Selective Solid-liquid Extraction and Liquid-liquid Extraction of Lithium Chloride using Strapped Calix[4]pyrroles

DOE PAGES

He, Qing; Williams, Neil J.; Oh, Ju; ...

2018-05-25

LiCl is a classic "hard" ion salt that is present in lithium-rich brines and a key component in end-of-life materials (i.e., used lithium-ion batteries). Its isolation and purification from like salts is a recognized challenge with potential strategic and economic implications. Here in this paper, we describe two ditopic calix[4]pyrrole-based ion pair receptors (2 and 3), that are capable of selectively capturing LiCl. Under solid-liquid extraction conditions, using 2 as the extractant, LiCl could be separated from a NaCl-KCl salt mixture containing as little as 1% LiCl with ~100% selectivity, while receptor 3 achieved similar separations when the LiCl levelmore » was as low as 200 ppm. Under liquid-liquid extraction conditions using nitrobenzene as the non-aqueous phase, the extraction preference displayed by 2 is KCl > NaCl > LiCl. Lastly, in contrast, 3 exhibits high selectivity towards LiCl over NaCl and KCl, with no appreciable extraction being observed for the latter two salts.« less

Selective Solid-liquid Extraction and Liquid-liquid Extraction of Lithium Chloride using Strapped Calix[4]pyrroles

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Qing; Williams, Neil J.; Oh, Ju

LiCl is a classic "hard" ion salt that is present in lithium-rich brines and a key component in end-of-life materials (i.e., used lithium-ion batteries). Its isolation and purification from like salts is a recognized challenge with potential strategic and economic implications. Here in this paper, we describe two ditopic calix[4]pyrrole-based ion pair receptors (2 and 3), that are capable of selectively capturing LiCl. Under solid-liquid extraction conditions, using 2 as the extractant, LiCl could be separated from a NaCl-KCl salt mixture containing as little as 1% LiCl with ~100% selectivity, while receptor 3 achieved similar separations when the LiCl levelmore » was as low as 200 ppm. Under liquid-liquid extraction conditions using nitrobenzene as the non-aqueous phase, the extraction preference displayed by 2 is KCl > NaCl > LiCl. Lastly, in contrast, 3 exhibits high selectivity towards LiCl over NaCl and KCl, with no appreciable extraction being observed for the latter two salts.« less

Molecularly imprinted polymers based stir bar sorptive extraction for determination of cefaclor and cefalexin in environmental water.

PubMed

Peng, Jun; Liu, Donghao; Shi, Tian; Tian, Huairu; Hui, Xuanhong; He, Hua

2017-07-01

Although stir bar sportive extraction was thought to be a highly efficiency and simple pretreatment approach, its wide application was limited by low selectivity, short service life, and relatively high cost. In order to improve the performance of the stir bar, molecular imprinted polymers and magnetic carbon nanotubes were combined in the present study. In addition, two monomers were utilized to intensify the selectivity of molecularly imprinted polymers. Fourier transform infrared spectroscopy, scanning electron microscopy, and selectivity experiments showed that the molecularly imprinted polymeric stir bar was successfully prepared. Then micro-extraction based on the obtained stir bar was coupled with HPLC for determination of trace cefaclor and cefalexin in environmental water. This approach had the advantages of stir bar sportive extraction, high selectivity of molecular imprinted polymers, and high sorption efficiency of carbon nanotubes. To utilize this pretreatment approach, pH, extraction time, stirring speed, elution solvent, and elution time were optimized. The LOD and LOQ of cefaclor were found to be 3.5 ng · mL -1 and 12.0 ng · mL -1 , respectively; the LOD and LOQ of cefalexin were found to be 3.0 ng · mL -1 and 10.0 ng · mL -1 , respectively. The recoveries of cefaclor and cefalexin were 86.5 ~ 98.6%. The within-run precision and between-run precision were acceptable (relative standard deviation <7%). Even when utilized in more than 14 cycles, the performance of the stir bar did not decrease dramatically. This demonstrated that the molecularly imprinted polymeric stir bar based micro-extraction was a convenient, efficient, low-cost, and a specific method for enrichment of cefaclor and cefalexin in environmental samples.

Ultra-preconcentration and determination of selected pharmaceutical and personal care products in different water matrices by solid-phase extraction combined with dispersive liquid-liquid microextraction prior to ultra high pressure liquid chromatography tandem mass spectrometry analysis.

PubMed

Celano, Rita; Piccinelli, Anna Lisa; Campone, Luca; Rastrelli, Luca

2014-08-15

Pharmaceutical and personal care products (PPCPs) are one of the most important classes of emerging contaminants. The potential of ecological and environmental impacts associated with PPCPs are of particular concern because they continually penetrate the aquatic environment. This work describes a novel ultra-preconcentration technique for the rapid and highly sensitive analysis of selected PPCPs in environmental water matrices at ppt levels. Selected PPCPs were rapidly extracted and concentrated from large volumes of aqueous solutions (500 and 250mL) by solid-phase extraction combined with dispersive liquid-liquid microextraction (SPE-DLLME) and then analyzed using UHPLC-MS/MS. Experimental parameters were carefully investigated and optimized to achieve the best SPE-DLLME efficiency and higher enrichment factors. The best results were obtained using the ternary mixture acetonitrile/methanol/dichloromethane 3:3:4, v/v/v, both as SPE eluent and DLLME extractant/dispersive mixture. DLLME aqueous solution (5% NaCl, 10mgL(-1) TBAB) was also modified to improve the extraction efficiency of more hydrophilic PPCPs. Under the optimal conditions, an exhaustive extraction for most of the investigated analytes (recoveries >70%), with a precision (RSD <10%) and very high enrichment factors were attained for different aqueous matrices (drinking, sea, river and wastewater). Method detection and quantification limits were at very low ppt levels and below 1 and 3ngL(-1), respectively, for 15 of selected PPCPs. The proposed analytical procedure offers numerous advantages such as the simplicity of operation, rapidity, a high enrichment factor and sensitivity. So it is suitable for monitoring and studies of occurrence of PPCPs in different environmental compartments. Copyright © 2014 Elsevier B.V. All rights reserved.

Unique low-molecular-weight lignin with high purity extracted from wood by deep eutectic solvents (DES): a source of lignin for valorization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez-Vasco, Carlos; Ma, Ruoshui; Quintero, Melissa

This paper reports a new method of applying Deep Eutectic Solvents (DES) for extracting lignin from woody biomass with high yield and high purity. DES mixtures prepared from Choline Chloride (ChCl) and four hydrogen-bond donors–acetic acid, lactic acid, levulinic acid and glycerol–were evaluated for treatment of hardwood (poplar) and softwood (D. fir). It was found that these DES treatments can selectively extract a significant amount of lignin from wood with high yields: 78% from poplar and 58% from D. fir. The extracted lignin has high purity (95%) with unique structural properties. We discover that DES can selectively cleave ether linkagesmore » in wood lignin and facilitate lignin removal from wood. The mechanism of DES cleavage of ether bonds between phenylpropane units was investigated. The results from this study demonstrate that DES is a promising solvent for wood delignification and the production of a new source of lignin with promising potential applications.« less

Effective synthesis of magnetic porous molecularly imprinted polymers for efficient and selective extraction of cinnamic acid from apple juices.

PubMed

Shi, Shuyun; Fan, Dengxin; Xiang, Haiyan; Li, Huan

2017-12-15

An effective strategy was proposed to prepare novel magnetic porous molecularly imprinted polymers (MPMIPs) for highly selective extraction of cinnamic acid (CMA) from complex matrices. Characterization and various parameters affecting adsorption and desorption behaviors were investigated. Results revealed adsorption behavior between CMA and MPMIPs followed Freundlich equation adsorption isotherm with a maximum adsorption capacity at 4.35mg/g and pseudo-second-order reaction kinetics with equilibrium time at 60min. Subsequently, MPMIPs were successfully used to selectively extract CMA from apple juice with a relatively satisfactory recovery (92.7-101.4%). Coupling with high-performance liquid chromatography and ultraviolet detection (HPLC-UV), the limit of detection (LOD) for CMA was 0.006µg/mL, and the linear range (0.02-10μg/mL) was wide with correlation coefficient at 0.9995. Finally, the contents of CMA in two kinds of apple juices were determined as 0.132 and 0.120μg/mL. Results indicated the superiority of MPMIPs in the selective extraction field. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dispersive solid-phase extraction based on magnetic dummy molecularly imprinted microspheres for selective screening of phthalates in plastic bottled beverages.

PubMed

Qiao, Jindong; Wang, Mingyu; Yan, Hongyuan; Yang, Gengliang

2014-04-02

A new magnetic dummy molecularly imprinted dispersive solid-phase extraction (MAG-MIM-dSPE) coupled with gas chromatography-FID was developed for selective determination of phthalates in plastic bottled beverages. The new magnetic dummy molecularly imprinted microspheres (MAG-MIM) using diisononyl phthalate as a template mimic were synthesized by coprecipitation coupled with aqueous suspension polymerization and were successfully applied as the adsorbents for MAG-MIM-dSPE to extract and isolate five phthalates from plastic bottled beverages. Validation experiments showed that the MAG-MIM-dSPE method had good linearity at 0.0040-0.40 μg/mL (0.9991-0.9998), good precision (3.1-6.9%), and high recovery (89.5-101.3%), and limits of detection were obtained in a range of 0.53-1.2 μg/L. The presented MAG-MIM-dSPE method combines the quick separation of magnetic particles, special selectivity of MIM, and high extraction efficiency of dSPE, which could potentially be applied to selective screening of phthalates in beverage products.

The Best Extraction Technique for Kaempferol and Quercetin Isolation from Guava Leaves (Psidium guajava)

NASA Astrophysics Data System (ADS)

Batubara, I.; Suparto, I. H.; Wulandari, N. S.

2017-03-01

Guava leaves contain various compounds that have biological activity such as kaempferol and quercetin as anticancer. Twelve extraction techniques were performed to obtain the best extraction technique to isolate kaempferol and quercetin from the guava leaves. Toxicity of extracts was tested against Artemia salina larvae. All extracts were toxic (LC50 value less than 1000 ppm) except extract of direct soxhletation on guava leaves, and extract of sonication and soxhletation using n-hexane. The extract with high content of total phenols and total flavonoids, low content of tannins, intense color of spot on thin layer chromatogram was selected for high performance liquid chromatography analysis. Direct sonication of guava leaves was chosen as the best extraction technique with kampferol and quercetin content of 0.02% and 2.15%, respectively. In addition to high content of kaempferol and quercetin, direct sonication was chosen due to the shortest extraction time, lesser impurities and high toxicity.

High-resolution gas chromatography/mas spectrometry method for characterization and quantitative analysis of ginkgolic acids in ginkgo biloba plants, extracts, and dietary supplements

USDA-ARS?s Scientific Manuscript database

A high resolution GC/MS with Selected Ion Monitor (SIM) method focusing on the characterization and quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba L. plant materials, extracts and commercial products was developed and validated. The method involved sample extraction with (1:1) meth...

Selective extraction and determination of chlorogenic acids as combined quality markers in herbal medicines using molecularly imprinted polymers based on a mimic template.

PubMed

Ji, Wenhua; Zhang, Mingming; Yan, Huijiao; Zhao, Hengqiang; Mu, Yan; Guo, Lanping; Wang, Xiao

2017-12-01

We describe a solid-phase extraction adsorbent based on molecularly imprinted polymers (MIPs), prepared with use of a mimic template. The MIPs were used for the selective extraction and determination of three chlorogenic acids as combined quality markers for Lonicera japonica and Lianhua qingwen granules. The morphologies and surface groups of the MIPs were assessed by scanning electron microscopy, Brunauer-Emmett-Teller surface area analysis, and Fourier transform infrared spectroscopy. The adsorption isotherms, kinetics, and selectivity of the MIPs were systematically compared with those of non-molecularly imprinted polymers. The MIPs showed high selectivity toward three structurally similar chlorogenic acids (chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid). A procedure using molecularly imprinted solid-phase extraction coupled with high-performance liquid chromatography was established for the determination of three chlorogenic acids from Lonicera japonica and Lianhua qingwen granules. The recoveries of the chlorogenic acids ranged from 93.1% to 101.4%. The limits of detection and limits of quantification for the three chlorogenic acids were 0.003 mg g -1 and 0.01 mg g -1 , respectively. The newly developed method is thus a promising technique for the enrichment and determination of chlorogenic acids from herbal medicines. Graphical Abstract Mimic molecularly imprinted polymers for the selective extraction of chlorogenic acids.

