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以超声提取法提取蒲公英有效成分,选择总黄酮、咖啡酸、绿原酸和菊苣酸为评价指标,结合AHP-CRITIC法计算各指标权重;在单因素试验的基础上,利用Box-Behnken法优化蒲公英超声提取工艺。实验结果表明超声提取法提取蒲公英的最优提取工艺参数为:液料比5∶1,甲醇浓度60%,提取时间26 min,在此工艺条件下预测综合评分为73.26,验证实验所得综合评分为74.13±2.63,RSD为3.55%。本研究优化的蒲公英超声提取工艺适合于蒲公英中总黄酮、咖啡酸、绿原酸和菊苣酸的提取,其工艺稳定、可靠,可为蒲公英资源的开发和利用提供参考。 相似文献
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银杏根中黄酮类化合物的分离分析 总被引:4,自引:1,他引:4
采用丙酮浸泡、回流从银杏根中提取得到黄酮,以HPLC法分离测定其中的槲皮素含量。实验结果表明:银杏根黄酮存在槲皮素甙,不含山奈酚、异鼠李素等物质。 相似文献
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采用超声波辅助提取法,优化西府海棠花朵中蛋白质的提取工艺条件,并在最佳工艺条件下研究了西府海棠花朵中蛋白质含量的动态变化。在单因素实验基础上,采用正交实验对蛋白质的主要提取工艺参数进行优化,结果为:采用pH=10的Tris-HCl提取液、液料比为70∶1(mL/g),在30℃、400 W下超声提取120 min。在该最佳提取工艺条件下,测得开花2周的花朵中蛋白质含量最高,提取率为0.023 5;开花3周的花朵中蛋白质含量最低,提取率仅为0.004 48。说明开花2周的西府海棠花的利用价值最高。该实验可作为农林院校4~5学时的分析化学实验课的综合实验。 相似文献
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采用超临界CO2法、超声波辅助提取法和索氏提取法提取山茶籽油,对它的理化指标、脂肪酸组成进行测定,并对茶粕有效成分进行分析。研究表明,超临界CO2法和超声波法提油率高,环保安全性和工艺效率好;索氏法提取的油茶籽油酸值过大;从茶粕有效成分含量来看,超声波辅助提取法更优。综合考虑3种提取方法,超声波辅助提取山茶油品质最优。 相似文献
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建立一种高效提取鹿茸中雌二醇、雌三醇和睾酮等18种性激素的方法.采用超声波提取法进行提取,液相色谱-串联质谱定性,以回收率为评价指标,分别考察提取溶剂、提取剂用量和提取时间对18种性激素提取效率的影响,并以提取效率实验对建立的方法加以验证.提取溶剂为甲醇,用量为10 m L,超声波提取时间为20 min时,利用优化的超声提取操作步骤进行提取效率实验,18种性激素回收率为73%~116%,实验结果表明在该条件下的超声波提取法快速、准确,重现性好,可同时有效提取鹿茸中的18种性激素,为鹿茸及其制品中性激素前处理提供参考方法. 相似文献
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人参中总皂甙的超声波快速提取方法研究 总被引:7,自引:0,他引:7
建立了人参中总皂甙超声波半微量快速提取方法,与索氏提取法相比,此法提取时间由索氏法的1-2个工作日缩短到30min,节省大量试剂,综合提取效率提高数十倍,与索氏提取法对照分析表明,此法可完全满足人参中总皂甙的快速测定要求。 相似文献
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对比酸水浸提法、醇提取法、索氏提取法的提取率,探讨博落回中总生物碱的最佳提取方法。从提取率、生物碱含量、有机溶剂消耗方面对酸水浸提提、乙醇提取以及索氏提取等方法的比较得出以下结论:索氏提取法中有机溶剂的回收率是最高的,酸水浸提法次之,醇提取法对原料的利用率相对来说是最低的。 相似文献
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采用微波辅助提取方法,以提取剂浓度、pH值、液固比、微波提取时间、温度等为考察因素,并以提取物中总鞣质的提取率为评价指标,使用磷钼钨酸-干酪素分光光度法为定量测定方法,在单因素实验的基础上,通过正交实验优化翻白草中鞣质的提取工艺.实验结果表明,最佳提取条件为:使用70%甲醇作为提取剂、液固比40∶1、提取液pH为8.0、提取温度为40℃、提取时间为10 min.还对翻白草不同部位(根、茎、叶)的鞣质含量进行分析,发现根部中鞣质的含量最大,其次为茎和叶.此外,采用高效液相色谱法对翻白草中鞣质的种类进行定性分析. 相似文献
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Focused microwave aqueous extraction of chlorophenols from solid matrices and their analysis by chromatographic techniques 总被引:2,自引:0,他引:2
Ganeshjeevan R Chandrasekar R Sugumar P Kadigachalam P Radhakrishnan G 《Journal of chromatography. A》2005,1069(2):275-280
Open-vessel focused microwave (FMW) extraction with a purely aqueous carbonate solution was used for the extraction of chlorophenols from various solid matrices. After SPE on C18-bonded silica, the analytes were determined as such by LC-UV or, as their acetyl derivatives, by GC-ECD. The FMW aqueous extraction is efficient and rapid and no organic solvents are used. PCP was detected in several solid samples, with recoveries of 101-115% (RSD, 2-4%) relative to Soxhlet extraction. Similar recoveries were obtained for the other chlorophenols for spiked samples. 相似文献
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超声辅助液液萃取法提取烟用香精成分的研究 总被引:1,自引:0,他引:1
采用超声辅助液液萃取法(ULLE)提取某品牌烟用香精成分,GC-MS对其进行分析,研究了不同萃取剂、萃取时间和萃取温度对分析结果的影响,初步确定了最佳条件为:以二氯甲烷为萃取剂,饱和NaCl溶液作水相,室温下超声萃取5 min.又分别与同时蒸馏萃取法(SDE)和传统的液液萃取法(LLE)作以比较,对ULLE法和SDE法鉴定出的化学成分、重现性和定量值进行了对比.结果表明:超声辅助液液萃取具有操作简便、快速、节能、萃取效率高、重现性好等特点,适合于烟用香精成分的提取. 相似文献
