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“从茶叶中提取咖啡因”微型实验的改进 被引量:10
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作者 张占吉 穆素珍 +1 位作者 许明远 闫宏远 《保定师范专科学校学报》 2004年第4期26-27,共2页
论了咖啡因提取采用微型化后所用装置及提取方法的改进.
关键词 咖啡因提取 索氏提取器 实验装置 茶叶
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5种海洋动物脂类提取物的抑菌试验 被引量:5
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作者 张明凤 黄彬 +2 位作者 张锋 彭玉玲 陈寅山 《福建师范大学学报(自然科学版)》 CAS CSCD 2001年第2期115-117,共3页
取 5种海洋动物 ,用索氏提取的方法提取脂类物质 .提取物用纸片法对 3种细菌和 2种真菌的生长进行抑制试验 .结果表明 :5种海洋动物的脂类提取物对 3种细菌和 2种真菌表现出一定的抑制作用 ,其中 ,对细菌的抑制效果达 80 % ,对真菌的抑... 取 5种海洋动物 ,用索氏提取的方法提取脂类物质 .提取物用纸片法对 3种细菌和 2种真菌的生长进行抑制试验 .结果表明 :5种海洋动物的脂类提取物对 3种细菌和 2种真菌表现出一定的抑制作用 ,其中 ,对细菌的抑制效果达 80 % ,对真菌的抑制效果达 60 % 展开更多
关键词 海洋动物 索氏提取 脂类物质 抑菌作用 抗菌活性 软件动物 抑制试验
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Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques 被引量:9
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作者 LANGYinhai CAOZhengmei NIEXinhua 《Journal of Ocean University of China》 SCIE CAS 2005年第2期173-176,共4页
The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake ... The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented. 展开更多
关键词 organochlorine pesticides Taihu Lake sediments soxhlet extraction ultrasonic extraction accelerated solvent extraction
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Discoursing on Soxhlet extraction of ginseng using association analysis and scanning electron microscopy 被引量:6
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作者 Yuan Yue Zi-Dong Qiu +4 位作者 Xian-You Qu Ai-Ping Deng Yuan Yuan Lu-Qi Huang Chang-Jiang-Sheng Lai 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第5期312-317,共6页
Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In t... Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In this study, Panax ginseng was selected as a model sample. Soxhlet extraction by means of a water bath, which has always been neglected, was identified as a novel key factor in the poor repeat- ability in different batches of Soxhlet extraction, as it can affect the siphon times and reflux time, which have been positively correlated with the ginsenoside contents. By substituting round bottom flasks in the same column, the relative standard deviation of the most fluctuated compound, ginsenoside Rbl, was decreased from 24.6% to 5.02%. Scanning electron microscopy analysis confirmed that the breakdown of the surface of the ginseng powder in the Soxhlet extraction led to a better dissolution of ginsenosides, indicating that chloroform may promote the extraction of ginsenosides by disrupting the cell structure. Moreover, 70% methanol was regarded as the better solvent for extracting the ginsenosides. Overall, this work offers a practical and effective protocol for improving the accuracy and repeatability of Soxhlet extraction methodology for ginsenosides and other analytes. 展开更多
关键词 GINSENG GINSENOSIDES soxhlet extraction REPEATABILITY Siphon times
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Mechanism of catalytic hydropyrolysis of sedimentary organic matter with MoS_2 被引量:6
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作者 He Kun Zhang Shuichang +2 位作者 Mi Jingkui Chen Jianping Cheng Lei 《Petroleum Science》 SCIE CAS CSCD 2011年第2期134-142,共9页