Ionic liquid-impregnated agarose film two-phase micro-electrodriven membrane extraction (IL-AF-μ-EME) for the analysis of antidepressants in water samples.

PubMed

Mohamad Hanapi, Nor Suhaila; Sanagi, Mohd Marsin; Ismail, Abd Khamim; Wan Ibrahim, Wan Aini; Saim, Nor'ashikin; Wan Ibrahim, Wan Nazihah

2017-03-01

The aim of this study was to investigate and apply supported ionic liquid membrane (SILM) in two-phase micro-electrodriven membrane extraction combined with high performance liquid chromatography-ultraviolet detection (HPLC-UV) for pre-concentration and determination of three selected antidepressant drugs in water samples. A thin agarose film impregnated with 1-hexyl-3-methylimidazolium hexafluorophosphate, [C 6 MIM] [PF 6 ], was prepared and used as supported ionic liquid membrane between aqueous sample solution and acceptor phase for extraction of imipramine, amitriptyline and chlorpromazine. Under the optimized extraction conditions, the method provided good linearity in the range of 1.0-1000μgL -1 , good coefficients of determination (r 2 =0.9974-0.9992) and low limits of detection (0.1-0.4μgL -1 ). The method showed high enrichment factors in the range of 110-150 and high relative recoveries in the range of 88.2-111.4% and 90.9-107.0%, for river water and tap water samples, respectively with RSDs of ≤7.6 (n=3). This method was successfully applied to the determination of the drugs in river and tap water samples. It is envisaged that the SILM improved the perm-selectivity by providing a pathway for targeted analytes which resulted in rapid extraction with high degree of selectivity and high enrichment factor. Copyright © 2017 Elsevier B.V. All rights reserved.

Simultaneous determination of phenolic compounds in Equisetum palustre L. by ultra high performance liquid chromatography with tandem mass spectrometry combined with matrix solid-phase dispersion extraction.

PubMed

Wei, Zuofu; Pan, Youzhi; Li, Lu; Huang, Yuyang; Qi, Xiaolin; Luo, Meng; Zu, Yuangang; Fu, Yujie

2014-11-01

A method based on matrix solid-phase dispersion extraction followed by ultra high performance liquid chromatography with tandem mass spectrometry is presented for the extraction and determination of phenolic compounds in Equisetum palustre. This method combines the high efficiency of matrix solid-phase dispersion extraction and the rapidity, sensitivity, and accuracy of ultra high performance liquid chromatography with tandem mass spectrometry. The influential parameters of the matrix solid-phase dispersion extraction were investigated and optimized. The optimized conditions were as follows: silica gel was selected as dispersing sorbent, the ratio of silica gel to sample was selected to be 2:1 (400/200 mg), and 8 mL of 80% methanol was used as elution solvent. Furthermore, a fast and sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the determination of nine phenolic compounds in E. palustre. This method was carried out within <6 min, and exhibited satisfactory linearity, precision, and recovery. Compared with ultrasound-assisted extraction, the proposed matrix solid-phase dispersion procedure possessed higher extraction efficiency, and was more convenient and time saving with reduced requirements on sample and solvent amounts. All these results suggest that the developed method represents an excellent alternative for the extraction and determination of active components in plant matrices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dynamic pH junction high-speed counter-current chromatography coupled with microwave-assisted extraction for online separation and purification of alkaloids from Stephania cepharantha.

PubMed

Yuan, Zhiquan; Xiao, Xiaohua; Li, Gongke

2013-11-22

A simple and efficient dynamic pH junction high-speed counter-current chromatography method was developed and further applied to the online extraction, separation and purification of alkaloids from Stephania cepharantha by coupling with microwave-assisted extraction. Mineral acid and organic base were added into the mobile phase and the sample solution, respectively, leading to the formation of a dynamic pH junction in the column and causing focus of alkaloids. Selective focus of analytes can be achieved on the basis of velocity changes of the pH junction through appropriate selection of solvent systems and optimization of additive concentrations. The extract can be directly introduced into the HSCCC for the online extraction, separation and purification of alkaloids from S. cepharantha. Continuous separation can be easily achieved with the same solvent system. Under the optimum conditions, 6.0 g original sample was extracted with 60 mL of the upper phase of hexane-ethyl acetate-methanol-water (1:1:1:1, v/v/v/v) containing 10% triethylamine under 50 °C and 400 W irradiation power for 10 min, the extracts were directly separated and purified by high-speed counter-current chromatography. A total of 5.7 mg sinomenine, 8.3mg 6,7-di-O-acetylsinococuline, 17.9 mg berbamine, 12.7 mg isotetrandrine and 14.6 mg cepharanthine were obtained with purities of 96.7%, 93.7%, 98.7%, 97.3% and 99.3%, respectively. The online method provides good selectivity to ionizable compounds and improves the separation and purification efficiency of the high-speed counter-current chromatography technique. It has good potential for separation and purification of effective compounds from natural products. Copyright © 2013 Elsevier B.V. All rights reserved.

Rapid and selective extraction of multiple macrolide antibiotics in foodstuff samples based on magnetic molecularly imprinted polymers.

PubMed

Zhou, Yusun; Zhou, Tingting; Jin, Hua; Jing, Tao; Song, Bin; Zhou, Yikai; Mei, Surong; Lee, Yong-Ill

2015-05-01

Magnetic molecularly imprinted polymers (MMIPs) were prepared based on surface molecular imprinting using erythromycin (ERY) as template molecule and Fe3O4 nanoparticles as support substrate. The MMIPs possessed high adsorption capacity of 94.1 mg/g for ERY and the imprinting factor was 11.9 indicating good imprinted effect for ERY. Selective evaluation demonstrated favorable selectivity of MMIPs for multiple macrolide antibiotics (MACs). Using MMIPs as adsorptive material, a rapid and convenient magnetic solid-phase extraction (MSPE) procedure was established for simultaneous and selective separation of six MACs in pork, fish and shrimp samples, then the MACs was subjected to high-performance liquid chromatography-ultraviolet (HPLC-UV) analysis. At different fortified concentrations, the extraction recoveries could reach 89.1% and the relative standard deviations were lower than 12.4%. Chromatogram revealed the response signals of MACs in spiked samples were greatly enhanced and matrix interferences were effectively eliminated after treatment with MSPE. The proposed MSPE procedure coupled with HPLC-UV realized selective and sensitive determination of multiple MACs in foodstuff samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Polydopamine-coated magnetic molecularly imprinted polymer for the selective solid-phase extraction of cinnamic acid, ferulic acid and caffeic acid from radix scrophulariae sample.

PubMed

Yin, Yuli; Yan, Liang; Zhang, Zhaohui; Wang, Jing; Luo, Ningjing

2016-04-01

We describe novel cinnamic acid polydopamine-coated magnetic imprinted polymers for the simultaneous selective extraction of cinnamic acid, ferulic acid and caffeic acid from radix scrophulariae sample. The novel magnetic imprinted polymers were synthesized by surface imprinting polymerization using magnetic multi-walled carbon nanotubes as the support material, cinnamic acid as the template and dopamine as the functional monomer. The magnetic imprinted polymers were characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and vibrating sample magnetometry. The results revealed that the magnetic imprinted polymers had outstanding magnetic properties, high adsorption capacity, selectivity and fast kinetic binding toward cinnamic acid, ferulic acid and caffeic acid. Coupled with high-performance liquid chromatography, the extraction conditions of the magnetic imprinted polymers as a magnetic solid-phase extraction sorbent were investigated in detail. The proposed imprinted magnetic solid phase extraction procedure has been used for the purification and enrichment of cinnamic acid, ferulic acid and caffeic acid successfully from radix scrophulariae extraction sample with recoveries of 92.4-115.0% for cinnamic acid, 89.4-103.0% for ferulic acid and 86.6-96.0% for caffeic acid. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Systematic Assessment of Seven Solvent and Solid-Phase Extraction Methods for Metabolomics Analysis of Human Plasma by LC-MS

NASA Astrophysics Data System (ADS)

Sitnikov, Dmitri G.; Monnin, Cian S.; Vuckovic, Dajana

2016-12-01

The comparison of extraction methods for global metabolomics is usually executed in biofluids only and focuses on metabolite coverage and method repeatability. This limits our detailed understanding of extraction parameters such as recovery and matrix effects and prevents side-by-side comparison of different sample preparation strategies. To address this gap in knowledge, seven solvent-based and solid-phase extraction methods were systematically evaluated using standard analytes spiked into both buffer and human plasma. We compared recovery, coverage, repeatability, matrix effects, selectivity and orthogonality of all methods tested for non-lipid metabolome in combination with reversed-phased and mixed-mode liquid chromatography mass spectrometry analysis (LC-MS). Our results confirmed wide selectivity and excellent precision of solvent precipitations, but revealed their high susceptibility to matrix effects. The use of all seven methods showed high overlap and redundancy which resulted in metabolite coverage increases of 34-80% depending on LC-MS method employed as compared to the best single extraction protocol (methanol/ethanol precipitation) despite 7x increase in MS analysis time and sample consumption. The most orthogonal methods to methanol-based precipitation were ion-exchange solid-phase extraction and liquid-liquid extraction using methyl-tertbutyl ether. Our results help facilitate rational design and selection of sample preparation methods and internal standards for global metabolomics.

Systematic Assessment of Seven Solvent and Solid-Phase Extraction Methods for Metabolomics Analysis of Human Plasma by LC-MS

PubMed Central

Sitnikov, Dmitri G.; Monnin, Cian S.; Vuckovic, Dajana

2016-01-01

The comparison of extraction methods for global metabolomics is usually executed in biofluids only and focuses on metabolite coverage and method repeatability. This limits our detailed understanding of extraction parameters such as recovery and matrix effects and prevents side-by-side comparison of different sample preparation strategies. To address this gap in knowledge, seven solvent-based and solid-phase extraction methods were systematically evaluated using standard analytes spiked into both buffer and human plasma. We compared recovery, coverage, repeatability, matrix effects, selectivity and orthogonality of all methods tested for non-lipid metabolome in combination with reversed-phased and mixed-mode liquid chromatography mass spectrometry analysis (LC-MS). Our results confirmed wide selectivity and excellent precision of solvent precipitations, but revealed their high susceptibility to matrix effects. The use of all seven methods showed high overlap and redundancy which resulted in metabolite coverage increases of 34–80% depending on LC-MS method employed as compared to the best single extraction protocol (methanol/ethanol precipitation) despite 7x increase in MS analysis time and sample consumption. The most orthogonal methods to methanol-based precipitation were ion-exchange solid-phase extraction and liquid-liquid extraction using methyl-tertbutyl ether. Our results help facilitate rational design and selection of sample preparation methods and internal standards for global metabolomics. PMID:28000704

Molecularly imprinted polymer for selective extraction of malachite green from seawater and seafood coupled with high-performance liquid chromatographic determination.

PubMed

Lian, Ziru; Wang, Jiangtao

2012-12-01

In this paper, a highly selective sample cleanup procedure combining molecular imprinting technique (MIT) and solid-phase extraction (SPE) was developed for the isolation of malachite green in seawater and seafood samples. The molecularly imprinted polymer (MIP) was prepared using malachite green as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The imprinted polymer and non-imprinted polymer were characterized by scanning electron microscope and static adsorption experiments. The MIP showed a high adsorption capacity and was used as selective sorbent for the SPE of malachite green. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chromatography with diodearray detection for the analysis of malachite green in seawater and seafood samples was also established. Finally, five samples were determined. The results showed that malachite green concentration in one seawater sample was at 1.30 μg L⁻¹ and the RSD (n=3) was 4.15%. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Selective extraction of halogenated compounds from data measured by comprehensive multidimensional gas chromatography/high resolution time-of-flight mass spectrometry for non-target analysis of environmental and biological samples.

