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Liquid–liquid extraction of levulinic acid from aqueous solutions using hydrophobic tri-n-octylamine/alcohol-based deep eutectic solvent
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作者 Yinglin Mai Xiaoling Xian +4 位作者 Lei Hu Xiaodong Zhang Xiaojie Zheng Shunhui Tao Xiaoqing Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期248-256,共9页
Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of fields.However,separation and purification of LA from aqueous solution or a... Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of fields.However,separation and purification of LA from aqueous solution or actual hydrolysate continues to be a challenge.Among various downstream separation technologies,liquid-liquid extraction is a low-cost,effective,and simple process to separate LA.The key breakthrough lies in the development of extractants with high extraction efficiency,good hydrophobicity,and low cost.In this work,three hydrophobic deep eutectic solvents(DESs)based on tri-n-octylamine(TOA)as hydrogen bond acceptor(HBA)and alcohols(butanol,2-octanol,and menthol)as hydrogen bond donors(HBDs)were developed to extract LA from aqueous solution.The molar ratios of HBD and HBA,extraction temperature,contact time,solution pH,and initial LA concentration,DES/water volume ratios were systematically investigated.Compared with 2-octanol-TOA and menthol-TOA DES,the butanol-TOA DES exhibited the superior extraction performance for LA,with a maximum extraction efficiency of 95.79±1.4%.Moreover,the solution pH had a great impact on the LA extraction efficiency of butanol-TOA(molar ratio=3:1).It is worth noting that the extraction equilibrium time was less than 0.5 h.More importantly,the butanol-TOA(3:1)DES possesses good extraction abilities for low,medium,and high concentrations of LA. 展开更多
关键词 extraction SEPARATION Levulinic acid Deep eutectic solvents HYDROPHOBIC Aqueous solution
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Extraction of Cinnamomum longepaniculatum deciduous leaves essential oil using solvent-free microwave extraction: Process optimization and quality evaluation
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作者 Chunlei Wei Chuyun Wan +1 位作者 Fenghong Huang Tingting Guo 《Oil Crop Science》 CSCD 2023年第1期7-15,共9页
The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodolog... The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodology(RSM).A Box-Behnken design(BBD)was applied to evaluate the effects of three independent variables:moisture content(A:54%–74%),microwave power(B:300–500 W)and microwave time(C:20–40 min),on the extraction yield of essential oil.The compounds of the essential oils obtained by SFME,hydro-distillation and microwaveassisted hydro-distillation(MADE)were identified by gas chromatography-mass spectrometry(GC-MS),and the total lipids of C.longepaniculatum fresh leaves and deciduous leaves were analyzed.The correlation analysis of the response regression model indicated that quadratic polynomial model could be employed to optimize the extraction of essential oil.The optimal extraction condition was A:58%,B:400 W and C:28 min.In the optimal condition,the maximum extraction yield was 4.475 mL/100 g dw and higher than that by MADE.The main compound of the essential oil was eucalyptol(63.54%),and total oxygenated compounds was 78.95%,mainly caused by SFME and the metabolism of endophytic bacteria with decreasing content of phospholipids and fatty acids.Analysis of variance under the extraction condition illustrated high fitness of the model and the success of RSM for optimizing and reflecting the expected process condition.SFME combined with moisture regulation was an effective method for extracting essential oil from C.longepaniculatum deciduous leaves. 展开更多
关键词 Cinnamomum longepaniculatum Deciduous leaves Solvent-free microwave extraction Response surface methodology extraction yield Essential oil
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Protective Effect of Ethanol Extract from Sweet Potato Leaves on CCL_(4)-Induced Liver Injury in Mice
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作者 Chenchen HUANG Haihua LU +5 位作者 Ting ZHAO Xiangting QIN Ting WEI Yingjun HE Suoyi HUANG Zhongshi HUANG 《Medicinal Plant》 CAS 2023年第5期49-51,共3页
[Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose ... [Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose extract group(200 mg/kg),low-dose extract group(100 mg/kg)and positive control group(2 mg/kg colchicine),with 5 mice in each group.All groups except the blank group were given intraperitoneal injection of 20%CCl 4 olive oil solution(2 mL/kg),and the blank group was given the same dose of olive oil solution three times a week.After 4 weeks,each administration group was given the corresponding dose of drugs(10 mL/kg),and the blank group and model group were given the corresponding amount of normal saline for 2 weeks.After the last intragastric administration,fasting was required,but water was allowed,blood was taken from eyeballs,and upper serum was taken by static centrifugation.Serum AST,ALT,CRP,IL-6 and SOD levels were detected by the kit.[Results]Compared with the blank group,the serum AST and ALT levels in the model group were significantly increased;compared with the model group,the ethanol extract of sweet potato leaves could decrease the levels of ALT,AST,CRP,IL-6 and increase the level of SOD in serum.[Conclusions]The ethanol extract of sweet potato leaves had protective effect on the mice with liver injury induced by CCl_(4),and its mechanism may be to protect the liver by lowering enzymes,inhibiting inflammation and antioxidant stress. 展开更多
关键词 Sweet potato leaves Ethanol extract Liver injury Protective effect
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Research Progress in the Extraction and Application of Flavonoids from Ginkgo biloba Leaves
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作者 Lili SONG Kaili LI 《Meteorological and Environmental Research》 CAS 2023年第2期50-52,56,共4页
Ginkgo biloba resources in China are enormous. With the demand of the market, the preparation and application of flavonoids have become a current research hotspot. The main active substances in G. biloba leaves, flavo... Ginkgo biloba resources in China are enormous. With the demand of the market, the preparation and application of flavonoids have become a current research hotspot. The main active substances in G. biloba leaves, flavonoids, have various functional activities and are widely used in fields such as food, medicine, cosmetics, feed, etc. In this paper, the introduction, functional activity, extraction methods, and application research of flavonoids from G. biloba leaves are reviewed, and the development prospects of flavonoids from G. biloba leaves are expected. 展开更多
关键词 Flavonoids from G.biloba leaves Functional activity extraction method Application and prospects
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Preliminary Findings on Anticancer and Lymphocyte Stimulated Activities of Bioactive Compounds Extracted from Vietnam Carica papaya Leaves
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作者 Do Thi Hoa Vien Do Thi Thao 《Journal of Food Science and Engineering》 2013年第9期447-452,共6页
In this study, the target bioactive compounds (e.g., alkaloids, flavonoids, saponins and other polar compounds) in Vietnamese Caricapapaya leaves were extracted. The cytotoxic activities of the papaya leaves extract... In this study, the target bioactive compounds (e.g., alkaloids, flavonoids, saponins and other polar compounds) in Vietnamese Caricapapaya leaves were extracted. The cytotoxic activities of the papaya leaves extracts on the selected tumor cell lines, such as lung cancer cell line LU-1, carcinoma cell line KB, breast cancer cells MCF7 and leukemia cell line HL-60, were examined. Preliminary findings showed a high inhibitive activity of papaya leave extracts against the four tested tumor cell lines at the concentration of 100 μg/mL. Out of the bioactive compounds in papaya leaves extract, alkaloids showed the highest inhibitive activity (105.95% on MCF7 and 91.86% on LU-1), followed by polar compounds (62.88% on LU-1 and 21.80% on KB), and saponins (59.74% on MCF7 and 25.25% on LU-1). Flavonoids has the lowest inhibitive activity on cell lines (e.g., 45.51% on MCF7 and 20.32% on LU-1). Taken together, the results suggest that alkaloids have a relatively high inhibitive activity on the selected tumor cell lines and their stimulated concentration at 50% (IC50) values for on MCF7 and KB were 24.67 μg/mL and 33.56 μg/mL, respectively. However, the result pointed out the immunostimulatory ability of only polar compounds and saponins which could stimulate the growth of in vitro lymphocytes but not flavonoids and alkaloids. The SC50 (stimulated concentration at 50%) values of polar compounds and saponins were 287.87μg/mL and 192.99 μg/mL, respectively. 展开更多