MoS2 was used as an efficient catalyst for hydropyrolysis (Hypy) of three samples of sedimentary organic matter with different maturities. Through comparison with Soxhlet extraction (SE), it was found that MoS2 ca... MoS2 was used as an efficient catalyst for hydropyrolysis (Hypy) of three samples of sedimentary organic matter with different maturities. Through comparison with Soxhlet extraction (SE), it was found that MoS2 catalytic Hypy can remarkably promote the yields of total chloroform extracts, saturates, aromatics, hopanes and steranes. In addition, the difference of biomarker parameters indicated that isomerization of covalently-bound biomarkers is much more difficult than their free counterparts. Meanwhile, the high conversion of total organic carbon (TOC) in MoS2 catalytic Hypy of organic matter proved that the presence of dispersed molybdenum sulfide accelerated the breaking of C-C bonds and the release of hydrocarbons. To address the catalytic mechanism, a series of control experiments based on free Hypy and catalytic Hypy were conducted. The results showed that the calculated atomic ratio of carbon conversion/hydrogen conversion for catalytic Hypy was much larger than the presumed value of 1/2, indicating that intensive hydrogenation took place and significantly influenced the distribution of liquid products. Analysis of stable hydrogen isotope data, infrared spectra and m/z 83 ion chromatograph of the saturate fraction further confirmed this hypothesis. The difference of S content changing (AS) between catalyst-free Hypy and catalytic Hypy, and the thermal characteristics of the catalyst, indicated that active H2S was definitely generated and it probably initiated free radical reactions in the early stage of hydropyrolysis of organic matter. 展开更多
关键词 Catalytic hydropyrolysis molybdenum disulfide KEROGEN COAL soxhlet extraction biomarkers
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贵州野生蕨菜中总黄酮含量的测定与分析 被引量:8
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作者 卢文芸 许文琴 +1 位作者 于锡忠 李洪庆 《贵州农业科学》 CAS 北大核心 2012年第5期47-49,共3页
为野生蕨菜资源的开发与利用提供科学依据,用分光光度法对野生蕨菜中总黄酮类化合物的含量进行了测定。结果表明:冬季野生蕨菜,根状茎总黄酮化合物含量最高,达6.09%;叶片和叶柄总黄酮化合物含量相对较少,分别为2.95%和3.09%。春季野生蕨... 为野生蕨菜资源的开发与利用提供科学依据,用分光光度法对野生蕨菜中总黄酮类化合物的含量进行了测定。结果表明:冬季野生蕨菜,根状茎总黄酮化合物含量最高,达6.09%;叶片和叶柄总黄酮化合物含量相对较少,分别为2.95%和3.09%。春季野生蕨菜,根状茎与叶片总黄酮化合物含量较高,分别为5.80%和5.54%;叶柄总黄酮化合物含量较低,仅为2.28%。春、冬季节采收的野生蕨菜均以根状茎总黄酮化合物含量最高。 展开更多
关键词 野生蕨菜 总黄酮 索式脱脂法 分光光度法 贵州
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Gas chromatography-mass spectrometry analysis of different organic crude extracts from the local medicinal plant of Thymus vulgaris L 被引量:5
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作者 Laila Salim Al Hashmi Mohammad Amzad Hossain +2 位作者 Afaf Mohammed Weli Qasim Al-Riyami Jamal Nasser Al-Sabahi 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第1期69-73,共5页
Objective:To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L(T.vulgaris)by gas chromatography-mass spectrometry(GC-MS).Methods:The shad... Objective:To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L(T.vulgaris)by gas chromatography-mass spectrometry(GC-MS).Methods:The shade dried leaves powder was extracted with methanol by using Soxhlet extractor.Methanol crude extracts of T.vulgaris and the derived fractions of hexane,chloroform,ethyl acetate and butanol were obtained.Results:Qualitative analyses of various organic crude extracts of T.vulgaris by using GC-MS showed that there were different types of high and low molecular weight compounds.Most of the isolated and identified compounds by GC-MS in the crude extracts are basically biologically important.Further,the T.vulgaris leaf possessed certain characteristics that can be ascribed to cultivation on a domestic plantation.The crude extracts were prepared from the powder leaves of T.vulgaris for respective compounds can be chosen on the basis of above GC-MS analysis.Conclusions:All the major compounds were identified and characterized by spectroscopic method in different organic crude extracts of T.vulgaris are biologically active molecules.Thus the identification of a good number of compounds in various crude extracts of T.vulgaris might have some ecological role. 展开更多
