Investigation on catalytic distillation for ethyl acetate production with different catalytic packing structures

The catalytic packing is the core component of the catalytic distillation,and how the catalyst exists in the packing has significant influence on the process.To investigate the effect of catalyst packings on the catalytic distillation process,the classical ethyl acetate reactive distillation system was utilized,and a supported catalytic packing(SCP)was prepared in comparison with the conventional tea-bag catalytic packing(TBP).Laboratory scale experiments showed that the ethyl acetate conversion of the SCP was superior to the TBP at a low catalyst loading.The effects of reaction kinetics,mass transfer performance and actual catalytic efficiency of the packings on this process were regarded as reasons and studied by combining the experiments and numerical simulation.Results suggested that the relatively immediate“in-situ separation”caused by the rapid reaction kinetics and better mass transfer performance of SCP may be a main reason for the difference of the conversion.

Formation mechanisms of ethyl acetate and organic acids in Kluyveromyces marxianus L1-1 in Chinese acid rice soup

This study aims to explore the formation mechanism of ethyl acetate and organic acids in acid rice soup(rice-acid soup)inoculated with Kluyveromyces marxianus L1-1 through the complementary analysis of transcriptome and proteome.The quantity of K.marxianus L1-1 varied significantly in the fermentation process of rice-acid soup and the first and third days were the two key turning points in the growth phase of K.marxianus L1-1.Importantly,the concentrations of ethyl acetate,ethanol,acetic acid,and L-lactic acid increased from day 1 to day 3.At least 4231 genes and 2937 proteins were identified and 610 differentially expressed proteins were annotated to 30 Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways based on the analysis results of transcriptome and proteome.The key genes and proteins including up-regulated alcohol dehydrogenase family,alcohol O-acetyltransferase,acetyl-CoA C-acetyltransferase,acyl-coenzyme A thioester hydrolase,and down-regulated aldehyde dehydrogenase family were involved in glycolysis/gluconeogenesis pathways,starch and sucrose metabolism pathways,amino sugar and nucleotide sugar metabolism pathways,tricarboxylic acid(TCA)cycle,and pyruvate metabolism pathways,thus promoting the formation of ethyl acetate,organic acids,alcohols,and other esters.Our results revealed the formation mechanisms of ethyl acetate and organic acids in rice-acid soup inoculated with K.marxianus L1-1.

Catalytic ozonation of volatile organic compounds(ethyl acetate)at normal temperature

Catalytic treatments of VOCs at normal temperature can greatly reduce the cost and temperature of processing,and improve the safety factor in line with the requirements of green chemistry.Activated carbon fiber(ACF)was pretreated with 10%H_(2)SO_(4)by single factor optimization to increase specific surface area and pore volume obviously.The catalytic ozonation performance of ACF loaded with Au,Ag,Pt and Pd noble metals on ethyl acetate was investigated and Pd/ACF was selected as the optimal catalyst which had certain stability.Pd is uniformly distributed on the surface of ACF,and Palladium mainly exists in the form of Pd0 with a amount of Pd+2.The specific surface area of the catalysts gradually decreases as the loading increases.The activation energy of ethyl acetate calculated by Arrhenius equation is 113 kJ mol 1.With 1%Pd loading and the concentration ratio of ozone to ethyl acetate is 3:1,catalytic ozonation performance is maximized and the conversion rate of ethyl acetate reached to 60%in 3050℃Cat 15,00030,000 h^1.

Efficient Extraction and Isolation of Mangiferin from Mango Leaves by Ethyl Acetate Impurity Removal Method