关键词 Papaya leaves extract polar compounds ALKALOIDS SAPONINS flavonoids cytotoxic assay tumor cell line lymphocytestimulated activity
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Synergistic extraction of zinc from ammoniacal solutions using β-diketone mixed with CYANEX923 or LIX84I 被引量:5
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作者 胡久刚 陈启元 +1 位作者 胡慧萍 尹周澜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1217-1223,共7页
The extraction behaviors of zinc from ammoniacal solutions were investigated using β-diketone (HA) and their mixtures with CYANEX923 or LIX84I. The effects of pH, total ammonia concentration, extractant concentrati... The extraction behaviors of zinc from ammoniacal solutions were investigated using β-diketone (HA) and their mixtures with CYANEX923 or LIX84I. The effects of pH, total ammonia concentration, extractant concentration, anion species and temperature on zinc extraction were examined. The synergistic mechanism was discussed with regard to the structure of extractant and the extracted zinc complexes. It is found that the increase of total ammonia concentration and pH inhibits zinc extraction for all extraction systems due to the formation of zinc ammine complexes in aqueous phase. This effect of HA with CYANEX923 is evidently smaller than that of HA with LIX84I or HA alone system. Effect of anion species on the zinc extraction by HA with CYANEX923 can be neglected, but this effect of HA alone and the mixture of HA with LIX84I decreases in the order of (NH4)2SO4 〉 NH4NO3 〉 NH4Cl. 展开更多
关键词 synergistic extraction ZINC ammoniacal solution Β-DIKETONE CYANEX923 LIX84I
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves Non-target organisms Safety evaluation
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Anti-insect Bioactivity of the Extracts from Cichorium intybus L. Leaves
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作者 孙娈姿 杜金鸿 +2 位作者 呼天明 王佺珍 崔健 《Agricultural Science & Technology》 CAS 2010年第6期99-102,共4页
In order to develop a new plant-source insecticide,some active components from Cichorium intybus L.were extracted with mineral ether,ethyl ether,ethyl acetate,respectively.It were testified the effects of the componen... In order to develop a new plant-source insecticide,some active components from Cichorium intybus L.were extracted with mineral ether,ethyl ether,ethyl acetate,respectively.It were testified the effects of the components on the development of Mythimna separate Walker and anti-feeding by feeding and weighting method.The results showed that the body weight of the larvae fed by the extracts with organic solvents was significantly lower than the control;the body weight of the larvae fed by the extracts with organic solvents was significantly different in different solvents in 3-5 days.The corrected mortality of the ethyl acetate treatment was the highest(52.05%),and the development period of the larvae treated by ethyl acetate was about 4-10 days longer than the control and the corresponding pupating rate was the lowest(43.30%).Therefore,the effect of ethyl acetate extract was most significant.Moreover,the pupa weight of the treatments was little more than the control.The extracts from Cichorium intybus L.leaves had highest bioactivity mainly in anti-feeding activity on Mythimna separate Walker. 展开更多
关键词 Cichorium intybus L.leaves extractIONS Anti-insect bioactivity DEVELOPMENT
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Comparison of anti-atherosclerotic effects of two different extracts from leaves of Mallotus furetianus 被引量:15
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作者 Liu Yueli Wang Liqun +2 位作者 Wu Haitao Lin Lianbo Yi Xinan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第11期878-882,共5页
