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Determination of Isoflavone from Soybean Lines Cultivated in Jilin Province and Correlation Analysis between Isoflavone Content and Soybean Quality 被引量:29
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作者 宋向东 张之鑫 +1 位作者 王巍巍 富健 《Agricultural Science & Technology》 CAS 2010年第1期48-50,共3页
[Objective]The aim of this study was to set up a high performance liquid chromatography for rapid determination of isoflavones from soybean and analyze the correlation between isofalvone content and protein or fat con... [Objective]The aim of this study was to set up a high performance liquid chromatography for rapid determination of isoflavones from soybean and analyze the correlation between isofalvone content and protein or fat content. [Method]The isoflavones were firstly extracted by 80% methanol and then hydrolyzed at 100 ℃. The chromatographic separation adopted a reversed-phase C18 analytical column with binary high-pressure gradient elution,while its analysis time was 25 min and column temperature was 40 ℃. The diode array detector was used for monitoring with wavelength of 260 nm. The correlation between isofalvone content and protein or fat content was analyzed by data processing system Origin 6.0. [Result]The high performance liquid chromatograph for determination of isoflavones from soybean was verified to be accurate and reliable by methodology. The isoflavones of 85 soybean lines cultivated in Jilin Province were determined,and the results primarily showed the characters and ranges of isoflavones from soybean lines cultivated in Jilin Province,while the isoflavone content of soybeans ranged from 2.29 to 4.89 mg/g,and the average content was 3.36 mg/g. The isoflavone content of 5 soybean lines exceeded 4 mg/g,while there was a remarkably negative correlation between isoflavone content and protein content,and there was no significant positive correlation between isoflavone content and fat content. [Conclusion]The isoflavone content of soybean lines cultivated in Jilin Province is higher,so it is feasible for breeding the soybean lines with high isoflavone content and fat contetnt. 展开更多
关键词 Cultivated soybean Isoflavone content determination Protein content Fat content
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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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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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Determination of total flavonoids content in buckwheat and inhibition of α-amylase activity
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作者 Huijing Chao Rong Yang +2 位作者 Ming Yang Beijie Xu Xu Zhao 《Journal of Polyphenols》 2024年第3期98-105,共8页
Diabetes is one of the most difficult chronic diseases to cure in the world,which seriously affects people’s health and quality of life.Flavonoids in buckwheat can regulate blood glucose levels by inhibitingα-amylas... Diabetes is one of the most difficult chronic diseases to cure in the world,which seriously affects people’s health and quality of life.Flavonoids in buckwheat can regulate blood glucose levels by inhibitingα-amylase activity.Therefore,sweet buckwheat produced in Inner Mongolia was used as the research object,and buckwheat fl avonoids were extracted by ultrasonic-assisted extraction method.Total fl avonoids content was determined by ultraviolet-visible spectrophotometry.With acarbose as the positive control,the inhibition test ofα-amylase was carried out by DNS colorimetry to study the inhibition behavior of fl avonoids onα-amylase activity.The results showed that the extraction process of flavonoids was stable and reliable,and the established method for the determination of flavonoids was simple,accurate and reproducible.The total flavonoids content of buckwheat samples was 2.706 mg/g,buckwheat total fl avonoids extraction solution had an inhibitory eff ect onα-amylase,and its median inhibition concentration(IC_(50))was 38.53 mg/mL.The results of this experiment provide a technical reference for the development and utilization of fl avonoids in Inner Mongolia sweet buckwheat,and provide a theoretical reference for the development and application of flavonoid-rich hypoglycemic food. 展开更多
关键词 BUCKWHEAT total flavonoids content Α-AMYLASE activity inhibition
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Rapid Determination of Silicon Content in Rice 被引量:4
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作者 DAI Wei-min ZHANG Ke-qin +4 位作者 DUAN Bin-wu SUN Cheng-xiao ZHENG Kang-le CAI Run ZHUANG Jie-yun 《Rice science》 SCIE 2005年第2期145-147,共3页