[Objectives] To optimize the ethyl acetate impurity removal method for extracting and isolating mangiferin from mango leaves,and provide raw materials and technical support for development and use of mangiferin related products. [Methods]Five steps( material crushing→ ethyl acetate impurity removing → concentrated extract washing → extracting with methanol → crystallization and precipitation) were used.The single factor experiment and L9( 34) orthogonal experiment was carried out to optimize the process parameters including extraction time,ultrasonic power,extraction times,and extraction temperature.[Results] The optimum process of ethyl acetate impurity removal method for extracting and isolating mangiferin from mango leaves was as follows: the mango leaves were crushed and sieved; 3 m L/g of ethyl acetate was added,sealed and soaked for 4 h,ultrasonically shaken for 20 min( 50℃,350 W),filtered at room temperature,filtered with 100 mesh sieve,and extracted three times; added 100% methanol to the residue at 3 m L/g,extract by ultrasonic vibration for 20 min( 350 W,55℃)for four times,filtered with 100 mesh sieve when it was still hot; mixed the extract of each time,condensed by vacuum decompression to get the extract; added 100% methanol at 4 m L/g,mixed and washed for 5 min at room temperature,placed for 10 min,filtered with 100 mesh sieve,washed 3 times repeatedly,and dried the filter residue at 60℃ to obtain the crude mangiferin; added 100% methanol at 4 m L/g,mixed and washed at 50℃ for 5 min,placed at 6℃ for 8 h,dried the filter residue at 60℃,and repeatedly crystallized two times. According to the above process,crude and pure mangiferin products could be obtained,the purity of mangiferin of the crude product was higher than 64. 00%,the total recovery rate was 83. 90%,and the purity of mangiferin of the pure product was higher than 98. 00%,and the total recovery rate was about 66. 40%. [Conclusions] The optimized ethyl acetate impurity removal method is easy in operation,low in cost,and high in efficiency for extracting and isolating mangiferin,and can be applied for actual production of mangiferin.

Ethyl acetate extract of Smilax glabra Roxb roots and its major active compound astilbin promote osteoblastogenesis in vitro by upregulating bone cell differentiation-associated genes

Objective:To investigate the osteoblastogenic activity of the ethyl acetate(EtOAc)extract of Smilax glabra Roxb roots and its major active compound astilbin.Methods:Astilbin was isolated from EtOAc extract using silica gel chromatography combined with fraction crystallization.Chemical structure of astilbin was determined by analysis of the spectroscopic data in comparison with the literature.MTT method was used to detect the toxicity.Alkaline phosphatase(ALP)activity was determined by the spectrophotometric method at 405 nm using p-nitrophenyl phosphate as a substrate.Calcium deposition was stained with alizarin red-S,distained with cetylpyridium chloride,and quantified at 562 nm.In silico model for astilbin-ALP interaction was analyzed using AutoDock 4.2.6.The changes in expression of osteoblast differentiation related genes were determined using quantitative real-time PCR.Results:Both the EtOAc extract and astilbin had no toxicity toward osteoblast MC3T3-E1 cells at 5.0,10,25,and 50μg/mL.At 25μg/mL,they enhanced ALP activity and mineralization of osteoblasts up to 30%and 55%for the EtOAc extract and 22%and 41%for astilbin,respectively.Molecular docking analysis of astilbin-ALP interaction revealed Arg167,Asp320,His324,and His437 were key residues participating in hydrophobic interaction;meanwhile,His434 and Thr436 residues were involved in hydrogen bond formation in the active site of human tissue-nonspecific ALP.Moreover,the expression level of genes opn,col1,osx,and runx2 were up-regulated in astilbin treated samples with the fold changes as 2.2;3.7;4.1;2.3,respectively at 10μg/mL(P<0.05).Conclusions:The EtOAc extract and its major compound astilbin exhibit osteoblastogenic activity by up-regulating important markers for bone cell differentiation.It could be a new and promising osteogenic agent with dual actions for therapeutic applications.

Supported catalytic packing prepared from ceramic packing for reactive distillation of ethyl acetate

In this work,a strategy of"etching-modification filling-graft copolymerization"was proposed to load the acidic ionic polyionic liquid on the smooth ceramic surface.In this way,commercial ceramic Raschig rings were successfully transformed into the supported catalytic packing for the reactive distillation,and were further evaluated with esterification reaction of ethyl acetate by means of the fully mixed reactor,the ultrasonic destruction,the cyclic catalysis reaction and the lab-scale distillation column experiment.This catalyst coating has good adhesion with the substrate.It can withstand 24 h of ultrasound damage and shows good stability in three cycle catalytic experiments.This kind of coated catalyst has better catalytic activity than the commercial Amberlyst 15 dry.In the lab-scale reaction distillation,the supported catalyst Raschig ring can achieve a higher conversion in comparison with the tea bag catalytic packing of Amberlyst 15 dry under some conditions.

