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Optimized Ultrasound-assisted Extraction of Proacyanidins from Purple Cabbage 被引量:2
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作者 栾娜 刘行 《Agricultural Science & Technology》 CAS 2013年第3期512-515,519,共5页
[Objective] The paper was to optimize ultrasound-assisted extraction of proacyanidins from purple cabbage. [Method] The ultrasound-assisted extraction technology was used to study the extraction of proacyanidins from ... [Objective] The paper was to optimize ultrasound-assisted extraction of proacyanidins from purple cabbage. [Method] The ultrasound-assisted extraction technology was used to study the extraction of proacyanidins from purple cabbage. The effect of ethanol concentration, temperature, time, material-solution ratio and the power of ultrasound on extracting efficiency were studied by single-factor experiment. Based on this, L16(4%orthogonal test were conducted to determine the optimal condi- tion for extraction of proacyanidins from purple cabbage. [Result] The optimal condi- tion for extraction of proacyanidins from purple cabbage was as follows: ethanol concentration 50%, extraction temperature 50℃, extraction time 1 h, extraction power 540 W, material-liquid ratio 1:20. The extraction rate of procyanidins under this condition reached 104.8 mg/g. [Conclusion] The study provided a theoretical basis for scientific and reasonable utilization of procyanidins in purple cabbage. 展开更多
关键词 Purple cabbage Proacyanidins ultrasound extraction
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Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds 被引量:2
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作者 JING Li-jia LI Si-yang CHANG Zui WANG Yang YAN Xiu-feng 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期239-242,共4页
Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present... Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present study,ultrasound-assisted extractions(UAE) of CPT from C.acuminata seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid Chromatography.The conditions of alkaline species and concentrations,extraction time,extraction temperature and ultrasonic power were optimized.Results show that both Na3PO4 and Na2CO3 solutions gain good extraction yields,whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does,thus aqueous Na2CO3 is more beneficial for the extraction.The optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50°C and ultrasonic power of 400 W for 60 min.Comparing with UAE with ethanol,the extraction with 0.5% Na2CO3 solution achieves higher yield.Moreover,aqueous Na2CO3 as a solvent has various advantages including non-toxicity,inflammable,non-corrosive and low cost,which ensure this UAE method is a superior method with high utilizing prospect. 展开更多
关键词 CAMPTOTHECIN Camptotheca acuminata ultrasound-assistant extraction
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Optimization of Ethanol-Ultrasound-Assisted Destabilization of a Cream Recovered from Enzymatic Extraction of Soybean Oil 被引量:1
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作者 Li Yang Sui Xiaonan +5 位作者 Qi Baokun Zhang Yan Feng Hongxia Zhang Yana Jiang Lianzhou Wang Tong 《大豆科技》 2019年第S01期24-34,共11页
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 oi... 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 R2=0.9591.Optimized variables were:ethanol concentration of73%,ethanol addition volume of 0.55 L/kg,ultrasound power of 427 W,ultrasound time of 47 s,and ultrasound temperature of 53℃.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 ethanoltreated cream,and the SEM images clearly showed that the ultrasound treatment affected dispersing and fracturing of the microstructure of ethanol-treated cream. 展开更多
关键词 ETHANOL ultrasound Enzyme-assisted aqueous extraction processing CREAM Soybean oil
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Pectinmethylesterase extraction from orange solid wastes: Optimization and comparison between conventional and ultrasound-assisted treatments
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作者 Antonio D. Rodriguez-Lopez Luis Mayor +2 位作者 María M. Galfarsoro Jorge Martinez-Otalo Esperanza M. Garcia-Castello 《Agricultural Sciences》 2013年第9期45-50,共6页
