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Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement
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作者 Chunyan Ji 《Journal of Clinical and Nursing Research》 2024年第2期196-200,共5页
Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected an... Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas. 展开更多
关键词 CATARACT Cataract ultrasonic emulsification Small incision cataract extracapsular extraction Therapeutic efficacy
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An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L. 被引量:15
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作者 Jingyao Tian Siddique Muhammad +5 位作者 Ai Chen Peng Chen Jinghong Wang Chengwu Yang Hui Yuan Zhensheng Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1735-1741,共7页
In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations an... In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g. 展开更多
关键词 Amorpha fruticosa L. Flavonoid COMPOUNDS ultrasonic extraction Response surface METHODOLOGY
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Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity
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作者 Xinzhu Zhang Ming Song +1 位作者 Weizhuo Xu Wei Xu 《Journal of Polyphenols》 2023年第1期35-47,共13页
The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction condit... The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products. 展开更多
关键词 Aronia melanocarpa phenolic compounds enzymatic extraction ultrasonication antibacterial effect antioxidation effect
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The Optimization of Ultrasonic Extraction Technology of Total Flavonoids in Leaves of Mallotus apelta by Response Surface Analysis Methodology 被引量:9
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作者 Dengfeng ZOU Ruifen FAN +1 位作者 Xiao HUANG Aize XIE 《Medicinal Plant》 CAS 2018年第4期68-72,共5页
[Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assiste... [Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assisted ethanol extraction,and extraction rate of total flavonoids was taken as evaluation index. On the basis of single-factor experiment,Box-Behnken response surface methodology was employed for selecting the optimum extraction process. [Results]The optimum extraction conditions of total flavonoids were as follows: 75% of ethanol concentration,1∶ 25 of ratio of material to liquid,31 min of ultrasonic time. Under these conditions,the extraction rate of total flavonoids was 1. 115%.[Conclusions] The extraction process obtained by response surface methodology was stable,reasonable,accurate and reliable. It was a feasible method to extract the total flavonoids from M. apelta leaves. 展开更多
关键词 Mallotus apelta Total flavonoids ultrasonic extraction Response surface methodology
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Rapid determination of volatile constituents in safflower from Xinjiang and Henan by ultrasonic-assisted solvent extraction and GC-MS 被引量:3
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作者 Ling-Han Jia Yi Liu Yu-Zhen Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第3期213-218,共6页
The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide s... The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide scientific basis for the quality control of safflower. Five different solvents (diethyl ether, ethanol, ethyl acetate, dichloromethane and acetone) were used and compared in terms of number of volatile components extracted and the peak areas of these components in TIC. The results showed that USE could be used as an efficient and rapid method for extracting the volatile components from safflower. It also could be found that the number of components in the TIC of ethyl acetate extract was more than that in the TIC of other solvent ones. Meanwhile, the volatile components of safflower from Xinjiang Autonomous Region and Henan Province of China were different in chemical components and relative contents. It could be concluded that both the extraction solvents and geographical origin of safflower are responsible for these differences. The experimental results also indicated that USE/GC-MS is a simple, rapid and effective method to analyze the volatile oil components of safflower. 展开更多
关键词 SAFFLOWER ultrasonic solvent extraction Gas chromatographymass spectrometry (GC-MS)
