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建立了超声微波酶解协同提取油茶壳中原花青素的方法。通过单因素试验,探讨了超声微波协同提取油茶壳中原花青素过程中各主要因素对原花青素提取率的影响规律。实验中发现,往提取液中加入适量纤维素酶,可显著提高原花青素的提取率。在此基础上,通过正交试验,优化并获得了超声微波酶解协同提取原花青素的最适宜条件。最适宜提取条件为:超声波频率40 KHz、微波功率200 W、提取时间60 s、料液比1∶6、提取温度50℃、0.1%纤维素酶0.5 mL、提取次数2次。在最适宜条件下,原花青素的提取率为4.46%,分别是超声提取、微波提取和超声-微波协同提取的4.0、3.3和1.8倍。本文所建立的超声微波酶解协同提取油茶壳中原花青素的方法具有简便、快速、高效和节能等优势,有利于应用推广。 相似文献
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野菊花中蒙花苷的提取及其含量的测定 总被引:1,自引:0,他引:1
以乙醇为溶剂,采用溶剂回流提取方法结合微波、超声波辅助提取野菊花中的蒙花苷,用HPLC法测定。采用正交试验法研究了野菊花中蒙花苷提取和HPLC实验条件,并比较了采用不同的微波和超声波辅助提取方式对蒙花苷提取结果的影响。结果表明,溶剂回流提取最佳条件为:提取温度80℃,回流时间2.0 h,溶剂用量40 mL。应用于安徽等产地野菊花中蒙花苷的提取分析,结果显示,广东和广西产地药材含量明显更高;在相同的实验条件下采用微波辅助提取可使蒙花苷达到较高的提取率,特别是采用微波辐射药材后再进行溶剂回流提取,提取时间可缩短一半。 相似文献
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L-半胱氨酸衍生物配体交换手性色谱固定相 总被引:13,自引:0,他引:13
应用密闭微波萃取装置对芦荟中的有效成分芦荟甙进行了微波萃取研究,并利用透射电子显微镜对微波萃取机理进行了初步探讨,讨论了不同萃取剂、溶剂浓度、萃取时间和微波功率等对提取率的影响,在萃取剂为乙醇-水体系,溶剂(乙醇)体积分数为70%、萃取时间为4min及微波功率为340W的条件下,萃取效果最佳,与索氏提取及超声波萃取法相比,本法具有萃取速度快、提取率高及溶剂用量少等特点。 相似文献
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UE/ME-GC-MS提取分析普洱茶的挥发和半挥发性成分 总被引:3,自引:1,他引:2
采用超声波提取(UE)和微波萃取(ME)两种前处理方法提取普洱茶的挥发性成分,利用气相色谱-质谱(GC-MS)联用仪进行定性检测,并加入乙酸苯乙酯作为内标进行定量分析。结果表明:两种萃取方法共鉴定出挥发性成分88种,其中超声波萃取检测出79种,微波萃取检测出69种。普洱茶的主要挥发性成分有11,14,17-二十三碳烯酸甲酯、咖啡因、棕榈酸、维生素E、β-香树脂醇、植醇等。超声波萃取法得到的提取率较高,而微波提取法耗时较短,两者各有所长,应根据需要来选择。 相似文献
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Active components from traditional Chinese medicine (TCM) are the material basis for disease treatment. Extraction, identification, and transformation are the critical processes to analyze and use the active components of TCM. Botanic TCM takes up 90 % of total Chinese crude drugs. Some active components are complex and of lower level; moreover, most of them are enveloped under plant cell wall. Traditional extraction methods such as lixiviate method, decoction, and others are often hindered by cell wall, leading to low extraction efficiency, low clearance of impurity, and other problems, which have restricted the development of TCM. This paper reviews both domestically and internationally published literatures in recent years on application of enzymatic methods in the extraction and transformation of active ingredients from TCM. Principles of enzymatic method and its application in extraction and transformation of active ingredients and in dreg recycles of TCM are introduced in detail. With the development of TCM modernization, enzymatic method applied in the domain of TCM has achieved prominent benefits, not only improving the extraction and separation rate of active ingredients from TCM and elevating the transformation level and production, but also reducing costs in the transformation of active ingredients. 相似文献
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Effect of sample handling on alkaloid and mineral content of aqueous extracts of greater celandine (Chelidonium majus L.) 总被引:4,自引:0,他引:4
The authors examined the extraction of alkaloids from the greater celandine (Chelidonium majus L.) by different methods (traditional pressing and tea making, microwave and supercritical fluid extraction). The extractants were water and propylene glycol. For comparison of the extraction methods, the yield was evaluated according to total alkaloid content measured by spectroscopy. The highest alkaloid yield was obtained by microwave extraction and by making tea. Distribution of the components was studied by thin-layer chromatography and densitometry. The concentration and the ratio of alkaloid components in extracts are significantly different depending on the extraction method. The solution obtained by supercritical fluid extraction contains coptisine and chelidonine, while berberine could be obtained by microwave extraction only. Extracts with high coptisine content were obtained by supercritical fluid extraction, followed by pressing and microwave extraction. Mineral element content of the drug and extracts was also determined by inductively coupled plasma atomic emission spectrometry. Element content (Na, Ca, Fe) was found to be highest in microwave extracts. 相似文献
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Ultrasound‐enhanced and microwave‐assisted extraction of lipid from Dunaliella tertiolecta and fatty acid profile analysis 下载免费PDF全文
