Improved Production of Paclitaxel from Suspension Culture of Taxus chinensis var. mairei by in situ Extraction with Organic Solvents

The production of paclitaxel from suspension culture of Taxus chinensis var,mairei was improved by in situ extraction with organic solvents to avoid feedback repression and product degradation.Oleic acid and dibutyl phthalate were proved to be suitable solvents .The optimal volumetric percentage of organic solvents in the culture medium was found to be around 8%,and the favorable time for their introduction was at the exponential phase of cell growth,Paclitaxel production with the in situ extraction was ca 3-fold of that without extraction.

Distribution and sources of solvent extractable organic compounds in PM_(2.5) during 2007 Chinese Spring Festival in Beijing

The solvent extractable organic compounds （SEOC）, including n-alkanes, polycylic aromatic hydrocarbons, fatty acids, and dicarboxylic acids in PM2.5 during the 2007 Chinese Spring Festival in Beijing, were measured via gas chromatography-mass spectrometry for determining the characteristics and sources of these organic pollutants. The concentrations of total n-alkanes, PAHs, and organic acids before Chinese Spring Festival Eve （1025.5, 95.9, and 543.3 ng/m3, respectively） were higher than those after （536.6, 58.9, and 331.8 ng/m3, respectively）, n-Aalkanes and PAHs had much higher concentration in nighttime than those in daytime because of high relative humidity and low wind speed during the night. Combustion of coal and exhaust emission were major sources of n- alkanes. It could be concluded by the characteristic ratios that the primary source of PAHs in fine particles was the combustion of coal, but the combustion of gasoline was in the next place. The ratios of C18：0/C16 indicated the contribution of vehicular emissions to the fatty acids. Dicarboxylic and aromatic acids were abundant in daytime than in nighttime because these acids were secondary organic acid and the photochemical degradation of aromatic hydrocarbons was the main source.

Extraction of Tungsten and Molybdenum by Various Organic Compounds as Extractants

Seventy organic compounds including various organophosphorus esters, amines and oxygen-based ligands were investigated as extractants. The experiment results show that amines are excellent extractants for W and Mo. Their sequence of extraction ability for W is as follows: quarternary amine > tertiary amine > secondary amine > primary amine. Acidic organophosphorus extractants do not extract W, but can extract Mo with high extraction ability from the acidic solution. These extractants could provide a potential process for separating W from Mo.

Supercritical water oxidation of spent extraction solvent simulants

The rapid development of nuclear technology has led to more liquid organic radioactive wastes. Different from the regular aqueous radioactive wastes, these liquids possess a higher hazard potential and cannot be disposed through the conventional methods due to their radioactivity and chemical nature. Spent extraction solvent is a kind of common liquid organic radioactive wastes. In this work, tri-butyl phosphate(TBP), which is more difficult to degrade in the spent extraction solvent, was used as the model compound. Influences of reaction conditions on total organic carbon(TOC) removal and the volume percentage of each gas component under supercritical water oxidation(SCWO) were studied. The SCWO behaviors of spent extraction solvent simulants were studied under the optimal conditions derived from the TBP experiment. The SCWO experiments were studied at 400–550℃, oxidant stoichiometric ratio of 0–200%, feed concentration of 1.5%–4% and pressure of25 MPa for 15–75 s. The results show that the TOC removal of the simulants was greater than 99.7% and CH4,H2 and CO were not detected at 550℃, 25 MPa, oxidant stoichiometric ratio of 150%, feed concentration of3%, and residence time of 30 s.

Shale Oil Solvent Extraction of Central Jordan El-Lajjun Oil Shale

The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In this work, organic solvents extraction experiments were implemented to investigate the effect of various parameters on Jordanian El-Lajjun oil shale extractability. Results indicate that the approximate organic matter content in studied El-Lajjun oil shale is 17.48%, and 75% of OS sample particles diameters are less than 270 μm. The grain size has minor effect on shale oil extraction via organic solvents. Among eleven solvents used, the highest yield is obtained via the tetrahedrofuran (THF), whereas, with the use of solvent mixtures, the highest bitumen yield is obtained through the mixture of THF and toluene. The solvation variability is related to mode of extraction and various physicochemical factors such as extraction temperature, pressure, solvent type and mixing time, which result in different OM yield. The results indicate that the solvent extraction could be potential for shale oil extraction from Jordanian El-Lajjun OS under certain conditions of temperature, pressure and solvent type used.