During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is thei... During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is their treatment by addition of lime and a latter pressing, obtaining a press cake and a press liquor rich in sugars (10&#176;Brix) and citric acid, protein, pectin and ethanol. For non-thermal concentration of press liquor to obtain citruss molasses (65&#176;-70&#176;Brix), the removal of pectin is necessary. Traditionally, depectinization of juices has been done by using pectinmethylesterase (PME) enzymes from external sources. In this work it performed the extraction of PME enzymes from orange peels to obtain the optimum extraction conditions. Two different methods of solventextraction were compared (conventional andultrasound-assisted methods). For the conventional extraction experiments, a central composite design with three variables ([NaCl], pH and time) and five replicates of the center point was used. For ultrasound-assisted extraction, experiments were done at pH = 5.5 and [NaCl] = 1.25M), varying extraction time (1-30 min). Response variables were PME activity, protein content and a ratio between them, named PME effectiveness (ηPME). At the same experimental conditions (pH =5.5, [NaCl] = 1.25 M, t = 15 min) it was found that conventional extractions led to slightly better results in terms of ηPME than ultrasound-assisted extraction method. 展开更多
关键词 ORANGE Peel SOLID-LIQUID extraction ultrasound-assisted extraction PECTINMETHYLESTERASE Press Liquor
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Effect of Ultrasound-Assisted Extraction of Phenolic Compounds on the Characteristics of Walnut Shells
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作者 Hannah Han Shusheng Wang +3 位作者 Milan Rakita Yanting Wang Qingyou Han Qin Xu 《Food and Nutrition Sciences》 2018年第8期1034-1045,共12页
Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially ... Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially good natural sources of antioxidants for the food and pharmaceutical industries. In this study, phenolic compounds were extracted using an ultrasonic bath, an ultrasonic probe and a standard shaking method. The extraction yield achieved with an ultrasonic probe was 51.2 mg GAE/g DW, two times higher than both the shaking method and the ultrasonic bath method which were 20.6 mg GAE/g DW and 25.8 mg GAE/g DW, respectively. Phenolic extraction was further improved by a size reduction of the walnut shells. The best extraction yield of 52.8 mg GAE/g DW was attained when the particle size was between 45 - 100 mesh. The ultrasonic probe treatment is the best method for extraction of phenolic compounds from walnut shells. Scanning electron microscopy (SEM) imaging indicated that the ultrasonic probe treatment could better rupture the hard structure of the cells, increasing the penetration of solvents and thus the extraction yield. 展开更多
关键词 WALNUT SHELL ultrasound-assisted extraction TOTAL PHENOLIC Content (TPC) Particle Size SEM Analysis
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Optimization of Ultrasonic-assisted Extraction of Polysaccharide from Hibiscus syriacus L.
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作者 Haibo DENG Bei NING +3 位作者 Shunfan ZHU Chenzhong JIN Yihong HU Xuejiao ZHANG 《Agricultural Biotechnology》 CAS 2018年第3期161-164,共4页
The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extract... The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extraction times,and material-to-liquid ratio were considered as independent variables. The results suggested that the best extraction condition were determined as the extraction temperature at 80 ℃,the ultrasonic treatment time of 40 min,the material-to-liquid ratio at1∶ 20( g/ml),and the extraction times of 3. Under the optimal conditions,the extraction rate of polysaccharides from Hibiscus syriacus was 3. 114%. 展开更多
关键词 Hibiscus syriacus L. POLYSACCHARIDE ultrasound-assisted extraction
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Enzyme extraction by ultrasound from sludge flocs 被引量:8
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作者 YU Guanghui,HE Pinjing,SHAO Liming,ZHU Yishu State Key Laboratory of Pollution Control and Resource Reuse,Key Laboratory of Yangtze River Water Environment,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第2期204-210,共7页
