期刊文献+
共找到44篇文章
< 1 2 3 >
每页显示 20 50 100
Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis
1
作者 Jun TANG Jianguang ZENG +1 位作者 Hao LI Chenzhong JIN 《Agricultural Biotechnology》 CAS 2023年第2期91-95,104,共6页
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex... With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%. 展开更多
关键词 Pueraria edulis Total flavonoids Condensation reflux extraction method ultrasound-assisted extraction
下载PDF
Optimization of Ultrasound-assisted Extraction Conditions for Polysaccharides from Pinus tabulaeformis Seed Shells
2
作者 蒋龙 杨国庆 +2 位作者 杨鹏 刘伟 张大伟 《Agricultural Science & Technology》 CAS 2013年第12期1826-1829,共4页
[Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted fr... [Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted from P. tabulaeformis seed shells by ultrasound-assisted hot water extraction method and detected by phenol- concentrated sulfuric acid method. The effect of extraction temperature, extraction duration, solid-liquid ratio and extraction frequency on the extraction of polysaccha- rides was investigated using single-factor gradient experiment and the extraction conditions for polysaccharides from P. tabulaeformis seed shells were optimized us- ing L9(34) orthogonal design. [Result] The content of polysaccharides extracted twice at 60 ℃ for 25 min with solid-liquid ratio of 1:3.5 reached the maximum. The re- covery rate (n=-5) ranged from 97.71% to 100.67% and RSD was 1.56%, suggesting high stability. [Conclusion] A simple and efficient method for ultrasound-assisted ex- traction of polysaccharides from P. tabulaeformis seed shells was established in this study, which laid solid foundation for the development and utilization of abandoned pine nut shell resources. 展开更多
关键词 ultrasound-assisted extraction Spectrophotography Pinus tabulaeformis seed shells Polvsaccharides
下载PDF
Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds 被引量:2
3
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
下载PDF
Ultrasound-assisted Enzymatic Extraction of SDF on Passion Fruit Seeds 被引量:1
4
作者 YANG Cui-feng TENG Zheng +2 位作者 WU Guan-ying LIAO Shi-kong HUANG Kun-lin 《Agricultural Science & Technology》 CAS 2020年第1期28-32,共5页
Ultrasound-assisted enzymatic extraction of soluble dietary fiber(SDF) from passion fruit seeds was carried out in order to shorten the extraction time and increase the yield of SDF. The effects of cellulase concentra... Ultrasound-assisted enzymatic extraction of soluble dietary fiber(SDF) from passion fruit seeds was carried out in order to shorten the extraction time and increase the yield of SDF. The effects of cellulase concentration, ultrasonic power, extraction temperature, solid-liquid ratio and water bath time on the SDF yield of passion fruit were studied by single factor analysis. And the orthogonal experiment was designed to optimize the extraction conditions. The results showed that the optimum conditions for the extraction of SDF from passion fruit by ultrasoundassisted enzymatic method were cellulase concentration 1.5%, ultrasonic power 120 W, solid-liquid ratio(g/mL) 1 ∶ 15, extraction temperature 55 ℃, and water bath time 160 min. The SDF extraction rate was determined to be 5.12%. 展开更多
关键词 Passion fruit seeds Soluble dietary fiber ultrasound-assisted Enzymatic extraction
下载PDF
Analysis of anticancer compound,indole-3-carbinol,in broccoli using a new ultrasound-assisted dispersive-filter extraction method based on poly(deep eutectic solvent)-graphene oxide nanocomposite
5
作者 Yanan Yuan Huanhuan Chen +2 位作者 Yehong Han Fengxia Qiao Hongyuan Yan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第2期301-307,共7页
Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challengin... Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature.In this study,a rapid,accurate,and lowcost ultrasound-assisted dispersive-filter extraction(UADFE)technique based on poly(deep eutectic solvent)-graphene oxide(PDES-GO)adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time.PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption.UADFE was developed by combining dispersive solid-phase extraction(DSPE)and filter solid-phase extraction(FSPE)to realize rapid extraction and separation.Based on the above two strategies,the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography(HPLC)allowed the rapid(15-16 min),accurate(84.3%-96.4%),and low-cost(adsorbent:3.00 mg)analysis of I3C in broccoli and was superior to solid-phase extraction,DSPE,and FSPE methods.The proposed method showed remarkable linearity(r=0.9998;range:0.0840-48.0 mg/g),low limit of quantification(0.0840 mg/g),and high precision(relative standard deviation<5.6%).Therefore,the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples. 展开更多
