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1.
《云南化工》2016,(1):15-18
研究了超声波辅助提取法提取天麻中氨基酸的工艺条件。试验以氨基酸的提取率为考查指标,以提取时间、温度、乙醇体积分数和料液比4个因素进行单因素和正交实验,得到最优工艺条件为:提取时间60 min、温度45℃、乙醇体积分数60%、料液比1∶40 g/m L。在此条件下,对贵州省德江县不同品种天麻的氨基酸含量进行了测定。  相似文献   

2.
《云南化工》2017,(8):34-37
以昭通天麻中天麻素和浸出物含量为指标,考察了不同提取方法、溶剂、天麻粒径、料液比、提取次数对天麻中天麻素和浸出物含量的影响,经过实验得出50%乙醇、1:25料液比、50目粒径、沸水浴回流提取2次为最佳提取条件,测定出昭通天麻干燥块茎中天麻素含量为0.43%,浸出物为18.18%。  相似文献   

3.
《分离科学与技术》2012,47(10):1433-1439
An ultrasonic probe was introduced into the kettle of subcritical water extraction device to extract volatile oil from Lithospermum erythrorhizon. The effect of temperature, pressure, ultrasonic power, and frequency on the extraction yield was studied. Gas chromatography-mass spectrometry (GC-MS) was applied to the analysis of the compositions of volatile oil. The mechanism of ultrasonic enhanced subcritical water extraction (USWE) was discussed. The results showed that the ultrasound-assisted enhancement effect of 20 KHz was better than that of 36 KHz and increased with output power (0 ~ 250 W). The subcritical water extraction yield increased from 1.87% to 2.39% via ultrasonic oscillation (250 W, 20 KHz) at a temperature of 160°C and a pressure of 5 MPa in the 25-minute extraction. Nineteen components were identified chiefly consisting of 18 carbon unsaturated fatty acid methyl esters, hexadecanoic acid methyl ester and pentadecane. Mechanism of USWE was cavitation and mechanical effect.  相似文献   

4.
微波-超声波协同萃取银杏黄酮的工艺研究   总被引:4,自引:0,他引:4  
唐仕荣 《云南化工》2007,34(3):13-16
以银杏叶为材料,研究了乙醇浓度、微波功率、微波处理时间、料液比、银杏叶粉碎颗粒大小以及微波-超声波协同作用对银杏黄酮提取效率的影响。结果表明微波处理,微波-超声波协同处理可以显著提高银杏黄酮的提取率。确定了最佳的微波处理条件:70%乙醇为萃取液,料液比1∶20,粉末颗粒80目,微波功率50W,微波处理时间4 m in,处理后水浴回流提取2 h所得提取液的黄酮提取率达到81.76%,比直接水浴提取提高了1.3倍,微波-超声波协同处理的黄酮提取率达到83.54%。  相似文献   

5.
利用超声萃取和回流萃取方法进行单因素实验,选取提取温度、超声时间和乙醇体积分数为影响因子,应用响应面法(RSM)优化大豆荚壳异黄酮的提取条件。结果表明,大豆荚壳异黄酮优化浸提条件为:提取温度83℃、乙醇体积分数为84%、超声时间30min、大豆荚壳颗粒150μm、液料比25:1、回流萃取时间90min、超声功率108W,大豆荚壳总异黄酮的得率为3.5mg/g。响应面法大豆荚壳总异黄酮的提取条件优化合理可行,为提高大豆荚壳总异黄酮的提取率提供了依据。  相似文献   

6.
In this paper, the extraction of ferulic acid, a pharmacologically active ingredient from the root of Angelica sinensis with ultrasonic extraction was investigated. Percolation and supercritical fluid extraction (SFE) were also employed to make comparisons with ultrasonic extraction. Three variables, which including the concentration of solvent, the ratio of solvent volume to sample (mL/g), and extraction time, were found to have great influence on ultrasonic extraction. The optimum extraction conditions were using pure ethanol with a ratio of solvent volume to sample 8:1 (mL/g) and extraction time of 30 min. Under the optimum extraction conditions, the extraction yield could reach 6.5% mass fraction, which was higher than that of SFE process with ethanol as co‐solvent and nearly a content of ferulic acid 1.0%; both the yield and the content of ferulic acid were higher than those obtained by percolation. Moreover, the time of ultrasonic extraction was significantly shortened. Overall, Ultrasonic extraction was shown to be highly efficient in the extraction of ferulic acid from Angelica sinensis.  相似文献   