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Study on Ultrasonic Extraction of Total Flavonoids from Angelica keiskei Koidzumi 被引量:4
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作者 Yaoming HU Donghai CHU 《Agricultural Biotechnology》 CAS 2016年第3期6-8,共3页
[Objective] This study aimed to optimize the ultrasonic extraction process of total flavonoids from Angelica keiskei Koidzumi. [Method] Using the yield of total flavonoids as an indicator, the ultrasonic extraction pr... [Objective] This study aimed to optimize the ultrasonic extraction process of total flavonoids from Angelica keiskei Koidzumi. [Method] Using the yield of total flavonoids as an indicator, the ultrasonic extraction process of total flavonoids from A. keiskei was optimized by orthogonal experimental design. [ Result ] Among four factors in orthogonal experimental design, extraction time exhibited the most significant effect on the extraction result; ethanol concentration exhib- ited a significant effect on the extraction result; ultrasonic power and solid-to-liquid ratio had no significant effect. The optimal conditions for ultrasonic extraction of total flavonoids from A. keiskei were extraction time of 25 min, ethanol concentration of 80%, ultrasonic power of 60 W, solid-to-liquid ratio of 1:20 (g/ml), under which the yield of total flavonoids reached 1.56%. [ Conclusion] This study provides the basis for further development and utilization of total flavonoids from A. keiskei. 展开更多
关键词 Angelica keiskei Koidzumi Total flavonoids Orthogonal experiment ultrasonic extraction
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Feature extraction of wood-hole defects using wavelet-based ultrasonic testing 被引量:7
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作者 Huiming Yang Lei Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期395-402,共8页
The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drill... The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drilled into 120 elm samples that differed in the number of holes to verify the validity of the method. Wavelet energy moment can reflect the distribution of energy along the time axis and the amount of energy in each frequency band,which can effectively extract the energy distribution characteristics of signals in each frequency band; therefore,wavelet energy moment can replace the wavelet frequency band energy and constitute wood defect feature vectors. A principal component analysis was used to normalize and reduce the dimension of the feature vectors. A total of 16 principal component features were then obtained, which can effectively extract the defect features of the different number of holes in the elm samples. 展开更多
关键词 wavelet defects ultrasonic extracting replace validity identifying verify processed bottleneck
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Ultrasonic Nebulization Extraction Coupled with Gas Chromatography-Mass Spectrometry for Analysis of Volatile Components in Traditional Chinese Patent Medicine 被引量:1
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作者 LIANG Yue WANG Lu WANG Zi-ming YU Cui ZHANG Han-qi SHI Yu-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期203-207,共5页
The ultrasonic nebulization extraction(UNE) was developed and applied to the extraction of volatile components from traditional Chinese patent medicine Xiaoyao Pills. Several parameters of ultrasonic nebulization ex... The ultrasonic nebulization extraction(UNE) was developed and applied to the extraction of volatile components from traditional Chinese patent medicine Xiaoyao Pills. Several parameters of ultrasonic nebulization extraction including the sample particle size, solvent volume, extraction time and ultrasonic power were studied and selected. As a result, 2.4 g of sample with particle size of 80 mesh was extracted with 15 mL of n-hexane for 20 min at an ultrasonic power of 35 W. The volatile components were analyzed by gas chromatography-mass spectrometry (GC-MS) under the optimal conditions and 57 compounds were identified. The precision, repeatability and stability of the proposed method were also studied. Compared with ultrasonic-assisted extraction(UAE) and hydrodistillation(HD) extraction, the proposed method is more efficient, faster and easier to be operated at room temperature with smaller sample and energy consumption. It is suggested that the ultrasonic nebulization extraction can be used as a novel alternative method for the extraction of volatile components from traditional Chinese patent medicine. 展开更多