Objective:To compare the anti-atherosclerotic effects of two different extracts from the leaves of Mallotus fiiretianus by using rat model of atherosclerosis.Methods:The air-flriefl powdered Mallotus fiiretianus leave... Objective:To compare the anti-atherosclerotic effects of two different extracts from the leaves of Mallotus fiiretianus by using rat model of atherosclerosis.Methods:The air-flriefl powdered Mallotus fiiretianus leaves were extracted with ethanol and then evaporated.The ethanol extract was experienced Diaion HP-20 CC with a gradient of MeOH and H<sub>2</sub>O(50:50,100:0,v/v) and two fractions,Mallotus fiiretianus A(Mf A) and Mallotus fiiretianus B(MfB) were obtained.RaLs were divided into control,atherosclerosis and vitamin E,Mf A and Mf B treated groups.Atherosclerotic model was established by administering u loading dose of vitamin D<sub>3</sub> and feeding standard diet enriched with 2%cholesterol,0.5%porcine chelate,0.2%methimazole,5%sugar,10%pork fat. Vitamin E(0.20 g/kg),Mf A(0.053 g/kg),Mf B(0.057 g/kg)(with the potential) were administered to interfere with the development of atherosclerosis.After 9 weeks,rats were sacrificed and the blood lipid as well as composition of bile was examined.In addition,the thoracic aorta was harvested to evaluate histological changes and the intima-media thickness ratio.Results: Atherosclerosis model was successfully established,administration of vitamin E,Mf A and Mf B increased excretion of total bilirubin in bile,decreased triglycridc(TO),total cholesterol(TC), low density lipoprotein-cholesterol(LDL-C) level,enhanced ratio of high density lipoprotein-cholesterol and LDL-C in blood,improved histological changes and diminished intimamedia thickness ratio of thoracic aorta in atherosclerotic rats.As for the difference in antiatherosclerotic effects between Mf A and MfB,Mf A may be more powerful in declining TG level and Mf B may be more effective in decreasing TC level.Conclusions:The two different extracts. Mf A and Mf B can prevent the development of atherosclerosis.In detail,Mf A is more effective in regulating TG level and Mf B is more powerful in modulating TC.level in atherosclerotic rats. 展开更多
关键词 Mallotus furetianus Anti-atherosclerotic leaves extract
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Extraction, purification and antioxidant activity of polysaccharides from bamboo leaves 被引量:12
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作者 GAO Ya-ni · TIAN Cheng-rui · ZHAO Li-li 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第1期139-143,共5页
Ultrasonic extraction (UE) was employed for the extraction of bamboo leaf polysaccharides (BLP). The influential parameters of UE procedure including extraction time, ultrasonic power and solid/liquid ratio were o... Ultrasonic extraction (UE) was employed for the extraction of bamboo leaf polysaccharides (BLP). The influential parameters of UE procedure including extraction time, ultrasonic power and solid/liquid ratio were optimized by orthogonal experiments. DEAE-cellulose col- umn chromatography was applied to purify BLP and then the radical scavenging activity of BLP was also evaluated. Optimal extraction con- ditions were: extraction time .of 15 min, ultrasonic power of 300 W, and solid/liquid ratio of 1:15. Four kinds of polysaccharides were obtained by DEAE-cellulose colunm chromatography; the maximum superoxide radical scavenging rate (20.4%) of BLP was inferior to that of vitamin C (Vc, the control) and the hydroxyl radical scavenging rate (50%) was equivalent to that of Vc. 展开更多
关键词 bamboo leaves POLYSACCHARIDE scavenging radical separa-tion and purification ultrasonic extraction
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Solvent extraction of vanadium from sulfuric acid solution 被引量:11
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作者 WANG Mingyu ZHANG Guiqing WANG Xuewen ZHANG Jialiang 《Rare Metals》 SCIE EI CAS CSCD 2009年第3期209-211,共3页