Effects of Ethyl Acetate Extract of Phyllanthus reticulatus Leaves on Autophagy-related Proteins Beclin-1,ATG5 and LC3 in Nude Mice Xenograft Model of HCC

[Objectives]To explore the effects of ethyl acetate extract of Phyllanthus reticulatus leaves on autophagy-related proteins Beclin-1,ATG5 and LC3 by immunohistochemistry,and to preliminarily explore their effects on autophagy.[Methods]BEL-7404 Hepatocellular Carcinoma(HCC)nude mice model was established,and blank group(same volume of pure water),positive control group(20 mg/kg fluorouracil),high dose drug group(600 mg/kg),and medium dose drug group(300 mg/kg),and low dose drug group(150 mg/kg)were set up.After 2 weeks of intragastric administration,the nude mice were sacrificed,and the tumor tissues were taken out,processed by immunohistochemistry,and then made into paraffin sections.Photos were taken under an optical microscope(10×40),and evaluation and analysis were performed with the aid of the Image-Pro Plus 6.0 image analysis software.Differences were calculated using SPSS 20.0 software.The effects of drugs on autophagy-related proteins LC3,Beclin-1 and ATG5 were observed.[Results]Compared with the blank group,the medium and high dose groups of ethyl acetate extract of P.reticulatus leaves had the effect of promoting the increase of autophagy-related proteins LC3,Beclin-1 and ATG5(P<0.05).However,there was no significant difference between the low dose group of ethyl acetate extract of P.reticulatus leaves and the blank group(P>0.05).[Conclusions]The ethyl acetate extract of P.reticulatus leaves has a promoting effect on autophagy-related proteins LC3,Beclin-1,and ATG5.

Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish

Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products.

Effect of CuO species and oxygen vacancies over CuO/CeO_(2)catalysts on low-temperature oxidation of ethyl acetate

The catalytic oxidation of ethyl acetate(EA)was studied over CuO/CeO_(2) catalysts which were prepared by ball milling with different precursors(copper oxide,cerium acetate,cerium dioxide,copper acetate and cerium hydroxide).The CuO/CeO_(2) catalyst(O-A)prepared with copper oxide and cerium acetate as precursors shows very high catalytic activity that 100%EA conversion is achieved at low temperature of 220℃.It is found that specific surface area(112.8 m^(2)/g),particle size of CuO(3.5 nm)and proportion of oxygen vacancies are prominent on the O-A catalyst.Oxygen vacancies in CeO_(2)support are beneficial to enhancing the adsorption and activation of the oxygen.More finely dispersed CuO particles and oxygen vacancies which are derived from the synergistic interaction of Cu-Ce species play an important role in the catalytic oxidation of EA.

Preventive Effect and Mechanism of Ethyl Acetate Extract of Sceptridium ternatum in Monocrotaline-Induced Pulmonary Arterial Hypertension

Objective:To observe the effect and molecular mechanism of ethyl acetate extract of Sceptridium ternatum(STE)on the monocrotaline(MCT)-induced pulmonary arterial hypertension(PAH).Methods:The main chemical components of Sceptridium ternatum were determined,and the effects in PAH rats were observed.A total of 140 Sprague Dawley rats were randomly and equally divided into the normal group,the model group,the Bosentan group,and the STE groups(2.5,5,10 g/kg)by the random number table method.The characteristic indicators of PAH were measured,and immunohistochemistry was used to observe the lung tissue of rats.Morphological changes of the lung tissue were observed under the light microscope.Results:Compared with the normal group,rats in the model group showed a significant increase in right ventricular free wall thickness(RVFWT),mean pulmonary arterial pressure(mPAP),mean right ventricular pressure(mRVP),max right ventricular pressure(max RVP),weight of right ventricle(RV),and lung index(LI),while a significant decrease in pulmonary artery acceleration time(PAAT,P<0.01).Compared with the model group,rats treated with STE had a significant decrease of RVFWT,mPAP,mRVP,max RVP,and RV,while a significant increase of PAAT(P<0.01).After injection of MCT,nuclear factor-κB(NF-κB)p65 andα-smooth muscle actin(α-SMA)expression levels were up-regulated,and on the contrary,the treatment groups showed a significant downregulation without dose-dependent trend.Conclusions:STE can relieve the PAH in rats.STE may relieve pulmonary vascular disease and pulmonary injury by down-regulating the expression of NF-κB p65 andα-SMA.