关键词 ultrasonic nebulization extraction Gas chromatography-mass spectrometry Volatile component Traditional Chinese patent medicine
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FEATURE EXTRACTION OF BONES AND SKIN BASED ON ULTRASONIC SCANNING 被引量:3
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作者 Zheng Shuxian Zhao Wanhua +1 位作者 Lu Bingheng Zhao Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期510-514,共5页
In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning m... In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning method is developed to acquire the bones and skin contours of the residual limb. Using a pig fore-leg as the scanning object, an overlapping algorithm is designed to reconstruct the 2D cross-sectional image, the contours of the bone and skin are extracted using edge detection algorithm and the 3D model of the pig fore-leg is reconstructed by using reverse engineering technology. The results of checking the accuracy of the image by scanning a cylinder work pieces show that the extracted contours of the cylinder are quite close to the standard circumference. So it is feasible to get the contours of bones and skin by ultrasonic scanning. The ultrasonic scanning system featuring no radiation and low cost is a kind of new means of cross section scanning for medical images. 展开更多
关键词 ultrasonic scanning image reconstruction Feature extraction Bones and skin Image accuracy
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A Study on the Ultrasonic Extraction and Antioxidant Activity of Lychee Pericarp Polysaccharides 被引量:1
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作者 Dandan ZHAO Shengyu CHEN +3 位作者 Shaoming LING Bingfang SHI Jinlei ZHANG Li LI 《Asian Agricultural Research》 2016年第7期61-63,68,共4页
The aim was to optimize ultrasonic extraction conditions and study antioxidant activities of lychee pericarp polysaccharides. The effects of extraction temperature,time,ultrasonic power,solid-liquid ratio on polysacch... The aim was to optimize ultrasonic extraction conditions and study antioxidant activities of lychee pericarp polysaccharides. The effects of extraction temperature,time,ultrasonic power,solid-liquid ratio on polysaccharides yield were investigated by single-factor experiment and orthogonal experiment to obtain optimum extraction conditions; the antioxidant activities of lychee pericarp polysaccharides were evaluated by the total antioxidant activity. Optimum extraction process was under extraction temperature of 80 ℃,extraction time of 2. 5 h,ultrasonic power of 180 W,solid-liquid ratio of 1∶ 25 g / m L; the total antioxidant activity was increased with the increasing concentration of polysaccharides. The extraction process is simple and efficient. The extraction rate of lychee pericarp polysaccharides with antioxidant activities is high. 展开更多
关键词 Lychee PERICARP POLYSACCHARIDES ultrasonic extraction ANTIOXIDANT ACTIVITY
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Optimization of Ultrasonic Extraction Process of Polysaccharides from Polyporus umbellatus 被引量:1
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作者 Juanjuan DU Mengting LIU Fei LI 《Agricultural Biotechnology》 CAS 2015年第6期7-9,共3页
[ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbe... [ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbellatus. [ Method ] By single-factor experiment, the ultrasonic extraction process of polyperus pelysac- charides was optimized. [Result] The optimal conditions for ultrasonic extraction of polysaccharides from P. umbeUatus were: solid-liquid ratio 1:40 (g: ml), ex- traction duration 60 rain, extraction temperature 70 ℃, ultrasonic power 100 W. [ Conclusion] Compared with conventional water extraction method, ultrasonic ex- traction could significantly improve the content of polyporus polysaccharides with shorter extraction duration, lower solid-liquid ratio and lower extraction tempera- 展开更多
关键词 Polyporus umbellatus POLYSACCHARIDES ultrasonic extraction Single-factor experiment
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Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques 被引量:9
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作者 LANGYinhai CAOZhengmei NIEXinhua 《Journal of Ocean University of China》 SCIE CAS 2005年第2期173-176,共4页