PubMed

Hashimoto, Shunji; Zushi, Yasuyuki; Fushimi, Akihiro; Takazawa, Yoshikatsu; Tanabe, Kiyoshi; Shibata, Yasuyuki

2013-03-22

We developed a method that selectively extracts a subset from comprehensive 2D gas chromatography (GC×GC) and high-resolution time-of-flight mass spectrometry (HRTOFMS) data to detect and identify trace levels of organohalogens. The data were obtained by measuring several environmental and biological samples, namely fly ash, soil, sediment, the atmosphere, and human urine. For global analysis, some samples were measured without purification. By using our novel software, the mass spectra of organochlorines or organobromines were then extracted into a data subset under high mass accuracy conditions that were approximately equivalent to a mass resolution of 6000 for some samples. Mass defect filtering as pre-screening for the data extraction was very effective in removing the mass spectra of hydrocarbons. Those results showed that data obtained with HRTOFMS are valuable for global analysis of organohalogens, and probably of other compounds if specific data extraction methods can be devised. Copyright © 2013 Elsevier B.V. All rights reserved.

Method for extracting copper, silver and related metals

DOEpatents

Moyer, B.A.; McDowell, W.J.

1987-10-23

A process for selectively extracting precious metals such as silver and gold concurrent with copper extraction from aqueous solutions containing the same. The process utilizes tetrathiamacrocycles and high molecular weight organic acids that exhibit a synergistic relationship when complexing with certain metal ions thereby removing them from ore leach solutions.

Method for extracting copper, silver and related metals

DOEpatents

Moyer, Bruce A.; McDowell, W. J.

1990-01-01

A process for selectively extracting precious metals such as silver and gold concurrent with copper extraction from aqueous solutions containing the same. The process utilizes tetrathiamacrocycles and high molecular weight organic acids that exhibit a synergistic relationship when complexing with certain metal ions thereby removing them from ore leach solutions.

Molecularly imprinted polymers with synthetic dummy template for simultaneously selective removal and enrichment of ginkgolic acids from Ginkgo biloba L. leaves extracts.

PubMed

Ji, Wenhua; Ma, Xiuli; Xie, Hongkai; Chen, Lingxiao; Wang, Xiao; Zhao, Hengqiang; Huang, Luqi

2014-11-14

Dummy molecularly imprinted polymers (DMIPs) for simultaneously selective removal and enrichment of ginkgolic acids (GAs) during the processing of Ginkgo biloba leaves have been prepared. Two dummy template molecule with similar structural skeleton to GAs, 6-methoxysalicylic acid (MOSA, DT-1) and 6-hexadecyloxysalicylic acid (HOSA, DT-2), have been designed and synthesized. The performance of the DMIPs and NIPs were evaluated including selective recognition capacity, adsorption isotherm, and adsorption kinetics. The selective recognition capacity of the three GAs with four analogues on the sorbents illustrated that the DMIPs sorbents have high specificity for GAs. An efficient method based on DMIP-HOSA coupled with solid-phase extraction (SPE) was developed for simultaneously selective removal and enrichment of ginkgolic acids (GAs) during the processing of Ginkgo biloba leaves. The method showed excellent recoveries (82.5-88.7%) and precision (RSD 0.5-2.6%, n=5) for licorice extracts, Gastrodia elata extracts and pepper extracts spiked at three concentration levels each (50, 100, 200 μg mL(-1)). The results indicated that GAs and standardized Ginkgo biloba leaves extracts could be obtained simultaneously through the DMIP-SPE. Copyright © 2014 Elsevier B.V. All rights reserved.

Optimization of furfural production from D-xylose with formic acid as catalyst in a reactive extraction system.

PubMed

Yang, Wandian; Li, Pingli; Bo, Dechen; Chang, Heying; Wang, Xiaowei; Zhu, Tao

2013-04-01

Furfural is one of the most promising platform chemicals derived from biomass. In this study, response surface methodology (RSM) was utilized to determine four important parameters including reaction temperature (170-210°C), formic acid concentration (5-25 g/L), o-nitrotoluene volume percentage (20-80 vt.%), and residence time (40-200 min). The maximum furfural yield of 74% and selectivity of 86% were achieved at 190°C for 20 g/L formic acid concentration and 75 vt.% o-nitrotoluene by 75 min. The high boiling solvent, o-nitrotoluene, was recommended as extraction solvent in a reactive extraction system to obtain high furfural yield and reduce furfural-solvent separation costs. Although the addition of halides to the xylose solutions enhanced the furfural yield and selectivity, the concentration of halides was not an important factor on the furfural yield and selectivity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Iris recognition based on key image feature extraction.

PubMed

Ren, X; Tian, Q; Zhang, J; Wu, S; Zeng, Y

2008-01-01

In iris recognition, feature extraction can be influenced by factors such as illumination and contrast, and thus the features extracted may be unreliable, which can cause a high rate of false results in iris pattern recognition. In order to obtain stable features, an algorithm was proposed in this paper to extract key features of a pattern from multiple images. The proposed algorithm built an iris feature template by extracting key features and performed iris identity enrolment. Simulation results showed that the selected key features have high recognition accuracy on the CASIA Iris Set, where both contrast and illumination variance exist.

In vitro antiprotozoan activity and mechanisms of action of selected Ghanaian medicinal plants against Trypanosoma, Leishmania, and Plasmodium parasites.

PubMed

Ohashi, Mitsuko; Amoa-Bosompem, Michael; Kwofie, Kofi Dadzie; Agyapong, Jefferey; Adegle, Richard; Sakyiamah, Maxwell Mamfe; Ayertey, Frederick; Owusu, Kofi Baffuor-Awuah; Tuffour, Isaac; Atchoglo, Philip; Tung, Nguyen Huu; Uto, Takuhiro; Aboagye, Frederick; Appiah, Alfred Ampomah; Appiah-Opong, Regina; Nyarko, Alexander K; Anyan, William Kofi; Ayi, Irene; Boakye, Daniel Adjei; Koram, Kwadwo Ansah; Edoh, Dominic; Yamaoka, Shoji; Shoyama, Yukihiro; Ohta, Nobuo

2018-05-07

Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti-Trypanosoma, anti-Leishmania, and anti-Plasmodium activities in vitro and investigated their mechanisms of action. Twenty-three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC 50 values less than 20 μg/ml. Eleven extracts showed high anti-Trypanosoma activity with Bidens pilosa whole plant and Morinda lucida leaf extracts recording the highest activities. Their IC 50 (selectivity index [SI]) values were 5.51 μg/ml (35.00) and 5.96 μg/ml (13.09), respectively. Nine extracts had high anti-Leishmania activity with Annona senegalensis and Cassia alata leaf extracts as the most active. Their IC 50 (SI) values were 10.8 μg/ml (1.50) and 10.1 μg/ml (0.37), respectively. Six extracts had high anti-Plasmodium activity with the leaf and stem-bark extracts of Terminalia ivorensis recording the highest activity. Their IC 50 (SI) values were 7.26 μg/ml (129.36) and 17.45 μg/ml (17.17), respectively. Only M. lucida at 25 μg/ml induced significant apoptosis-like cell death in Trypanosoma parasites. Anti-Leishmania active extracts induced varying morphological changes in Leishmania parasites such as multiple nuclei and/or kinetoplast, incomplete flagella division, or nuclear fragmentation. Active extracts may be potential sources for developing new chemotherapy against these infections. Copyright © 2018 John Wiley & Sons, Ltd.

Selective Extraction of Rare Earth Elements from Permanent Magnet Scraps with Membrane Solvent Extraction.

PubMed

Kim, Daejin; Powell, Lawrence E; Delmau, Lætitia H; Peterson, Eric S; Herchenroeder, Jim; Bhave, Ramesh R

2015-08-18

The rare earth elements (REEs) such as neodymium, praseodymium, and dysprosium were successfully recovered from commercial NdFeB magnets and industrial scrap magnets via membrane assisted solvent extraction (MSX). A hollow fiber membrane system was evaluated to extract REEs in a single step with the feed and strip solutions circulating continuously through the MSX system. The effects of several experimental variables on REE extraction such as flow rate, concentration of REEs in the feed solution, membrane configuration, and composition of acids were investigated with the MSX system. A multimembrane module configuration with REEs dissolved in aqueous nitric acid solutions showed high selectivity for REE extraction with no coextraction of non-REEs, whereas the use of aqueous hydrochloric acid solution resulted in coextraction of non-REEs due to the formation of chloroanions of non-REEs. The REE oxides were recovered from the strip solution through precipitation, drying, and annealing steps. The resulting REE oxides were characterized with XRD, SEM-EDX, and ICP-OES, demonstrating that the membrane assisted solvent extraction is capable of selectively recovering pure REEs from the industrial scrap magnets.

Selective determination of heavy metals (Cd, Pb, Cr) speciation forms from hortic anthrosols

NASA Astrophysics Data System (ADS)

Bulgariu, Dumitru; Bulgariu, Laura; Filipov, Feodor; Astefanei, Dan; Stoleru, Vasile

2010-05-01

In soils from glass houses, the speciation and inter-phases distribution processes of heavy metals have a particular dynamic, different in comparison with those from non-protected soils. The predominant distribution forms of heavy metals in such soils types are: complexes with low mass organic molecules, organic-mineral complexes, complexes with inorganic ligands (hydroxide-complexes, carbonate-complexes, sulphate-complexes, etc.) and basic salts. All of these have high stabilities in conditions of soils from glass houses, and in consequence, the separation and determination of speciation forms (which is directly connected with biodisponibility of heavy metals) by usual methods id very difficult and has a high uncertain degree. In this study is presented an original method for the selective separation and differentiation of speciation forms of heavy metals from glass houses soils, which is based by the combination of solid-liquid sequential extraction (SPE) with the extraction in aqueous polymer-inorganic salt two-phase systems (ABS). The soil samples used for this study have been sampled from three different locations (glass houses from Iasi, Barlad and Bacau - Romania) where the vegetables cultivation have been performed by three different technologies. In this way was estimated the applicability and the analytical limits of method proposed by as, in function of the chemical-mineralogical and physical-chemical characteristics of soils. As heavy metals have been studied cadmium, lead and chromium, all being known for their high toxicity. The procedure used for the selective separation and differentiation of speciation forms of heavy metals from glass houses soils has two main steps: (i) non-destructive separation of chemical-mineralogical associations and aggregates from soils samples - for this the separation method with heavy liquids (bromophorme) and isodynamic magnetic method have been used; (ii) sequential extraction of heavy metals from soil fractions separated in the first step, by using combined SPE-ABS procedure. For the preparation of combined extraction systems was used polyethylene glycol (with different molecular mass: 2000, 4000 and 8000). As phase-forming inorganic salts and as selective extracting agents we have used different usual inorganic reagents. The type and concentration of phase-forming salts have been selected in function of, both nature of extracted heavy metals and chemical-mineralogical characteristics of soil samples. The experimental parameters investigated in this study are: molecular mass of polyethylene glycol and the concentration of polymeric solutions, nature and concentration of phase-forming salts, nature and concentration of extracting agents, pH in extraction system phase, type of extracted heavy metals, type of speciation forms of heavy metals and their concentrations. All these factors can influence significantly the efficiency and the selectivity of separation process. The experimental results have indicate that the combined SPE-ABS extraction systems have better separation efficiency, in comparison with traditional SPE systems and ca realized a accurate discrimination between speciation forms of heavy metals from soils. Under these conditions, the estimation of inter-phases distribution and biodisponibility of heavy metals has a high precision. On the other hand, when the combined SPE-ABS systems are used, the concomitant extraction of the elements from the same geochemical association with studied heavy metals (inevitable phenomena in case of separation by SPE procedures) is significant diminished. This increases the separation selectivity and facilitated the more accurate determination of speciation forms concentration. By adequate selection of extraction conditions can be realized the selective separation of organic-mineral complexes, which will permit to perform detailed studies about the structure and chemical composition of these. Acknowledgments The authors would like to acknowledge the financial support from Romanian Ministry of Education and Research (Project PNCDI 2-D5 no. 51045/07 and project PNCDI 2 - D5 no. 52-141 / 2008).