Investigation of suitable precursors for manganese oxide catalysts in ethyl acetate oxidation

The control of ethyl acetate emissions from fermentation and extraction processes in the pharmaceutical industry is of great importance to the environment.We have developed three Mn_(2)O_(3)catalysts by using different Mn precursors(MnCl_(2),Mn(CH_(3)COO)_(2),MnSO_(4)),named as Mn_(2)O_(3)-Cl,-Ac,-SO_(4).The tested catalytic activity results showed a sequence with Mn precursors as:Mn_(2)O_(3)-Cl>Mn_(2)O_(3)-Ac>Mn_(2)O_(3)-SO_(4).The Mn_(2)O_(3)-Cl catalyst reached a complete ethyl acetate conversion at 212℃(75℃lower than that of Mn_(2)O_(3)-SO_(4)),and this high activity 100%could be maintained high at 212℃for at least 100 hr.The characterization data about the physical properties of catalysts did not show an obvious correlation between the structure and morphology of Mn_(2)O_(3)catalysts and catalytic performance,neither was the surface area the determining factor for catalytic activity in the ethyl acetate oxidation.Here we firstly found there is a close linear relationship between the catalytic activity and the amount of lattice oxygen species in the ethyl acetate oxidation,indicating that lattice oxygen species were essential for excellent catalytic activity.Through H_(2)temperature-programmed reduction(H_(2)-TPR)results,we found that the lowest initial reduction temperature over the Mn_(2)O_(3)-Cl had stronger oxygen mobility,thus more oxygen species participated in the oxidation reaction,resulting in the highest catalytic performance.With convenient preparation,high efficiency,and stability,Mn_(2)O_(3)prepared with MnCl_(2)will be a promising catalyst for removing ethyl acetate in practical application.

Catalytic oxidation of ethyl acetate on Ce-Mn-O catalysts modified by La

La/Ce_(0.5)Mn_(0.5) catalysts prepared by wetness impregnation of Ce_(_(0.5))Mn_(_(0.5)) with La(NO_(3))_(3)(aq) were used in catalytic oxidation of ethyl acetate.Characterization by X-ray diffractometer(XRD),H2 temperature programmed reduction(H2-TPR),X-ray photoelectron spectroscopy(XPS) and Raman shows that La/Ce_(0.5)Mn_(0.5) catalysts have fluorite-like structure.LalCe_(0.5)Mn_(0.5) catalyst presents high activity with T90(the temperature needed for 90% conversion) of 200℃,where ethyl acetate is almost completely converted into CO_(2).The conversion at 195℃ maintains at 80% for at least 100 h.The intermediates were mainly ethanol and acetaldehyde whose amounts are below250 × 10^(-6) and 16 × 10^(-6),respectively.In situ FTIR indicates that the modes of dissociative adsorption of ethyl acetate are related to surface oxygen species,which affect the stability of catalysts and the selectivity for ethanol and acetaldehyde intermediates.

Therapeutic potential of ethyl acetate fraction of Tephrosia purpurea Linn.leaves in a rat model of gout

Objective: The present study is to determine the potential treatment effects of ethyl acetate fraction of Tephrosia purpurea Linn. leaves(EATP) against gout.Methods: Gout in experimental rats was induced with potassium oxonate at the dose of 250 mg/kg(intraperitoneal injection) for 7 consecutive days;EATP was administered 1 h after administration of the potassium oxonate on each day of experiment. Potassium oxonate was discontinued on the 8 th day;thereafter allopurinol(10 mg/kg, p.o.) and EATP(200 and 400 mg/kg, p.o.) were continued until day 14. The uric acid level was measured from serum and urine during the experiment. Other biochemical parameters were assessed, including blood and urine creatinine, erythrocyte sedimentation rate, and total protein. Blood urea nitrogen, serum aspartate aminotransferase serum alanine aminotransferase and alkaline phosphatase were also measured. The blood was analyzed for levels of malondialdehyde and the antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase.Histopathological and radiological changes in the ankle of rats were observed after completion of the experiment.Results: EATP was able to decrease serum uric acid and creatinine level;it also reduced inflammation,oxidative stress and lysosomal enzyme level, which has a role in acute inflammation. EATP increased uric acid excretion through urine due to its uricosuric effect.Conclusion: EATP lowered the serum uric acid level and increased the urine uric acid level through excretion, which is useful in the treatment of gout. Hence the EATP was found to be helpful in the treatment of gout.