The behaviour of vanadium(V) extracted from sulfuric acid solution was investigated using Cyanex 923 as an extractant. The effects of the concentration of Cyanex 923 and the pH of the solution were studied. The extr... The behaviour of vanadium(V) extracted from sulfuric acid solution was investigated using Cyanex 923 as an extractant. The effects of the concentration of Cyanex 923 and the pH of the solution were studied. The extraction of vanadium(V) increases with the increase of Cyanex 923 concentration and shaking time. Cyanex 923 can extract vanadium(V) from sulfuric acid solution at low pH conditions, and the best pH conditions for extraction of vanadium(V) are at pH 1.0-2.0. The species extracted into the organic phase is VO2HSO4 with one molecule of Cyanex 923. Equilibrium studies were used to assess the extraction efficiency of vanadium(V) recovery from the sulfuric acid solution. 展开更多
关键词 solvent extraction vanadium(V) Cyanex 923 sulfuric acid solution
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Dengue fever treatment with Carica papaya leaves extracts 被引量:4
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作者 Nisar Ahmad Hina Fazal +3 位作者 Muhammad Ayaz Bilal Haider Abbasi Ijaz Mohammad Lubna Fazal 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第4期330-333,共4页
The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes.For the treatment of Dengue fever the e... The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes.For the treatment of Dengue fever the extract was prepared in water.25 mL of aqueous extract of C.papaya leaves was administered to patient infected with Dengue fever twice daily i.e.morning and evening for five consecutive days.Before the extract administration the blood samples from patient were analyzed.Platelets count(PLT),White Blood Cells(WBC) and Neutrophils(NEUT) decreased from 176×10~3/μ L,8.10×10~3/μ L,84.0%to 55×10~3/μ L,3.7×10~3/μL and 46.0%.Subsequently,the blood samples were rechecked after the administration of leaves extract.It was observed that the PLT count increased from 55×10~3/μ L to 168×10~3/μ L,WBC from 3.7×10~3/μ L to 7.7×10~3/μ L and NEUT from 46.0%to 78.3%.From the patient feelings and blood reports it showed that Carica papaya leaves aqueous extract exhibited potential activity against Dengue fever.Furthermore,the different parts of this valuable specie can be further used as a strong natural candidate against viral diseases. 展开更多
关键词 DENGUE fever CARICA PAPAYA leaves extractS PLATELETS Potential activity
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COSMO-RS prediction and experimental verification of 1,5-pentanediamine extraction from aqueous solution by ionic liquids 被引量:10
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作者 Chenhao Jiang Hongye Cheng +5 位作者 Zexian Qin Ruizhuan Wang Lifang Chen Chen Yang Zhiwen Qi Xiucai Liu 《Green Energy & Environment》 SCIE CSCD 2021年第3期422-431,共10页
1,5-Pentanediamine(PDA)produced by biological fermentation becomes popular,but the separation of PDA from the broth is a typical difficult problem.In this work,the performance of 200 ionic liquids(ILs),formed by combi... 1,5-Pentanediamine(PDA)produced by biological fermentation becomes popular,but the separation of PDA from the broth is a typical difficult problem.In this work,the performance of 200 ionic liquids(ILs),formed by combining 25 cations and 8 anions,in the extraction of PDA from aqueous solution were evaluated using COSMO-RS model.The extraction mechanism was investigated with the help ofσ-profile and interaction energy analyses.Both the cation and anion have impacts on the extraction efficiency,where cation mainly influences the interaction of IL with PDA and anion affects the hydrophobicity of IL.The IL composed of long alkyl-chain in cation and the anion of[PF6]-or[TF2 N]-,which has theσ-profile more likely distributed in the nonpolar region but less distributed in the polar region,is favorable for extraction.The experimental liquid-liquid equilibrium demonstrated the effects of cation and anion on extraction performance,which validated the reliability of COSMO-RS model in IL screening for PDA extraction.The IL[IM-1,8][PF6]could serve as a promising extractant for the downstream separation process of the biological production of PDA. 展开更多
关键词 1 5-Pentanediamine Ionic liquids Aqueous solution extractION COSMO-RS model
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Protective effects of ginkgo biloba leaves extract on peroxide-induced oxidative stress damage in PC12 cells 被引量:3