Enzymes play essential roles in the biological processes of sludge treatment. In this article, the ultrasound method to extract enzymes from sludge flocs was presented. Results showed that using ultrasound method at 2... Enzymes play essential roles in the biological processes of sludge treatment. In this article, the ultrasound method to extract enzymes from sludge flocs was presented. Results showed that using ultrasound method at 20 kHz could extract more types of enzymes than that at 40 kHz and ethylenediamine tetraacetic acid (EDTA) methods. The optimum parameters of ultrasound extraction at 20 kHz were duration of 10 min and intensity of 552 W/g TSS. Under the optimum condition, ultrasound could break the cells and extract both the extracellular and a small part of intercellular enzymes. Ultrasound intensity was apparently more susceptive to enzyme extraction than duration, suggesting that the control of intensity during ultrasound extraction was more important than that of duration. The Pearson correlation analysis between enzyme activities and cation contents revealed that the different types of enzymes had distinct cation binding characteristics. 展开更多
关键词 ENZYMES extracellular polymeric substances extraction method sludge flocs statistical analysis ultrasound
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Enhanced extraction of essential oil from Cinnamomum cassia bark by ultrasound assisted hydrodistillation 被引量:6
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作者 Guanghui Chen Fengrui Sun +3 位作者 Shougui Wang Weiwen Wang Jipeng Dong Fei Gao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期38-46,共9页
Cinnamon essential oil with many bioactivities is an important raw material for the production of various chemicals,and the conventional hydrodistillation(HD)for cinnamon oil extraction always require a longer extract... Cinnamon essential oil with many bioactivities is an important raw material for the production of various chemicals,and the conventional hydrodistillation(HD)for cinnamon oil extraction always require a longer extraction time.In this work,ultrasound-assisted hydrodistillation extraction(UAHDE)technique was employed to enhance the extraction efficiency of essential oils from cinnamon barks.The parameters with significant effects on the essential oil extraction efficiency(ultrasound time,ultrasound power,extraction time,liquid–solid ratio)were optimized,and the proposed UAHDE was compared with the conventional HD extraction in terms of the extraction time,extraction yield,and physicochemical properties of extracted oils.Compared to the HD extraction,the UAHDE resulted in a shorter extraction time and a higher extraction yield.Using GC–MS analysis,the UAHDE provided more valuable essential oil with a high content of the vital trans-cinnamaldehyde compounds compared with the HD.Scanning electron micrograph(SEM)confirmed the efficiency of ultrasound irradiation for cinnamon oil extraction.In addition,the analysis of electric consumption and CO_(2) emission shows that the UAHDE process is a more economic and environment-friendly approach.Thus,UAHDE is an efficient and green technology for the cinnamon essential oil extraction,which could improve the quantity and quality of cinnamon oils. 展开更多
关键词 Cinnamon oil extraction ultrasound DISTILLATION Optimization Chemical composition
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Determination of Five (5) Possible Contaminants in Recycled Cardboard Packages and Food Simulants Using Ultrasound Assisted Extraction Coupled to GC-MS 被引量:3
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作者 Ioanna-Efpraxia Parigoridi Konstantoula Akrida-Demertzi Panagiotis G. Demertzis 《Materials Sciences and Applications》 2014年第10期745-751,共7页
A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphen... A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphenyl and o-terphenyl}] that can be found as residues in recycled cardboards intended for use as food packaging materials and to test for migration levels of these compounds in a food simulant (Tenax). A main objective was to develop a modified rapid and reliable method for the identification and quantification of these compounds at low concentrations. The method was based on ultrasound-assisted solvent extraction (UAE) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The developed method was applied to analyze 3 commercially available recycled carton board food-packaging materials and also to study the potential migration of the 5 organic pollutants from these materials into Tenax to check if these recycled cardboards can be considered as suitable for use in direct contact with foodstuffs. The limits of detection (LODs) of standard solutions of the 5 compounds were determined at a signal-to-noise ratio of 3. The LODs and the limits of quantification (LOQs) of examined pollutants ranged between 0.005 to 0.5 mg/kg, and 0.1 to 1 mg/kg, respectively. The extremely low amounts of most contaminants that migrate from packaging materials to Tenax indicate that the recycled cardboards tested can be safely used for direct food contact applications. 展开更多