Microalgal lipid is considered as a potential biodiesel resource due to its advantages compared to other bioresources. The production of biofuel from microalgae includes several stages like microalgae cultivation, biomass harvest, biomass treatment, lipid extraction, and the ultimate biodiesel synthesis. Lipid extraction is closely associated with the productivity and cost of energy production. In the present study, lipid of green algae Dunaliella tertiolecta was extracted by chemical agents with involvement of ultrasound and microwave. The optimization of experimental conditions was carried out by response surface methodology and orthogonal test design. Using the ultrasonic technique, an extraction rate of 45.94% was obtained under the optimum conditions of ultrasonic power 370 W, extraction time 5 min and liquid/solid ratio 125 mL/g. The extraction rate of 57.02% was obtained by the means of microwave assistance under the optimized conditions of extraction time 160 s, microwave power 490 W and liquid/solid ratio 100 mL/g. The comparison of the two results indicated microwave was more effective than ultrasound in extracting process. When the two techniques were utilized in combination, the optimized condition was ultrasonic power 320 W, ultrasonic time 4 min, microwave power 280 W, microwave time 120 s and liquid/solid ratio 100 mL/g, and the extraction rate was 49.97%. 相似文献
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Ying Lu Ming Ye Sheng Song Lan Li Farnaz Shaikh Junhong Li 《Applied biochemistry and biotechnology》2014,174(2):762-771
Intracellular melanin from Lachnum singerianum YM296 (LIM) was obtained by the method of microwave-assisted extraction. On the basis of single factor experiment, the optimum microwave-assisted extraction conditions of LIM using Box–Behnken design were as follows: NaOH concentration, 1.05 mol/L; ratio of raw material to liquid ratio, 1:14.72 (g/mL); microwave time, 118.70 s; and microwave power, 320 W. Under these conditions, the extraction yield of LIM was 11.08 %, and 40.43 % higher than that of extraction by alkali extraction and acid precipitation. The results showed that microwave-assisted extraction could increase the extraction yield of LIM. Three homogeneous components were fractionated from LIM by Sephadex G-15 column. LIM-a was the main homogeneous component, accounting for 75.7 % of the total content of the homogeneous components. Aged mice model were induced by injecting d-galactose, and the aged mice were given LIM-a of different dosages, respectively. The results showed that LIM-a can significantly increase body weight, thymus indexes, and spleen indexes of the aged mice; effectively elevate the levels of SOD, GSH-PX, and CAT; and decrease the level of MDA in mice liver homogenate, brain homogenate, and serum, indicating that LIM-a had significant anti-aging activity. 相似文献
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神华煤直接液化残渣超临界溶剂萃取研究 总被引:2,自引:0,他引:2
利用甲苯、苯和乙醇三种溶剂在反应釜中对神华煤直接液化残渣进行了超临界溶剂萃取,考察了压力、温度、萃取时间、溶剂/残渣比等对萃取产物收率和重质液体萃取组成的影响。结果表明,以甲苯为溶剂进行萃取时,萃取时间对重质液体产率及HS和A收率的影响不大,而温度、压力以及溶剂/残渣质量比都会影响萃取产物的产率及组成。溶剂超临界萃取过程中,有其他组分向HS组分转化,提高了HS的收率。三种溶剂中,苯显示了和甲苯相似的萃取性能,而乙醇的萃取性能相比苯和甲苯则较差,但乙醇萃取得到的重质液体中轻质组分含量高于苯和甲苯。萃取过程中,残渣中的灰分和硫分主要富集至萃取残渣中。 相似文献
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Xinsheng Fang Yingzi Wang Jianhua Wang Jin Zhang Xin Wang 《Journal of separation science》2013,36(16):2672-2679
An optimized microwave‐assisted extraction (MAE) method and RP‐HPLC method were developed for the simultaneous extraction and determination of rutin, forsythiaside A, and phillyrin in the fruits of Forsythia suspensa. The key parameters of the open‐vessel MAE process were optimized. A mixed solvent of methanol and water (70:30, v/v) was most suitable for the simultaneous extraction of the three components. The sample was soaked for 10 min before extraction. The optimized conditions were: microwave power 400 W, temperature 70°C, solvent‐to‐material ratio 30 mL/g, and extraction time 1 min. Compared to conventional extraction methods, the proposed method can simultaneously extract the three components in high yields and was proved to be a more rapid method with a lower solvent consumption. The optimized HPLC–photodiode array detection analysis was validated to have good linearity, precision, accuracy, and sensitivity. The developed MAE followed by RP‐HPLC is a fast and appropriate method for the simultaneous extraction and determination of rutin, forsythiaside A, and phillyrin in the fruits of F. suspensa. 相似文献