A method for rapid determination of silicon content in rice was introduced. The reliability of this method was verified by using a recombinant inbred line (RIL) population of rice cross Zhenshan 97B / Milyang 46. Tw... A method for rapid determination of silicon content in rice was introduced. The reliability of this method was verified by using a recombinant inbred line (RIL) population of rice cross Zhenshan 97B / Milyang 46. Two hundred and forty-nine RILs were transplanted in two replications. Simple correlation coefficients on the silicon content in the hull, flag leaf and stern in rice between duplicate samples of 498 rice materials were 0.97954, 0.97026 and 0.98848, respectively. Ten representative samples were selected for measurement using the high-temperature alkaline fusion method. Simple correlation coefficient between the silicon contents determined by the high-temperature alkaline fusion method and by the present method is 0.9993. 展开更多
关键词 RICE silicon content determination method
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Determination of β-sitosterol Content in Ethnodrug Guoshangye 被引量:1
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作者 马四补 张应蓉 +1 位作者 屈相玲 靳凤云 《Agricultural Science & Technology》 CAS 2015年第11期2546-2548,共3页
[Objective] The contents of β-sitosteml in Guoshangye from different habi- tats were determined. [Metlmd] UPLC-ELSD was adopted to determine the contents of β-sitosteml in Guoshangye from different habitats, in whic... [Objective] The contents of β-sitosteml in Guoshangye from different habi- tats were determined. [Metlmd] UPLC-ELSD was adopted to determine the contents of β-sitosteml in Guoshangye from different habitats, in which BEH C18 column (2.1 mmx50 ram, 1,7 urn) was used with a mobile phase of methanol-water at a flow rate was of 0.3 ml/min, and the column temperature was of 30 ℃; and an evaporative light-scattering detector was used, the temperature in drift tube was of 90 ℃ and the pressure of N2 was of 20 psi. [Concludoa] This research provided theoretical foundation for the determination of β-sitosterol in Ethnodrug Guoshangye. 展开更多
关键词 Β-SITOSTEROL Ethnodrug Guoshanye determination
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Comparison between Double Crystals X-ray Diffraction and Micro-Raman Measurement on Composition Determination of High Ge Content Si_(1-x)Ge_(x) Layer Epitaxied on Si Substrate 被引量:1
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作者 Lei ZHAO Yuhua ZUO Buwen CHENG Jinzhong YU Qiming WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期651-654,共4页
It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction (DCXRD) and mi... It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction (DCXRD) and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD. 展开更多
关键词 Si1-xGex Ge content Composition determination Double crystals X-ray diffraction (DCXRD) Micro-Raman measurement
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Determination of Phytoene Content in Tomato Ketchup by HPLC
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作者 吴增宝 薛林 +3 位作者 田珊珊 朱启军 田洁 彭代萍 《Agricultural Science & Technology》 CAS 2016年第11期2627-2628,2635,共3页
[Objective] The aim was to establish an HPLC method for determination of phytoene content in tomato ketchup. [Method] The chromatographic conditions were as follows: column, Agilent AT C18 (250 mm×4.6 mm, 5 μm... [Objective] The aim was to establish an HPLC method for determination of phytoene content in tomato ketchup. [Method] The chromatographic conditions were as follows: column, Agilent AT C18 (250 mm×4.6 mm, 5 μm); mobile phase, methanol-THF (75:25); detection wavelength, 287 nm; flow rate, 1.0 ml/min; column temperature, 30 ℃; sample size, 50 μl. [Result] There was a good linear relation- ship in the phytoene content range of 0.186-1.116μg. The average recovery rate was 103.8% with RSD of 1.47%. The phytoene content in the tomato ketchup sample was determined as 10.7 rag/100 g simple, accurate, rapid and reliable, and phytoene content in tomato ketchup. [Conclusion] The established method is it can be used for the determination of 展开更多
关键词 TOMATO PHYTOENE HPLC content determination
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Chemical Analysis Method for Magnesia and Magnesia-Alumina Refractories——Gravimetric-Molybdenum Blue Photometric Method for Determination of Silicon Dioxide Content 被引量:1
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作者 Wang Jing 《China's Refractories》 CAS 2007年第1期39-41,共3页
This standard specifies the gravimetric-molybdenum blue photometric method for determination of silicon dioxide content.