关键词 THYMUS VULGARIS L Preparation CRUDE extracts soxhlet EXTRACTOR GC-MS analyses
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高效液相色谱法检测土壤中的壬基酚 被引量:7
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作者 邓琴 翟丽芬 《环境科学与管理》 CAS 2010年第8期82-84,共3页
建立一种土壤中壬基酚的提取和含量测定方法。土壤样品经二氯甲烷索氏提取、旋转蒸发仪浓缩蒸干后,用色谱流动相溶解。以色谱甲醇与高纯水(体积比为85:15)为流动相,经C18色谱柱分离,在检测波长277nm进行紫外光检测。土壤样品中4-... 建立一种土壤中壬基酚的提取和含量测定方法。土壤样品经二氯甲烷索氏提取、旋转蒸发仪浓缩蒸干后,用色谱流动相溶解。以色谱甲醇与高纯水(体积比为85:15)为流动相,经C18色谱柱分离,在检测波长277nm进行紫外光检测。土壤样品中4-壬基酚的捡出限为20ng/g,4-壬基酚混合标准检测相对标准偏差范围在2.39%-4.56%之间。加入标准溶液后,土壤中壬基酚的加标回收率为98.73%~101.78%,标准偏差小于2.97%。该方法简便快速,灵敏可靠,适用于土壤样品中环境类激素4-壬基酚的含量检测。 展开更多
关键词 高效液相色谱 4-壬基酚 索氏提取 环境科学
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甘草多糖提取工艺研究 被引量:7
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作者 王亚红 曲小姝 祝波 《吉林化工学院学报》 CAS 2011年第5期37-40,共4页
用索氏提取法提取甘草多糖.采用苯酚—硫酸法测定总多糖的含量,以浸膏得率及多糖质量分数为综合考察指标,对索式提取法提取甘草多糖进行了工艺条件优化.甘草多糖提取的最佳工艺条件为:甘草目数30目,加9倍量水,提取3 h;醇沉生药:水提液... 用索氏提取法提取甘草多糖.采用苯酚—硫酸法测定总多糖的含量,以浸膏得率及多糖质量分数为综合考察指标,对索式提取法提取甘草多糖进行了工艺条件优化.甘草多糖提取的最佳工艺条件为:甘草目数30目,加9倍量水,提取3 h;醇沉生药:水提液体积比为1 1,加4倍量95%乙醇.工艺验证实验结果理想,水提取工艺综合评分97.61,RSD=1.81%;醇沉淀工艺综合评分97.39,RSD=1.81%. 展开更多
关键词 甘草 甘草多糖 索氏提取
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Effect of Temperature on Extraction of Castor Oil from Castor Seeds Using Potential Green Solvents
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作者 Zinhle Innocentia Mkhize Peterson Thokozani Ngema Suresh Ramsuroop 《Advances in Chemical Engineering and Science》 2023年第4期301-317,共17页
Extraction of castor oil from castor seeds was investigated using different green solvents which include d-limonene, p-cymene, α-pinene, ethanol, and furfural at the temperature range of (323 - 413) K. The Soxhlet ex... Extraction of castor oil from castor seeds was investigated using different green solvents which include d-limonene, p-cymene, α-pinene, ethanol, and furfural at the temperature range of (323 - 413) K. The Soxhlet extraction method was employed to investigate the effect of temperature at atmospheric pressure. The focus of the study was to investigate a potential green solvent that can produce the high yields compared to the traditional solvent (hexane). The results show that at the average time of 3 hours and 30 minutes, the castor oil yield for green solvents were ranked as furfural (47.13%) > ethanol (45.37%) > p-cymene (39.15%) > d-limonene (39.13%) > α-pinene (38.11%). These castor oil yields were obtained at optimum temperatures for each green solvent. The castor oil yields were compared to the yield of hexane (31.36%) at same average time. The green solvents were recovered by using simple distillation, except furfural which was difficult to be recovered. 展开更多
关键词 Castor Oil YIELD soxhlet Extraction Green Solvents
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两种脂肪测定方法的对比及改进 被引量:6
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作者 陈银珊 靳权 何维 《广东化工》 CAS 2016年第7期189-189,198,共2页
食品中脂肪含量的测定是食品质量管理的一项重要工作,是评价产品品质,组织生产的重要依据。文章对脂肪测定的两种方法做了详细的阐述、对比,并对目前的一些改进方法做了介绍,以期对食品脂肪的检测工作有所帮助。
关键词 脂肪 索氏 酸水解
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二噁英提取方法的比较 被引量:3
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作者 谷月玲 陈彤 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期122-124,共3页
Labeled polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs)were extracted by three different methods,i.e.,soxhlet extraction,hot extraction and accelerated solvent extraction(ASE).The PCDD/Fs were detected by... Labeled polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs)were extracted by three different methods,i.e.,soxhlet extraction,hot extraction and accelerated solvent extraction(ASE).The PCDD/Fs were detected by high resolution gas chromatography-high resolution mass spectrometry.Comparisons of the three methods were carried out by recovery of PCDD/Fs,solvent consumption and extraction time.The results showed that all of the method could extract labeled PCDD/Fs efficiently.ASE was a time saving procedure with lowest consumption of solvents compared with the other two methods. 展开更多