关键词 Gas Chromatography-Mass SPECTROMETRY ultrasound-assisted SOLVENT extraction Organic POLLUTANTS Recycled CARDBOARD
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Optimization of Extraction Technology of Ellagic Acid from Pomegranate Peels with Orthogonal Experiment 被引量:4
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作者 干霞 陈亚楠 +3 位作者 余亮 朱柯成 曾星月 白琦 《Agricultural Science & Technology》 CAS 2012年第11期2404-2408,共5页
[Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to ... [Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to extract the ellagic acid from pomegranate peels, and the concentration of ellagic acid was measured by using ul- traviolet spectrophotometry; L9(34) orthogonal experiment was designed with four fac- tors at three levels, to investigate the effect of extraction temperature, extraction du- ration, solid-liquid ratio and ultrasound power on extraction rate of ellagic acid. [Re- sult] The optimal extraction condition for ellagic acid is extraction temperature of 30 ~C, solid-liquid ratio of 1:200, extraction duration of 20 min, and ultrasound power of 50 W. The relationship between primary and secondary factors affecting experimental indicators was solid-liquid ratio 〉 extraction duration 〉 ultrasound power 〉 extraction temperature. [Conclusion] Solid-liquid ratio has the maximum effect on extraction rate of ellagic acid. The ellagic acid extraction technology identified in this study is rea- sonable and feasible. 展开更多
关键词 Pomegranate peels ultrasound Ellagic acid extraction technology Or-thogonal experiment
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Ultrasonically Assisted Extraction of Isoflavones from Stem of Pueraria lobata (Willd.) Ohwi and Its Mathematical Model 被引量:15
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作者 徐化能 张颖心 何潮洪 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期861-867,共7页
Ultrasonically assisted extraction of isoflavones from the stem of Pueraria lobata (Willd.) Ohwi has been carried out with an ultrasonic extracting apparatus (20kHz, electrical power input to the transducer in 0-6... Ultrasonically assisted extraction of isoflavones from the stem of Pueraria lobata (Willd.) Ohwi has been carried out with an ultrasonic extracting apparatus (20kHz, electrical power input to the transducer in 0-650W). The influence of the electrical power input and extraction time on the'extraction yield is investigated in water, n-butanol, and 95% (by volume) and 50% (by volume) ethanol aqueous solution. The experimental results indicate that the yields of total isoflavones are higher in ultrasonically assisted extraction than those obtained from con-ventional extraction.Moreover,a mathematical model is proposed,by introducing the electrical power input to index the ultrsound intensity,to describe the behavior of ultrasonically assisted extraction.It is found that the model calcuations are in good agreement with the experimental data. 展开更多
关键词 ultrasound mathematical model extraction Pueraria lobata (Willd.) Ohwi
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Optimal Method of Extraction Process of Flavonoids from Ginkgo biloba
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作者 Qun CHEN Lang TANG Shitang MA 《Asian Agricultural Research》 2019年第7期66-70,共5页
[Objectives] To optimize the extraction of total flavone in folium Ginkgo biloba leaves.[Methods] Using the ultrasonic extraction method, the three levels of maximum impact were selected by each factor selection, and ... [Objectives] To optimize the extraction of total flavone in folium Ginkgo biloba leaves.[Methods] Using the ultrasonic extraction method, the three levels of maximum impact were selected by each factor selection, and the optimal extraction technology was obtained by box-benhnken test design analysis.[Results] After analyzing the results, the optimal process was as follows: a time of 28.89 min and liquid/material ratio of 31.38∶ 1, the temperature was 40.74℃. In this way, NaNO 2-Al (NO 3) 3-NaOH was used as color developing agent, and the theoretical extraction of flavone in ginkgo leaf can reach 11.74 mg/g.[Conclusions] This method can be used to extract total flavonoids from G. biloba leaves with simple operation, low cost and good repeatability. 展开更多