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Mohammadkazem Ramezani Nigel Simpson Danielle Oliver Rai Kookana Gurjeet Gill Christopher Preston 《Journal of chromatography. A》2009,1216(26):5092-5100
Extraction and quantification of herbicide residues from soil are important in understanding the behaviour of persistent herbicides. This research investigated extraction and clean-up methods for imidazolinone herbicides from soil and soil amended with organic material. A series of solvent mixes, pH conditions and sorbents was tested. Across three imidazolinone herbicides: imazapyr, imazethapyr and imazaquin, 0.5 M NaOH extraction gave greater than 90% recovery from soil samples; however, 0.5 M NaOH:MeOH (80:20) resulted in higher recovery for imazaquin, but not for the other two herbicides. Of the sorbents tested, the use of chromatographic mode sequencing using C18 and SCX sorbents provided consistent high (>85%) recovery of all three herbicides from soil and separation of the herbicides from other soil components by high performance liquid chromatography (HPLC). These two methods will allow high recovery of these imidazolinone herbicides from soil and have the ability to detect these herbicides without interference from other soil components. 相似文献
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Supercritical fluid extraction (SFE) provides for the first time a viable option to conventional and widely used Soxhlet extraction. The ability to change the solvating power of a single supercritical fluid by changing its density is an exceedingly attractive feature. An environmentally safe alternative such as supercritical carbon dioxide to organochlorine solvents which are widely used today in many government and industrial analytical laboratories for sample preparation is desirable. SFE may also constitute a viable alternative to other popular sample preparation techniques such as liquid-liquid extraction, solid phase extraction and purge/trap. Much research, however, must be done in order to understand, optimize and apply this technology. For example, (a) automation of extraction, (b) matrix effects, (c) new fluids/modifiers/additives, (d) trapping efficiency, (e) recovery of extracted analytes, and (f) extraction kinetics are some areas which need a greater understanding. This review is concerned with many of these topics as they relate to trace organic analysis wherein SFE is the primary sample preparation technique. 相似文献
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Comparison of alternative and conventional extraction techniques for the determination of zearalenone in corn 总被引:1,自引:0,他引:1
Naturally contaminated corn samples of different origin were extracted using two conventional techniques (blending and shaking) and three alternative approaches (ultrasonic extraction, accelerated solvent extraction, and microwave-assisted extraction). Use of the same extraction mixture for all trials enabled the efficiency of the various extraction techniques to be compared. Extracts were filtered and directly analyzed by LC–ESI–MS, without further clean-up. The yield from the alternative extraction techniques showed efficiency to be higher than for conventional techniques. In particular, microwave-assisted extraction was slightly superior to other techniques. 相似文献