Effect of diluent on interfacial emulsion in copper solvent extraction

The organic phase extracted from interfacial crud of copper solvent extraction at Dexing Copper Mine was analyzed for its different components by combined gas chromatography mass spectroscopy. It was found that the main impurities in organic phase were methylnaphthalenes and di methylnaphthalenes which originated from commercial 260# kerosene used as diluent. It was found that the impurities containing diluent was unfavorable to phase disengagement. Methods were suggested to improve diluent properties to prevent stable interfacial emulsion.

Determination of Five (5) Possible Contaminants in Recycled Cardboard Packages and Food Simulants Using Ultrasound Assisted Extraction Coupled to GC-MS

A modified analytical procedure has been developed to test for 5 organic pollutants [benzophenone, 2 diisopropylnaphthalenes (DIPNs) {2,6- and 2,7-diisopropylnapthalene} and 2 hydrogenated terphenyls (HTPs) {m-terphenyl and o-terphenyl}] that can be found as residues in recycled cardboards intended for use as food packaging materials and to test for migration levels of these compounds in a food simulant (Tenax). A main objective was to develop a modified rapid and reliable method for the identification and quantification of these compounds at low concentrations. The method was based on ultrasound-assisted solvent extraction (UAE) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The developed method was applied to analyze 3 commercially available recycled carton board food-packaging materials and also to study the potential migration of the 5 organic pollutants from these materials into Tenax to check if these recycled cardboards can be considered as suitable for use in direct contact with foodstuffs. The limits of detection (LODs) of standard solutions of the 5 compounds were determined at a signal-to-noise ratio of 3. The LODs and the limits of quantification (LOQs) of examined pollutants ranged between 0.005 to 0.5 mg/kg, and 0.1 to 1 mg/kg, respectively. The extremely low amounts of most contaminants that migrate from packaging materials to Tenax indicate that the recycled cardboards tested can be safely used for direct food contact applications.

Analysis of volatile components in saffron from Tibet and Henan by ultrasonic-assisted solvent extraction and GC-MS

To determine the chemical constituents of volatile components in saffron from the Tibet Autonomous Region and the Henan Province of China and to compare the chemical composition difference in the saffron,the total volatile components were extracted by ultrasonic-assisted solvent extraction（USE）,using five different solvents：diethyl ether,ethanol,ethyl acetate, dichloromethane and acetone,analyzed using gas chromatography-mass spectrometry（GC-MS）and compared to the standard MS data,and their relative contents were calculated by area normalization.The results showed both that USE was an efficient and rapid method for the extraction of the volatile components from saffron and that the components extracted from the same sample using different solvents were different.Comparison of the experimental results of saffron from the Tibet Autonomous Region and the Henan Province of China showed that their volatile components were different in their chemical composition and in their relative percentages.USE/GC-MS is a simple,rapid,and effective method for the analysis of volatile oil components in saffron.

Affinity Solvents for Intensified Organics Extraction: Development Challenges and Prospects

In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are： Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules.

Antimicrobial Activity of Polyalthia longifolia (Sonn.) Thw. var. Pendula Leaf Extracts Against 91 Clinically Important Pathogenic Microbial Strains

The methanol, acetone and 1,4-dioxan fractions of leaves of Polyalthia longifolia (Sonn.) Thw. were evaluated for antibacterial and antifungal activity. 91 clinically important strains were used for the study which were both clinical isolates as well as identified strains. Piperacillin and gentamicin were used as standards for antibacterial assay, while nystatin and flucanazole were used as standards for antifungal assay. The antibacterial activity was more pronounced against gram positive bacterial and fungal strains. Poor activity was shown against gram negative bacterial strains studied.

Allelopathic Effects of Corrigiola Telephiifolia Root Extracts on Germination and Seedling Growth of Raphanus Sativus and Triticum Aestivum

The allelopathic potential of aqueous and organic solvent extacts from Corrigiola telephiifolia Pour which is an aromatic and medicinal plant in mediterranean regions, was investigated under laboratory conditions on two plant species： Raphanus sativus and Triticum aestivum. The aqueous extract of Corrigiola telephiifolia roots had an important inhibitory effect on the seed germination of the two tested plant species. The dichloromethane and the methanol extracts significantly reduced the growth of radish roots up to 84.44% and 68.85% respectively. The butanol, the dichloromethane and the ethyl acetate extracts had a high inhibitory effect on seed germination and roots growth of wheat. The presence of saponins in butanol extracts and tanins in dichlorometane and ethyl acetate extracts may be responsible of these allelopathic activities. These results suggest that Corrigiola telephiifolia Pour have allelopathic effects and contains potent allelochemicals which should be used for weeds management.