关键词 Polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) soxhlet extraction Hot extraction Accelerated solvent extraction(ASE) High resolution gas chromatography/high resolution mass spectrometry(HRGC/HRMS)
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Applicability of Static Supercritical Carbon Dioxide Extraction in Biogeochemical Characterization of Oil Shales 被引量:3
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作者 Hans Luik Lea Luik +2 位作者 Vilja Palu Galina Sharayeva Andre Gregor 《American Journal of Analytical Chemistry》 2014年第3期173-180,共8页
This study aimed at the assessment of applicability of static supercritical carbon dioxide extraction method (SFE) in biogeochemical characterization of oil shales as an alternative to the standard Soxhlet extration. ... This study aimed at the assessment of applicability of static supercritical carbon dioxide extraction method (SFE) in biogeochemical characterization of oil shales as an alternative to the standard Soxhlet extration. A comparative investigation on yields and compositions of the solvent soluble bitumoids and their constituents extracted from Estonian Kukersite and Dictyonema oil shales by using Soxhlet extraction method (SEM) and static CO2 supercritical fluid extraction in an autoclave at varied subpyrolysis temperatures was carried out. Resulting from TLC- and GC-MS-analyses, aliphatic and aromatic hydrocarbons and neutral oxygen compounds were separated and identified. For the first time, in the composition of the Kukersite bitumoid, homologous series of n-alkanones-3 to n-alkanones-7 were detected. The extracts obtained were similar in both group and individual composition, and geochemical parametres calculated on the basis of aliphatic hydrocarbons including that made static SFE applicable to geochemical investigation of oil shales. 展开更多
关键词 Oil SHALE Bitumoid SUPERCRITICAL EXTRACTION soxhlet EXTRACTION GEOCHEMICAL Parametres
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Chemical composition of essential oils and in vitro antioxidant activity of fresh and dry leaves crude extracts of medicinal plant of Lactuca Sativa L.native to sultanate of Oman 被引量:3
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作者 Rahma Said Salim Al Nomaani Mohammad Amzad Hossain +2 位作者 Afaf Mohammed Weli Qasim Al-Riyami Jamal Nasser Al-Sabahi 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第5期353-357,共5页
Objective:To isolate and analyse the chemical composition in the essential oils and free radical scavenging activity of different crude extracts from the fresh and dry leaves of vegetable plants of Lactuca sativa L.(L... Objective:To isolate and analyse the chemical composition in the essential oils and free radical scavenging activity of different crude extracts from the fresh and dry leaves of vegetable plants of Lactuca sativa L.(L.sativa).Methods:The essential oils and volatile chemical constituents were isolated from the fresh and dry leaves of L.sativa(lettuce)grown in Sultanate of Oman by hydro distillation method.The antioxidant activity of the crude extracts was carried out by well established free radical scavenging activity(DPPH)method.Results:About 20 chemical compounds of different concentration representing 83.07%and 79.88%respectively were isolated and identified by gas chromatography-mass spectroscopy in the essential oils isolated from the fresh and dry leaves asα-pinene(5.11%and 4.05%).