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Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis
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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
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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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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
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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
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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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Lithium extraction from hard rock lithium ores(spodumene,lepidolite,zinnwaldite,petalite):Technology,resources,environment and cost 被引量:6
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作者 Tian-ming Gao Na Fan +1 位作者 Wu Chen Tao Dai 《China Geology》 CAS CSCD 2023年第1期137-153,共17页
Lithium production in China mainly depends on hard rock lithium ores,which has a defect in resources,environment,and economy compared with extracting lithium from brine.This paper focuses on the research progress of e... Lithium production in China mainly depends on hard rock lithium ores,which has a defect in resources,environment,and economy compared with extracting lithium from brine.This paper focuses on the research progress of extracting lithium from spodumene,lepidolite,petalite,and zinnwaldite by acid,alkali,salt roasting,and chlorination methods,and analyzes the resource intensity,environmental impact,and production cost of industrial lithium extraction from spodumene and lepidolite.It is found that the sulfuric acid method has a high lithium recovery rate,but with a complicated process and high energy consumption;alkali and chlorination methods can directly react with lithium ores,reducing energy consumption,but need to optimize reaction conditions and safety of equipment and operation;the salt roasting method has large material flux and high energy consumption,so require adjustment of sulfate ratio to increase the lithium yield and reduce production cost.Compared with extracting lithium from brine,extracting lithium from ores,calcination,roasting,purity,and other processes consume more resources and energy;and its environmental impact mainly comes from the pollutants discharged by fossil energy,9.3-60.4 times that of lithium extracted from brine.The processing cost of lithium extraction from lepidolite by sulfate roasting method is higher than that from spodumene by sulfuric acid due to the consumption of high-value sulfate.However,the production costs of both are mainly affected by the price of lithium ores,which is less competitive than that of extracting lithium from brine.Thus,the process of extracting lithium from ores should develop appropriate technology,shorten the process flow,save resources and energy,and increase the recovery rate of related elements to reduce environmental impact and improve the added value of by-products and the economy of the process. 展开更多
关键词 Lithium ore Lithium extraction Comprehensive utilization Acid method alkali method Salt roasting method Chlorination method Mineral exploration engineering
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Effect of alkali extraction on pit membranes and liquid uptake of four commercial softwoods 被引量:1
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作者 WANGYue WANGMing-zhi 《Forestry Studies in China》 CAS 2012年第2期160-164,共5页
The present study examined the effect of alkali extraction on pit membranes (PMs) and liquid uptake of four conifers. Af- ter alkali extraction, the deposits around the PMs almost dissolved in Cunninghamia lanceolat... The present study examined the effect of alkali extraction on pit membranes (PMs) and liquid uptake of four conifers. Af- ter alkali extraction, the deposits around the PMs almost dissolved in Cunninghamia lanceolata Hook. and Cryptomeriajaponica D. Don wood which showed good liquid uptake. In contrast, in Larix leptolepis Gordon and Pseudotsuga menziesii Franco, although the tori adhered strongly to the pit aperture preventing liquid transportation, the liquid uptake of the woods improved markedly. More- over, the combined treatment of alkali extraction-transverse compression had no synergistic effect in improving liquid uptake. These results demonstrate that alkali extraction is effective in improving the liquid uptake of wood. 展开更多