Selective Separation and Determination of Heavy Metals (Cd, Pb, Cr) Speciation Forms from Hortic Antrosols

NASA Astrophysics Data System (ADS)

Bulgariu, D.; Bulgariu, L.

2009-04-01

The speciation, inter-phases distribution and biodisponibility of heavy metals in soils represent one of main problem of environmental geochemistry and agro-chemistry. This problem is very important in case of hortic antrosols (soils from glasshouses) for the elimination of agricultural products (fruits, vegetables) contamination with heavy metals. In soils from glass houses, the speciation and inter-phases distribution processes of heavy metals have a particular dynamic, different in comparison with those from non-protected soils. The predominant distribution forms of heavy metals in such soils types are: complexes with low mass organic molecules, organic-mineral complexes, complexes with inorganic ligands (hydroxide-complexes, carbonate-complexes, sulphate-complexes, etc.) and basic salts. All of these have high stabilities in conditions of soils from glass houses, and in consequence, the separation and determination of speciation forms (which is directly connected with biodisponibility of heavy metals) by usual methods id very difficult and has a high uncertain degree. In this study is presented an original method for the selective separation and differentiation of speciation forms of heavy metals from glass houses soils, which is based by the combination of solid-liquid sequential extraction (SPE) with the extraction in aqueous polymer-inorganic salt two-phase systems (ABS). The soil samples used for this study have been sampled from three different locations (glass houses from Iasi, Barlad and Bacau - Romania) where the vegetables cultivation have bee performed by three different technologies. In this way was estimated the applicability and the analytical limits of method proposed by as, in function of the chemical-mineralogical and physical-chemical characteristics of soils. As heavy metals have been studied cadmium, lead and chromium, all being known for their high toxicity. The procedure used for the selective separation and differentiation of speciation forms of heavy metals from glass houses soils has two main steps: (i) non-destructive separation of chemical-mineralogical associations and aggregates from soils samples - for this the separation method with heavy liquids (bromophorme) and isodynamic magnetic method have been used; (ii) sequential extraction of heavy metals from soil fractions separated in the first step, by using combined SPE-ABS procedure. For the preparation of combined extraction systems was used polyethylene glycol (with different molecular mass: 2000, 4000 and 8000). As phase-forming inorganic salts and as selective extracting agents we have used different usual inorganic reagents. The type and concentration of phase-forming salts have been selected in function of, both nature of extracted heavy metals and chemical-mineralogical characteristics of soil samples. The experimental parameters investigated in this study are: molecular mass of polyethylene glycol and the concentration of polymeric solutions, nature and concentration of phase-forming salts, nature and concentration of extracting agents, pH in extraction system phase, type of extracted heavy metals, type of speciation forms of heavy metals and their concentrations. All these factors can influence significantly the efficiency and the selectivity of separation process. The experimental results have indicate that the combined SPE-ABS extraction systems have better separation efficiency, in comparison with traditional SPE systems and ca realized a accurate discrimination between speciation forms of heavy metals from soils. Under these conditions, the estimation of inter-phases distribution and biodisponibility of heavy metals has a high precision. On the other hand, when the combined SPE-ABS systems are used, the concomitant extraction of the elements from the same geochemical association with studied heavy metals (inevitable phenomena in case of separation by SPE procedures) is significant diminished. This increases the separation selectivity and facilitated the more accurate determination of speciation forms concentration. By adequate selection of extraction conditions can be realized the selective separation of organic-mineral complexes, which will permit to perform detailed studies about the structure and chemical composition of these. Acknowledgments The authors would like to acknowledge the financial support from Romanian Ministry of Education and Research (Project PNCDI 2-D5 no. 51045/07).

Supercritical Carbon Dioxide Extraction of Selected Herbal Leaves: An Overview

NASA Astrophysics Data System (ADS)

Hamid, I. A. Abd; Ismail, N.; Rahman, N. Abd

2018-05-01

Supercritical fluid extraction of carbon dioxide (SC-CO2) is one of new alternative extraction method that has been widely used to isolate bioactive components from variety of plant materials. The method was proved to be clean and safe, compatible for the extraction of edible products such as spices, food additives, medicines and nutritional supplement products compared to traditional extraction techniques such as solvent extraction, hydro distillation and steam distillation. The SC-CO2 extraction was known as highly influenced by its process parameter such as temperature and pressure for obtaining maximum yield. Therefore, a clear review on the optimum range of temperature and pressure for herbal leaves extraction using SC-CO2 is necessary for future reference. The aim of this work is to analyze the effect of temperature and pressure of SC-CO2 process without modifier on extraction yield of some selected herbal leaves i.e clubmoss, drumstick leaves, kratom leaves, mallee and myrtle leaves. The values of investigated parameters were; pressure from 8.9 to 50 MPa and temperature from 35 to 80°C. The results showed that the highest extraction yields were obtained when the pressure and temperature were above 30 MPa and 40°C. The interaction between pressure and temperature for SC-CO2 extraction of plant leaves are crucial since the values cannot be very high or very low in order to preserve the quality of the extracts.

Aptamer-functionalized Magnetic Conjugated Organic Frameworks for Selective Extraction of Trace Hydroxylated Polychlorinated Biphenyls in Human Serum.

PubMed

Jiang, Dandan; Hu, Tingting; Zheng, Haijiao; Xu, Guoxing; Jia, Qiong

2018-05-02

Herein, a novel solid phase extraction adsorbent based on aptamer-functionalized magnetic conjugated organic frameworks (COFs) was developed for selective extraction of trace hydroxylated polychlorinated biphenyls (OH-PCBs). The material possessed advantages of superparamagnetism of magnetic core, high surface area and porous structure of COFs, and high specific affinity of aptamer. In combination with high-performance liquid chromatography/mass spectrometry, the aptamer-functionalized magnetic COFs was used for the capture of hydroxy-2',3',4',5,5'-pentachlorobiphenyl (2-OH-CB 124) in human serum. The method provided a linear range of 0.01-40 ng mL-1 with a good correlation coefficient (R2= 0.9973). The limit of detection was found to be as low as 2.1 pg mL-1. Furthermore, the material possessed good reusability and could be applied in replicate at least for 10 extraction cycles with recoveries over 90%. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Simultaneous determination of four plant hormones in bananas by molecularly imprinted solid-phase extraction coupled with high performance liquid chromatography.

PubMed

Yan, Hongyuan; Wang, Fang; Han, Dandan; Yang, Gengliang

2012-06-21

A highly selective molecularly imprinted solid-phase extraction (MISPE) combined with liquid chromatography-ultraviolet detection was developed for the simultaneous isolation and determination of four plant hormones including indole-3-acetic acid (IAA), indole-3-propionic acid (IPA), indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA) in banana samples. The new molecularly imprinted microspheres (MIMs) prepared by aqueous suspension polymerization using 3-hydroxy-2-naphthoic acid and 1-methylpiperazine as mimic templates performed with high selectivity and affinity for the four plant hormones, and applied as selective sorbents of solid-phase extraction could effectively eliminate the interferences of the banana matrix. Good linearity was obtained in a range of 0.04-4.00 μg g(-1) and the recoveries of the four plant hormones at three spiked levels ranged from 78.5 to 107.7% with the relative standard deviations (RSD) of less than 4.6%. The developed MISPE-HPLC protocol obviously improved the selectivity and eliminated the effect of template leakage on quantitative analysis, and could be applied for the determination of plant hormones in complicated biological samples.

Acetylcholinesterase affinity-based screening assay on Lippia gracilis Schauer extracts.

PubMed

Vanzolini, K L; da F Sprenger, R; Leme, G M; de S Moraes, V R; Vilela, A F L; Cardoso, C L; Cass, Q B

2018-05-10

The use of affinity-based protein assay produced by covalently linking acetylcholinesterase to magnetic beads, followed by chemical characterization of the selective binders using Liquid Chromatography with tandem High-Resolution Mass Spectrometry (LC-HRMS) is herein described for profiling crude aqueous natural product extracts. The fishing assay was first modulated using galanthamine as a reference ligand and then, the assay condition was adjusted for the aqueous leaves extracts obtained from Lippia gracilis Schauer (genotype 201) that was used as the natural combinatory library. From the experiments, a selective binder has been undisclosed with an accurate mass of 449.1131 m/z and identified as eriodictyol 2'-O-glucoside or eriodictyol 3'-O-glucoside. The selectivity of the binding assay was demonstrated, as much as, that erydictiol 7-O-glucoside was not fished, although it was present in the crude aqueous extract. The binding assay platform exhibited high specificity and did not require any sample pretreatment, making it appropriate for profiling binders at natural libraries. Copyright © 2018 Elsevier B.V. All rights reserved.

Mixed monofunctional extractants for trivalent actinide/lanthanide separations: TALSPEAK-MME

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Aaron T.; Nash, Kenneth L.

The basic features of an f-element extraction process based on a solvent composed of equimolar mixtures of Cyanex-923 (a mixed trialkyl phosphine oxide) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) extractants in n-dodecane are investigated in this report. This system, which combines features of the TRPO and TALSPEAK processes, is based on co-extraction of trivalent lanthanides and actinides from 0.1 to 1.0 M HNO 3 followed by application of a buffered aminopolycarboxylate solution strip to accomplish a Reverse TALSPEAK selective removal of actinides. This mixed-extractant medium could enable a simplified approach to selective trivalent f-element extraction and actinide partitioning in amore » single process. As compared with other combined process applications in development for more compact actinide partitioning processes (DIAMEX-SANEX, GANEX, TRUSPEAK, ALSEP), this combination features only monofunctional extractants with high solubility limits and comparatively low molar mass. Selective actinide stripping from the loaded extractant phase is done using a glycine-buffered solution containing N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA) or triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetic acid (TTHA). Lastly, the results reported provide evidence for simplified interactions between the two extractants and demonstrate a pathway toward using mixed monofunctional extractants to separate trivalent actinides (An) from fission product lanthanides (Ln).« less

Mixed monofunctional extractants for trivalent actinide/lanthanide separations: TALSPEAK-MME

DOE PAGES

Johnson, Aaron T.; Nash, Kenneth L.

2015-08-20

The basic features of an f-element extraction process based on a solvent composed of equimolar mixtures of Cyanex-923 (a mixed trialkyl phosphine oxide) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) extractants in n-dodecane are investigated in this report. This system, which combines features of the TRPO and TALSPEAK processes, is based on co-extraction of trivalent lanthanides and actinides from 0.1 to 1.0 M HNO 3 followed by application of a buffered aminopolycarboxylate solution strip to accomplish a Reverse TALSPEAK selective removal of actinides. This mixed-extractant medium could enable a simplified approach to selective trivalent f-element extraction and actinide partitioning in amore » single process. As compared with other combined process applications in development for more compact actinide partitioning processes (DIAMEX-SANEX, GANEX, TRUSPEAK, ALSEP), this combination features only monofunctional extractants with high solubility limits and comparatively low molar mass. Selective actinide stripping from the loaded extractant phase is done using a glycine-buffered solution containing N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA) or triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetic acid (TTHA). Lastly, the results reported provide evidence for simplified interactions between the two extractants and demonstrate a pathway toward using mixed monofunctional extractants to separate trivalent actinides (An) from fission product lanthanides (Ln).« less

Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds

PubMed Central

Poojary, Mahesha M.; Barba, Francisco J.; Aliakbarian, Bahar; Donsì, Francesco; Pataro, Gianpiero; Dias, Daniel A.; Juliano, Pablo

2016-01-01

Marine microalgae and seaweeds (microalgae) represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield), selectivity (purity), high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability. PMID:27879659

Innovative Alternative Technologies to Extract Carotenoids from Microalgae and Seaweeds.