7.
《分离科学与技术》2012,47(2):289-299
ABSTRACT

Phenolic compounds were extracted from pistachio hull using microwave-assisted solvent extraction (MASE). The effects of four parameters, microwave power, extraction time, solvent to sample ratio, and ethanol concentration were evaluated. The extraction conditions were optimized by response surface methodology to enhance the total phenolic content (TPC). Optimal conditions were found as 140 W microwave power, 4.5 min extraction time, 19:1 (v/w) solvent to sample ratio, and 56% ethanol concentration to get maximum TPC (62.24 mg GAE/g dry hull). Also, MASE was compared with conventional solvent extraction (CSE) and MASE gave higher TPC, yield, and antioxidant activity.  相似文献   

8.
A novel method using ethanol and ultrasound to extract oil from cream obtained from enzyme-assisted aqueous extraction of soybean oil was developed. To evaluate the relationships between operating variables and free oil yield and to maximize the free oil yield, response surface methodology was introduced in this work. The developed regression model was fitted with R 2 = 0.9591. Optimized variables were: ethanol concentration of 73 %, ethanol addition volume of 0.55 L/kg, ultrasound power of 427 W, ultrasound time of 47 s, and ultrasound temperature of 53 °C. The free oil yield from the cream under the above conditions was 92.6 ± 3.4 %. Scanning electron microscopy (SEM) was used to evaluate the effect of ultrasonic treatment on ethanol-treated cream, and the SEM images clearly showed that the ultrasound treatment affected dispersing and fracturing of the microstructure of ethanol-treated cream.  相似文献   

9.
The extraction of ferulic acid, a pharmacologically active ingredient from the root of Ligusticum chuanxiong, with ultrasonic extraction was investigated. Percolation and supercritical fluid extraction (SFE) were employed to make comparisons with ultrasonic extraction. Three variables, which included the concentration of solvent, the ratio of solvent volume/sample (mL/g), and extraction time, were found to have a great influence on ultrasonic extraction. The optimum extraction was with pure ethanol with a solvent volume/sample ratio 8:1 (mL/g) and extraction time of 30 min. Under the optimum extraction conditions, the extraction yield could reach 8.8% which was higher than that using SFE with ethanol as co-solvent and a content of ferulic acid of 0.7%; both the yield and the content were higher than those obtained by percolation. Ultrasonic extraction significantly shortened the time required for the extraction process. Overall, ultrasonic extraction was shown to be highly efficient in the extraction of ferulic acid from Ligusticum chuanxiong.  相似文献   

10.
A modified ultrasound-assisted extraction (MUAE) method and an HPLC technique were developed to identify and quantify simultaneously the amount of oleanolic acid (OA) and ursolic acid (UA) in Scutellaria barbata D. Don. The optimal conditions for MUAE were observed when the particle size was 0.2–0.5 mm, the duty cycle was 75%, the extraction temperature was 55°C, the ratio of solvent to raw material was 12.0:1 (mL:g), the ethanol concentration was 60%, and the extraction time was 25 min. Compared to the traditional extraction method, MUAE reduced the extraction time, extraction temperature, and solvent consumption and achieved superior yields of OA and UA. Furthermore, the combined MUAE-HPLC method was successfully applied for the first time to investigate and compare the amounts of OA and UA in samples obtained from different geographical regions.  相似文献   