关键词 pit membrane alkali extraction liquid uptake
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Green and Effective Ammonium Carbonate-assisted Process for Drying Hemicellulose Obtained through Alkali Extraction of Bleached Bamboo Kraft Pulp 被引量:1
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作者 Xiaoqi Gong Zongwei Zhang +4 位作者 Yonghao Ni Xinhua Ouyang Lihui Chen Liulian Huang Huichao Hu 《Paper And Biomaterials》 CAS 2021年第1期1-10,共10页
Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually prese... Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films. 展开更多
关键词 bamboo kraft pulp HEMICELLULOSE alkali extraction ammonium carbonate drying process dissolving pulp
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STUDY ON TREATING ALKALI EXTRACTION-STAGE EFFLUENT FOR COLOR REMOVAL BY MICRO-ELECTROLYSIS METHOD
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作者 XianyingXiao ZhonghaoChen YuancaiChen 《天津科技大学学报》 CAS 2004年第A02期177-180,共4页
The micro-electrolysis technology was applied in the decolorizing treatment of bleaching E-stage effluent and the influencing factors were discussed in this paper. The initial pH and the retention time were main facto... The micro-electrolysis technology was applied in the decolorizing treatment of bleaching E-stage effluent and the influencing factors were discussed in this paper. The initial pH and the retention time were main factors influencing the color removal rate, in addition, adding air and enough pH for neutralization were necessary for the treatment. The test showed that the decolorizing result was efficient by micro-electrolysis treatment when adding air, initial pH was 3, 20 minutes of reaction time, the final pH 10 for neutralization. The color removal rate was up to 90%. The chance of ultraviolet absorption spectrum also demonstrated the mechanism of color removal in the wastewater treatment. 展开更多
关键词 微电解 脱色 碱性萃取废水 PH值 废水处理
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Isolation of Hemicellulose from Wood Chips via Extraction with Kraft Green Liquor 被引量:2
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作者 SUN Hui XU Ying-kai XU Guo-zhi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期667-671,共5页
The present paper covers the extraction of hemicelluloses from woods, i.e., Eucalyptus Globulus, white fir and Douglas fir via green liquor pretreatment and alkali post-treatment with sodium hydroxide. The effects of ... The present paper covers the extraction of hemicelluloses from woods, i.e., Eucalyptus Globulus, white fir and Douglas fir via green liquor pretreatment and alkali post-treatment with sodium hydroxide. The effects of such extraction conditions as extraction time, temperature on the yields of hemicellulose and the degree of deliginification were investigated. Sugar analyses using Dionex indicate that xylose, glucose and mannose are the main sugar types present in the hemicellulose from Eucalyptus. Other sugar components such as arabinose and galactose were also found in Dogulas fir hemicellulose. The highest yield of hemicellulose was 8.4% for Eucalyptus extracted with green liquor at 130 ℃ for 3.5 h. Further sodium hydroxide extraction for 5 h gave a hemicellulose yield of about 20%. The use of green liquor for the extraction of wood hemicellulose is believed to be the first attempt. 展开更多
关键词 HEMICELLULOSE LIGNIN WOOD Green liquor alkali extraction
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Extraction and Purification Process Optimization and Antioxidant Activity in vitro of Flavonoids in Amaranthus caudatus L. 被引量:3
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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
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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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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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Optimizing the Extraction of Anthocyanins from Pitaya(Hylocereus undatus)Pericarp 被引量:1
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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
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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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Survey of Intracellular Protein Extraction Methods from Pichia pastoris