关键词 INDOLE-3-CARBINOL BROCCOLI Poly(deep eutectic solvent)-graphene oxide ultrasound-assisted dispersive-filter extraction Rapid analysis
下载PDF
Pectinmethylesterase extraction from orange solid wastes: Optimization and comparison between conventional and ultrasound-assisted treatments
6
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
下载PDF
Effect of Ultrasound-Assisted Extraction of Phenolic Compounds on the Characteristics of Walnut Shells
7
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
下载PDF
Extraction and Purification Process Optimization and Antioxidant Activity in vitro of Flavonoids in Amaranthus caudatus L. 被引量:3
8
作者 Hongliang YAO Huihui LI 《Medicinal Plant》 CAS 2020年第4期48-53,共6页
[Objectives]To explore the optimal extraction and purification process of the flavonoids in Amaranthus caudatus L.and to study the antioxidant activity in vitro of the flavonoids in A.caudatus.[Methods]Taking A.caudat... [Objectives]To explore the optimal extraction and purification process of the flavonoids in Amaranthus caudatus L.and to study the antioxidant activity in vitro of the flavonoids in A.caudatus.[Methods]Taking A.caudatus as the raw material,flavonoids were extracted by alcohol extraction method,and AB-8 macroporous adsorption resin was selected for purification.The hydroxyl radical scavenging ability,DPPH radical scavenging ability,and O^2-radical scavenging ability were used as evaluation indicators,to explore the antioxidant activity in vitro of the flavonoids in A.caudatus.[Results]The optimal extraction process conditions of flavonoids in A.caudatus are:liquid-to-material ratio 40:1,extraction temperature 60℃,ethanol concentration 60%,ultrasonic power 320 W,extraction time 50 min.Under these conditions,the extraction yield of flavonoids in A.caudatus is(1.35±0.01)%.The optimal purification process conditions of flavonoids in A.caudatus are 2.5 g AB-8 macroporous adsorption resin,sample volume 5 mL,mass concentration of adsorption solution 1.60 mg/mL,pH value of adsorption solution 3.0,sample flow rate 3 BV/h,ethanol concentration in desorption process is 70%and the desorption flow rate is 3 BV/h.Under these conditions,the recovery rate reaches 88.35%±0.68%.[Conclusions]A.caudatus has a high content of flavonoids and has excellent free radical scavenging ability in vitro.This study is intended to provide important technical support for the research of flavonoid activity of A.caudatus and the development of functional products. 展开更多
关键词 Amaranthus caudatus L. FLAVONOIDS ultrasound-assisted extraction PURIFICATION Antioxidant activity
下载PDF
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
9
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
下载PDF
Extraction of Carotenoids and Fatty Acids from Microalgae Using Supercritical Technology 被引量:1
10
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
下载PDF
Optimizing the Extraction of Anthocyanins from Pitaya(Hylocereus undatus)Pericarp 被引量:1
11
作者 Shuiming CHENG Xia ZENG +1 位作者 Guoyu ZHOU Caimei YAN 《Agricultural Biotechnology》 CAS 2020年第4期168-173,共6页
[Objectives]This study was conducted to confirm the existence of anthocyanins in pitaya(Hylocereus undatus)pericarp and optimize the extraction condition.[Methods]Single-factor tests were carried out on five factors:e... [Objectives]This study was conducted to confirm the existence of anthocyanins in pitaya(Hylocereus undatus)pericarp and optimize the extraction condition.[Methods]Single-factor tests were carried out on five factors:ethanol concentration,extraction temperature,ultrasonic power,solid-to-liquid ratio and extraction time.Based on the single-factor test results,four factors and three levels of process conditions were optimized by Box-Behnken design test.[Results]Anthocyanins exist in the pericarp of pitaya,and the optimum conditions were extraction temperature 49℃,ultrasonic power 120 W,extracted time 2 h and ethanol concentration 60%.Under these conditions,the average yield of anthocyanins was 80 mg/100g.[Conclusions]This study provides a theoretical basis for the extraction of anthocyanins from the pericarp of red-flesh pitaya. 展开更多
关键词 Hylocereus undatus pericarp ANTHOCYANIN ultrasound-assisted extraction Response surface design
下载PDF
Extraction of Effective Ingredient from Pomegranate Peels and Its Whitening Effect
12
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
下载PDF
Optimization of Ultrasonic-assisted Extraction of Polysaccharide from Hibiscus syriacus L.