11.
In this work, solvent composition effects on the average particle size and polydispersity of the commercial perfluorinated sulfonic acid (PFSA) membrane, i.e., Flemion®, in different solution mixtures were studied. Dynamic light scattering experiments were employed to determine the aggregate sizes of dispersed PFSA polymers in different water/alcohol solutions. The particle size distribution of the solute was analyzed and discussed for different solvent–solute systems. As the solvent gets more compatible with the Flemion®, the particle size reduced. Increasing the water content in propanol/water mixture increased the average particle size of the solute. Comparing three solution mixtures shows that the mean particle size increased as the solvent was changed in the order of ethanol, methanol and propanol. Differential scanning calorimetry (DSC) tests were conducted on the films obtained by recasting from different solution compositions. The results of DSC tests were used to investigate the water absorption and other thermal behavior. Structural properties such as equivalent weight of the polymer, free volume and the degree of aggregation of ionic groups or size of the clusters can influence the water uptake. DSC test results showed four different endothermic peaks which can be attributed to removal of surface and intergrain structural absorbed water, melting of crystalline segments and thermal degradation of the polymer, respectively.  相似文献   

12.
《分离科学与技术》2012,47(18):2779-2785
Ultrasonic-assisted extraction was applied to extract oxyresveratrol from cultured black mulberry bark (OCBMB). The process was optimized by response surface methodology. According to the results of the signal factor test, the Box–Behnken design was employed to investigate the effects of four chosen independent variables (ultrasonic power, extraction time, ethanol concentration, and acetic acid concentration) on the oxyresveratrol extraction, and the response surface plots showed that the parameters exhibited interactive effects. The optimal conditions were as follows: extraction temperature, 50°C; ratio of solution to solid (v/m), 20:1; ultrasonic power, 496.23 W; extraction time, 113 min; ethanol concentration, 70.98%; acetic acid concentration, 0.77%. Under these optimal conditions, experimental values well matched with the predicted values, which indicated the model used had extremely good fitting degree and the response surface methodology for optimizing Ultrasonic-assisted extraction of OCBMB was successful.  相似文献   

13.
系统研究了以加勒比松树皮为原料提取原花青素的方法及工艺条件。研究对比了常规溶剂浸提、超声波提取及微波辅助提取等方法对原花青素提取得率的影响。实验结果表明,溶剂浸提采用 70% 乙醇溶液时原花青素的得率最高。在3种提取方法中,超声波提取法和微波辅助提取法提取效果较优。前者能在短时间内取得较高的提取得率,而后者需进一步延长微波辅助作用后溶剂浸提的时间才能达到较好的提取效果。超声波提取法的适宜提取条件为: 提取温度 50℃,功率 100 W,料液比1:11,提取时间 1.5 h;微波辅助提取法的适宜提取条件为: 功率 200 W,微波处理时间 30 s,料液比1:11,提取温度 50℃,提取时间 6 h。在上述条件下原花青素得率分别为 7.47% 和 7.69%。  相似文献   

14.
花生壳中黄酮的超声辅助提取工艺研究   总被引:1,自引:0,他引:1  
徐国梅  谢萌 《陕西化工》2012,(10):1707-1709
在超声波辅助下,用有机溶剂提取花生壳中的黄酮,以芦丁作为标品检测黄酮的提取率,以乙酸乙酯、乙醇、丙酮为溶剂,研究了提取时间、溶剂体积、超声频率等对提取率的影响。结果表明,超声波提取黄酮的最佳工艺条件是用60%乙酸乙酯为溶剂,提取时间为45 min,超声波频率为80 Hz,此时提取率最高为3.851%。  相似文献   

15.
BACKGROUND: Uniform design was used to optimize the ultrasonic‐assisted extraction of cordycepin from cultured Cordyceps militaris. The peak area of cordycepin identified using high performance liquid chromatography (HPLC) at a detection wavelength of 260 nm was considered the detection index. Three factors, ethanol concentration, extraction time and volume ratio of solvent to sample were studied. Optimal quadric polynomial step by step regression was applied to process the experimental results. RESULTS: Results show that the main factors affecting cordycepin extraction yield were the volume ratio of solvent to sample, extraction time and ethanol concentration, in that order. Cordycepin extraction yield reached a peak with ethanol concentration 20.21%, extraction time 101.88 min, and volume ratio of solvent to sample 33.13 mL g?1. An extraction model was developed based on the findings. CONCLUSION: A direct, reliable and accurate assay has been developed for the quantification of cordycepin in cultured Cordyceps militaris by a HPLC‐DAD method. The validation procedure confirmed that this method is appropriate for the quality control of cordycepin. Results show that the uniform experimental design approach is useful for finding polynomial functions describing the relationships between variables and responses and to find the best experimental conditions for the extraction of cordycepin in the experimental domain considered. Copyright © 2007 Society of Chemical Industry  相似文献   