PubMed

Poojary, Mahesha M; Barba, Francisco J; Aliakbarian, Bahar; Donsì, Francesco; Pataro, Gianpiero; Dias, Daniel A; Juliano, Pablo

2016-11-22

Marine microalgae and seaweeds (microalgae) represent a sustainable source of various bioactive natural carotenoids, including β-carotene, lutein, astaxanthin, zeaxanthin, violaxanthin and fucoxanthin. Recently, the large-scale production of carotenoids from algal sources has gained significant interest with respect to commercial and industrial applications for health, nutrition, and cosmetic applications. Although conventional processing technologies, based on solvent extraction, offer a simple approach to isolating carotenoids, they suffer several, inherent limitations, including low efficiency (extraction yield), selectivity (purity), high solvent consumption, and long treatment times, which have led to advancements in the search for innovative extraction technologies. This comprehensive review summarizes the recent trends in the extraction of carotenoids from microalgae and seaweeds through the assistance of different innovative techniques, such as pulsed electric fields, liquid pressurization, supercritical fluids, subcritical fluids, microwaves, ultrasounds, and high-pressure homogenization. In particular, the review critically analyzes technologies, characteristics, advantages, and shortcomings of the different innovative processes, highlighting the differences in terms of yield, selectivity, and economic and environmental sustainability.

Advances in organic-inorganic hybrid sorbents for the extraction of organic and inorganic pollutants in different types of food and environmental samples.

PubMed

Ng, Nyuk-Ting; Kamaruddin, Amirah Farhan; Wan Ibrahim, Wan Aini; Sanagi, Mohd Marsin; Abdul Keyon, Aemi S

2018-01-01

The efficiency of the extraction and removal of pollutants from food and the environment has been an important issue in analytical science. By incorporating inorganic species into an organic matrix, a new material known as an organic-inorganic hybrid material is formed. As it possesses high selectivity, permeability, and mechanical and chemical stabilities, organic-inorganic hybrid materials constitute an emerging research field and have become popular to serve as sorbents in various separaton science methods. Here, we review recent significant advances in analytical solid-phase extraction employing organic-inorganic composite/nanocomposite sorbents for the extraction of organic and inorganic pollutants from various types of food and environmental matrices. The physicochemical characteristics, extraction properties, and analytical performances of sorbents are discussed; including morphology and surface characteristics, types of functional groups, interaction mechanism, selectivity and sensitivity, accuracy, and regeneration abilities. Organic-inorganic hybrid sorbents combined with extraction techniques are highly promising for sample preparation of various food and environmental matrixes with analytes at trace levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solvent extraction: the coordination chemistry behind extractive metallurgy.

PubMed

Wilson, A Matthew; Bailey, Phillip J; Tasker, Peter A; Turkington, Jennifer R; Grant, Richard A; Love, Jason B

2014-01-07

The modes of action of the commercial solvent extractants used in extractive hydrometallurgy are classified according to whether the recovery process involves the transport of metal cations, M(n+), metalate anions, MXx(n-), or metal salts, MXx into a water-immiscible solvent. Well-established principles of coordination chemistry provide an explanation for the remarkable strengths and selectivities shown by most of these extractants. Reagents which achieve high selectivity when transporting metal cations or metal salts into a water-immiscible solvent usually operate in the inner coordination sphere of the metal and provide donor atom types or dispositions which favour the formation of particularly stable neutral complexes that have high solubility in the hydrocarbons commonly used in recovery processes. In the extraction of metalates, the structures of the neutral assemblies formed in the water-immiscible phase are usually not well defined and the cationic reagents can be assumed to operate in the outer coordination spheres. The formation of secondary bonds in the outer sphere using, for example, electrostatic or H-bonding interactions are favoured by the low polarity of the water-immiscible solvents.

Optimization of a high-pressure pore water extraction device.

PubMed

Cyr, Martin; Daidié, Alain

2007-02-01

High-pressure squeezing is a technique used for the extraction of the pore water of porous materials such as sediments, soils, rocks, and concrete. The efficiency of extraction depends on the maximum pressures on the materials. This article presents the design of a high-pressure device reaching an axial pressure of 1000 MPa which has been developed to improve the efficiency of extraction. The increase in squeezing pressure implies high stresses inside the chamber, so specialized expertise was required to design a safe, functional device that could withstand pressures significantly higher than common laboratory equipment. The design includes finite element calculations, selection of appropriate materials, and descriptive construction details for the apparatus. It also includes an experimental study of the performance of the apparatus in terms of extraction efficiency.

Optimization of an extraction protocol for organic matter from soils and sediments using high resolution mass spectrometry: selectivity and biases

NASA Astrophysics Data System (ADS)

Chu, R. K.; Tfaily, M. M.; Tolic, N.; Kyle, J. E.; Robinson, E. R.; Hess, N. J.; Paša-Tolić, L.

2015-12-01

Soil organic matter (SOM) is a complex mixture of above and belowground plant litter and microbial residues, and is a key reservoir for carbon (C) and nutrient biogeochemical cycling in different ecosystems. A limited understanding of the molecular composition of SOM prohibits the ability to routinely decipher chemical processes within soil and predict how terrestrial C fluxes will response to changing climatic conditions. Here, we present that the choice of solvent can be used to selectively extract different compositional fractions from SOM to either target a specific class of compounds or gain a better understanding of the entire composition of the soil sample using 12T Fourier transform ion cyclotron resonance mass spectrometry. Specifically, we found that hexane and chloroform were selective for lipid-like compounds with very low O:C ratios; water was selective for carbohydrates with high O:C ratios; acetonitrile preferentially extracts lignin, condensed structures, and tannin polyphenolic compounds with O:C > 0.5; methanol has higher selectivity towards lignin and lipid compounds characterized with relatively low O:C < 0.5. Hexane, chloroform, methanol, acetonitrile and water increase the number and types of organic molecules extracted from soil for a broader range of chemically diverse soil types. Since each solvent extracts a selective group of compounds, using a suite of solvents with varying polarity for analysis results in more comprehensive representation of the diversity of organic molecules present in soil and a better representation of the whole spectrum of available substrates for microorganisms. Moreover, we have developed a sequential extraction protocol that permits sampling diverse classes of organic compounds while minimizing ionization competition during ESI while increasing sample throughput and decreasing sample volume. This allowed us to hypothesize about possible chemical reactions relating classes of organic molecules that reflect abiotic and biotic processes impacting SOM composition.

Molecularly imprinted solid-phase extraction in the analysis of agrochemicals.

PubMed

Yi, Ling-Xiao; Fang, Rou; Chen, Guan-Hua

2013-08-01

The molecular imprinting technique is a highly predeterminative recognition technology. Molecularly imprinted polymers (MIPs) can be applied to the cleanup and preconcentration of analytes as the selective adsorbent of solid-phase extraction (SPE). In recent years, a new type of SPE has formed, molecularly imprinted polymer solid-phase extraction (MISPE), and has been widely applied to the extraction of agrochemicals. In this review, the mechanism of the molecular imprinting technique and the methodology of MIP preparations are explained. The extraction modes of MISPE, including offline and online, are discussed, and the applications of MISPE in the analysis of agrochemicals such as herbicides, fungicides and insecticides are summarized. It is concluded that MISPE is a powerful tool to selectively isolate agrochemicals from real samples with higher extraction and cleanup efficiency than commercial SPE and that it has great potential for broad applications.

Quick and selective extraction of Z-ligustilide from Angelica sinensis using magnetic multiwalled carbon nanotubes.

PubMed

Zeng, Qiong; Jia, Yan-Wei; Xu, Pei-Li; Xiao, Meng-Wei; Liu, Yi-Ming; Peng, Shu-Lin; Liao, Xun

2015-12-01

A facile and highly efficient magnetic solid-phase extraction method has been developed for Z-ligustilide, the major therapeutic agent in Angelica sinensis. The solid-phase adsorbent material used was prepared by conjugating carbon nanotubes with magnetic Fe3 O4 nanoparticles via a hydrothermal reaction. The magnetic material showed a high affinity toward Z-ligustilide due to the π-π stacking interaction between the carbon nanotubes and Z-ligustilide, allowing a quick and selective exaction of Z-ligustilide from complex sample matrices. Factors influencing the magnetic solid-phase extraction such as the amount of the added adsorbent, adsorption and desorption time, and desorption solvent, were investigated. Due to its high extraction efficiency, this method was proved highly useful for sample cleanup/enrichment in quantitative high-performance liquid chromatography analysis. The proposed method had a linear calibration curve (R(2) = 0.9983) over the concentration between 4 ng/mL and 200 μg/mL Z-ligustilide. The accuracy of the method was determined by the recovery, which was from 92.07 to 104.02%, with the relative standard deviations >4.51%. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Selective adsorption of Pb(II) from aqueous solution using porous biosilica extracted from marine diatom biomass: Properties and mechanism

NASA Astrophysics Data System (ADS)

Qi, Yarong; Wang, Jingfeng; Wang, Xin; Cheng, Jay Jiayang; Wen, Zhiyou

2017-02-01

Biosilica with a surface area of 143 m2 g-1 derived from marine diatoms was prepared using an easy two-step method involving washing with dilute acid and baking. The extracted biosilica was used to remove divalent lead ions, i.e., Pb(II), from aqueous solution. The effects on Pb(II) adsorption of initial pH, shaking speed, and adsorbent loading were investigated. The adsorption of Pb(II) in the presence of other ions was also investigated. The biosilica showed a high adsorption capacity with high selectivity for Pb(II). The experimental maximum adsorption capacity was 108.2-120.4 mg g-1 at an adsorbent loading of 1 g L-1. The adsorption process was best described by the Langmuir model. The adsorbent selectively adsorbed Pb(II) from binary ion systems in the presence of Cu(II), Cd(II), Ni(II), and Ag(I). The results of this study show that biosilica extracted from fresh marine diatoms is a more efficient and selective adsorbent for Pb(II) than other inorganic adsorbents.

Blind column selection protocol for two-dimensional high performance liquid chromatography.

PubMed

Burns, Niki K; Andrighetto, Luke M; Conlan, Xavier A; Purcell, Stuart D; Barnett, Neil W; Denning, Jacquie; Francis, Paul S; Stevenson, Paul G

2016-07-01

The selection of two orthogonal columns for two-dimensional high performance liquid chromatography (LC×LC) separation of natural product extracts can be a labour intensive and time consuming process and in many cases is an entirely trial-and-error approach. This paper introduces a blind optimisation method for column selection of a black box of constituent components. A data processing pipeline, created in the open source application OpenMS®, was developed to map the components within the mixture of equal mass across a library of HPLC columns; LC×LC separation space utilisation was compared by measuring the fractional surface coverage, fcoverage. It was found that for a test mixture from an opium poppy (Papaver somniferum) extract, the combination of diphenyl and C18 stationary phases provided a predicted fcoverage of 0.48 and was matched with an actual usage of 0.43. OpenMS®, in conjunction with algorithms designed in house, have allowed for a significantly quicker selection of two orthogonal columns, which have been optimised for a LC×LC separation of crude extractions of plant material. Copyright © 2016 Elsevier B.V. All rights reserved.

Radical scavenging activity of selected medicinal plants from Limpopo province of South Africa.