13
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
下载PDF
Determination of contents of eight alkaloids in fruits of Macleaya cordata (Willd) R. Br. from different habitats and antioxidant activities of extracts 被引量:9
14
作者 钟明 黄可龙 +2 位作者 曾建国 黎霜 张丽 《Journal of Central South University》 SCIE EI CAS 2010年第3期472-479,共8页
A reliable ultrasound-assisted extraction (UAE) method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata (Willd) R. Br. was developed. The optimization conditions of ... A reliable ultrasound-assisted extraction (UAE) method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata (Willd) R. Br. was developed. The optimization conditions of UAE were obtained by using Box-Behnken design of response surface methodology. Chromatography was carried out using a Kromasil C18 column by gradient elution with 0.1% phosphoric acid aqueous solution for HPLC-UV. All calibration curves showed good linear correlation coefficients (R^2〉0.999 6) and recoveries (from 97.3% to 104.9%) were acceptable. 1,1-diphenyl-2-picrylhydrazyl (DPPH) method was employed to test the antioxidant activity of the extract from the samples. The proposed method was successfully applied to quantifying eight components in nine samples of M.cordata, and significant variations of alkaloid contents and antioxidant aetivity of the samples from different habitats were demonstrated. It presents a powerful proof for the selection of the best sources to extract eight kinds of alkaloids. 展开更多
关键词 Macleaya cordata (Willd) R. Br. ALKALOID ultrasound-assisted extraction antioxidant activity HPLC-UV response surface methodology
下载PDF
Ultrasound-assisted Low Density Solvent Based Dispersive Liquid-liquid Microextraction for Determination of Phthalate Esters in Bottled Water Samples 被引量:5
15
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
原文传递
Ultrasound-assisted extraction of bound phenolic compounds from the residue of Apocynum venetum tea and their antioxidant activities 被引量:2
16
作者 Shengwei Sun Yiwen Zhao +10 位作者 Luyao Wang Yuzhi Tan Yaning Shi Rita-Cindy Aye-Ayire Sedjoah Yuting Shao Longxiang Li Mengxi Wang Jiashuai Wan Xia Fan Rong Guo Zhihong Xin 《Food Bioscience》 SCIE 2022年第3期502-511,共10页
Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free ... Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea. 展开更多
关键词 Apocynum venetum.L tea residue ultrasound-assisted extraction Bound phenolic compounds Structural characterization Antioxidant activity
原文传递
Evaluation of Oil Yield of Oil Shale by Infrared Spectrometry Coupled with Ultrasound-assisted Extraction 被引量:1
17
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
原文传递
Ultrasound-assisted intensified aqueous extraction of phenolics from waste Syzygium cumini leaves:Kinetic studies and evaluation of antioxidant,antidiabetic and anticancer potential 被引量:1
18
作者 Komal V.Mahindrakar Virendra K.Rathod 《Food Bioscience》 SCIE 2022年第2期594-604,共11页