Ethyl Acetate Fraction in Hedyotis Diffusa Willd Inhibits T Cell Proliferation to Improve the Pathogenesis of Systemic Lupus Erythematosus

Background:Abnormal proliferation of T cells plays an essential role in the pathogenesis of Systemic lupus erythematosus(SLE).The pharmaceutical effect of Hedyotis Diffusa Willd(HDW)on SLE has been investigated previously.Nevertheless,the biomedical mechanism is still left unclear.Objective:This study has been arranged to evaluate the therapeutic effect of the ethyl acetate fraction of HDW(EAHDW)on lupus mice and explore the potential therapeutic mechanism.Methods:EAHDW was prepared with 80%ethanol reflex extraction followed by successive extraction,and ana-lyzed with HPLC and UPLC-Q/TOP-MS.The potential targets and STAT3 affinity regulators were predicted with network pharmacology.The pharmaceutic effect of EAHDW was studied with MRL/lpr mice.Cytokines and au-toantibodies were quantified with ELISA assays.The pathological damage of glomerulus and STAT3 expression in the kidney was detected with histochemical and immunohistochemical techniques.The cell cycle properties in cell proliferation were identified with the flow cytometry.The western blot and dual-Luciferase reporter assay were applied to evaluate translational and transcriptional activity of STAT3,respectively.Results:In this study,the extraction ratio of EAHDW was 2.7±1%,in which 19 ingredients were identified.Network pharmacological analysis showed that the target genes of EAHDW were highly focused on influencing the abnormal T cell proliferation in SLE.EAHDW showed the beneficial effects on pathological changes and STAT3 expression in the glomerulus of lupus mice,and the levels of cytokines and autoantibodies in serum.In cytological study,EAHDW treatment attenuated the transcription and phosphorylation of STAT3,which inhibited T cell proliferation by prolonged S-phase of the cell cycle.A total of 5 compounds in EAHDW exhibited high docking affinity to the DNA-binding site of STAT3.Conclusion:EAHDW could reduce the inflammatory response and inhibit the proliferation of T cells by interfering with the STAT3 signaling pathway,thereby playing a therapeutic effect on SLE.

A Novel Process Using Ion Exchange Resins for the Coproduction of Ethyl and Butyl Acetates

Before proposing an innovative process for the coproduction of ethyl and butyl acetates, the individual syntheses of ethyl acetate and butyl acetate by two different routes were first studied. These syntheses involved the reaction of ethanol or n-butanol with acetic acid or acetic anhydride in the presence of ion exchange resins: Amberlyst 15, Amberlyst 16, Amberlyst 36 and Dowex 50WX8. Kinetic and thermodynamic studies were performed with all resins. The lowest activation energy (Ea) value was obtained with Dowex 50WX8, which was identified as the best-performing resin, able to be reused at least in four runs without regeneration. The presence of water-azeotropes during the synthesis of ethyl acetate makes its purification difficult. A new strategy was adopted here, involving the use of ethanol and acetic anhydride as the starting material. In order to minimize acetic acid as co-product of this reaction, a novel two-step process for the coproduction of ethyl and butyl acetates was developed. The first step involves the production of ethyl acetate and its purification. Butyl acetate was produced in the second step: n-butanol was added to the mixture of acetic acid and the resin remaining after the first-step distillation. This process yields ethyl acetate and butyl acetate at high purity and shows an environmental benefit over the independent syntheses by green metrics calculation and life cycle assessment.