PubMed

Chauke, A M; Shai, L J; Mphahlele, P M; Mogale, M A

2012-01-01

Plants collected from Limpopo province of South Africa were investigated for their antioxidative potential using the DPPH radical scavenging assay. Acetone extracts of Flueggea virosa had the highest antioxidant activity with an IC₅₀ value of 30 µg/ml, closely matching the ascorbic acid with an IC₅₀ value of 25 µg/ml. The lowest antioxidant readings were observed with extracts of Rhynchosia venulosa (root extract) and Ficus ingens (leaf extract). Acetone extract of Bridelia virosa leaves had the highest phenolic content (156 mg GAE/g extract), while the lowest content was recorded for R. venulosa root extract and leaf extract of F. ingens (8.3 and 17.7 mg GAE/g extract, respectively). There was a linear correlation between antioxidant activity and total phenolic content. Extracts with high phenolic content had low IC₅₀ values, while extracts with low phenolic concentrations had high IC₅₀ values.

Aptamer-functionalized Fe3 O4 magnetic nanoparticles as a solid-phase extraction adsorbent for the selective extraction of berberine from Cortex phellodendri.

PubMed

Jiang, Ling-Feng; Chen, Bo-Cheng; Chen, Ben; Li, Xue-Jian; Liao, Hai-Lin; Zhang, Wen-Yan; Wu, Lin

2017-07-01

The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe 3 O 4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri, but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid-phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer-functionalized Fe 3 O 4 magnetic nanoparticles, extraction time, temperature, pH value, Mg 2+ concentration, elution time and solvent were optimized for the solid-phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer-functionalized Fe 3 O 4 magnetic nanoparticles-based solid-phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid-phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Extraction of domoic acid from seawater and urine using a resin based on 2-(trifluoromethyl)acrylic acid.

PubMed

Piletska, Elena V; Villoslada, Fernando Navarro; Chianella, Iva; Bossi, Alessandra; Karim, Kal; Whitcombe, Michael J; Piletsky, Sergey A; Doucette, Gregory J; Ramsdell, John S

2008-03-03

A new solid-phase extraction (SPE) matrix with high affinity for the neurotoxin domoic acid (DA) was designed and tested. A computational modelling study led to the selection of 2-(trifluoromethyl)acrylic acid (TFMAA) as a functional monomer capable of imparting affinity towards domoic acid. Polymeric adsorbents containing TFMAA were synthesised and tested in high ionic strength solutions such as urine and seawater. The TFMAA-based polymers demonstrated excellent performance in solid-phase extraction of domoic acid, retaining the toxin while salts and other interfering compounds such as aspartic and glutamic acids were removed by washing and selective elution. It was shown that the TFMAA-based polymer provided the level of purification of domoic acid from urine and seawater acceptable for its quantification by high performance liquid chromatography-mass spectrometry (HPLC-MS) and enzyme-linked immunosorbent assay (ELISA) without any additional pre-concentration and purification steps.

Highly Selective and Considerable Subcritical Butane Extraction to Separate Abamectin in Green Tea.

PubMed

Zhang, Yating; Gu, Lingbiao; Wang, Fei; Kong, Lingjun; Pang, Huili; Qin, Guangyong

2017-06-01

We specially carried out the subcritical butane extraction to separate abamectin from tea leaves. Four parameters, such as extraction temperature, extraction time, number of extraction cycles, and solid-liquid ratio were studied and optimized through the response surface methodology with design matrix developed by Box-Behnken. Seventeen experiments with three various factors and three variable levels were employed to investigate the effect of these parameters on the extraction of abamectin. Besides, catechins, theanine, caffeine, and aroma components were determined by both high-performance liquid chromatography and gas chromatography-mass spectrometry to evaluate the tea quality before and after the extraction. The results showed that the extraction temperature was the uppermost parameter compared with others. The optimal extraction conditions selected as follows: extraction temperature, 42°C; number of extraction cycles and extraction time, 1 and 30 min, respectively; and solid-liquid ratio, 1:10. Based on the above study, the separation efficiency of abamectin was up to 93.95%. It is notable that there has a quite low loss rate, including the negligible damage of aroma components, the bits reduce of catechins within the range of 0.7%-13.1%, and a handful lessen of caffeine and theanine of 1.81% and 2.6%, respectively. The proposed method suggested subcritical butane possesses solubility for lipid-soluble pesticides, and since most of the pesticides are attached to the surfaces of tea, thus the as-applied method was successfully effective to separate abamectin because of the so practical and promising method.

Identification of COX inhibitors in the hexane extract of Japanese horse chestnut (Aesculus turbinata) seeds.

PubMed

Sato, Itaru; Kofujita, Hisayoshi; Tsuda, Shuji

2007-07-01

Japanese horse chestnut (Aesculus turbinata) seed extract inhibits the activity of cyclooxygenase (COX), but its active constituents have not been identified. In the present study, COX inhibitors were isolated from the hexane extract of this seed by means of 4 steps of liquid chromatography and were identified by gas chromatography/mass spectrometry and nuclear magnetic resonance. The COX inhibitors in the extract of Japanese horse chestnut seeds were identified as linoleic acid, linolenic acid, and oleic acid. Their efficacies were in the following order: linolenic acid = linoleic acid > oleic acid. These active constituents are C18 unsaturated fatty acids; stearic acid, a C18 saturated fatty acid, had no activity. Linolenic acid and linoleic acid had high selectivity toward COX-2 (selectivity index = 10), whereas oleic acid had no selectivity. Considering the efficacy and yield of each fatty acid, linoleic acid may be the principal COX inhibitor in this seed.

A biotin-conjugated pyridine-based isatoic anhydride, a selective room temperature RNA-acylating agent for the nucleic acid separation.

PubMed

Ursuegui, S; Yougnia, R; Moutin, S; Burr, A; Fossey, C; Cailly, T; Laayoun, A; Laurent, A; Fabis, F

2015-03-28

Isatoic anhydride derivatives, including a biotin and a disulfide linker were specifically designed for nucleic acid separation. 2'-OH selective RNA acylation, capture of biotinylated RNA adducts by streptavidin-coated magnetic beads and disulfide chemical cleavage led to isolation of highly enriched RNA samples from an initial 9/1 DNA-RNA mixture. Starting from the parent compound N-methylisatoic anhydride A which was used at 65 °C, we improved the extraction process by designing a new generation of isatoic anhydrides that are able to react under smoother conditions. Among them, a pyridine-based isatoic anhydride derivative 15f was found to be reactive at room temperature, leading to enhance the efficiency and selectivity of the extraction process by significantly reducing DNA side extraction. The extracted and purified RNAs can then be detected by RT-PCR.

Determination of selected neurotoxic insecticides in small amounts of animal tissue utilizing a newly constructed mini-extractor.

PubMed

Seifertová, Marta; Čechová, Eliška; Llansola, Marta; Felipo, Vicente; Vykoukalová, Martina; Kočan, Anton

2017-10-01

We developed a simple analytical method for the simultaneous determination of representatives of various groups of neurotoxic insecticides (carbaryl, chlorpyrifos, cypermethrin, and α-endosulfan and β-endosulfan and their metabolite endosulfan sulfate) in limited amounts of animal tissues containing different amounts of lipids. Selected tissues (rodent fat, liver, and brain) were extracted in a special in-house-designed mini-extractor constructed on the basis of the Soxhlet and Twisselmann extractors. A dried tissue sample placed in a small cartridge was extracted, while the nascent extract was simultaneously filtered through a layer of sodium sulfate. The extraction was followed by combined clean-up, including gel permeation chromatography (in case of high lipid content), ultrasonication, and solid-phase extraction chromatography using C 18 on silica and aluminum oxide. Gas chromatography coupled with high-resolution mass spectrometry was used for analyte separation, detection, and quantification. Average recoveries for individual insecticides ranged from 82 to 111%. Expanded measurement uncertainties were generally lower than 35%. The developed method was successfully applied to rat tissue samples obtained from an animal model dealing with insecticide exposure during brain development. This method may also be applied to the analytical treatment of small amounts of various types of animal and human tissue samples. A significant advantage achieved using this method is high sample throughput due to the simultaneous treatment of many samples. Graphical abstract Optimized workflow for the determination of selected insecticides in small amounts of animal tissue including newly developed mini-extractor.

Selective Extraction of Rare Earth Elements from Permanent Magnet Scraps with Membrane Solvent Extraction

DOE PAGES

Kim, Daejin; Powell, Lawrence E.; Delmau, Lætitia H.; ...

2015-06-24

In this paper, the rare earth elements (REEs) such as neodymium, praseodymium, and dysprosium were successfully recovered from commercial NdFeB magnets and industrial scrap magnets via membrane assisted solvent extraction (MSX). A hollow fiber membrane system was evaluated to extract REEs in a single step with the feed and strip solutions circulating continuously through the MSX system. The effects of several experimental variables on REE extraction such as flow rate, concentration of REEs in the feed solution, membrane configuration, and composition of acids were investigated with the MSX system. A multimembrane module configuration with REEs dissolved in aqueous nitric acidmore » solutions showed high selectivity for REE extraction with no coextraction of non-REEs, whereas the use of aqueous hydrochloric acid solution resulted in coextraction of non-REEs due to the formation of chloroanions of non-REEs. The REE oxides were recovered from the strip solution through precipitation, drying, and annealing steps. Finally, the resulting REE oxides were characterized with XRD, SEM-EDX, and ICP-OES, demonstrating that the membrane assisted solvent extraction is capable of selectively recovering pure REEs from the industrial scrap magnets.« less

Preparation of High Purity, High Molecular-Weight Chitin from Ionic Liquids for Use as an Adsorbate for the Extraction of Uranium from Seawater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rogers, Robin

Ensuring a domestic supply of uranium is a key issue facing the wider implementation of nuclear power. Uranium is mostly mined in Kazakhstan, Australia, and Canada, and there are few high-grade uranium reserves left worldwide. Therefore, one of the most appealing potential sources of uranium is the vast quantity dissolved in the oceans (estimated to be 4.4 billion tons worldwide). There have been research efforts centered on finding a means to extract uranium from seawater for decades, but so far none have resulted in an economically viable product, due in part to the fact that the materials that have beenmore » successfully demonstrated to date are too costly (in terms of money and energy) to produce on the necessary scale. Ionic Liquids (salts which melt below 100{degrees}C) can completely dissolve raw crustacean shells, leading to recovery of a high purity, high molecular weight chitin powder and to fibers and films which can be spun directly from the extract solution suggesting that continuous processing might be feasible. The work proposed here will utilize the unprecedented control this makes possible over the chitin fiber a) to prepare electrospun nanofibers of very high surface area and in specific architectures, b) to modify the fiber surfaces chemically with selective extractant capacity, and c) to demonstrate their utility in the direct extraction and recovery of uranium from seawater. This approach will 1) provide direct extraction of chitin from shellfish waste thus saving energy over the current industrial process for obtaining chitin; 2) allow continuous processing of nanofibers for very high surface area fibers in an economical operation; 3) provide a unique high molecular weight chitin not available from the current industrial process, leading to stronger, more durable fibers; and 4) allow easy chemical modification of the large surface areas of the fibers for appending uranyl selective functionality providing selectivity and ease of stripping. The resulting sorbent should prove economically feasible, as well as providing an overall net energy gain.« less

Design and fabrication of SiO2/TiO2 and MgO/TiO2 based high selective optical filters for diffuse reflectance and fluorescence signals extraction.

PubMed

Pimenta, S; Cardoso, S; Miranda, A; De Beule, P; Castanheira, E M S; Minas, G

2015-08-01

This paper presents the design, optimization and fabrication of 16 MgO/TiO2 and SiO2/TiO2 based high selective narrow bandpass optical filters. Their performance to extract diffuse reflectance and fluorescence signals from gastrointestinal tissue phantoms was successfully evaluated. The obtained results prove their feasibility to correctly extract those spectroscopic signals, through a Spearman's rank correlation test (Spearman's correlation coefficient higher than 0.981) performed between the original spectra and the ones obtained using those 16 fabricated optical filters. These results are an important step for the implementation of a miniaturized, low-cost and minimal invasive microsystem that could help in the detection of gastrointestinal dysplasia.

Attention-Based Recurrent Temporal Restricted Boltzmann Machine for Radar High Resolution Range Profile Sequence Recognition.

