIU 《Medicinal Plant》 2017年第2期12-14,18,共4页
[Objectives]To optimize the extraction technology of total flavonoids from Pueraria lobata( Willd.) Ohwi. [Methods]The ultraviolet-visible spectrophotometry was used to determine the content of total flavonoids in Pue... [Objectives]To optimize the extraction technology of total flavonoids from Pueraria lobata( Willd.) Ohwi. [Methods]The ultraviolet-visible spectrophotometry was used to determine the content of total flavonoids in Pueraria lobata( Willd.) Ohwi. With the puerarin as index,the reflux extraction and single factor test were employed to investigate the effects of temperature,time,ethanol concentration and solid-liquid ratio on the content of total flavonoids in Pueraria lobata( Willd.) Ohwi,respectively. Under the optimal extraction technology,the content of total flavonoids in Pueraria lobata( Willd.) Ohwi at different altitudes was determined.[Results] The optimum extraction process was as follows: 70%ethanol; solid-liquid ratio of 1∶ 30; 1 h reflux extraction. Under these conditions,the extraction rate of flavonoids in Pueraria lobata( Willd.) Ohwi was 11. 48%,the total flavonoids content of different kudzu parts was in the order of roots > stems > leaves,and the total flavonoids content of the sample at about an altitude of 1000 m was significantly higher than at the altitudes of 1400 m and 1700 m.[Conclusions]It was suggested that the Pueraria lobata( Willd.) Ohwi should not be cultivated as medicinal plant in too high mountains,and the stems and leaves of Pueraria lobata( Willd.) Ohwi could be used as raw materials for extracting total flavonoids. 展开更多
关键词 PUERARIA lobata(Willd.) Ohwi TOTAL FLAVONOIDS extraction technology Different ALTITUDES content determination
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Optimization of ionic liquid-based microwave-assisted extraction of polyphenolic content from Peperomia pellucida (L) kunth using response surface methodology 被引量:7
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作者 Islamudin Ahmad Arry Yanuar +1 位作者 Kamarza Mulia Abdul Mun'im 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第7期660-665,共6页
Objective: To optimize the ionic liquid based microwave-assisted extraction (IL-MAE) of polyphenolic content from Peperomia pellucida (L) Kunth. Methods: The IL-MAE factors as experimental design parameters, including... Objective: To optimize the ionic liquid based microwave-assisted extraction (IL-MAE) of polyphenolic content from Peperomia pellucida (L) Kunth. Methods: The IL-MAE factors as experimental design parameters, including microwave power, extraction time, ionic liquid concentration, and liquid–solid ratio had been involved. Response surface methodology and Box–Behnken design were used to obtain predictive model (multivariate quadratic regression equation) and optimization of the extraction process. The response surface was analyzed by using the yields of total polyphenolic content as response value. Results: Based on the obtained results the optimum extraction condition, including microwave power of 30% Watts, extraction time of 18.5 min, the ionic liquid concen-tration of 0.79 mol/L, and the liquid–solid ratio of 10.72 mL/g 1-Buthyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) as a solvent was selected. The regression model was obtained to predicts the yields from Peperomia pellucida:Y = 30.250 – 1.356X1 + 2.655X2 + 2.252X3 – 0.565X4 + 0.990 X1X3 – 8.172 X1X4 – 3.439 X3X4 – 4.178 X12 – 3.210 X32 – 6.786 X42 – 7.290 X12X3 + 5.575 X1X32 – 4.843 X32X4 with R2 = 0.82519. Scale-up confirmation test was obtained the maximum yields of total polyphenolics content with the amount of 31.1725μg GAE/g. Conclusions: The IL-MAE method produced a higher extraction polyphenolic and performed rapidly, easily and efficiently. 展开更多
关键词 Peperomia pellucida (L) Kunth 1-buthyl-3-methylimidazolium TETRAFLUOROBORATE Response surface methodology Box–Behnken design Polyphenolic content
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Optimization of Extraction Process and Content Determination of Total Flavonoids from Sanguisorbae Radix and Carbonized Sanguisorba Root by Orthogonal Experimental Design 被引量:1
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作者 Fenglin WANG Yunzhang XU +1 位作者 Jingxia WANG Yuan LIU 《Medicinal Plant》 2017年第6期5-9,共5页