关键词 GINKGO LEAF ultrasound extraction TOTAL FLAVONE Single factor Response method
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Extraction of Carotenoids and Fatty Acids from Microalgae Using Supercritical Technology 被引量:1
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作者 Lourdes Casas Cardoso Casimiro Mantell Serrano +2 位作者 Miguel Rodríguez Rodríguez Enrique J. Martínez de la Ossa Luis M. Lubián 《American Journal of Analytical Chemistry》 2012年第12期877-883,共7页
The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-as... The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-assisted extraction using N, N-dimethylformamide (DMF). The effects of extraction conditions on supercritical CO2 extraction with and within cosolvent were analyzed at different temperatures (40℃, 50℃ and 60℃) and pressures (200, 300 and 400 bars). SFE with CO2 proved to be the most selective method for the extraction of β-carotene, but under these conditions the contents of zeaxanthin and fatty acids were only comparable to or lower than those obtained with techniques that use SFE cosolvent. The SFE technique with CO2 and ethanol simultaneously extracted β-carotene and zeaxanthin and not only increased the concentrations of fatty acids obtained, but also helped to remove fatty acids (palmitoleic and linolenic acid) that were not obtained with pure CO2. Comparison of the supercritical technology with the ultrasound-assisted extraction (UAE) shows that the former technique is the most appropriate due to the fact that ethanol is generally regarded as a safe solvent in comparison to DMF. 展开更多
关键词 Carotenoids FATTY ACIDS SYNECHOCOCCUS sp. SUPERCRITICAL Technology ultrasound-assisted extraction
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Extraction of Effective Ingredient from Pomegranate Peels and Its Whitening Effect
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作者 Xinyu AO Shouqing LIU Yuhui CHEN 《Agricultural Biotechnology》 CAS 2012年第1期19-22,共4页
[ Objective] This study aimed to extract the effective ingredient of pomegranate peels and explore its whitening effect. [ Method] Pomegranate peels were used as materials for single factor experiment to determine the... [ Objective] This study aimed to extract the effective ingredient of pomegranate peels and explore its whitening effect. [ Method] Pomegranate peels were used as materials for single factor experiment to determine the optimal technique for effective ingredient extraction from pomegranate peels and explore the inhibition of the extracts on tyrosinase and whitening effect of the effective ingredient of pomegranate peels. [ Result] The optimal conditions for ultrasound-assisted extraction of effective ingredient in pomegranate peels were: liquid-to-solid ratio of 1:20 with 60% ethanol, extraction temperature of 60℃, ultrasonic intensity of 7 and pro- cessing time of 40 min, which led to relatively strong inhibition effect of pomegranate peel extracts on tyrosinase. The inhibition rate of extracts obtained with com- mon solvent reflux extraction method was only around 60%, while the inhibition rate of extracts obtained with ultrasound-assisted extraction method on tyrosinase ac- tivity had achieved around 90%, showing a very significant the difference, which indicated that during the process of extraction of effective ingredient from pome- granate peels, appropriate ultrasound-assistance was advantageous to the extraction of active ingredients; in addition, the inhibition effect of extracts on tyrosinase had increased with the increasing concentration of extracts, and the inhibition rate could achieve 100%. [ Condusion] This study provided a certain theoretical ba- sis for the utilization of pomegranate peels as natural green materials to develop whitening cosmetics. 展开更多
关键词 ultrasound-assisted extraction Common solvent reflux extraction Pomegranate peels TYROSINASE
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Ultrasound-assisted Low Density Solvent Based Dispersive Liquid-liquid Microextraction for Determination of Phthalate Esters in Bottled Water Samples 被引量:5
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作者 UANSIRI Sutthirak VICHAPONG Jitlada KANCHANAMAYOON Wanna 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2016年第2期178-183,共6页
