This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes （white clover and alfalfa） and ...This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes （white clover and alfalfa） and a perennial gramineous grass （tall fescue） were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and diethyl ether and analyzed by high- performance liquid chromatography （HPLC） by comparing to soil tillage. A total of ten phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids （hydroxybenzoic and hydroxycinnamic acids） and flavonoids （flavanols and flavonols）. The concentration of flavonoid compounds （409.43 to 538.63 mg kg^-1 and 56.16 to 81.30 mg L^-1） was higher than nonflavonoids （76.91 to 98.85 mg kg^-1 and 30.65 to 41.22 mg L^-1） for Cabernet Sauvignon grape and wine under different treatments, respectively. In the flavonoid phenolics, Catechin was the most abundant in the different grapes and wines, accounting for 74.94 to 79.70% and 48.60 to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments （tall fescue and white clover） and soil tillage for the content of benzoic acid, salicylic acid, caffeic acid, catechin, and total phenolics in the grape berry （P 〈 0.05 or P〈0.01）. The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments： tall fescue, white clover, alfalfa, and soil tillage （control）. Cover crop in vineyard increased total phenols of grape berry and wine, and thus improved the quality of wine evidently.展开更多
针对实景三维模型在实际使用中需要单体化的问题,提出一种基于实景三维模型的单体化模型重建技术。基于实景三维模型、空三成果、倾斜摄影航片和手持拍摄照片进行三维模型的重建,并进行了实验。结果表明,该方法能够快速完成三维模型重建...针对实景三维模型在实际使用中需要单体化的问题,提出一种基于实景三维模型的单体化模型重建技术。基于实景三维模型、空三成果、倾斜摄影航片和手持拍摄照片进行三维模型的重建,并进行了实验。结果表明,该方法能够快速完成三维模型重建,重建的三维模型有较高的还原度和精度,满足LOD(Levels of Detail,多层次细节)3级别模型的要求。展开更多
This scientific article examines the issue of changes in the density and speed of the airflow in the pipeline pneumatic conveying equipment used in ginneries, analyzes the causes of changes in the density and speed of...This scientific article examines the issue of changes in the density and speed of the airflow in the pipeline pneumatic conveying equipment used in ginneries, analyzes the causes of changes in the density and speed of air.展开更多
There have been many achievements in the research on carbon isotopes of alkane hydrocarbon gases in oil and gas bearing basins in China. Because of the limited molecular types and the simple molecular structures of C&...There have been many achievements in the research on carbon isotopes of alkane hydrocarbon gases in oil and gas bearing basins in China. Because of the limited molecular types and the simple molecular structures of C<sub>1-4</sub> alkane hydrocarbon gases, the information provided by these carbon isotopes is limited. C<sub>5-8</sub> light hydrocarbons are found more often in wet gas, and their molecules have more complex structures and展开更多
HLA-A~*2402 is one of the most frequent HLA-A allele in Asian population.To construct HLA-A~*2402-peptide tetramers,the transmembrane and intracellular segments of HLA-A~*2402 cDNA were replaced with BSP sequence to f...HLA-A~*2402 is one of the most frequent HLA-A allele in Asian population.To construct HLA-A~*2402-peptide tetramers,the transmembrane and intracellular segments of HLA-A~*2402 cDNA were replaced with BSP sequence to form a fusion gene of sHLA-A~*2402-BSP.The sHLA-A~*2402-BSP fusion protein and β2m were high-level expressed as insoluble aggregates in E.coli,and refoided to form an HLA-A~*2402-peptide monomeric complex by dilution method in the presence of an antigenic peptide.The HLA-A~*2402-peptide monomeric complex was biotinated and tetramized to prepare HLA-A~*2402-peptide tetramer.Then using the HLA-A~*2402-peptide tetramers to detect antigen-specific cytotoxic T lymphocyte(CTL)induced by artificial antigen presenting cell (aAPC)in vitro.The results showed that HLA-A~*2402-peptide tetramer was prepared correctly,and functional in detecting antigen-specific CTL in vitro,HLA-A~*2402-peptide monomeric and its multimeric complexes are expected to provide a powerful tool for studying mechanisms of immune-related diseases in Asian populations. Cellular & Molecular Immunology.2005;2(2):145-149.展开更多