[Objectives] To optimize the extraction process of total flavonoids from Sanguisorbae Radix and carbonized Sanguisorba root,compare quality of different batches of Sanguisorbae Radix,study the effects of processing on... [Objectives] To optimize the extraction process of total flavonoids from Sanguisorbae Radix and carbonized Sanguisorba root,compare quality of different batches of Sanguisorbae Radix,study the effects of processing on the content of flavonoids,and provide scientific basis for reasonable utilization of Sanguisorbae Radix. [Methods] Test samples were prepared by heating,refluxing,and extraction,the extraction process was optimized by orthogonal experiment design,color was developed by NaNO_2-Al( NO_3)3-NaOH,and total flavonoids were measured by UV method at the wavelength of 510 nm. [Results] The linear relationship of rutin was excellent in the concentration range of 0. 1248 mg/mL-0. 5712 mg/mL,R^2= 0. 9997; the average recovery was 99. 67% and the RSD was 0. 70%. The optimum extraction conditions were as follows: the volume fraction of ethanol was 50%,the extraction temperature was 90℃,the extraction time was 90 min,and the solid-to-liquid ratio was 1∶ 20( g/mL). [Conclusions] After optimization of the extraction process,the extraction rate of total flavonoids in samples of Sanguisorbae Radix was significantly increased; there was certain difference in the content of total flavonoids between different batches of Sanguisorbae Radix and processed products; the total flavonoids significantly declines in carbonized sanguisorba root,and the influence of processing on its curative effect was to be further studied. 展开更多
关键词 Sanguisorbae RADIX Carbonized sanguisorba ROOT TOTAL FLAVONOIDS extraction process content determination
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Extraction Process and Content Determination of Caffeic Acid in Zhuang Medicine Cryptolepis buchananii
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作者 Chenyan LIANG Lu ZHANG +2 位作者 Yunli TANG Liuyan HE Ganneng HUANG 《Medicinal Plant》 CAS 2019年第6期15-19,共5页
[Objectives]To establish a method for determining the content of caffeic acid in Zhuang Medicine Cryptolepis buchananii.[Methods]The content of caffeic acid in C.buchananii leaves was determined by high performance li... [Objectives]To establish a method for determining the content of caffeic acid in Zhuang Medicine Cryptolepis buchananii.[Methods]The content of caffeic acid in C.buchananii leaves was determined by high performance liquid chromatography(HPLC).[Results]The results of HPLC determination showed that the RSD values were less than 3%,and the content of caffeic acid in 10 batches of C.buchananii leaves was in the range of 0.0965%-0.4772%.[Conclusions]This method is accurate and reliable,has good linear relationship and high precision,and can be used for quality evaluation of C.buchananii. 展开更多
关键词 Cryptolepis buchananii Caffeic ACID High performance LIQUID chromatography(HPLC) extraction process content determination
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Relevance-based content extraction of HTML documents
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作者 吴麒 陈兴蜀 +1 位作者 朱锴 王春晖 《Journal of Central South University》 SCIE EI CAS 2012年第7期1921-1926,共6页
Content extraction of HTML pages is the basis of the web page clustering and information retrieval,so it is necessary to eliminate cluttered information and very important to extract content of pages accurately.A nove... Content extraction of HTML pages is the basis of the web page clustering and information retrieval,so it is necessary to eliminate cluttered information and very important to extract content of pages accurately.A novel and accurate solution for extracting content of HTML pages was proposed.First of all,the HTML page is parsed into DOM object and the IDs of all leaf nodes are generated.Secondly,the score of each leaf node is calculated and the score is adjusted according to the relationship with neighbors.Finally,the information blocks are found according to the definition,and a universal classification algorithm is used to identify the content blocks.The experimental results show that the algorithm can extract content effectively and accurately,and the recall rate and precision are 96.5% and 93.8%,respectively. 展开更多
关键词 content extraction DOM NODE RELEVANCE information block
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Technical Study on Extraction of Procyanidins in Lycium ruthenicum Murr. Using Sub-critical Fluid 1,1,1,2-Tetrafluoroethane( R134a)and Content Determination from Different Producing Areas
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作者 Liang TAN Li ZHU Zhihao FENG 《Medicinal Plant》 CAS 2018年第5期36-40,44,共6页
[Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction ... [Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction rate of procyanidins as an indicator,the influence of pressure,temperature,and extraction time on extraction rate of procyanidins fromL. Ruthenicum Murr. was studied by single factor experimental methods and orthogonal array design. [Results]The order of factors affecting extraction rate of procyanidins was extraction temperature > extraction pressure > extraction time. The optimum extraction conditions were as follows: the extraction rate of procyanidins fromL. ruthenicum Murr. was the highest with extraction pressure of 1. 2 MPa,extraction temperature of 50℃ and extraction time of 90 min. The content of procyanidins in L. ruthenicum Murr. from different producing areas was determined by vanillin-HCl method under the optimal conditions. [Conclusions] The method has the advantages of easy operation,good selectivity,low extraction temperature and high extraction efficiency,which is suitable for extraction of procyanidins in L. ruthenicum Murr. 展开更多