关键词 Chemical Analysis Method for Magnesia and Magnesia-Alumina Refractories Gravimetric-Molybdenum Blue Photometric Method for determination of Silicon Dioxide content
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Determination of Chlorine Content in Zirconia Containing Special Refractories
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作者 XU Xiaoying CAO Haijie +1 位作者 DUAN Xueke LEI Xiaoyu 《China's Refractories》 CAS 2022年第3期38-41,共4页
In this study,zirconia containing refractory samples were decomposed by dilute nitric acid.The chloride ion content in the leaching solution was determined by thiocyanate spectrophotometry.The influences of the leachi... In this study,zirconia containing refractory samples were decomposed by dilute nitric acid.The chloride ion content in the leaching solution was determined by thiocyanate spectrophotometry.The influences of the leaching method of the sample pretreatment and the coloration condition of the solution to be tested on the test results were studied.The precision test was carried out and the results were compared with those determined by ion chromatography.The results showed that the zirconia containing refractories were boiled with dilute nitric acid to obtain the test solution.The influence of zirconium hydrolysis on determination was removed by centrifugation.The chlorine contents in zirconia containing refractories determined by spectrophotometry have low relative standard deviation(RSD),showing slight testing difference with those determined by ion chromatograghy. 展开更多
关键词 ZIRCONIA refractory materials chlorine content determination
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DETERMINATION OF NUCLEAR DNA CONTENT IN LEIOMYOMA AND LEIOMYOSARCOMA OF GASTROINTESTINAL TRACT
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作者 柳凤轩 贺光友 +1 位作者 李才安 付晓岚 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期69-72,共4页
Nuclear DNA content was measured by micro-spec trophotometry in 15 biopsy specimens from patients with gastrointestinal (GI) tract smooth muscle tumors (3 leiomyomas and 12 leiomyosarco-mas subdivided into 3 groups wi... Nuclear DNA content was measured by micro-spec trophotometry in 15 biopsy specimens from patients with gastrointestinal (GI) tract smooth muscle tumors (3 leiomyomas and 12 leiomyosarco-mas subdivided into 3 groups with 4 cases to each). The mean DNA value increased steadily as follows: leiomyoma (14.39±0.62 Au); leiomyosarcoma Grade Ⅰ (19.78±2.39 Au); leiomyosarcoma Grade Ⅱ (26.39± 1.60 Au); leiomyosarcoma Grade Ⅲ (30.66±2.39 Au). The difference of DNA value in the 4 groups had statistical significance (p<0.05-0.01). These results suggest that microspectrophotometric measurement of nuclear DNA content may serve as an objective quantitative method for the diagnosis of GI tract smooth muscle tumors and classification of leiomyosarcoma. 展开更多
关键词 DNA determination OF NUCLEAR DNA content IN LEIOMYOMA AND LEIOMYOSARCOMA OF GASTROINTESTINAL TRACT
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Determination of the Content of Five Active Components in Toad Skin
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作者 Xue JIANG Wenli LI +1 位作者 Yong CHEN Jiabao MA 《Medicinal Plant》 CAS 2023年第4期38-40,共3页
[Objectives] To establish a method for the determination of active components in toad skin. [Methods] HPLC method was used to determine the content of five active components (bufotalin, cinobufotalin, bufalin, cinobuf... [Objectives] To establish a method for the determination of active components in toad skin. [Methods] HPLC method was used to determine the content of five active components (bufotalin, cinobufotalin, bufalin, cinobufagin and resibufogenin) in toad skin. [Results] Chromatographic conditions are as follows: Agilent ZORBAX SB-C 18 chromatographic column was used;acetonitrile (A)-0.3% glacial acetic acid (B) gradient elution (0-15 min, 28%A-54%A;15-35 min, 54%A-54%A) was conducted;the flow rate was 0.6 mL/min;the detection wavelength was 296 nm;the column temperature was 30 ℃;the sample size was 10 μL. Under the above conditions, the determination method of the five components can be established at one time. [Conclusions] The method was stable and reliable, and can provide experimental basis for the development and utilization of active ingredients in toad skin. 展开更多
关键词 Toad skin High performance liquid chromatography determination of content
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Chemical Analysis Method for Carbon Bearing Refractory Products——Determination of Magnesium Oxide Content by CyDTA Volumetric Method
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作者 Zhang Xiaohui 《China's Refractories》 CAS 2007年第1期37-38,共2页
This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
关键词 determination of Magnesium Oxide content by CyDTA Volumetric Method TEST Chemical Analysis Method for Carbon Bearing Refractory Products
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Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials——Flame atomic absorption spectrometric method for determination of calcium oxide content
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作者 ZHANG Xiaohui 《China's Refractories》 CAS 2006年第4期41-43,共3页
1 Scope This standard specifics the determination of calcium oxide coutent by flame atomic absorption spectrometric method.