真空冻干/快速溶剂萃取-气相色谱-质谱法测定土壤中35种不同种类半挥发性有机物

建立了真空冻干/快速溶剂萃取-气相色谱-质谱法(GC-MS)测定土壤中35种不同种类半挥发性有机物(SVOCs)的方法。样品经真空冷冻脱水、快速溶剂萃取、旋转蒸发浓缩以及固相萃取SPE小柱净化后,氮吹定容,采用GC-MS上机测定。结果表明:土壤中35种SVOCs在10~1000μg/L范围内线性相关系数r^(2)≥0.991,方法检出限为0.034~0.40μg/kg,方法定量限为0.14~1.20μg/kg;以空白样品为基体进行加标回收实验,所得加标回收率为71.2%~113%,相对标准偏差(RSDs,n=7)为0.38%~13.3%,替代物荧蒽-D 10回收率为84.0%~92.5%;经实际样品检测验证,该方法灵敏、快速、准确可靠,适用于土壤中35种不同种类SVOCs的分析检测。

富锗木耳菌丝体不同溶剂提取物的体外抗氧化能力

为探索富锗木耳菌丝体不同溶剂提取物的体外抗氧化能力,以富锗木耳菌丝体为材料,通过水、70%乙醇和乙酸乙酯对富锗木耳菌丝体进行了物质提取,比较了不同提取物对超氧阴离子自由基、羟自由基和DPPH自由基的清除能力。采用隶属函数值评价了不同溶剂提取物的综合抗氧化能力,并对物质含量与抗氧化能力进行了相关性分析。结果表明:富锗木耳菌丝体有机锗含量为542.83μg/g。不同溶剂提取物的提取率和物质含量均不同,水和乙醇提取物的提取率较高,水提取物中多糖含量最多,乙酸乙酯提取物中多酚和黄酮含量最多。不同溶剂提取物对自由基均有一定的清除能力,且随着提取物浓度的增加而增加。水提取物对超氧阴离子自由基清除率最强,当提取物浓度为9 mg/mL时,清除率最高为43.32%。70%乙醇提取物对羟自由基和DPPH自由基的清除效果最好,当提取物浓度为9 mg/mL时,清除率分别为70.10%和76.99%。多糖、多酚和黄酮在清除自由基中均发挥不同的作用,70%乙醇提取物的综合抗氧化能力最强。多糖、多酚和黄酮含量均与DPPH自由基清除率有显著(P<0.05)正相关。70%乙醇提取物中多酚含量与羟自由基清除率有显著(P<0.05)正相关。多糖、多酚及黄酮对超氧阴离子自由基的清除率均有显著(P<0.05)影响。富锗木耳菌丝体含有较高含量的有机锗,提取物对自由基具有一定的清除能力,具有较好的抗氧化性能。本研究对开发富锗木耳功能食品具有一定指导意义。

不同分离方法分离烃源岩可溶有机质的对比实验

对加速溶剂萃取与索式提取两种烃源岩可溶有机质分离方法的分离总量、分离效率、可溶有机质的化学与分子组成进行了对比。结果表明:加速溶剂萃取分离出的可溶有机质总量略低于索式提取,但分离效率远高于索式提取;加速溶剂萃取所得的可溶有机质中饱和烃与芳香烃的相对百分含量高于索式提取,非烃与沥青质的相对百分含量低于索式提取;两种分离方法所得的可溶有机质中高碳数饱和烃与芳香烃化合物的分布形态、地球化学比值参数和绝对含量均具有很好的可比性,相反,二环倍半萜系列化合物显示较大差异,加速溶剂萃取所得可溶有机质的低碳数、低沸点的二环倍半萜化合物的相对百分含量高于索式提取。

顶空-气相色谱法测定到手香提取物11种溶剂残留量

目的建立顶空-气相色谱法测定中药到手香提取物中苯、丙烯腈、甲基丙烯酸甲酯、甲苯、1,2-二氯乙烷、对二甲苯、间二甲苯、邻二甲苯、氯苯、苯乙烯和二乙烯苯11种溶剂残留的分析方法。方法供试品经顶空进样器85℃平衡45 min,分流比10∶1(V∶V),采用DB-WAX聚乙二醇为固定相的弹性石英毛细管柱(长30 m,内径0.32 mm,膜厚0.5μm),FID氢火焰离子化检测器进行分析。结果11种挥发性有机物分离效果较好,在0.22~23.86μg·mL^(-1)的浓度范围内线性关系良好(r≥0.99);方法定量限为0.0084μg·mL^(-1)≤LOQ≤0.5432μg·mL^(-1);低、中、高水平下各成分的平均回收率为84%~103%之间;相对标准偏差≤10%(n=6),经方法学验证后该方法符合实验要求。3批样品中甲苯、间二甲苯、邻二甲苯及二乙烯基苯有检出,低于定量限,均未超标。结论该方法易于操作,结果可靠,可用于中药到手香提取物中的残留溶剂检测,亦为其他中药提取物中残留溶剂分析提供方法参考,确保用药安全。