关键词 Lycium ruthenicum Murr. PROCYANIDINS Sub-critical FLUID extraction technology R134A Vanillin-HCl method DIFFERENT producing areas content determination
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Optimization of Ultrasonic-enzymatic Extraction of Total Flavonoids from Cardamine tangutorum O.E.Schulz by Response Surface Methodology and Content Determination 被引量:2
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作者 Xiaoxia CAI Bochao LI +3 位作者 Xuexue LI Hongna SU Wenbing LI Yuan LIU 《Medicinal Plant》 CAS 2020年第6期36-41,共6页
[Objectives]This study aimed to optimize the extraction process of total flavonoids in Cardamine tangutorum O.E.Schulz.[Methods]On the basis of single-factor experiments,the ultrasonic-enzymatic extraction process of ... [Objectives]This study aimed to optimize the extraction process of total flavonoids in Cardamine tangutorum O.E.Schulz.[Methods]On the basis of single-factor experiments,the ultrasonic-enzymatic extraction process of total flavonoids in C.tangutorum O.E.Schulz was optimized by Box-Behnken design from aspects of ethanol volume fraction,extraction time,extraction temperature and enzyme addition,with yield of total flavonoids as the evaluation index.[Results]The optimal extraction process of total flavonoids in C.tangutorum O.E.Schulz was as follows:ethanol volume fraction of 70%,ultrasonic extraction time of 43 min,ultrasonic extraction temperature of 37℃and cellulose addition of 0.07 mg.Under the optimal conditions,the yield of total flavonoids from C.tangutorum O.E.Schulz reached 75.90 mg/g.[Conclusions]The optimized extraction process was reasonable and feasible,and it could provide a reference for the extraction of total flavonoids in C.tangutorum O.E.Schulz.This study provided a foundation for the quality control of food/medicinal materials and the development and research of big health products of C.tangutorum O.E.Schulz. 展开更多
关键词 Cardamine tangutorum O.E.Schulz Total flavonoid Response surface methodology Ultrasonic-enzymatic hydrolysis extraction process
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Thin-layer Identification,Extraction Process and Content Determination of Chlorogenic Acid in Laggera alata(D.Don)Sch.Bip.ex Oliv.
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作者 Qiaofeng QIN Xue JIANG +5 位作者 Jiangcun WEI Jiabao MA Jingrong LU Lifu WEI Xiumei MA Xuanyang ZENG 《Medicinal Plant》 CAS 2020年第6期72-76,共5页
[Objectives]This paper aims to establish thin-layer identification and content determination method for Laggera alata(D.Don)Sch.Bip.ex Oliv.with chlorogenic acid as the index component and compare the content of chlor... [Objectives]This paper aims to establish thin-layer identification and content determination method for Laggera alata(D.Don)Sch.Bip.ex Oliv.with chlorogenic acid as the index component and compare the content of chlorogenic acid in L.alata from different places in Guangxi.[Methods]Silica gel GF254 thin-layer plate was used for identification under an ultraviolet lamp(365 nm),with butyl acetate-formic acid-water(V∶V∶V=7∶2.5∶2.5)as a developing agent.The content of chlorogenic acid was determined under the following chromatographic conditions:column,Inertsil ODS-3 C18 column(4.60 mm×250 mm,5μm);mobile phase,methanol-0.1%phosphoric acid(28∶72);detection wavelength,329 nm;flow rate,1.0 mL/min;column temperature,25℃;and injection volume,10μL.[Results]Chlorogenic acid can be detected by thin layer chromatography with clear spot and good specificity.Chlorogenic acid showed a good linear relationship in the injection amount range of 0.099-0.99μg(R^(2)=0.9999).The content of chlorogenic acid in L.alata varied greatly among the 10 different producing areas in Guangxi.L.alata produced in Dee Township,Longlin,Baise,Guangxi showed the highest chlorogenic acid content,and that produced in Shangsi County and Pingle County showed the lowest chlorogenic acid content.[Conclusions]This method can effectively identify L.alata and accurately determine the content of chlorogenic acid,thereby providing a scientific basis for the development and utilization of L.alata resources. 展开更多
关键词 Laggera alata Chlorogenic acid content determination Thin-layer identification extraction process
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