关键词 Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials Flame atomic absorption spectrometric method for determination of calcium oxide content
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Determination of Coenzyme Q_(10) Content by RP-HPLC and Daily Change of Transmittance of Co-Q_(10)
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作者 高代升 白琦 +3 位作者 龚文 邓军 方泽银 祝春光 《Agricultural Science & Technology》 CAS 2010年第11期62-64,110,共4页
[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography(RP-HPLC)method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co... [Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography(RP-HPLC)method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co-Q10,and the ultraviolet spectro-photometry was used to analyze the daily change of transmittance of Co-Q10.[Result] By using RP-HPLC,Co-Q10 had a good linear relationship between 40-300 μg/ml(r=0.999 9).The limit of detection was 0.4 ng and the average recovery was 97.44%(n=3).The system suitability of HP-HPLC was good,and the average recovery and precision results could meet the needs of assay.[Conclusion] This method was convenient,accurate and reproducible and could be used in quality control of Co-Q10.However,when it operates,light should be evaded. 展开更多
关键词 RP-HPLC Co-Q10 content determination TRANSMITTANCE
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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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Determination of Amylose Content and Its Relationship with RVA Profile Within Genetically Similar Cultivars of Rice(Oryza sativa L.ssp.japonica) 被引量:10
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作者 WANG Xin-qi YIN Lin-qing +2 位作者 SHEN Ge-zhi XU Li LIU Qiao-quan 《Agricultural Sciences in China》 CAS CSCD 2010年第8期1101-1107,共7页
Anther culture pure lines with antisense Wx gene were generated by Agrobacterium tumefaciens-mediated co-transformation followed by anther culture in transgenic rice (Oryza sativa L. ssp. japonica). The antisense Wx... Anther culture pure lines with antisense Wx gene were generated by Agrobacterium tumefaciens-mediated co-transformation followed by anther culture in transgenic rice (Oryza sativa L. ssp. japonica). The antisense Wx transgenic pure lines were used to analyze the differences and the relationship between RVA eigenvalues among the lines with different amylose contents. 77 pure lines of anther culture having antisense Wx gene were studied for the amylose content of its offspring cultivar, Wuyunjing 7. It was found that levels ofamylose content were similar to the control in 19 lines (16.0%); 1-5% lower than control in 50 lines, of which, within 11.0-13.9% in 40 lines; and 3.1-4.0% in 8 lines. The effect of the amylose content on RVA eigenvalue was analyzed through the RVA profile graphic comparison and test of significance for RVA eigenvalues. The analysis of RVA profiles with different amylose contents indicated that there were two kinds of RVA profiles within genetically similar cultivars. The lines with 3.1-4.0% of amylose content were distinctly different from other lines and conventional glutinous rice. The comparison of the similarity curve of RVA profile of the lines with different amylose contents showed that the lines with lower amylose content had a distinguished RVA profile with the curve increasing gradually, but not exceeding the first apex. The test of significance for eigenvalues of the RVA profile in the lines with different amylose contents indicated that there were five eigenvalues remarkably different among the lines with 3.1-4.0% of amylose content compared with other two groups. Further, there were three eigenvalues remarkably different among the lines with 11.0-13.5% of amylose content compared with control group. An optimized mathematical model, which characterizes the relationships between the amylose content and RVA eigenvalue, has been established in this study. From this model, it was clearly indicated that the parameters PeT and SBV were more related to amylose content. It was concluded that the differences in amylose content not only affected the eigenvalues of RVA but also caused different RVA profiles within genetically similar cultivars. The introduction of antisense Wx gene could lead to reduce the amylose content and lay theoretical foundation for quality improvement in rice breeding programs. 展开更多