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作者 Yuli Wang Yuansen Hu +3 位作者 Yang Lei Yangyong Lv Le Wang Hongwei Wei 《World Journal of Engineering and Technology》 2015年第4期1-6,共6页
The broken efficiency of cell wall and the release amount of Pichia pastoris intracellular protein under different cell breaking conditions were investigated in this paper. The results showed that broken efficiency us... The broken efficiency of cell wall and the release amount of Pichia pastoris intracellular protein under different cell breaking conditions were investigated in this paper. The results showed that broken efficiency using hot alkali combined with high-pressure homogenizing method was higher than that of enzyme hydrolysis, hot alkali treatment and high-pressure homogenation, respectively. Suspended medium had little effect on the broken efficiency of yeast cell, but had significant effect on the protein release yield. The results indicated that optimal condition for intracellular proteins extraction was 30% (wet weight, w/v) of yeast cells suspend in 50 mM phosphate buffer (pH 10.0), water bathed at 60?C for 2 hours, homogenized twice at 100 MPa pressure. The broken efficiency of Pichia pastoris cell could reach 87.6% and the protein yield was 35.48 g per 100 g cells. 展开更多
关键词 PICHIA PASTORIS HIGH Temperature and alkali Treatment HIGH Pressure Homogeniza-Tion Cell Wall BREAKING Protein extraction
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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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鲍鱼脏器碱提多糖的分离纯化、结构表征及抗氧化活性研究 被引量:1
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作者 林志超 潘晓明 +3 位作者 吴启赐 薛钰 黄家福 潘裕添 《食品工业科技》 CAS 北大核心 2024年第4期53-60,共8页
目的:分离纯化鲍鱼脏器碱提多糖(alkali-extracted abalone vscera polysaccharides,Aavp),并研究其结构和抗氧化活性,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉获得鲍鱼脏器碱提粗多糖,经DEAE Sepharose Fast ... 目的:分离纯化鲍鱼脏器碱提多糖(alkali-extracted abalone vscera polysaccharides,Aavp),并研究其结构和抗氧化活性,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉获得鲍鱼脏器碱提粗多糖,经DEAE Sepharose Fast Flow和Sephacryl S-400 HR纯化得到高纯度多糖,并利用气相色谱、高效液相色谱、红外光谱和热重分析仪等工具分析其结构及抗氧化活性。结果:粗多糖纯化后得到四个组分,包括Aavp Ia、Aavp Ib、Aavp IIa和Aavp IIb,其中Aavp IIa得率较高,选择其进一步进行结构分析。分析发现,Aavp IIa由木糖和半乳糖组成,分子量为166513 Da;糖苷键构型为α型,组成如下:半乳糖1→4糖苷键摩尔百分比为11.81%,半乳糖1→3糖苷键为34.14%,半乳糖1→2糖苷键为10.14%;木糖1→3糖苷键摩尔百分比为33.85%,1→2和1→4糖苷键共占10.06%。热重分析显示,Aavp IIa在226.4-332.6℃下断裂分解,热失重率为43.65%。抗氧化实验显示Aavp IIa对O2-·的清除率为85.89%,对DPPH·的清除率为62.17%,具有一定的抗氧化活性。结论:提取的鲍鱼脏器碱提多糖是一类杂多糖,并具有一定的抗氧化活性。 展开更多
关键词 鲍鱼脏器 碱提多糖 单糖组成 热重分析 抗氧化活性
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响应面优化提取玄参碱溶性多糖及对高眼压小鼠视网膜的影响
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作者 张一文 刘晓庆 沈伟 《中国食品添加剂》 CAS 2024年第4期208-218,共11页
采用单因素及响应面优化微波提取玄参碱溶性多糖(简称多糖)工艺,并对高眼压症小鼠进行21天灌胃不同剂量多糖后测定小鼠眼压变化和通过研究其视网膜结构变化、氧化反应和炎症反应初步探索其机制。结果表明多糖的最佳提取条件为:微波功率4... 采用单因素及响应面优化微波提取玄参碱溶性多糖(简称多糖)工艺,并对高眼压症小鼠进行21天灌胃不同剂量多糖后测定小鼠眼压变化和通过研究其视网膜结构变化、氧化反应和炎症反应初步探索其机制。结果表明多糖的最佳提取条件为:微波功率400 W,微波时间16 min,微波温度72℃,NaOH浓度5.5%,并在料液比1/25(g/mL),在此条件下多糖提取率为18.75 mg/g。多糖可以降低小鼠的眼压和有效保护视网膜结构,其机制是通过提高SOD、GSH-px抗氧化酶类活性来提高视网膜抗氧化能力和抑制TNF-α、IL-1β和IL-6炎症因子的表达,是一种潜在的功能性食品添加剂。 展开更多
关键词 玄参 碱溶性多糖 微波辅助提取 高眼压 视网膜
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鲍鱼脏器碱提多糖制备工艺及对L929细胞H_(2)O_(2)氧化损伤的修复活性
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作者 吴启赐 林志超 +3 位作者 潘晓明 薛钰 黄家福 潘裕添 《食品工业科技》 CAS 北大核心 2024年第13期204-211,共8页
目的:优化鲍鱼脏器碱提多糖(Alkali-extracted abalone viscera polysaccharides,Aavp)提取工艺,并研究纯化Aavp对L929细胞H_(2)O_(2)氧化损伤的预防和修复作用,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉法获... 目的:优化鲍鱼脏器碱提多糖(Alkali-extracted abalone viscera polysaccharides,Aavp)提取工艺,并研究纯化Aavp对L929细胞H_(2)O_(2)氧化损伤的预防和修复作用,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉法获得鲍鱼脏器碱提粗多糖,并利用响应面法优化提取工艺,最后分析纯化Aavp对L929细胞H_(2)O_(2)氧化损伤的预防和修复能力。结果:鲍鱼脏器碱提粗多糖最佳提取工艺条件为:料液比1:150 g/mL,提取时间2 h,提取温度70℃,在此条件下,鲍鱼脏器碱提粗多糖得率为8.57%。在L929细胞H_(2)O_(2)氧化损伤预防试验中,不同剂量的纯化Aavp(20、50和100μg/mL)对L929细胞氧化损伤均具有极显著的预防作用(P<0.001),但没有表现出剂量效应,其中中剂量组(50μg/mL)的细胞存活率最高(71.94%±3.08%),略优于阳性对照的维生素E组,但无显著性差异。在修复试验中,不同剂量的纯化Aavp(20、50和100μg/mL)对L929细胞氧化损伤均具有极显著的修复效果(P<0.001),并呈现剂量效应,而高剂量组(100μg/mL)的细胞存活率最高(90.93%±1.17%),略高于阳性对照的维生素E组(87.96%±3.05%)。结果表明鲍鱼脏器碱提多糖对L929细胞H_(2)O_(2)氧化损伤具有出较好的预防和修复作用。结论:鲍鱼脏器碱提多糖具有一定的L929细胞H_(2)O_(2)氧化损伤修复能力。 展开更多
关键词 鲍鱼脏器 碱提多糖 响应面优化 氧化损伤
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