The application of soxhlet, ultrasonic and accelerated solvent extraction techniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT, p, p'-DDT and p, p'-DDE) in Taihu L... The application of soxhlet, ultrasonic and accelerated solvent extraction techniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT, p, p'-DDT and p, p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits of quantification ranged from 0.002 μg g-1 to 0.004 μg g-1, and the recoveries of organochlorine pesticides with the three extraction techniques were acceptable (> 80.7%). With a mass selective detector,better results were obtained by accelerated solvent extraction using hexane-acetone (1: 1) as compared with soxhlet and ultrasonic extraction. It was shown that the accelerated solvent extraction was the optimum technique for the analysis of organochlorine pesticides in sediments. The general features of the three extraction techniques are also presented. 展开更多
关键词 有机氯杀虫剂 太湖沉积 水体污染 超声萃取
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The Optimization of Ultrasonic Extraction Process of Total Flavonoids from Rhodiola Crenulata by Response Surface Method 被引量:9
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作者 Xuedong GU Yajing SUN +2 位作者 Changzhong MA Fumin CHI Lin YANG 《Medicinal Plant》 2017年第6期33-39,共7页
[Objectives]To study the optimal extraction process of total flavonoids in Rhodiola rosea L.,and further facilitate the development and utilization of Rhodiola rosea L. [Methods]With Rhodiola crenulata as raw material... [Objectives]To study the optimal extraction process of total flavonoids in Rhodiola rosea L.,and further facilitate the development and utilization of Rhodiola rosea L. [Methods]With Rhodiola crenulata as raw material,ethanol as extractant,ultrasonic extraction as the extraction method,the single factor method was first used for preliminary investigation of effect of ethanol volume fraction,solid-liquid ratio,extraction temperature and extraction time on the flavonoids extraction rate,and then the Box-Behnken response surface method was used to optimize the extraction process of total flavonoids in R. crenulata. [Results] The optimal extraction conditions: ethanol concentration of 72%;solid-liquid ratio of 1∶ 43; extraction temperature of 66℃; extraction time of 50 min. Under these conditions,the extraction rate of total flavonoids from R. crenulata was 2. 591%. [Conclusions] The results showed that the method of response surface was reasonable and feasible for the optimization of ultrasonic extraction of total flavonoids from R. crenulata. 展开更多
关键词 RHODIOLA crenulata TOTAL FLAVONOIDS ultrasonic extraction RESPONSE surface method
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Optimization on Ultrasonic Extraction Method of Total Flavonoids for Liriodendron chinense Sarg.×L.tulipifera L. by Response Surface Methodology (RSM) 被引量:1
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作者 Yi JIANG Xuqin REN +2 位作者 Gang LI Guoqing PAN Run ZHUO 《Agricultural Biotechnology》 CAS 2019年第5期132-135,共4页
With the leaves,bark and roots of Liriodendron chinense Sarg.× L.tulipifera L.as experiment materials,the ultrasonic-assisted extraction conditions of total flavonoids were optimized by response surface Box-Behnk... With the leaves,bark and roots of Liriodendron chinense Sarg.× L.tulipifera L.as experiment materials,the ultrasonic-assisted extraction conditions of total flavonoids were optimized by response surface Box-Behnken test design.Ultrasonic time and liquid-to-solid ratio had significant effects on the extraction amount of flavonoids from the leaves of L.chinense Sarg.× L.tulipifera L.;ultrasonic temperature and liquid-to-solid ratio had an interaction on the extraction amount of flavonoids;and the optimum ultrasonic time,temperature and liquid-to-solid ratio for the extraction of flavonoids from leaves of L.chinense Sarg.× L.tulipifera L.were 19.82 min,28.60 ℃ and 9.48 ml/g,respectively.Ultrasonic time,temperature and liquid-to-solid ratio had significant effects on the extraction amount of flavonoids from L.chinense Sarg.× L.tulipifera L.;there was a significant interaction between any two of the factors,which had a significant effect on the extraction of flavonoids;and the optimum extraction parameters for flavonoids in the bark were the ultrasonic time of 33.66 min,the ultrasonic temperature at 32.85 ℃ and the liquid-to-solid ratio of 11.39 ml/g.Ultrasonic time and liquid-to-solid ratio had significant effects on the extraction of flavonoids from roots;there was a significant interaction between ultrasonic time and liquid-to-solid ratio and between ultrasonic temperature and liquid-to-solid ratio;and the optimum extraction parameters for flavonoids from the roots of L.chinense Sarg.× L.tulipifera L.were the ultrasonic time of 32.38 min,the ultrasonic temperature at 25.0 ℃ and the liquid-to-solid ratio of 8.00 ml/g.The results of the three models were stable.The models are feasible and have good application value. 展开更多