Using electrospray ionization tandem mass spectrometry combined with liquid chromatography(LC),a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants(m-PFRs)and three oli...Using electrospray ionization tandem mass spectrometry combined with liquid chromatography(LC),a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants(m-PFRs)and three oligomeric organophosphorus flame retardants(o-PFRs)in fish muscle samples.The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples.The recoveries of analytes in fish muscle samples were in the range of 74-105%.The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6-8.9%.The concentrations of analytes in procedural blanks were below the limit of quantification(LOQ)values.Furthermore,the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste(ewaste)processing area in northern Vietnam.The concentrations of m-PFRs such as tris(2-chloroethyl)phosphate(TCEP),tris(2-chloroisopropyl)phosphate(TCIPP),and triphenyl phosphate(TPHP)were dominant among the investigated m-PFRs.The respective concentrations of TCEP,TCIPP,and TPHP were up to 160,300,and 230 ng g^-1 lipid weight,respectively,whereas those of o-PFRs were up to 10 ng g^-1 lipid weight.The results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.展开更多
Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenol...Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from grape berries using response surface methodology was here achieved. Cabernet Sauvignon (CS) wine grapes (Vitis vinifera L. cv. Cabernet Sauvignon) are a rich source of anti-radical phe- nols, extractable as dietary supplements. However, efficiency of extraction strongly depends on specific experimental conditions. In this work, the comparison between two extraction mixtures, Acetone/Water (A/W) and Methanol/Water (M/W) and the effects of three critical variables—Extraction Time (between 8 and 88 h), Extraction Temperature (between 1?C and 35?C) and Solvent Content (between 63% and 97%)—on Phenolic Compounds Yield (PCY) and Monomeric Anthocyanins Yield (MAY) were studied using Response Surface Methodology (RSM). Process conditions maximizing the PCY were found to be 87% A/W solvent content, after 88 h incubation at 26?C, and those of the MAY were found to be 97% M/W solvent content, after 8 h incubation at 1?C. In addition, chromatographic profiles of extracts showed very different affinities of the phenolic compounds families to the experimental conditions employed. This process advantages are: low percentage of organic solvent used, high quality of extracted molecules thanks to low temperature treatment, very low energy consumption and low cost of needed machinery. At industrial scale, it may be used as promising technique for the extraction of bioactive compounds from plant or byproduct material such as from wine or grape juice industries.展开更多
Abundant carbon isotopic information of single molecule can be obtained from the trace samples (chromatographic grade) on the basis of carbon isotopic on-line analytical technique developed in the late 1980s. This bri...Abundant carbon isotopic information of single molecule can be obtained from the trace samples (chromatographic grade) on the basis of carbon isotopic on-line analytical technique developed in the late 1980s. This brings the carbon isotopic study of the petroleum and natural gases into a new development stage.展开更多
Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic...Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic. But the yield of monomeric B27 Lys destripeptide insulin is limited, because monomeric B27 Lys destripeptide insulin precursor( MIP) was easily to form inclusion body,when MIP is expressed in E. coli. The precursor,MIP,is not only fused to an N-terminal HIS-small ubiquitin-related modifier( SUMO) tag,but also added five Arginine( 5 R) at the C-terminal,which can improve the solubility of the fusion protein. By this way,the yield of fusion protein has been up to 1. 45 mg/L cell culture.This work set up the foundation for the clinical application of B27 Lys destripeptide insulin.展开更多
AIM: To establish a method to simultaneously determine the main five alkaloids of Catharanthus roseus for trace samples, a high-performance liquid chromatography–electrospray ionization-tandem mass spectrometry(HPLC-...AIM: To establish a method to simultaneously determine the main five alkaloids of Catharanthus roseus for trace samples, a high-performance liquid chromatography–electrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS) analysis method was developed. METHOD: The five Catharanthus alkaloids, vinblastine, vincristine, vinleurosine, vindoline, and catharanthine were chromatographically separated on a C18 HPLC column. The mobile phase was methanol-15 nmol?L–1 ammonium acetate containing 0.02% formic acid(65 : 35, V/V). The quantification of these alkaloids was based on the Multiple Reaction Monitoring(MRM) mode. RESULTS: This method was validated, and the results achieved the aims of the study. The intra- and inter-day precision and accuracy of the five alkaloids were within 1.2%-11.5%(RSD%) and-10.9%-10.5%(RE%). The recovery rates of the five alkaloids of samples were from 79.9% to 91.5%. The five analytes were stable at room temperature for 2 h, at 4 °C for 12 h, and at-20 °C for two weeks. The developed method was applied successfully to determine the content of the five alkaloids in three plant parts of three batches of C. roseus with a minute amount collected from three regions of China. CONCLUSION: The HPLC-ESI-MS/MS method can be used for the simultaneous determination of five important alkaloids in trace C. roseus samples.展开更多