A technique of ultrasound-assisted low density solvent based dispersive liquid-liquid microextraction was developed for the determination of four phthalate esters, including dimethyl phthalate(DMP), diethyl phthalat... A technique of ultrasound-assisted low density solvent based dispersive liquid-liquid microextraction was developed for the determination of four phthalate esters, including dimethyl phthalate(DMP), diethyl phthalate(DEP), di-n-butyl phthalate(DnBP) and di(2-ethylhexyl) phthalate(DEHP) in bottled water samples. A low density solvent, toluene, was selected as extraction solvent. In the extraction process, a mixture of 15 μL of toluene(extraction solvent) and 100 μL of methanol(disperser solvent) was rapidly injected into 1.0 mL of water samples. A cloudy solution was formed after ultrasounded for 5 min, and then centrifuged at 5000 r/min for 5 min. The enriched analytes in the floa- ting phase were determined by means of gas chromatograph. Under the optimum conditions, the enrichment factors were found to be in a range of 29--67, and the recoveries were ranged from 81.2% to 103.9%. The limits of the detection were in a range of 3.8--5.6 μg/L. The proposed method was applied to the extraction and determination of phthalate esters in bottled water samples, and the concentrations of phthalate esters found in the water samples were below the allowable levels. 展开更多
关键词 Phthalate ester Sample extraction Gas chromatography Drinking water ultrasound-assisted method
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Evaluation of Oil Yield of Oil Shale by Infrared Spectrometry Coupled with Ultrasound-assisted Extraction 被引量:1
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作者 ZHAO Zhenying LIN Jun +2 位作者 YU Yong HOU Chuanbin SUN Yuyang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2015年第3期352-356,共5页
The oil yield of oil shale was evaluated by Fourier transform infrared(FTIR) spectrometry coupled with ultrasound-assisted extraction. The extraction conditions, including the amount of sample, extraction time and e... The oil yield of oil shale was evaluated by Fourier transform infrared(FTIR) spectrometry coupled with ultrasound-assisted extraction. The extraction conditions, including the amount of sample, extraction time and extrac- tion temperature, were examined and optimized. Twenty-four oil shale samples were collected and divided into calibration set and prediction set randomly with a ratio of 2:1. The oil yields of all the samples were determined by the routine method(low-temperature retorting) for reference. The linear regression(LR) equations of oil yield vs. the total area of the spectrum peaks in a wavenumber range of 3100--2800 cm-1 as well as the sum of absorbance of three absorption peaks(2855, 2927 and 2955 cm-l), and the multiple linear regression(MLR) model of oil yield vs. the absorbances of the three absorption peaks were constructed with the samples in calibration set and applied to the evaluation of the oil yields of the samples in prediction set, respectively. The results show that the MLR model provides more accurate predictions than the other LR two equations. The determination coefficient(P2p ), the root- mean-square error of prediction(RMSEP) and the residual prediction deviation(RPD) of the MLR model are 0.9616, 0.6458 and 3.6, respectively. The present method is a rapid and effective alternative to the routine low-temperature retorting method. 展开更多
关键词 Oil shale Oil yield ultrasound-assisted extraction Infrared spectroscopy Multiple linear regression
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Ultrasound-assisted Extraction of Kamebakaurin from Rabdosia excisa by Response Surface Methodology
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作者 TANG Jian MA Rui-li +4 位作者 LI Qian-qian JIANG Chun-bao CHEN Rui OUYANG Zhen CHEN Hai-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第6期1072-1077,共6页
For the efficient extraction of kamebakaurin(KA), the ultrasound-assisted extraction(UAE) of KA from Rabdosia excisa(R, excisa) via response surface methodology(RSM) was investigated with high-performance liqu... For the efficient extraction of kamebakaurin(KA), the ultrasound-assisted extraction(UAE) of KA from Rabdosia excisa(R, excisa) via response surface methodology(RSM) was investigated with high-performance liquid chromatography(HPLC). Effects of the experimental parameters such as extraction solvent, ratio of liquid to plant material, extraction time and extraction temperature on the extracting efficiency of KA from R. excisa were evaluated, and the purity of KA in residual was calculated. The optimized conditions were 65.5%(volume fraction) acetone, 35 ℃, time of 24.6 min with ultrasound of 80 W/L, 40 kHz, ratio of liquid to plant material at 30:1(mL/g). The maximum yield of KA is 0.708 mg/kg, with mean purity of 6.09%, indicating that ultrasound-assisted extraction is a feasible and useful method for extracting KA from R. excisa. 展开更多