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作者 Weiqiang Chen Taiping Hu Ying Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第6期369-371,共3页
BACKGROUND: Extracts of ginkgo biloba leaves (EGB) and its metabolites have been reported to enhance brain function and nerve behavior. It has also been hypothesized that they can protect neurons from oxidative str... BACKGROUND: Extracts of ginkgo biloba leaves (EGB) and its metabolites have been reported to enhance brain function and nerve behavior. It has also been hypothesized that they can protect neurons from oxidative stress. OBJECTIVE: To investigate protective effects of EGB on peroxide (H2O2)-induced oxidative stress damage in PC12 cells. DESIGN: Observational contrast study. SETTING: Department ofPathophysiology, Guangdong Pharmacological College. MATERIALS: EGB was provided by Xi'an Fujie Biotechnological Development Company; 1640 culture medium, methylthiazolyl tetrazolium (MTT), trypsin and dimathyl sulfoxide (DMSO) by Sigma Company; PC12 cell strain by Cell Center of Medical College of Zhongshan University; calf serum by Hangzhou Sijiqing Bioengineering Company; lactate dehydrogenase (LDH) kit by Nanjing Jiancheng Bioengineering Research Institute. METHODS: The experiment was carried out in Department of Cell Biology of Guangdong Pharmacological College from June to December 2005. ①Cell culture: PC12 cells were cultured in 1640 medium containing 200 g/L fetal calf serum. The cells were diluted to 1 × 10^7 L^-1 and washed every two days. Those cells were used to experiment until they grew in logarithm on solid wall. ② Grouping and intervention: PC12 cells (1 × 10^8L^-1) were plated in 96-well plates with the density of 200 μ L/hole and divided into three groups: normal control group (routinely adding media), H2O2 group (treating with media and H2O2 for 20 hours) and EGB group (adding media, 100μmol/L EGB and 100 μmol/L H2O2). ③ MTT assay: PC12 cells (1 × 10^8L^-1) were plated in 96-well plates and divided into three groups with 8 holes for each group. Under sterile condition, cells were added with 5 g/L MTT (100μL) and cultured for 4 hours. And then, 200 μ L DMSO fluid was added and shaken for 30 minutes until blue crystal products formed were dissolved soundly ④ Experimental evaluation: Absorbance (A) at 630 nm was measured and LDH activity was measured at the same time. MAIN OUTCOME MEASURES: Results of MTT assay and LDH activity. RESULTS: ① Results of MTT assay: A value was lower in the H2O2 group than that in the normal control group (P 〈 0.01), while A value was higher in the EGB group than that in the H2O2 group (P 〈 0.01). ② LDH activity: LDH activity was higher in the H2O2 group than that in the normal control group (P 〈 0.01 ), while LDH activity was lower in the EGB group than that in the H2O2 group (P 〈 0.01). CONCLUSION: EGB can inhibit H2O2-induced oxidative stress damage in PC12 cells possibly by preventing damage to the cell membrane. 展开更多
关键词 PC12 cell H2O2: extracts of ginkgo biloba leaves
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Study on Gold (Ⅰ) Solvent Extraction from Alkaline Cyanide Solution by TBP with Addition of Surfactant 被引量:2
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作者 潘学军 陈景 《Rare Metals》 SCIE EI CAS CSCD 1999年第2期9-17,共9页
The new solvent extraction system for gold() from alkaline cyanide solution by TBP with addition of surfactant in aqueous phase was studied. The effect of various factors, such as equilibrium pH, constitution of organ... The new solvent extraction system for gold() from alkaline cyanide solution by TBP with addition of surfactant in aqueous phase was studied. The effect of various factors, such as equilibrium pH, constitution of organic phase, molar ratio of CPBAu(CN)2-, extraction time, aqueous/organic phase ratio, different initial gold concentration, equilibrium temperature, different diluent, different types of extractants and surfactants etc., was inspected. The results show that gold() can be extracted quantitatively by controlling the quantity of surfactant (CPB); both the equilibrium pH and diluent hardly influence percent extraction. Gold() percent extraction reaches more than 98% under the optimal experimental conditions. 30% vol TBP diluted by sulphonating kerosene can load gold() to rather high levels. Loading capacity is in excess of 38 g/L. The extraction mechanism is discussed and the overall extraction reaction is deduced. 展开更多