In this work, optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from Syrah (Sy) wine grapes (Vitis vinifera L. cv. Syrah) using response surface methodology was conducted. The comparis...In this work, optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from Syrah (Sy) wine grapes (Vitis vinifera L. cv. Syrah) using response surface methodology was conducted. The comparisons between two extraction mixtures, Acetone/Water (A/W) as well as Methanol/Water (M/W) and the effects of three critical variables, Extraction Time (between 8 and 88 h), Extraction Temperature (between 1℃ and 35℃) and Solvent Content (between 63% and 97%), on Phenolic Compounds Yield (PCY), Monomeric Anthocyanins Yield (MAY) and the DPPH Free Radical Inhibition Potential (DFRIP) were studied. The highest PCY was obtained in 63% A/W solvent content after 88 h incubation at 35℃. The highest MAY was acquired in 97% M/W solvent content after 8 h incubation at 17℃. The highest DFRIP of the extract was attained using 97% A/W solvent content after 16 h incubation at 35℃. The low cost of this process, on economic and environmental levels, could lead to interesting applications on an industrial scale. It could be used to obtain bioactive phytochemicals from direct material or byproducts for either therapeutic or nutritional purposes.展开更多
A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperatur...A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperature combinations. Most purple tea consumers usually brew the tea leaves then add some lemon juice before consuming it. Citric acid was used here to mimic the use of lemon juice. Documentation on the quality of such a brew is scanty and the effect of acid on its quality is equally scanty. The current study used brewing time/temperature combinations of 5, 10 and 15 minutes with 70°C and 92°C drinking water. Total monomeric anthocyanins were analysed using UV-1800 spectrophotometer (Shimadzu, Japan) while DDPH method was used to assay for antioxidant activity. Citric acid concentration of 0, 0.1% to 0.5% was used to check their effect on the brews with the highest total anthocyanins and antioxidant activity. The results showed that brewing temperature of 70°C had 9.5 mg/L to 27.7 mg/L, with 5 minutes brewing time being the highest. Temperature of 92°C had 37.5 mg/L to 92 mg/L with 5 minutes brewing time having the highest total monomeric anthocyanins. Antioxidant activity of 92°C brewing temperature ranged from 90.7% to 92.0%. Total monomeric anthocyanins increased with increased citric acid concentration up to 0.3% before it decreases while for antioxidant activity, it decreased with addition of citric acid. It was concluded that for maximum anthocyanins extraction, 5 minutes brewing time is the best while ten minutes brewing time could give optimum antioxidant activity.展开更多
Blood glucose lowering assay proved that [B16Ala]insulin and [B26Ala]insulin exhibit potency of acute blood glucose lowering in normal pigs, which demonstrates that they are fast- acting insulin. Single-chain precurso...Blood glucose lowering assay proved that [B16Ala]insulin and [B26Ala]insulin exhibit potency of acute blood glucose lowering in normal pigs, which demonstrates that they are fast- acting insulin. Single-chain precursor of [B16Ala]insulin and [B26Ala]insulin is [B16Ala]PIP and [B26Ala]PIP, respectively, which are suitable for gene expression. Secretory expression level of the precursors in methylotrophic yeast Pichia pastoris was quite high, 650 mg/L and 130 mg/L, respectively. In vivo biological assay showed that the two fast-acting insulins have full or nearly full biological activity. So both [B16Ala]insulin and [B26Ala]insulin can be well developed as fast-acting insulin for clinic use.展开更多