Antibacterial activity of the ethyl acetate part of Abrus cantoniensis against Staphylococcus aureus

Objective:The aim of this work was to measure the antibacterial activity(against Escherichia coli and Staphylococcus aureus[S.aureus])of the ethyl acetate part of Abrus cantoniensis and assess their potential as medicines.Methods:The experiment was divided into four groups:negative control group[with Mueller-Hinton broth(MHB)],positive control group(with 75%ethanol),blank group(with MHB)and test group(with the ethyl acetate part of Abrus cantoniensis).The antibacterial activities of the extracts were evaluated by the Oxford cup assay and minimum inhibitory concentration(MIC).Time-kill curve experiments,scanning electron microscopy,the content of DNA,RNA and protein were used to study the antibacterial mechanism of the ethyl acetate extract part on the growth and viability of S.aureus.The study procedures were approved by the Animal Care and Use Committee of Xi’an Jiaotong University(approval No.XJTULAC2016-412)on January 22,2016.Results:The ethyl acetate part of Abrus cantoniensis extract exhibited the highest inhibitory activity against the growth of S.aureus with an inhibition zone diameter of 16.4mm and MIC value of 0.5mg/mL.The general activity range of the ethyl acetate part,determined using a time-killing curve,was found to be 0.5mg/mL to 40mg/mL(MIC to 80
MIC).Changes in the scanning electron microscopy images and of DNA,RNA and proteins of S.aureus indicated possible mechanisms of the inhibitory activity of the ethyl acetate part.Conclusion:The ethyl acetate part of Abrus cantoniensis damaged bacterial cell structures,which results in protoplasm leakage,and eventually bacterial cell death.

Introducing cerium into TiO_(2)@MnO_(x) hollow-sphere structure for highly active photothermocatalysis degradation of ethyl acetate and NO under H_(2)O at low temperature

The CeO_(2)-TiO_(2)@MnO_(x) catalyst was prepared by the co-precipitation method and applied to the photothermocatalysis system of ethyl acetate and NO simultaneous degradation under H_(2)O at low temperature,which introduced Ce into TiO_(2)@MnO_(x) hollow sptrera structure.The optimum TiO_(2)/MnO_(x) ratio and Ce introducing amount were obtained in the process.Among of them,the NO and ethyl acetate conversion percentage of TiO_(2)@MnO_(x)(n_(Mn):n_(Ti)=40:40)is 74%and 62%at 240℃,respectively.CeO_(2)-TiO_(2)@MnO_(x)(n_(Mn):n_(Ce)=1:1)exhibits the best catalytic performance,its efficiency for NO conversion is 83%and the conversion of ethyl acetate reaches 72%at 240℃.In addition,it is confirmed that the Cedoped nanocomposites have more uniform dispersion through various characterization and analysis methods.Meanwhile,these catalysts have a large specific surface area as well as a large number of surface-active oxygen and oxygen vacancies.It can further improve the catalytic performance based on the adjusted ratio of active components.Moreover,this work investigated the relationship between multi-metal interactions and catalytic performance in the presence of H_(2)O.Finally,the possible reaction pathways for the simultaneous removal of NO and ethyl acetate were explored in our system.

Chemical Composition of Fruit of Embelia undulata(Wall.)Mez

[Objectives]To study the chemical constituents of the fruit of Embelia undulata(Wall.)Mez.[Methods]Silica gel column chromatography,gel column chromatography,recrystallization,high-performance preparative liquid chromatography and other modern separation methods and techniques were used to separate and purify the chemical components of the ethyl acetate fraction of the fruit of E.undulata(Wall.)Mez,and based on the physical and chemical properties and spectral data,their structure was identified.[Results]Six compounds were isolated from the fruit of E.undulata(Wall.)Mez,including trimethyl citrate(1),vanillic acid(2),5-hydroxymethylfurfural(3),1,5-dimethyl citrate(4),1,6-dimethyl-5-ethyl citrate(5)and 3,4-dihydroxybenzoic acid(6).[Conclusions]Compounds 1-6 are all isolated from E.undulata(Wall.)Mez for the first time.

Optimization of modified clean fractionation of prairie cordgrass

In this study,modified clean fractionation process was optimized for prairie cordgrass,with usage of alternative organic constituent-ethyl acetate.Other constituents of the solvent mixture included ethanol and water.Clean fractionation solvent was used in different proportions of the constituents.Process efficiency was determined by lignin recovery,solvent composition,as well as time and temperature applied to each sequential process.Glucose yield during enzymatic hydrolysis and overall pretreatment were calculated.Optimal conditions(125℃,37 min,with the solvent composition of ester:ethanol:water=32.5:22.5:45)yielded a 20%lignin recovery,38%glucose yield during enzymatic hydrolysis and 26%xylose recovery in aqueous fraction.