γ-cymene(2.07%and 1.92%),thymol(11.55%and 10.73%),durenol(52.00%and 49.79%),α-terpinene(1.66%and 1.34%),thymol acetate(0.99%and 0.67%),caryophyllene(2.11%and 1.98%),spathulenol(3.09%and 2.98%).camphene(4.11%and3.65%),limonene(1.28%and 1.11%)representing these major chemical compounds.However,some other minor chemical constituents were also isolated and identified from the essential oil of lettuce including p-pinene,α-terpinolene,linalool,4-terpineol,α-terpineol,o-methylthymol,L-alloaromadendrene and viridiflorene.Conclusions:The chemical consliluents in the essential oils from the locally grown lettuce were identified in the following classes or groups of chemical compounds such as monoterpenes,sesquiterpenes volatile organic compounds and their oxygenated hydrocarbons.Therefore,the essential oils and the crude extracts from Omani vegetable species of lettuce are active candidates which would be used as antioxidant,antifungal or antimicrobial agents in new drugs preparation for therapy of infectious diseases. 展开更多
关键词 LACTUCA SALIVA Omani LETTUCE Clevenger apparatus Essential oil Durenol THYMOL soxhlet extractor Organic crude extracts Antioxidant activity GC-MS analyses
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蜚蠊药材质量控制方法研究 被引量:5
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作者 杨永寿 肖培云 刘光明 《时珍国医国药》 CAS CSCD 北大核心 2008年第8期1808-1809,共2页
目的建立蜚蠊药材的质量控制方法。方法采用薄层色谱法定性鉴别,色谱条件为正丁醇-醋酸-水(5:1:1).0.5%茚三酮显色剂;采用索氏提取法测定脂肪含量;水分测定法检查水分的最低控制限;分光光度法测定总氨基酸的含量,茚三酮显... 目的建立蜚蠊药材的质量控制方法。方法采用薄层色谱法定性鉴别,色谱条件为正丁醇-醋酸-水(5:1:1).0.5%茚三酮显色剂;采用索氏提取法测定脂肪含量;水分测定法检查水分的最低控制限;分光光度法测定总氨基酸的含量,茚三酮显色后检测波长为570nm。结果蜚蠊药材与对照品薄层色谱斑点清晰,易于识别,药材中脂肪的含量不得超过7.0%,水分含量不得超过12.0%,分光光度法测定总氨基酸含量,回归方程:A=0.067943C+0.009143,r=0.9999,酪氨酸含量在1.0~10.0μg范围内呈良好的线性关系。结论该方法简便易行,重复性好,可用于蜚蠊药材的质量控制。 展开更多
关键词 蜚蠊药材 薄层色谱法 索氏提取法 水分测定法 分光光度法
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不同茶叶中咖啡因的提取 被引量:5
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作者 李凡姝 张焕丽 +4 位作者 马慧 崔晓彤 王霞 刘娣 肖志刚 《农产品加工(下)》 2016年第8期33-35,共3页
采用索氏抽提法提取茶叶中的咖啡因,以95%乙醇为提取剂,利用生石灰中和乙醇提取液中含有的单宁酸,使咖啡因从提取液中游离出来,然后采用升华法使咖啡因结晶,对提取出的咖啡因样品用红外光谱进行结构鉴定,确定其成分。主要测定了市售各... 采用索氏抽提法提取茶叶中的咖啡因,以95%乙醇为提取剂,利用生石灰中和乙醇提取液中含有的单宁酸,使咖啡因从提取液中游离出来,然后采用升华法使咖啡因结晶,对提取出的咖啡因样品用红外光谱进行结构鉴定,确定其成分。主要测定了市售各类不同产地茶叶中咖啡因含量,并对其中一种茶叶——铁观音不同加工方法 (以其价位或等级作为参考)的咖啡因含量进行粗略评价。在试验过程中,对相关试验条件(如提取剂体积、升华时间等)作了初步探讨。 展开更多
关键词 茶叶 索氏抽提法 提取剂 升华法 咖啡因
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苦豆子种子中挥发油成分的分析 被引量:5
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作者 王凯 杨晋 《榆林学院学报》 2010年第2期43-46,共4页
分别采用水蒸气蒸馏法(SD)和索氏提取法(SE)对宁夏地区苦豆子种子挥发油进行了提取,利用GC/MS比较分析了挥发油的化学成分,峰面积归一法得出各化学成分在挥发油中的百分含量。SD法共分离出29个色谱峰,鉴定出27种物质,占总峰面积的91.53%... 分别采用水蒸气蒸馏法(SD)和索氏提取法(SE)对宁夏地区苦豆子种子挥发油进行了提取,利用GC/MS比较分析了挥发油的化学成分,峰面积归一法得出各化学成分在挥发油中的百分含量。SD法共分离出29个色谱峰,鉴定出27种物质,占总峰面积的91.53%;SE法共分离出28个色谱峰,鉴定出23种物质,占总峰面积的98.61%。 展开更多
关键词 苦豆子种子 挥发油 水蒸气蒸馏 索氏提取 GC/MS
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Profiling the effects of microwave-assisted and soxhlet extraction techniques on the physicochemical attributes of Moringa oleifera seed oil and proteins 被引量:1
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作者 Ngozi Maryann Nebolisa Chukwuebuka Emmanuel Umeyor +2 位作者 Uchenna Eunice Ekpunobi Immaculeta Chikamnele Umeyor Festus Basden Okoye 《Oil Crop Science》 CSCD 2023年第1期16-26,共11页