关键词 Response surface METHODOLOGY LIRIODENDRON chinense Sarg.× L. tulipifera L. TOTAL FLAVONOIDS ultrasonic extraction
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Ultrasonic Extraction of Polysaccharides from Laminaria japonica and Their Antioxidative and Glycosidase Inhibitory Activities 被引量:6
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作者 WAN Peng YANG Xiaoman +4 位作者 CAI Bingna CHEN Hua SUN Huili CHEN Deke PAN Jianyu 《Journal of Ocean University of China》 SCIE CAS 2015年第4期651-662,共12页
In the present study, ultrasonic extraction technique(UET) is used to improve the yield of polysaccharides from Laminaria japonica(LJPs). And their antioxidative as well as glycosidase inhibitory activities are invest... In the present study, ultrasonic extraction technique(UET) is used to improve the yield of polysaccharides from Laminaria japonica(LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design(BBD) combined with response surface methodology(RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80℃ and ratio of material to solvent at 1:50(g m L-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield(5.75% ± 0.3%) is close to the predicted result(5.67%) with no significant difference(P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides(LJP) and two major ethanol precipitated fractions(LJP1 and LJP2) are in a concentration-dependent manner. LJP2(30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals(66.09% ± 2.19%, 3.0 mg m L-1). Also, the inhibitory activity against α-glucosidase(59.08% ± 3.79%, 5.0 mg m L-1) is close to that of acarbose(63.99% ± 3.27%, 5.0 mg m L-1). LJP1(30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals(99.80% ± 0.00%, 3.0 mgm L-1) and moderate α-glucosidase inhibitory activity(47.76% ± 1.92%, 5.0 mg m L-1). LJP shows the most remarkable DPPH scavenging activity(66.20% ± 0.11%, 5.0 mg m L-1) but weakest α-glucosidase inhibitory activity(37.77% ± 1.30%, 5.0 mg m L-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of diabetes. This study provides scientific evidence and advances in the preparation technology and a hypoglycemic activities evaluation method for seaweed polysaccharides, especially glycosidase inhibition in combination with an antioxidative activity evaluation method. 展开更多
关键词 生物活性多糖 超声波提取 抗氧化活性 海带多糖 BOX-BEHNKEN设计 Α-葡萄糖苷酶 羟基自由基 抑制活性
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Simultaneous Determination of Four Estrogens in Compost Based on Ultrasonic Solvent Extraction, Solid-Phase Extraction Clean-Up and Analysis by UHPLC-MS/MS 被引量:1
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作者 Miguel Ángel López Zavala Blanca Nelly Flores Arriaga Naoyuki Funamizu 《American Journal of Analytical Chemistry》 2016年第5期434-445,共12页
A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost sample... A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco&reg;<sup></sup> and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC Kinetex<sup>TM</sup> 2.6 μm XB-C18 100 &Aring;LC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g<sup>-1</sup> and 2 ng·g<sup>-1</sup> for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively. 展开更多
关键词 COMPOST ESTROGENS Solid-Phase extraction Clean-Up UHPLC-MS/MS ultrasonic Solvent extraction
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Antioxidant and hepatoprotective effects of Ajuga nipponensis extract by ultrasonic-assisted extraction 被引量:3
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作者 Chang-Wei Hsieh Wen-Ching Ko +3 位作者 Wai-Jane Ho Chao-Kai Chang Guo-Jhou Chen Jen-Chieh Tsai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第5期409-414,共6页
Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction paramet... Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction parameters for ecdysterones and flavonoids. Finally, the hepatoprotective abilities of A. nipponensis extracts were evaluated by CCl_4-induced animal models. Results:Maximum yields of flavonoids(7.87±0.10) mg/g and ecdysterones(0.73±0.02) mg/g could be obtained when the extraction time was 50 min, the extraction temperature was 60 ℃, and the ratio of sample to 70%(v/v) ethanol was 1:20(w/w). The antioxidant property of A. nipponensis was correlated to the concentration of its extracts. At 5 mg/m L, A. nipponensisextract scavenged 84.8% of DPPH radical and had absorbance values of 2.43±0.04 reducing power. Upon CCl_4-induced liver injury, glutamic oxaloacetic transaminase and glutamic pyruvic transaminase decreased significantly after the mice were treated with A. nipponensis. Histological researches also explained that A. nipponensis reduced the extent of liver lesions induced by CCl_4. Conclusions: A. nipponensis exhibited potent antioxidant activity in chemical experimental models and hepatoprotective effect against CCl_4-induced liver damage. 展开更多
关键词 Ajuga nipponensis ultrasonic-ASSISTED extraction ORTHOGONAL test ANTIOXIDANT HEPATOPROTECTION
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Optimization of Ultrasonic-Assisted Extraction Process of Polysaccharides from American Ginseng and Evaluation of Its Immunostimulating Activity 被引量:6
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作者 YANG Xiu-shi WANG Li-jun +2 位作者 DONG Chuan Edmund Man King Lui REN Gui-xing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2807-2815,共9页
Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason... Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography (GC) analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides. 展开更多
关键词 ultrasonic-assisted extraction POLYSACCHARIDES American ginseng response surface methodology immunostimulating activity
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Optimization of Ultrasonic Extraction and Clean-up Protocol for the Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments by High-performance Liquid Chroma-tography Coupled with Fluorescence Detection 被引量:1
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作者 PENG Xuewei YAN Guofang +3 位作者 LI Xianguo GUO Xinyun ZHOU Xiao WANG Yan 《Journal of Ocean University of China》 SCIE CAS 2012年第3期331-338,共8页
The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were pu... The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were purified with a miniaturized silica gel chromatographic column and analyzed with high performance liquid chromatography (HPLC) with a fluorescence detector. Ultrasonication with methanol-dichloromethane (2:1, v/v) mixture gave higher extraction efficiency than that with dichloromethane. Among the three elution solvents used in clean-up step, dichloromethane-hexane (2:3, v/v) mixture was the most satisfactory. Under the optimized conditions, the recoveries in the range of 54.82% to 94.70% with RSDs of 3.02% to 23.22% for a spiked blank, and in the range of 61.20% to 127.08% with RSDs of 7.61% to 26.93% for a spiked matrix, were obtained for the 15 PAHs studied, while the recoveries for a NIST standard reference SRM 1941b were in the range of 50.79% to 83.78% with RSDs of 5.24% to 21.38%. The detection limits were between 0.75 ng L-1 and 10.99 ng L-1for different PAHs. A sample from the Jiaozhou Bay area was examined to test the established methods. 展开更多
关键词 高效液相色谱法 超声提取工艺 海洋沉积物 荧光检测器 多环芳烃 优化条件 测定 清理
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Optimization of Ultrasonic Extraction Process of Total Flavonoids from Mulberry Leaves by Orthogonal Experiment
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作者 Xianling WANG Yaning WANG +1 位作者 Xiuxiu YANG Min XU 《Agricultural Biotechnology》 CAS 2014年第4期12-13,共2页
In this study, by using mulberry leaves as raw materials, ultrasonic extraction process of total flavonoids from mulberry leaves was optimized by orthogonal experiment. Results showed that the maximum yield of total f... In this study, by using mulberry leaves as raw materials, ultrasonic extraction process of total flavonoids from mulberry leaves was optimized by orthogonal experiment. Results showed that the maximum yield of total flavonoids (6.1% ) was obtained from mulberry leaves with addition of 45 times the volume of water by ultrasonic extraction at 55 ℃ for three times, 55 min each. According to the verification test, the optimized technical process was reasonable and feasible with high stability. 展开更多
关键词 Orthogonal experiment Mulberry leaves Total flavonoids ultrasonic extraction
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