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Muhammad Modassar A. N. Ranjha Rabia Kanwal Bakhtawar Shafique Rai Naveed Arshad Shafeeqa Irfan Marek Kieliszek Przemysaw ukasz Kowalczewski Muhammad Irfan Muhammad Zubair Khalid Ume Roobab Rana Muhammad Aadil 《Molecules (Basel, Switzerland)》2021,26(16)
Different parts of a plant (seeds, fruits, flower, leaves, stem, and roots) contain numerous biologically active compounds called “phytoconstituents” that consist of phenolics, minerals, amino acids, and vitamins. The conventional techniques applied to extract these phytoconstituents have several drawbacks including poor performance, low yields, more solvent use, long processing time, and thermally degrading by-products. In contrast, modern and advanced extraction nonthermal technologies such as pulsed electric field (PEF) assist in easier and efficient identification, characterization, and analysis of bioactive ingredients. Other advantages of PEF include cost-efficacy, less time, and solvent consumption with improved yields. This review covers the applications of PEF to obtain bioactive components, essential oils, proteins, pectin, and other important materials from various parts of the plant. Numerous studies compiled in the current evaluation concluded PEF as the best solution to extract phytoconstituents used in the food and pharmaceutical industries. PEF-assisted extraction leads to a higher yield, utilizes less solvents and energy, and it saves a lot of time compared to traditional extraction methods. PEF extraction design should be safe and efficient enough to prevent the degradation of phytoconstituents and oils. 相似文献
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The stability of Ochratoxin A during its extraction using different extraction techniques has been evaluated. Microwave-assisted extraction and pressurised liquid extraction, in addition to two other reference methods of extraction, i.e. ultrasound-assisted and magnetic stirring-assisted extraction, were evaluated. The effect of extraction temperature using the cited techniques was checked.The results show that Ochratoxin A can be extracted using microwave-assisted extraction at temperatures up to 150 °C without degradation. Pressurised liquid extraction can be used at temperatures up to 100 °C, for extraction times of less than 30 min. Further, both ultrasound-assisted extraction and magnetic stirring extraction can be applied at temperatures up to 65 °C.High-performance liquid chromatography combined with fluorescence detection using a Chromolith RP-18e column at a flow rate of 5 mL min−1 was used to quantify the Ochratoxin A. The retention time for the Ochratoxin A was 1.3 min. The limits of detection (LOD) and of quantification (LOQ) were 0.03 and 0.10 μg L−1, respectively. 相似文献
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In developing a method for possible low level isotopic enrichment, which uses to advantage the equilibrium isotope effect
observed during U(1V)-U(VI) electron exchange reaction in sulphate solutions, details of a solvent extraction process involving
high concentration of a mixture of U(IV) and U(VI) and at low acid concentrations, are described. The extraction behaviour
of uranium under these conditions is discussed. During the extraction with amines, U(IV) tended to get oxidised in sulphate
solutions. 相似文献