关键词 Solvent extraction Gold() Cyanide solution SURFACTANT
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Effects of ethanol extract of leaves of Helianthus annus on the fecundity of Wistar rats 被引量:1
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作者 Ejebe Daniel Emamuzo Siminialayi Iyeopu Miniakiri +2 位作者 Emudainohwo Joseph Oghenebrorie Tedwin Kagbo Hope Delesi Amadi Precious 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第6期435-438,共4页
Objective:To evaluate the effects of ethanol extract of leaves of Helianthus annus(H.annus) on the fecundity of Wistar rats.Methods:Forty(20 male and 20 female) Wistar rats,grouped into control,ethanol extract treated... Objective:To evaluate the effects of ethanol extract of leaves of Helianthus annus(H.annus) on the fecundity of Wistar rats.Methods:Forty(20 male and 20 female) Wistar rats,grouped into control,ethanol extract treated rats and untreated,were used for the study.Treated rats had 0.5 g/kg of ethanol extract orally for 2 weeks;control rats had 5%alcoholic water(solvent);and untreated rats had their normal feed and clean drinking water.Following treatment,the animals were sub-grouped into 5 mating groups to observe the coital frequency,pregnancy rate and average number of pups per group in pairs.Results:The results showed that coital frequency was unaffected by the extract treatment but pregnancy rate and number of pups per rat and per group were reduced significantly in groupsⅡ,ⅢandⅣcompared to those of groupⅠandⅤrats which were not treated with the ethanol extract of leaves of H.annus.Conclusions:The histodegenerative in the gonads reportedly induced by this ethanol extract in previous studies may be responsible for the reduced fecundity observed in treated adult rats. 展开更多
关键词 ETHANOL extract HELIANTHUS annus leaves FECUNDITY RATS
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Antidiabetic and antidiarrhoeal effects on ethanolic extract of Psidium guajava(L.) Bat.leaves in Wister rats 被引量:1
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作者 Santosh Mazumdar Rashcda Akter Debashish Talukder 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第1期10-14,共5页
Objective:To evaluate the antidiabetic and the antidiarrhoeal effects of ethanolic extracts of Psidium guajava leave(EEPGL) in Wisier rais to support its traditional uses.Methods:Oral glucose tolerance test model and ... Objective:To evaluate the antidiabetic and the antidiarrhoeal effects of ethanolic extracts of Psidium guajava leave(EEPGL) in Wisier rais to support its traditional uses.Methods:Oral glucose tolerance test model and alloxan induced diabetic test model were performed to evaluate antidiabetic activity of EEPGL at doses of 1.00.0.50 and 0.75 g/kg respectively.For antidiarrhoeal effects of EEPGL.castor oil-induced diarrhoea model and gastrointestinal motility test with barium sulphate milk model were also assessed at doses of750.500 and 250 mg/kg.respectively.Results:Administration of EEPGL at doses 1.00 and 0.50 g/kg significantly(P<0.05)decreased blood glucose levels in oral glucose tolerance test model as well as 0.75 g/kg dose in alloxan induced diabetic test model in Wister rats(P<0.001).Application of EEPGL at doses of 750 and 500 mg/kg showed antidiarrhoeal effect in castor oil-induced diarrhoeal model(P<0.00 l and P<0.01,respectively),and 750 mg/kg(P<0.01),500 and 250 mg/kg(P<0.05)doses in barium sulphate milk model in aforesaid animals.Conclusions:These results exhibited the significant antidiabetic and antidiarrhoeal activities of ethanolic extracts of Psidium guajava leave in Wister rats. 展开更多
关键词 PSIDIUM guajava leavE extract ANTIDIABETIC Antidiarrhoea WISTER RATS
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Synergistic Extraction of Gallium from Sulfate Solution 被引量:2
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作者 邓彤 黄丽娟 傅丽 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第1期112-115,共4页