PubMed

Zhang, Yifan; Gao, Xunzhang; Peng, Xuan; Ye, Jiaqi; Li, Xiang

2018-05-16

The High Resolution Range Profile (HRRP) recognition has attracted great concern in the field of Radar Automatic Target Recognition (RATR). However, traditional HRRP recognition methods failed to model high dimensional sequential data efficiently and have a poor anti-noise ability. To deal with these problems, a novel stochastic neural network model named Attention-based Recurrent Temporal Restricted Boltzmann Machine (ARTRBM) is proposed in this paper. RTRBM is utilized to extract discriminative features and the attention mechanism is adopted to select major features. RTRBM is efficient to model high dimensional HRRP sequences because it can extract the information of temporal and spatial correlation between adjacent HRRPs. The attention mechanism is used in sequential data recognition tasks including machine translation and relation classification, which makes the model pay more attention to the major features of recognition. Therefore, the combination of RTRBM and the attention mechanism makes our model effective for extracting more internal related features and choose the important parts of the extracted features. Additionally, the model performs well with the noise corrupted HRRP data. Experimental results on the Moving and Stationary Target Acquisition and Recognition (MSTAR) dataset show that our proposed model outperforms other traditional methods, which indicates that ARTRBM extracts, selects, and utilizes the correlation information between adjacent HRRPs effectively and is suitable for high dimensional data or noise corrupted data.

Selective extraction of high-value phenolic compounds from distillation wastewater of basil (Ocimum basilicum L.) by pressurized liquid extraction.

PubMed

Pagano, Imma; Sánchez-Camargo, Andrea Del Pilar; Mendiola, Jose Antonio; Campone, Luca; Cifuentes, Alejandro; Rastrelli, Luca; Ibañez, Elena

2018-01-31

During the essential oil steam distillation from aromatic herbs, huge amounts of distillation wastewaters (DWWs) are generated. These by-products represent an exceptionally rich source of phenolic compounds such as rosmarinic acid (RA) and caffeic acid (CA). Herein, the alternative use of dried basil DWWs (dDWWs) to perform a selective extraction of RA and CA by pressurized liquid extraction (PLE) employing bio-based solvent was studied. To select the most suitable solvent for PLE, the theoretical modelling of Hansen solubility parameters (HSP) was carried out. This approach allows reducing the list of candidate to two solvents: ethanol and ethyl lactate. Due to the composition of the sample, mixtures of water with those solvents were also tested. An enriched PLE extract in RA (23.90 ± 2.06 mg/g extract) with an extraction efficiency of 75.89 ± 16.03% employing a water-ethanol mixture 25:75 (% v/v) at 50°C was obtained. In the case of CA, a PLE extract with 2.42 ± 0.04 mg/g extract, having an extraction efficiency of 13.86 ± 4.96% using ethanol absolute at 50°C was achieved. DWWs are proposed as new promising sources of natural additives and/or functional ingredients for cosmetic, nutraceutical, and food applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Experimental and computational studies on molecularly imprinted solid-phase extraction for gonyautoxins 2,3 from dinoflagellate Alexandrium minutum.

PubMed

Lian, Ziru; Li, Hai-Bei; Wang, Jiangtao

2016-08-01

An innovative and effective extraction procedure based on molecularly imprinted solid-phase extraction (MISPE) was developed for the isolation of gonyautoxins 2,3 (GTX2,3) from Alexandrium minutum sample. Molecularly imprinted polymer microspheres were prepared by suspension polymerization and and were employed as sorbents for the solid-phase extraction of GTX2,3. An off-line MISPE protocol was optimized. Subsequently, the extract samples from A. minutum were analyzed. The results showed that the interference matrices in the extract were obviously cleaned up by MISPE procedures. This outcome enabled the direct extraction of GTX2,3 in A. minutum samples with extraction efficiency as high as 83 %, rather significantly, without any need for a cleanup step prior to the extraction. Furthermore, computational approach also provided direct evidences of the high selective isolation of GTX2,3 from the microalgal extracts.

Magnetic dummy molecularly imprinted polymers based on multi-walled carbon nanotubes for rapid selective solid-phase extraction of 4-nonylphenol in aqueous samples.

PubMed

Rao, Wei; Cai, Rong; Yin, Yuli; Long, Fang; Zhang, Zhaohui

2014-10-01

In this paper, a highly selective sample clean-up procedure combining magnetic dummy molecular imprinting with solid-phase extraction was developed for rapid separation and determination of 4-nonylphenol (NP) in the environmental water samples. The magnetic dummy molecularly imprinted polymers (mag-DMIPs) based on multi-walled carbon nanotubes were successfully synthesized with a surface molecular imprinting technique using 4-tert-octylphenol as the dummy template and tetraethylorthosilicate as the cross-linker. The maximum adsorption capacity of the mag-DMIPs for NP was 52.4 mg g(-1) and it took about 20 min to achieve the adsorption equilibrium. The mag-DMIPs exhibited the specific selective adsorption toward NP. Coupled with high performance liquid chromatography analysis, the mag-DMIPs were used to extract solid-phase and detect NP in real water samples successfully with the recoveries of 88.6-98.1%. Copyright © 2014 Elsevier B.V. All rights reserved.

In vitro antioxidant potential of selected aphrodisiac medicinal plants.

PubMed

Riaz, M; Shahid, M; Jamil, A; Saqib, M

2017-01-01

The present study aimed to evaluate the antioxidant activity of six selected aphrodisiac medicinal plants. Useful parts of the selected medicinal plants were collected and extracted in methanolic solvent. The antioxidant activity of selected plant extract was determined through different antioxidant assays, namely DPPH radical scavenging assay and ferric reducing antioxidant assay. Moreover, antioxidant compounds, like total phenolics and total flavonoids contents, were also determined. Results showed that Mucuna pruriens seed extract displayed high contents of phenolic compounds with total phenolic content of 683.15±4.28 mg GAE/g dry plant material while the least phenolic content was observed in Asparagus racemosus (195.5±3.02 mg GAE/g dry plant material). Highest total flavonoids content was found in Anacyclus pyrethrum roots (156.58±4.01 μg CE/g) and the least content was found in Asparagus racemosus roots. Among the studied plant extracts, the highest radical scavenging activity was shown by Mucuna pruriens seed extract (82.05±0.55%) and the least percent scavenging activity was observed in Tribulus terrestris extract (36.40±2.01%). Vitamin C was used as positive control for antioxidant assays showing 93.54±0.9% radical scavenging activity. The plant extract also exhibited a strong reducing potential against free radicals. Therefore, the present study concluded that all the studied medicinal plants possess varying concentrations of secondary active metabolites responsible for the antioxidant properties of the tested plant extracts.

Methods for the guideline-based development of quality indicators--a systematic review

PubMed Central

2012-01-01

Background Quality indicators (QIs) are used in many healthcare settings to measure, compare, and improve quality of care. For the efficient development of high-quality QIs, rigorous, approved, and evidence-based development methods are needed. Clinical practice guidelines are a suitable source to derive QIs from, but no gold standard for guideline-based QI development exists. This review aims to identify, describe, and compare methodological approaches to guideline-based QI development. Methods We systematically searched medical literature databases (Medline, EMBASE, and CINAHL) and grey literature. Two researchers selected publications reporting methodological approaches to guideline-based QI development. In order to describe and compare methodological approaches used in these publications, we extracted detailed information on common steps of guideline-based QI development (topic selection, guideline selection, extraction of recommendations, QI selection, practice test, and implementation) to predesigned extraction tables. Results From 8,697 hits in the database search and several grey literature documents, we selected 48 relevant references. The studies were of heterogeneous type and quality. We found no randomized controlled trial or other studies comparing the ability of different methodological approaches to guideline-based development to generate high-quality QIs. The relevant publications featured a wide variety of methodological approaches to guideline-based QI development, especially regarding guideline selection and extraction of recommendations. Only a few studies reported patient involvement. Conclusions Further research is needed to determine which elements of the methodological approaches identified, described, and compared in this review are best suited to constitute a gold standard for guideline-based QI development. For this research, we provide a comprehensive groundwork. PMID:22436067

A multiple kernel support vector machine scheme for feature selection and rule extraction from gene expression data of cancer tissue.

PubMed

Chen, Zhenyu; Li, Jianping; Wei, Liwei

2007-10-01

Recently, gene expression profiling using microarray techniques has been shown as a promising tool to improve the diagnosis and treatment of cancer. Gene expression data contain high level of noise and the overwhelming number of genes relative to the number of available samples. It brings out a great challenge for machine learning and statistic techniques. Support vector machine (SVM) has been successfully used to classify gene expression data of cancer tissue. In the medical field, it is crucial to deliver the user a transparent decision process. How to explain the computed solutions and present the extracted knowledge becomes a main obstacle for SVM. A multiple kernel support vector machine (MK-SVM) scheme, consisting of feature selection, rule extraction and prediction modeling is proposed to improve the explanation capacity of SVM. In this scheme, we show that the feature selection problem can be translated into an ordinary multiple parameters learning problem. And a shrinkage approach: 1-norm based linear programming is proposed to obtain the sparse parameters and the corresponding selected features. We propose a novel rule extraction approach using the information provided by the separating hyperplane and support vectors to improve the generalization capacity and comprehensibility of rules and reduce the computational complexity. Two public gene expression datasets: leukemia dataset and colon tumor dataset are used to demonstrate the performance of this approach. Using the small number of selected genes, MK-SVM achieves encouraging classification accuracy: more than 90% for both two datasets. Moreover, very simple rules with linguist labels are extracted. The rule sets have high diagnostic power because of their good classification performance.

Sensitive characterization of polyphenolic antioxidants in Polygonatum odoratum by selective solid phase extraction and high performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry.

PubMed

Hu, Xin; Zhao, Huading; Shi, Shuyun; Li, Hui; Zhou, Xiaoling; Jiao, Feipeng; Jiang, Xinyu; Peng, Dongming; Chen, Xiaoqin

2015-08-10

The complexity of natural products always leads to the co-elution of interfering compounds with bioactive compounds, which then has a detrimental effect on structural elucidation. Here, a new method, based on selective solid phase extraction combined with 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) spiking and high performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry (HPLC-DAD-QTOF-MS/MS), is described for sensitive screening, selective extraction and identification of polyphenolic antioxidants in Polygonatum odoratum. First, 25 polyphenolic antioxidants (1-25) were screened by DPPH spiking with HPLC. Second, polydopamine coated Fe3O4 microspheres (Fe3O4@PDA) were prepared to selectively extract target antioxidants with extraction efficiency from 55% to 100% when the amount of Fe3O4@PDA, extraction time, desorption solvent and time were 10mg, 20 min, acetonitrile, and 5 min. Third, 25 antioxidants (10 cinnamides and 15 homoisoflavanones) were identified by HPLC-DAD-QTOF-MS/MS. Furthermore, the DPPH scavenging activities of purified compounds (IC50, 1.6-32.8 μg/mL) validated the method. Among the identified antioxidants, four of them (12, 13, 18 and 19) were new compounds, four of them (2, 4, 8 and 14) were first obtained from family Liliaceae, five of them (1, 3, 5, 7 and 9) were first reported in genus Polygonatum, while one compound (24) was first identified in this species. The results indicated that the proposed method was an efficient and sensitive approach to explore polyphenolic antioxidants from complex natural products. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison between several techniques of olive tree bark extraction (Tunisian Chemlali variety).

PubMed

Issaoui, Aimen; Ksibi, Hatem; Ksibi, Mohamed

2017-01-01

In order to better understand the chemical composition of the olive tree bark of Tunisian chemlali variety (Olea europaea cv. 'Chemlali'), this material was extracted by different ways. Compositions of extracts were used at best-selected conditions for each technique, and characterised using HPLC, LC/MS and GC-MS techniques. Analyses are conducted to an important variety of high carbon number compounds such as aliphatic compounds as nanocosane and heptacosane, and molecules with high value added tax (VAT) which can be classified as follows: diterpenes as phytol, triterpenes as squalene and also esters as Benzyl cinnamate. Hydrodistillation at high pressure seems to be a very common method to get a wide variety of compounds, the results are better than the ones obtained using supercritical fluid extraction and solvent extraction.