16.
元宝枫绿原酸的超声提取方法研究   总被引:13,自引:1,他引:13  
刘祥义  付惠 《云南化工》2003,30(2):23-25
以乙醇溶液为溶剂 ,利用超声效应提取元宝枫叶中绿原酸 ,对超声强度 ,超声作用时间 ,料液比等因素进行研究。其较佳条件为 :室温下乙醇质量分数 3 0 % ,超声强度 2档 ,作用时间 15min ,料液比为 1∶16,提取次数2次。  相似文献   

17.
《分离科学与技术》2012,47(3):410-415
The extraction yield of fucoxanthin from Phaeodactylum tricornutum, a marine diatom, was investigated for 16 h as the functions of the kind of solvent, temperature, and solvent/diatom weight ratio. Acetone, ethanol, and ethyl acetate were used as solvents for the extractions. The extraction yield increased in a saturation manner with the extraction time when the extraction temperatures were 30°C and 40°C. However, the extraction yield increased with time in the early stage of the extraction; thereafter, it was stagnant or decreased with time in the late stage at 50°C, 75°C, and 85°C. The thermal deterioration would suppress the extraction yield in the late stage at those higher temperatures. The maximum extraction yield was obtained at 40°C and no significant benefit in the extraction yield was obtained when the extraction period was extended over 12 h. The extraction yield markedly increased when the solvent/diatom ratio increased from 3/1 to 6/1, but no marked benefit was obtained when the amount of solvent increased over the ratio of 6/1. Ethanol was the most effective solvent in the extraction of fucoxanthin, and the extraction yield was greater in the order of ethanol > acetone > ethyl acetate.  相似文献   

18.
《分离科学与技术》2012,47(5):673-681
Artemisinin is a compound extracted from Artemisia annua L. with a remarkable curative effect against malaria. It can be extracted using ultrasound-assisted extraction (UAE) and then detected via HPLC. In this study, response surface methodology (RSM) was used to optimize UAE conditions for obtaining the maximum yield of artemisinin. Three independent variables (ratio of solvent to material, extraction temperature, and ultrasonic power) were evaluated using the Box-Behnken experimental design, with the yield of artemisinin as a response variable. Experimental data were highly fitted to a mathematical-regression model using multiple linear regression (MLR). Based on response surface plots, the three independent variables exhibited interactive effects on the yield of artemisinin. The optimal extraction conditions were as follows: 42.71 mL/g ratio of solvent to material, 41.86°C extraction temperature and 120 W ultrasonic power. The predicted yield of artemisinin by model was 0.7848%, whereas the actual yield in the extracts was 0.7826% ± 0.0790% in adjusted optimal conditions, with a relative error of 0.28%. The results undoubtedly demonstrated that RSM could be used to explore the optimum conditions of artemisinin extraction.  相似文献   

19.
《分离科学与技术》2012,47(3):671-681
Abstract

Response surface methodology (RSM) was applied to predict optimum conditions for microwave‐assisted extraction (MAE) of flavonoid from Radix Astragali. A central composite design was used to monitor the effect of temperature, extraction time, solvent‐to‐material ratio, and the ethanol concentration on yield of total flavanoid (TFA). Optimum extraction conditions were predicted as 108.2°C, 26.7 min, 23.1 ml/g solvent‐to‐material ratio and 86.2% ethanol. The maximum yield 1.234±0.031 mg/g was close to the yield of Soxhlet and higher than that of ultrasound assisted extraction and heat reflux extraction. MAE was an effective alternative to conventional extraction methods.  相似文献   

20.
采用单因素和正交试验对野生八角莲中黄酮类化合物的提取工艺进行研究。主要考察乙醇浓度、料液比、超声时间及超波功率等4个因素对提取率的影响,结果表明:超声波辅助提取的最佳工艺条件为:乙醇浓度50%、料液比1∶20、超声时间25 min、超声功率120 W,黄酮类化合物的提取率为7.183%。  相似文献   

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