There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet ... There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet extraction(MAE and SE) techniques on the functional physicochemical quality characteristics of Moringa oleifera seed oil and proteins extracts. M. oleifera seeds were ground to fine powders and oil was extracted by microwave-assisted and soxhlet extraction techniques using petroleum ether. Quality attributes including yield percent, moisture content,iodine, saponification, specific gravity, viscosity, p H, thiobarbituric acid, acid and peroxide values were measured. Mineral and vitamin contents, chemical/functional groups, fatty acid(FA) composition, and reducing power of the oil were evaluated. Metabolomics of protein extracted from the defatted powders were analyzed by nuclear magnetic resonance(NMR). M. oleifera oil from MAE and SE methods had good yield(34.25 ± 0.0%,28.75 ± 0.0%), low moisture content(0.008 ± 0.0%, 0.011 ± 0.0%), non-drying and unsaturated, moderately saponified, less dense(0.91 ± 0.01, 0.92 ± 0.02 g m L^(-1)), had Newtonian flow, were weakly acidic, showed good content of FAs, recorded strong potential for long shelf-life, showed stability against oxidative rancidity and enzymatic hydrolysis, had very rich deposits of micro-and macro-nutrients as well as water-soluble and lipidsoluble vitamins, and functional groups in the oil were reflective of its content of long-and medium-chain triglycerides(LCT and MCT). Monounsaturated and saturated fatty acids(MUFA and SFA) were detected and the oil has excellent ferric ion reducing power. NMR metabolomic assay revealed the presence of nine essential amino acids(EAAs) in the protein extract. MAE technique is a feasible and acceptable alternative for high throughput extraction of M. oleifera oil with high yield and excellent quality attributes. The study revealed that MAE did not impart any remarkable advantage(s) on the physicochemi 展开更多
关键词 Moringa oleifera seed Oil Microwave-assisted extraction soxhlet extraction Quality attributes GC-MS assay Metabolomics Reducing power
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模型优化塔拉籽油的超临界制备工艺 被引量:5
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作者 李占君 张厚良 +3 位作者 徐宜彬 马珂 姚彦文 杨逢建 《森林工程》 北大核心 2021年第4期79-86,共8页
为研究塔拉籽油的超临界提取工艺,以单因素实验为基础,对影响油脂得率的因素进行响应面的优化,分析提取所得油脂的脂肪酸构成和理化特性。优化结果得出最佳影响因素为:60目塔拉籽粉末100 g,温度45℃,压强32 MPa,时间109 min,实际操作得... 为研究塔拉籽油的超临界提取工艺,以单因素实验为基础,对影响油脂得率的因素进行响应面的优化,分析提取所得油脂的脂肪酸构成和理化特性。优化结果得出最佳影响因素为:60目塔拉籽粉末100 g,温度45℃,压强32 MPa,时间109 min,实际操作得率的算术平均值为18.95%,预期得率19.38%,相对误差为2.2%。塔拉籽油脂肪酸类型8种,代表性不饱和脂肪酸为亚油酸,其相对含量可达65.36%。超临界酸值与索氏提取所得油脂酸值为2.899~2.993 mg/g,碘值为0.1535~0.1537 mg/g,因此塔拉籽油的不饱和程度、干燥性和氧化稳定性较好。研究结果证实了超临界提取不影响原有脂肪酸构成,并对油脂品质有改良作用,能够实现塔拉籽油的高效提取,为塔拉籽油的制备提供数据参考。 展开更多
关键词 塔拉籽油 超临界 索氏 响应面法优化 脂肪酸构成 理化性质
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Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris 被引量:2
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作者 Mohammad Amzad Hossain Khulood Ahmed Salim AL-Raqmi +2 位作者 Zawan Hamood AL-Mijizy Afaf Mohammed Weli Qasim Al-Riyami 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期705-710,共6页
Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al ... Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar,Nizwa.Sultanate of Oman.Methods:The leave sample was extracted with methanol and evaporated.Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities.The prepare hexane,chloroform,ethyl acetate,hutanol and methanol crude extracts were used for their evaluation of total phenol,flavonoids contents and phytochemical screening study.The established conventional metliods were used for quantitative determination of total phenol,flavonoids contents and phytochemical screening.Results:Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids,saponins and steroids compounds.The result for total phenol content was the highest in hutanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract.Conclusions:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases. 展开更多
关键词 THYMUS VULGARIS L. VARIOUS crude extracts PHYTOCHEMICAL screening soxhlet EXTRACTOR Total phenol Flavonoids contents.
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