The coordination number of the gadolinium atom and bond distances in the crystal of inonomeric porphyrinate,[Gd(TPP)acac-8H2O 3TCB] (TCB: 1,2,4-trichlorobenzene,acac: anion of acetylacetone),were determined by EXAFS ... The coordination number of the gadolinium atom and bond distances in the crystal of inonomeric porphyrinate,[Gd(TPP)acac-8H2O 3TCB] (TCB: 1,2,4-trichlorobenzene,acac: anion of acetylacetone),were determined by EXAFS method.The Gd atom is eight-coordinated to the four nitrogen atoms of a tetraphenylporphyrin ring,to the two oxygen atoms of one acetylacetonato anion and to two water molecules with Gd-N=0.232 nm,Gd-O=0.243 nm.展开更多
(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvat...(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonal bipyramidal coordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex.展开更多
The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte memb...The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte membranes are obtained.Weaker power laser irradiation can delay the decay of the mechanical properties of erythrocytes and promote the biological activity of erythrocytes,while higher power laser irradiation damages erythrocytes.The stronger the laser irradiation is,the more obvious and rapid the damage will be.The temperature of the cell surface will be changed by regulating the laser power and irradiation time,so the biological functions of erythrocyte can be controlled.Secondly,the finite element simulation of the temperature change on the cell surface under the condition of laser irradiation is carried out using simulation software,and the precise temperature of the cell surface irradiated cumulatively by a laser with different powers is obtained.Finally,the processes of abscission,unfolding,and denaturation of hemoglobins in erythrocytes at different temperatures due to the photothermal effect are analyzed using the model.The mechanism of laser irradiation on the elasticity of erythrocyte membranes is also obtained.展开更多
The solid waste generated in industrial berry juice production was considered as a low cost raw material for the extraction of natural antioxidants. Berries contain phenolic compounds with high antioxidant potential, ...The solid waste generated in industrial berry juice production was considered as a low cost raw material for the extraction of natural antioxidants. Berries contain phenolic compounds with high antioxidant potential, including anthocianin. Quantitative determination method for monomeric anthocianins in bilberry juice and marc was validated. An official method from Association of Analytical Communities was used to determine anthocianins in juice and marc extracts by measuring light absorption for solutions with pH values 1.0 and 4.5 at 520 nm and 700 rim. Results were expressed as cyanidin-3-glucoside equivalent, as it is the most common anthocianin pigment. Calibration curve was obtained, linearity was checked, working interval and accuracy was determined and samples were tested. Mentioned method was evaluated as appropriate for quantitative anthocianin analysis in bilberry juice and marc. Necessity of calibration curve was approved using extinction coefficient of cyanidin-3-glucoside instead. Method assures adequate precision and accuracy as well.展开更多
基金supported by "13115" Science and Tech-nology Innovation Programme of Shaanxi Province,China (2007ZDKG-09)the National Agricultural Industrial Technology System Foundation of China(Z225020901)Young Academic Backbone Scientific Research Program of Northwest A&F University,China (01140303)
文摘This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes （white clover and alfalfa） and a perennial gramineous grass （tall fescue） were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and diethyl ether and analyzed by high- performance liquid chromatography （HPLC） by comparing to soil tillage. A total of ten phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids （hydroxybenzoic and hydroxycinnamic acids） and flavonoids （flavanols and flavonols）. The concentration of flavonoid compounds （409.43 to 538.63 mg kg^-1 and 56.16 to 81.30 mg L^-1） was higher than nonflavonoids （76.91 to 98.85 mg kg^-1 and 30.65 to 41.22 mg L^-1） for Cabernet Sauvignon grape and wine under different treatments, respectively. In the flavonoid phenolics, Catechin was the most abundant in the different grapes and wines, accounting for 74.94 to 79.70% and 48.60 to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments （tall fescue and white clover） and soil tillage for the content of benzoic acid, salicylic acid, caffeic acid, catechin, and total phenolics in the grape berry （P 〈 0.05 or P〈0.01）. The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments： tall fescue, white clover, alfalfa, and soil tillage （control）. Cover crop in vineyard increased total phenols of grape berry and wine, and thus improved the quality of wine evidently.