A novel extractant mixture, di-2-ethylhexyl phosphate (DEHPA) plusHX, was proposed and tested for recovering gallium from sulfatesolution. It was found that the extraction capacity of DEPHA forgallium from sulfate sol... A novel extractant mixture, di-2-ethylhexyl phosphate (DEHPA) plusHX, was proposed and tested for recovering gallium from sulfatesolution. It was found that the extraction capacity of DEPHA forgallium from sulfate solution could be enhanced significantly due tothe synergistic effect of acidic extractant HX. Gallium extraction isnegligible below pH 0 and highly sensitive to pH of aqueous phase inthe range from 0 to 1, and satisfactory extraction can be gained atpH>1. More than 96/100 Ga Extraction was obtained using 15/100 DEHPAplus 2/100 HX. 展开更多
关键词 GALLIUM synergistic extraction DEHPA sufate solution
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Enhanced extraction of scandium and inhibiting of iron from acid leaching solution of red mud by D2EHPA and sodium chloride 被引量:3
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作者 LIWang LIU Yue ZHU Xiao-bo 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3029-3039,共11页
D2EHPA(P204),tri-butyl-phosphate(TBP)and sodium chloride(NaCl)were attractive for selective extraction of scandium from acid leaching solution of red mud.The extraction parameters of P204 concentration(X_(P204)),NaCl ... D2EHPA(P204),tri-butyl-phosphate(TBP)and sodium chloride(NaCl)were attractive for selective extraction of scandium from acid leaching solution of red mud.The extraction parameters of P204 concentration(X_(P204)),NaCl concentration(C_(NaCl)),pH value,reaction time,stirring speed and O/A were investigated to extract scandium and separate iron from the acid leaching solution.The extraction mechanism was analyzed by Fourier transform infrared spectroscopy(FT-IR)and thermodynamic theory.The single-stage extraction efficiency of scandium,iron andβ(Sc/Fe)were 99.1%,9.4%and 1061.2,respectively,with C_(NaCl) of 75 g/L and XP204 of 0.75 at solution pH value of 1.2 and stirring speed of 200 r/min for 6 min,in which a good separation effect of scandium and iron was obtained.The vibration absorption peak Sc─O was contributed to the extraction of scandium with P204.The complex[FeCln]^(3−n) existed in the solution with adding NaCl into the acid leaching solution.The value of n was higher and the valence state of the complex[FeCln]^(3−n) was lower with an increase of chloride concentration,which restricts the extraction efficiency of iron with P204.The extraction of three stages in the counter-current simulation experiments was carried out according to the McCabe-Thiele diagram.Gibbs free energy change(ΔG)of−5.93 kJ/mol,enthalpy change(ΔH)of 23.45 kJ/mol and entropy change(ΔH)of 98.54 J/(mol·K)were obtained in the solvent extraction proces,which indicate that the extraction reaction is easily spontaneous and endothermic and a proper increase of temperature is conducive to the extraction of scandium. 展开更多
关键词 SCANDIUM selective extraction D2EHPA/sodium chloride leaching solution red mud
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Study on Extraction Method of Carotenoids from Citrus Leaves 被引量:3
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作者 ZHANG Wei XIE Dan +1 位作者 WEN Zhi-yong ZHONG Guang-yan 《Agricultural Science & Technology》 CAS 2020年第2期26-31,共6页
In order to explore the extraction method of carotenoids from citrus leaves,the extraction effect of carotenoids from leaves of Honey pomelo by ultrasonic-assisted extraction was investigated by single factor experime... In order to explore the extraction method of carotenoids from citrus leaves,the extraction effect of carotenoids from leaves of Honey pomelo by ultrasonic-assisted extraction was investigated by single factor experiment and orthogonal experiment.The results showed that the optimum extraction condition was:the ration of ethanol and acetone 1∶1(v/v,containing 0.1%BHT),solid-liquid ratio 1∶30(g/mL),extraction time 7 min,ultrasonic power 240 W,extraction frequency 3 times.Under the above condition,the extraction rate of carotenoids was 85.98%. 展开更多
关键词 CITRUS leaves Carotenoids extraction methods
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