关键词 ultrasound-assisted extraction Kamebakaurin Rabdosia excisa Response surface methodology
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Multi-Level Fusion in Ultrasound for Cancer Detection Based on Uniform LBP Features 被引量:1
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作者 Diyar Qader Zeebaree Adnan Mohsin Abdulazeez +2 位作者 Dilovan Asaad Zebari Habibollah Haron Haza Nuzly Abdull Hamed 《Computers, Materials & Continua》 SCIE EI 2021年第3期3363-3382,共20页
Collective improvement in the acceptable or desirable accuracy level of breast cancer image-related pattern recognition using various schemes remains challenging.Despite the combination of multiple schemes to achieve ... Collective improvement in the acceptable or desirable accuracy level of breast cancer image-related pattern recognition using various schemes remains challenging.Despite the combination of multiple schemes to achieve superior ultrasound image pattern recognition by reducing the speckle noise,an enhanced technique is not achieved.The purpose of this study is to introduce a features-based fusion scheme based on enhancement uniform-Local Binary Pattern(LBP)and filtered noise reduction.To surmount the above limitations and achieve the aim of the study,a new descriptor that enhances the LBP features based on the new threshold has been proposed.This paper proposes a multi-level fusion scheme for the auto-classification of the static ultrasound images of breast cancer,which was attained in two stages.First,several images were generated from a single image using the pre-processing method.Themedian andWiener filterswere utilized to lessen the speckle noise and enhance the ultrasound image texture.This strategy allowed the extraction of a powerful feature by reducing the overlap between the benign and malignant image classes.Second,the fusion mechanism allowed the production of diverse features from different filtered images.The feasibility of using the LBP-based texture feature to categorize the ultrasound images was demonstrated.The effectiveness of the proposed scheme is tested on 250 ultrasound images comprising 100 and 150 benign and malignant images,respectively.The proposed method achieved very high accuracy(98%),sensitivity(98%),and specificity(99%).As a result,the fusion process that can help achieve a powerful decision based on different features produced from different filtered images improved the results of the new descriptor of LBP features in terms of accuracy,sensitivity,and specificity. 展开更多
关键词 Breast cancer ultrasound image local binary pattern feature extraction noise reduction filters FUSION
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油茶蒲黄酮的制备及组分鉴定 被引量:1
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作者 吴苏喜 李扬 +3 位作者 韩小苗 董熠辉 李万元 彭邵锋 《中国油脂》 CAS CSCD 北大核心 2024年第7期130-135,共6页
为促进油茶蒲的高值化开发利用,推动油茶产业高质量发展,以油茶蒲为原料,采用超声辅助醇提法制备油茶蒲粗黄酮,并采用AB-8大孔树脂吸附法纯化。另外,对纯化的油茶蒲黄酮的结构进行了紫外光谱和红外光谱表征,利用UPLC-Q-TOF-MS对其组分... 为促进油茶蒲的高值化开发利用,推动油茶产业高质量发展,以油茶蒲为原料,采用超声辅助醇提法制备油茶蒲粗黄酮,并采用AB-8大孔树脂吸附法纯化。另外,对纯化的油茶蒲黄酮的结构进行了紫外光谱和红外光谱表征,利用UPLC-Q-TOF-MS对其组分进行了鉴定。结果表明:采用超声辅助醇提法制备的油茶蒲粗黄酮中黄酮含量为32.41%,采用AB-8大孔树脂纯化后的黄酮含量为70.14%,黄酮总回收率为60.12%;紫外光谱与红外光谱分析表明,纯化物具有明显的黄酮类紫外、红外特征光谱,证明该纯化物主要成分为黄酮类化合物;UPLC-Q-TOF-MS从该纯化物中共鉴定出44种多酚类和黄酮类化合物,其中14种黄酮类化合物、30种多酚类化合物,油茶蒲黄酮多以黄酮苷类化合物形式存在,且多为山奈酚的糖苷类化合物,油茶蒲黄酮中含有原花青素、儿茶素、表儿茶素及没食子酸等抗氧化活性成分。根据油茶蒲黄酮的组成成分,推测其具有开发成为抗糖尿病食品以及与抗癌药物联用治疗疾病的潜力。 展开更多
关键词 油茶蒲 黄酮类化合物 多酚类化合物 组分鉴定 超声辅助醇提
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正交试验法优化紫苏叶中总黄酮提取工艺及体外抗氧化活性研究 被引量:1
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作者 尹丽 孟学林 《饲料研究》 CAS 北大核心 2024年第4期99-103,共5页
试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率... 试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率影响的主次顺序为:提取温度>乙醇浓度>液料比>提取时间。紫苏叶总黄酮最优提取工艺参数为乙醇浓度50%、液料比20 mL/g、提取温度70℃和提取时间45 min。在此条件下,紫苏叶总黄酮得率为4.05%。紫苏叶总黄酮对DPPH自由基与羟自由基具有较强的清除作用,其IC50值分别为160 mg/L和196 mg/L。研究表明,紫苏叶总黄酮具有较强的抗氧化性能,是一种优质的天然抗氧化物质。 展开更多
关键词 紫苏叶 总黄酮 正交试验 抗氧化活性 超声辅助提取
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