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Arjunic acid and arjunolic acid are main bioactive components of Terminalia arjuna stem bark and reported for various biological activities. In this study, microwave-assisted extraction (MAE) of arjunic and arjunolic acid from stem bark of T. arjuna was investigated with developed and validated HPLC-PDA method, which resulted in the isolation of a novel anticancer molecule i.e. arjunic acid. Effects of several experimental parameters, such as type and volume of extraction solvents, microwave power, microwave extraction time, on the extraction efficiencies of arjunic, and arjunolic acid from stem bark of T. arjuna were evaluated. The optimal extraction conditions identified were 5.0 g quantity of stem bark powder, 20 mL of ethyl acetate, preleaching time 10 min, microwave power 600 W, temperature 65°C, and microwave irradiation time 5 min. The results showed that MAE is a more rapid extraction method with higher yield and lower solvent consumptions than reported methods. The HPLC-PDA analysis method was developed and validated to have good linearity, precision, sensitivity, and accuracy. MAE-HPLC-PDA is a faster, convenient, and appropriate method for isolation and determination of arjunic acid and arjunolic acid in the stem bark of T. arjuna. 相似文献
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Tangbin Zou Hongfu Wu Huawen Li Qing Jia Gang Song 《Journal of separation science》2013,36(20):3457-3462
Mangiferin is the main bioactive component in mango leaves, which possesses anti‐inflammatory, antioxidative, antidiabetic, immunomodulatory, and antitumor activities. In the present study, a microwave‐assisted extraction method was developed for the extraction of mangiferin from mango leaves. Some parameters such as ethanol concentration, liquid‐to‐solid ratio, microwave power, and extraction time were optimized by single‐factor experiments and response surface methodology. The optimal extraction conditions were 45% ethanol, liquid‐to‐solid ratio of 30:1 (mL/g), and extraction time of 123 s under microwave irradiation of 474 W. Under optimal conditions, the yield of mangiferin was 36.10 ± 0.72 mg/g, significantly higher than that of conventional extraction. The results obtained are beneficial for the full utilization of mango leaves and also indicate that microwave‐assisted extraction is a very useful method for extracting mangiferin from plant materials. 相似文献
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《Analytical letters》2012,45(13):2387-2401
Abstract In this work, microwave-assisted extraction (MAE) followed by gas chromatography with flame ionization detector (GC–FID) was developed for the rapid determination of camphor and borneol in three traditional Chinese medicines (TCM): Chrysanthemi indici, Flos Chrysanthemi indici and Amomum villosum lour. The optimal MAE conditions obtained were: acetone for solvent, with solvent having sample ratio of 12:1 (v/w); microwave power of 380 W, and an irradiation time of 4 min. Method validations were also studied. To demonstrate the proposed method, ultrasonic-assisted extraction (UAE) and steam distillation (SD), followed by GC-FID, were used to analyze camphor and borneol in thethree TCMs. The close results were obtained by the three methods. The results showed that the proposed MAE–GC–FID is a simple, rapid, and reliable method for quantitative analysis of camphor and borneol in TCM, and is also a potential tool for TCM quality assessment. 相似文献
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A novel magnetic method using polystyrene modified magnetic nanoparticles to perform thermoheadspace extraction was successfully developed for extraction and preconcentration of volatile organic components in dry Traditional Chinese Medicine(TCM) based on gas chromatography-ion trap/mass spectrometry with a Chromato Probe direct sample introduction device. The dried fruit of Amomum testaceum Ridl. was used as the object TCM. The optimum parameters of headspace magnetic solid-phase extraction were investigated, in which desorption solvent ethyl acetate played a key role in this method,and the headspace extraction temperature of 90℃ and the headspace extraction time of 15 min finally decided. Headspace solid-phase microextraction method was also used to analyze volatile compounds in the TCM to compare with the proposed method. The results show that 60 components were identified totally by two methods; most of the low boiling point chemical compounds are isolated by this new method. In this work, an environmental-friendly and cheap analytical method was established, and a new approach to analyze volatile compounds in dry Traditional Chinese Medicine was also provided. 相似文献