文摘针对实景三维模型在实际使用中需要单体化的问题,提出一种基于实景三维模型的单体化模型重建技术。基于实景三维模型、空三成果、倾斜摄影航片和手持拍摄照片进行三维模型的重建,并进行了实验。结果表明,该方法能够快速完成三维模型重建,重建的三维模型有较高的还原度和精度,满足LOD(Levels of Detail,多层次细节)3级别模型的要求。
文摘This scientific article examines the issue of changes in the density and speed of the airflow in the pipeline pneumatic conveying equipment used in ginneries, analyzes the causes of changes in the density and speed of air.
文摘There have been many achievements in the research on carbon isotopes of alkane hydrocarbon gases in oil and gas bearing basins in China. Because of the limited molecular types and the simple molecular structures of C<sub>1-4</sub> alkane hydrocarbon gases, the information provided by these carbon isotopes is limited. C<sub>5-8</sub> light hydrocarbons are found more often in wet gas, and their molecules have more complex structures and
基金This study was supported by National Key Basic Research Program of China(No.CB 510008)National Natural Science Foundation of China(No.30271201).
文摘HLA-A~*2402 is one of the most frequent HLA-A allele in Asian population.To construct HLA-A~*2402-peptide tetramers,the transmembrane and intracellular segments of HLA-A~*2402 cDNA were replaced with BSP sequence to form a fusion gene of sHLA-A~*2402-BSP.The sHLA-A~*2402-BSP fusion protein and β2m were high-level expressed as insoluble aggregates in E.coli,and refoided to form an HLA-A~*2402-peptide monomeric complex by dilution method in the presence of an antigenic peptide.The HLA-A~*2402-peptide monomeric complex was biotinated and tetramized to prepare HLA-A~*2402-peptide tetramer.Then using the HLA-A~*2402-peptide tetramers to detect antigen-specific cytotoxic T lymphocyte(CTL)induced by artificial antigen presenting cell (aAPC)in vitro.The results showed that HLA-A~*2402-peptide tetramer was prepared correctly,and functional in detecting antigen-specific CTL in vitro,HLA-A~*2402-peptide monomeric and its multimeric complexes are expected to provide a powerful tool for studying mechanisms of immune-related diseases in Asian populations. Cellular & Molecular Immunology.2005;2(2):145-149.
基金supported by the Ministry of Education,Culture,Sports,Science and Technology,Japan(MEXT)to a project on Joint Usage/Research Center e Leading Academia in Marine and Environmental Research(LaMer),Ehime University.
文摘Using electrospray ionization tandem mass spectrometry combined with liquid chromatography(LC),a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants(m-PFRs)and three oligomeric organophosphorus flame retardants(o-PFRs)in fish muscle samples.The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples.The recoveries of analytes in fish muscle samples were in the range of 74-105%.The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6-8.9%.The concentrations of analytes in procedural blanks were below the limit of quantification(LOQ)values.Furthermore,the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste(ewaste)processing area in northern Vietnam.The concentrations of m-PFRs such as tris(2-chloroethyl)phosphate(TCEP),tris(2-chloroisopropyl)phosphate(TCIPP),and triphenyl phosphate(TPHP)were dominant among the investigated m-PFRs.The respective concentrations of TCEP,TCIPP,and TPHP were up to 160,300,and 230 ng g^-1 lipid weight,respectively,whereas those of o-PFRs were up to 10 ng g^-1 lipid weight.The results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.
文摘Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from grape berries using response surface methodology was here achieved. Cabernet Sauvignon (CS) wine grapes (Vitis vinifera L. cv. Cabernet Sauvignon) are a rich source of anti-radical phe- nols, extractable as dietary supplements. However, efficiency of extraction strongly depends on specific experimental conditions. In this work, the comparison between two extraction mixtures, Acetone/Water (A/W) and Methanol/Water (M/W) and the effects of three critical variables—Extraction Time (between 8 and 88 h), Extraction Temperature (between 1?C and 35?C) and Solvent Content (between 63% and 97%)—on Phenolic Compounds Yield (PCY) and Monomeric Anthocyanins Yield (MAY) were studied using Response Surface Methodology (RSM). Process conditions maximizing the PCY were found to be 87% A/W solvent content, after 88 h incubation at 26?C, and those of the MAY were found to be 97% M/W solvent content, after 8 h incubation at 1?C. In addition, chromatographic profiles of extracts showed very different affinities of the phenolic compounds families to the experimental conditions employed. This process advantages are: low percentage of organic solvent used, high quality of extracted molecules thanks to low temperature treatment, very low energy consumption and low cost of needed machinery. At industrial scale, it may be used as promising technique for the extraction of bioactive compounds from plant or byproduct material such as from wine or grape juice industries.