This is the first report illustrating the extraction of total phenolic compounds(TPC)using the ultrasound-assisted aqueous extraction(USAE)technique from waste Syzygium cumini leaves(WSCL).A kinetic study indicated th... This is the first report illustrating the extraction of total phenolic compounds(TPC)using the ultrasound-assisted aqueous extraction(USAE)technique from waste Syzygium cumini leaves(WSCL).A kinetic study indicated that Peleg’s model was appropriately fitted to the experimental data when the effect of different parameters was checked on extraction with respect to time.Extraction yields of total phenolic contents(TPC)and total flavonoid contents(TFC)were 78.38 mg GAE/g,and 10.15 mg CE/g,respectively,at optimized parameters of 1:25 WSCL:water,35℃ temperature,134 W power,50%duty cycle and in 9 min of sonication time.Cumulative yields of TPC and TFC obtained by 5 sequential stirred batch extraction were 79.36 mg GAE/g and 10 mg CE/g,respectively.The cost and energy requirement of the USAE process was around 3000 times less than that of the Soxhlet technique.SEM images showed the changes in the morphology of the WSCL surface area before and after ultrasonic extraction.FTIR analysis showed the presence of O-H,N-H,C-H,C=C,and halogenated functional groups.The obtained WSCL extract showed antioxidant potential with an IC_(50) value of 15.64μg/mL.IC_(50) values of extract forα-amylase andα-glucosidase inhibitions were 8.3 and 6.64μg/mL.Antiproliferation activity against breast,cervical,and lung cancer showed the potential with GI50 values 252.8,112.5,and 97.8μg/mL,respectively.Aqueous extract of Syzygium cumini leaves can be used to treat oxidative stress,diabetes,and cancer. 展开更多
关键词 Syzygium cumini leaves ultrasound-assisted extraction Antioxidant phenolic compounds Anticancer activity Antidiabetic activity
原文传递
Preparation of ferric oxide-aluminium oxide carbon nanofiber nanocomposites for ultrasound-assisted dispersive magnetic solid phase extraction of 17-beta estradiol in wastewater 被引量:3
19
作者 Malesela William Lekota Anele Mpupa +1 位作者 K.Mogolodi Dimpe Philiswa N.Nomngongo 《Emerging Contaminants》 2020年第1期162-171,共10页
In this work,Fe3O4-Al2O3@CNFs nanocomposite was synthesised and used as a nanosorbent in the ultrasound-assisted dispersive magnetic solid phase extraction(UA-DMSPE)of 17-beta estradiol(E2)in wastewater samples.The qu... In this work,Fe3O4-Al2O3@CNFs nanocomposite was synthesised and used as a nanosorbent in the ultrasound-assisted dispersive magnetic solid phase extraction(UA-DMSPE)of 17-beta estradiol(E2)in wastewater samples.The quantification of E2 was achieved using high performance liquid chromatography coupled with diode array detector(HPLC-DAD).Various parameters affecting the efficiency of this sample preparation technique were optimised to achieve excellent sensitivity and high recoveries of E2.Response surface methodology was utilised for optimisation of these parameters.Using the optimised conditions,the linear dynamic range was achieved in the range of 0.1e1000 mgL^-1and the correlation coefficient was found to be 0.9981.The preconcentration factor,enrichment factor,limit of detection(LOD)and limit of quantification(LOQ)were 67,169,0.025 mgL^-1and 0.083 mg L1,respectively.The relative standard deviation(%RSD)for the intraday(n?10)and interday(n?5 working days)were 1.8%and 3.3%,respectively.The developed UA-DMSPE/HPLC-DAD method was applied for the preconcentration and determination of E2 in wastewater samples.The obtained results indicated that E2 was present in the wastewater samples. 展开更多
关键词 Carbon nanofibers ultrasound-assisted dispersive magnetic solid phase extraction 17 beta-estradiol Response surface methodology Desirability function
原文传递
Ultrasound-assisted Extraction of Kamebakaurin from Rabdosia excisa by Response Surface Methodology
20
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
原文传递
上一页 1 2 3 下一页 到第
使用帮助 返回顶部