现代化萃取技术在水环境监测中的应用研究

水环境监测中,快速溶剂萃取技术具备所需溶剂少、萃取率高、损耗时间短等显著应用优势,是一种典型的样品前处理技术。基于此,就该项技术的作用机理、工艺流程以及应用范围进行分析,并对其实践应用前景进行深入研究,以期促进该技术的进一步发展应用。

聚羟基脂肪酸酯的萃取精制工艺研究

为推动中国新型生物基高分子材料的全面发展,促进生物基材料PHA的高值化应用,通过筛选萃取剂种类和用量、预处理试剂种类和用量以及预处理时间,确定了PHA样品最佳萃取工艺参数,并显著提高了PHA产品的质量和回收效率。结果表明,最佳预处理试剂为次氯酸钠,萃取剂为三氯甲烷,2种试剂的使用量分别是PHA样品质量的14倍和19倍,预处理时间1.5 h时发酵效果最好,最终纯度和回收率分别为98.35%和89.60%。该研究以三氯甲烷和次氯酸钠萃取PHA,显著提升PHA纯度和回收率,并简化提取工艺,为推进生物基材料PHA的下游分离提取工作提供有力的理论支持。

蔗渣水解液酸催化制备糠醛及其萃取分离

首先,蔗渣在高温下通过酸性水解制备了水解液和水解渣;然后,水解液经深度酸解制备了糠醛,并以有机溶剂萃取分离了水相中的糠醛;水解渣经硫酸盐蒸煮制备了浆料纤维。采用FTIR、XRD、SEM、TG对蔗渣及水解渣进行了表征,利用UV-Vis吸收光谱对水解液中的木糖及深度酸解液中的糠醛进行了定量检测。对蔗渣预水解条件、糠醛的有机溶剂萃取条件进行了考察。结果表明,在反应温度160℃、液固比(mL∶g)为6∶1、浓硫酸用量为0.176%(以绝干蔗渣质量计,下同)的条件下,预水解反应3 h后,水解液中木糖质量浓度最高(41.72 g/L);水解液在170℃下深度酸解90 min,深度酸解液中糠醛质量浓度最高可达15.91 g/L,糠醛收率最高为59.60%。以V(1,2-二氯乙烷)∶V(正丁醇)=9∶1的混合溶剂萃取深度酸解液中糠醛(有机相与水相体积比为2∶1),糠醛分配系数最高为7.62,糠醛的萃取率可达93.53%。浆料中α-纤维素质量分数高达93.41%,纤维长径比为29.9,细小纤维占比34.7%。

玉米叶绿素含量测定方法研究

以玉米幼苗绿叶为试材,研究了6种叶绿素提取液的吸收光谱和提取效率及低温冷冻对叶绿素提取的影响,结果表明:6种叶绿素提取液的吸收光谱基本相似,可以沿用Arnon法的计算公式进行叶绿素含量的测定;室温下,浸提法要优于研磨法,混合液浸提叶绿素比单独用丙酮或乙醇浸提要快,其中丙酮乙醇(水)配伍提取速度较快而稳定,是最佳的叶绿素提取方法。叶片冷冻后快速浸提确实能加速叶绿素提取速度,但叶绿素易受光热破坏,故应注意遮光。

浸提法测定玉米叶绿素含量的改进

以玉米叶片为试材,研究了8种不同有机溶剂浸提液提取叶绿素的效率及低温冷冻对叶绿素提取的影响。试验中采用叶绿素仪先预叶片;冷冻—高温快速浸提试验,采用先称取样品,后冷冻方式。结果表明:室温(25℃)下,浸提法要优于研磨法,混合液浸提叶绿素比单独用丙酮或乙醇浸提快,其中丙酮∶乙醇=2∶1的浸提液浸提速度快而稳,是试验中最佳的叶绿素提取方法。最佳浸提时间在浸提16h时。叶片冷冻处理后,快速浸提能够缩短叶绿素浸提时间。由于受光照、高温的影响,测定值普遍较低。