文摘Abundant carbon isotopic information of single molecule can be obtained from the trace samples (chromatographic grade) on the basis of carbon isotopic on-line analytical technique developed in the late 1980s. This brings the carbon isotopic study of the petroleum and natural gases into a new development stage.
基金China Postdoctoral Science Foundation Projects(No.2015M571455)National Undergraduate Training Program for Innovation and Entrepreneurship,China(No.17T10509)
文摘Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic. But the yield of monomeric B27 Lys destripeptide insulin is limited, because monomeric B27 Lys destripeptide insulin precursor( MIP) was easily to form inclusion body,when MIP is expressed in E. coli. The precursor,MIP,is not only fused to an N-terminal HIS-small ubiquitin-related modifier( SUMO) tag,but also added five Arginine( 5 R) at the C-terminal,which can improve the solubility of the fusion protein. By this way,the yield of fusion protein has been up to 1. 45 mg/L cell culture.This work set up the foundation for the clinical application of B27 Lys destripeptide insulin.
基金supported by the Fundamental Research Funds for the Central Universities(No.DL09BA21)Special Fund for Forestry Scientific Research in the Public Interest(No.201204601)
文摘AIM: To establish a method to simultaneously determine the main five alkaloids of Catharanthus roseus for trace samples, a high-performance liquid chromatography–electrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS) analysis method was developed. METHOD: The five Catharanthus alkaloids, vinblastine, vincristine, vinleurosine, vindoline, and catharanthine were chromatographically separated on a C18 HPLC column. The mobile phase was methanol-15 nmol?L–1 ammonium acetate containing 0.02% formic acid(65 : 35, V/V). The quantification of these alkaloids was based on the Multiple Reaction Monitoring(MRM) mode. RESULTS: This method was validated, and the results achieved the aims of the study. The intra- and inter-day precision and accuracy of the five alkaloids were within 1.2%-11.5%(RSD%) and-10.9%-10.5%(RE%). The recovery rates of the five alkaloids of samples were from 79.9% to 91.5%. The five analytes were stable at room temperature for 2 h, at 4 °C for 12 h, and at-20 °C for two weeks. The developed method was applied successfully to determine the content of the five alkaloids in three plant parts of three batches of C. roseus with a minute amount collected from three regions of China. CONCLUSION: The HPLC-ESI-MS/MS method can be used for the simultaneous determination of five important alkaloids in trace C. roseus samples.
文摘In this work, optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from Syrah (Sy) wine grapes (Vitis vinifera L. cv. Syrah) using response surface methodology was conducted. The comparisons between two extraction mixtures, Acetone/Water (A/W) as well as Methanol/Water (M/W) and the effects of three critical variables, Extraction Time (between 8 and 88 h), Extraction Temperature (between 1℃ and 35℃) and Solvent Content (between 63% and 97%), on Phenolic Compounds Yield (PCY), Monomeric Anthocyanins Yield (MAY) and the DPPH Free Radical Inhibition Potential (DFRIP) were studied. The highest PCY was obtained in 63% A/W solvent content after 88 h incubation at 35℃. The highest MAY was acquired in 97% M/W solvent content after 8 h incubation at 17℃. The highest DFRIP of the extract was attained using 97% A/W solvent content after 16 h incubation at 35℃. The low cost of this process, on economic and environmental levels, could lead to interesting applications on an industrial scale. It could be used to obtain bioactive phytochemicals from direct material or byproducts for either therapeutic or nutritional purposes.