关键词 antisense Wx gene amylose content RVA profile RICE
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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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Determination of Ge content in high concentration Ge-doped Czochralski Si single crystals by FTIR 被引量:1
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作者 JIANG Zhongwei ZHANG Weilian NIU Xinhuan 《Rare Metals》 SCIE EI CAS CSCD 2005年第3期226-228,共3页
SiGe single crystals with different Ge concentrations were measured by Fourier transform infrared (FTIR) spectroscopy at room temperature (RT) and 10 K. A new peak appears at the wave number of 710 cm^-1 and the s... SiGe single crystals with different Ge concentrations were measured by Fourier transform infrared (FTIR) spectroscopy at room temperature (RT) and 10 K. A new peak appears at the wave number of 710 cm^-1 and the spectroscopy becomes clearer with an increase in Ge content. The absorption strength and wave sharp of the 710 cm^-1 peak are independent of temperature. The relation of the absorption coefficient amax, the band width of half maximum (BWHM) Wit2 of the 710 cm^-1 peak, and the Ge concentration is determined with the Ge content obtained by SEM-EDX. The conversion factor is k = 1.211 at 10 K. Therefore, the Ge content in high concentration Ge doped CZ-Si single crystals can be determined by FTIR. 展开更多
关键词 SiGe single crystal Ge content FTIR Czochralski method
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Determination of the Contents of Seven Chemical Components in Vidal Grape by Quantitative Analysis of Multi-components by Single Marker(QAMS) 被引量:1
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作者 Shizhao XU Fei QI +2 位作者 Yalin XI Ling WU Weijia SUN 《Agricultural Biotechnology》 CAS 2020年第6期131-135,共5页
[Objectives]This study was conducted to establish a method of quantitative analysis of multi-components by single marker(QAMS)for the simultaneous determination of such seven chemical components as gallic acid,epicate... [Objectives]This study was conducted to establish a method of quantitative analysis of multi-components by single marker(QAMS)for the simultaneous determination of such seven chemical components as gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin and caffeic acid in Vidal grape.[Methods]The high performance liquid chromatography was carried out using a COSMOSIL C18-MS-II column(4.6 mm×250 mm,5μm)with the mobile phase acetonitrile-2%acetic acid aqueous solution(gradient elution)at a flow rate of 1.0 ml/min.The detection wavelength was 280 nm,and the column temperature was 25℃.Using caffeic acid as an internal reference,the relative correction factors between it and other six to-be-detected components,and the contents of the seven components were calculated using the correction factors.The established was compared the results with the external standard method to verify the feasibility and accuracy of the method.[Results]The seven components had a good linear relationship in the ranges of 1.060-10.60,1.419-14.19,1.062-10.62,0.2950-2.950,0.1019-1.019,0.2014-2.014,and 0.1498-1.498μg,respectively,and the relative correction factors of gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid and rutin were 0.9760,0.7806,0.3277,1.640,1.161,2.778,respectively.There was no significant difference between the results of the QAMS method and the external standard method.[Conclusions]The QAMS method using caffeic acid as an internal reference is accurate and feasible,and provides a reliable method for the quality evaluation of Vidal ice grape. 展开更多
关键词 High performance liquid chromatography Vidal grape content determination Polyphenol compounds
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