文摘A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperature combinations. Most purple tea consumers usually brew the tea leaves then add some lemon juice before consuming it. Citric acid was used here to mimic the use of lemon juice. Documentation on the quality of such a brew is scanty and the effect of acid on its quality is equally scanty. The current study used brewing time/temperature combinations of 5, 10 and 15 minutes with 70°C and 92°C drinking water. Total monomeric anthocyanins were analysed using UV-1800 spectrophotometer (Shimadzu, Japan) while DDPH method was used to assay for antioxidant activity. Citric acid concentration of 0, 0.1% to 0.5% was used to check their effect on the brews with the highest total anthocyanins and antioxidant activity. The results showed that brewing temperature of 70°C had 9.5 mg/L to 27.7 mg/L, with 5 minutes brewing time being the highest. Temperature of 92°C had 37.5 mg/L to 92 mg/L with 5 minutes brewing time having the highest total monomeric anthocyanins. Antioxidant activity of 92°C brewing temperature ranged from 90.7% to 92.0%. Total monomeric anthocyanins increased with increased citric acid concentration up to 0.3% before it decreases while for antioxidant activity, it decreased with addition of citric acid. It was concluded that for maximum anthocyanins extraction, 5 minutes brewing time is the best while ten minutes brewing time could give optimum antioxidant activity.
文摘Blood glucose lowering assay proved that [B16Ala]insulin and [B26Ala]insulin exhibit potency of acute blood glucose lowering in normal pigs, which demonstrates that they are fast- acting insulin. Single-chain precursor of [B16Ala]insulin and [B26Ala]insulin is [B16Ala]PIP and [B26Ala]PIP, respectively, which are suitable for gene expression. Secretory expression level of the precursors in methylotrophic yeast Pichia pastoris was quite high, 650 mg/L and 130 mg/L, respectively. In vivo biological assay showed that the two fast-acting insulins have full or nearly full biological activity. So both [B16Ala]insulin and [B26Ala]insulin can be well developed as fast-acting insulin for clinic use.
基金Project supported by the National Natural Science Foundation of China (No. 29701002)the Sate Educational Committee of ChinaShandong University of China
文摘 The coordination number of the gadolinium atom and bond distances in the crystal of inonomeric porphyrinate,[Gd(TPP)acac-8H2O 3TCB] (TCB: 1,2,4-trichlorobenzene,acac: anion of acetylacetone),were determined by EXAFS method.The Gd atom is eight-coordinated to the four nitrogen atoms of a tetraphenylporphyrin ring,to the two oxygen atoms of one acetylacetonato anion and to two water molecules with Gd-N=0.232 nm,Gd-O=0.243 nm.
文摘(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonal bipyramidal coordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex.
基金supported by the National Natural Science Foundation of China (No.61575087)the Natural Science Foundation of Jiangsu Province (No.BK20151164)+2 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No.16KJB140005)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)Jiangsu Collaborative Innovation Center of Advanced Laser Technology and Emerging Industry for the generous financial support
文摘The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte membranes are obtained.Weaker power laser irradiation can delay the decay of the mechanical properties of erythrocytes and promote the biological activity of erythrocytes,while higher power laser irradiation damages erythrocytes.The stronger the laser irradiation is,the more obvious and rapid the damage will be.The temperature of the cell surface will be changed by regulating the laser power and irradiation time,so the biological functions of erythrocyte can be controlled.Secondly,the finite element simulation of the temperature change on the cell surface under the condition of laser irradiation is carried out using simulation software,and the precise temperature of the cell surface irradiated cumulatively by a laser with different powers is obtained.Finally,the processes of abscission,unfolding,and denaturation of hemoglobins in erythrocytes at different temperatures due to the photothermal effect are analyzed using the model.The mechanism of laser irradiation on the elasticity of erythrocyte membranes is also obtained.
文摘The solid waste generated in industrial berry juice production was considered as a low cost raw material for the extraction of natural antioxidants. Berries contain phenolic compounds with high antioxidant potential, including anthocianin. Quantitative determination method for monomeric anthocianins in bilberry juice and marc was validated. An official method from Association of Analytical Communities was used to determine anthocianins in juice and marc extracts by measuring light absorption for solutions with pH values 1.0 and 4.5 at 520 nm and 700 rim. Results were expressed as cyanidin-3-glucoside equivalent, as it is the most common anthocianin pigment. Calibration curve was obtained, linearity was checked, working interval and accuracy was determined and samples were tested. Mentioned method was evaluated as appropriate for quantitative anthocianin analysis in bilberry juice and marc. Necessity of calibration curve was approved using extinction coefficient of cyanidin-3-glucoside instead. Method assures adequate precision and accuracy as well.