PREPARATION OF HIGH PURITY UF$sub 4$

DOEpatents

Magner, J.E.; Long, R.S.; Ellis, D.A.; Grinstead, R.R.

1962-04-17

S>A process for preparing very highly pure uranous tetrafluoride from impure uranium laden solvent extraction strip solutions, ion exchange process and resin-inpulp process eluate solutions which are at least 8M in hydrochloric acid is described. The process first comprises treating any of the above-mentioned solutions with a reducing agent to reduce the uranium to the + 4 oxidation state, and then contacting the reduced solution with an extractant phase comprising about 10 to 70% of tri-butyl phosphate in an organic solvent-diluent selected from benzene, ethyl-benzene, chlorobenzene, xylene, kerosene, or the like. The uranium is extracted into the extractant phase and is subsequently precipitated by treating the extractant with an aqueous fluoride solution. The highly pure uranous tetrafluoride precipitate is separated from the phases and recovered for subsequent utilization. (AEC)

Ionic liquid-based extraction followed by graphite-furnace atomic absorption spectrometry for the determination of trace heavy metals in high-purity iron metal.

PubMed

Matsumiya, Hiroaki; Kato, Tatsuya; Hiraide, Masataka

2014-02-01

The analysis of high-purity materials for trace impurities is an important and challenging task. The present paper describes a facile and sensitive method for the determination of trace heavy metals in high-purity iron metal. Trace heavy metals in an iron sample solution were rapidly and selectively preconcentrated by the extraction into a tiny volume of an ionic liquid [1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide] for the determination by graphite-furnace atomic absorption spectrometry (GFAAS). A nitrogen-donating neutral ligand, 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ), was found to be effective in the ionic liquid-based selective extraction, allowing the nearly complete (~99.8%) elimination of the iron matrix. The combination with the optimized GFAAS was successful. The detectability reached sub-μg g(-1) levels in iron metal. The novel use of TPTZ in ionic liquid-based extraction followed by GFAAS was successfully applied to the determination of traces of Co, Ni, Cu, Cd, and Pb in certified reference materials for high-purity iron metal. © 2013 Published by Elsevier B.V.

Molecularly imprinted covalent organic polymers for the selective extraction of benzoxazole fluorescent whitening agents from food samples.

PubMed

Ding, Hui; Wang, Rongyu; Wang, Xiao; Ji, Wenhua

2018-06-21

Molecularly imprinted covalent organic polymers were constructed by an imine-linking reaction between 1,3,5-triformylphloroglucinol and 2,6-diaminopyridine and used for the selective solid-phase extraction of benzoxazole fluorescent whitening agents from food samples. Binding experiments showed that imprinting sites on molecularly imprinted polymers had higher selectivity for targets compared with those of the corresponding non-imprinted polymers. Parameters affecting the solid-phase extraction procedure were examined. Under optimal conditions, actual samples were treated and the eluent was analyzed with high-performance liquid chromatography with diode-array detection. The results showed that the established method owned the wide linearity, satisfactory detection limits and quantification limits, and acceptable recoveries. Thus, this developed method possesses the practical potential to the selectively determine benzoxazole fluorescent whitening agents in complex food samples. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Matrix effect on the determination of synthetic corticosteroids and diuretics by liquid chromatography-tandem mass spectrometry

NASA Astrophysics Data System (ADS)

Dikunets, M. A.; Appolonova, S. A.; Rodchenkov, G. M.

2009-04-01

This work presents a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) procedure for selective and reliable screening of corticosteroids and diuretics in human urine. Sample preparation included the extraction, evaporation of the organic extract under nitrogen, and solution of the dry residue. The extract was analyzed by HPLC combined with tandem mass spectrometry using electro-spraying ionization at atmospheric pressure with negative ion recording. The mass spectra of all compounds were recorded, and the characteristic ions, retention times, and detection limits were determined. The procedure was validated by evaluating the degree of the matrix suppression of ionization, extraction of analytes from human biological liquid, and the selectivity and specificity of determination.

Antiplasmodial Properties and Bioassay-Guided Fractionation of Ethyl Acetate Extracts from Carica papaya Leaves

PubMed Central

Melariri, Paula; Campbell, William; Etusim, Paschal; Smith, Peter

2011-01-01

We investigated the antiplasmodial properties of crude extracts from Carica papaya leaves to trace the activity through bioassay-guided fractionation. The greatest antiplasmodial activity was observed in the ethyl acetate crude extract. C. papaya showed a high selectivity for P. falciparum against CHO cells with a selectivity index of 249.25 and 185.37 in the chloroquine-sensitive D10 and chloroquine-resistant DD2 strains, respectively. Carica papaya ethyl acetate extract was subjected to bioassay-guided fractionation to ascertain the most active fraction, which was purified and identified using high-pressure liquid chromatography (HPLC) and GC-MS (Gas chromatography-Mass spectrometry) methods. Linoleic and linolenic acids identified from the ethyl acetate fraction showed IC50 of 6.88 μg/ml and 3.58 μg/ml, respectively. The study demonstrated greater antiplasmodial activity of the crude ethyl acetate extract of Carica papaya leaves with an IC50 of 2.96 ± 0.14 μg/ml when compared to the activity of the fractions and isolated compounds. PMID:22174990

Fabric phase sorptive extraction of selected penicillin antibiotic residues from intact milk followed by high performance liquid chromatography with diode array detection.

PubMed

Samanidou, Victoria; Michaelidou, Katia; Kabir, Abuzar; Furton, Kenneth G

2017-06-01

Fabric phase sorptive extraction (FPSE), a novel sorbent-based microextraction method, was evaluated as a simple and rapid strategy for the extraction of four penicillin antibiotic residues (benzylpenicillin, cloxacillin, dicloxacillin and oxacillin) from cows' milk, without prior protein precipitation. Time-consuming solvent evaporation and reconstitution steps were eliminated successfully from the sample preparation workflow. FPSE utilizes a flexible fabric substrate, chemically coated with sol-gel derived, highly efficient, organic-inorganic hybrid sorbent as the extraction medium. Herein short-chain poly(ethylene glycol) provided optimum extraction sensitivity for the selected penicillins, which were analysed using an RP-HPLC method, validated according to the European Decision 657/2002/EC. The limit of quantitation was 10μg/kg for benzylpenicillin, 20μg/kg for cloxacillin, 25μg/kg dicloxacillin and 30μg/kg oxacillin. These are a similar order of magnitude with those reported in the literature and (with the exception of benzylpenicillin) are less than the maximum residue limits (MRL) set by European legislation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Efficient Separation and Extraction of Vanadium and Chromium in High Chromium Vanadium Slag by Selective Two-Stage Roasting-Leaching

NASA Astrophysics Data System (ADS)

Wen, Jing; Jiang, Tao; Xu, Yingzhe; Liu, Jiayi; Xue, Xiangxin

2018-06-01

Vanadium and chromium are important rare metals, leading to a focus on high chromium vanadium slag (HCVS) as a potential raw material to extract vanadium and chromium in China. In this work, a novel method based on selective two-stage roasting-leaching was proposed to separate and extract vanadium and chromium efficiently in HCVS. XRD, FT-IR, and SEM were utilized to analyze the phase evolutions and microstructure during the whole process. Calcification roasting, which can calcify vanadium selectively using thermodynamics, was carried out in the first roasting stage to transfer vanadium into acid-soluble vanadate and leave chromium in the leaching residue as (Fe0.6Cr0.4)2O3 after H2SO4 leaching. When HCVS and CaO were mixed in the molar ratio CaO/V2O3 (n(CaO)/n(V2O3)) of 0.5 to 1.25, around 90 pct vanadium and less than 1 pct chromium were extracted in the first leaching liquid, thus achieving the separation of vanadium and chromium. In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal conditions. The total vanadium and chromium leaching rates were above 95 pct, achieving the efficient separation and extraction of vanadium and chromium. The established method provides a new technique to separate vanadium and chromium during roasting rather than in the liquid form, which is useful for the comprehensive application of HCVS.

Efficient Separation and Extraction of Vanadium and Chromium in High Chromium Vanadium Slag by Selective Two-Stage Roasting-Leaching

NASA Astrophysics Data System (ADS)

Wen, Jing; Jiang, Tao; Xu, Yingzhe; Liu, Jiayi; Xue, Xiangxin

2018-04-01

Vanadium and chromium are important rare metals, leading to a focus on high chromium vanadium slag (HCVS) as a potential raw material to extract vanadium and chromium in China. In this work, a novel method based on selective two-stage roasting-leaching was proposed to separate and extract vanadium and chromium efficiently in HCVS. XRD, FT-IR, and SEM were utilized to analyze the phase evolutions and microstructure during the whole process. Calcification roasting, which can calcify vanadium selectively using thermodynamics, was carried out in the first roasting stage to transfer vanadium into acid-soluble vanadate and leave chromium in the leaching residue as (Fe0.6Cr0.4)2O3 after H2SO4 leaching. When HCVS and CaO were mixed in the molar ratio CaO/V2O3 (n(CaO)/n(V2O3)) of 0.5 to 1.25, around 90 pct vanadium and less than 1 pct chromium were extracted in the first leaching liquid, thus achieving the separation of vanadium and chromium. In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal conditions. The total vanadium and chromium leaching rates were above 95 pct, achieving the efficient separation and extraction of vanadium and chromium. The established method provides a new technique to separate vanadium and chromium during roasting rather than in the liquid form, which is useful for the comprehensive application of HCVS.

Laser ion source for multi-nucleon transfer reaction products

NASA Astrophysics Data System (ADS)

Hirayama, Y.; Watanabe, Y. X.; Imai, N.; Ishiyama, H.; Jeong, S. C.; Miyatake, H.; Oyaizu, M.; Kimura, S.; Mukai, M.; Kim, Y. H.; Sonoda, T.; Wada, M.; Huyse, M.; Kudryavtsev, Yu.; Van Duppen, P.

2015-06-01

We have developed a laser ion source for the target-like fragments (TLFs) produced in multi-nucleon transfer (MNT) reactions. The operation principle of the source is based on the in-gas laser ionization and spectroscopy (IGLIS) approach. In the source TLFs are thermalized and neutralized in high pressure and high purity argon gas, and are extracted after being selectively re-ionized in a multi-step laser resonance ionization process. The laser ion source has been implemented at the KEK Isotope Separation System (KISS) for β-decay spectroscopy of neutron-rich isotopes with N = 126 of nuclear astrophysical interest. The simulations of gas flow and ion-beam optics have been performed to optimize the gas cell for efficient thermalization and fast transporting the TLFs, and the mass-separator for efficient transport with high mass-resolving power, respectively. To confirm the performances expected at the design stage, off-line experiments have been performed by using 56Fe atoms evaporated from a filament in the gas cell. The gas-transport time of 230 ms in the argon cell and the measured KISS mass-resolving power of 900 are consistent with the designed values. The high purity of the gas-cell system, which is extremely important for efficient and highly-selective production of laser ions, was achieved and confirmed from the mass distribution of the extracted ions. After the off-line tests, on-line experiments were conducted by directly injecting energetic 56Fe beam into the gas cell. After thermalization of the injected 56Fe beam, laser-produced singly-charged 56Fe+ ions were extracted. The extraction efficiency and selectivity of the gas cell in the presence of plasma induced by 56Fe beam injection as well as the time profile of the extracted ions were investigated; extraction efficiency of 0.25%, a beam purity of >99% and an extraction time of 270 ms. It has been confirmed that the performance of the KISS laser ion source is satisfactory to start the measurements of lifetimes of the β-decayed nuclei with N = 126 .

A new strategy for accelerated extraction of target compounds using molecularly imprinted polymer particles embedded in a paper-based disk.

PubMed

Zarejousheghani, Mashaalah; Schrader, Steffi; Möder, Monika; Schmidt, Matthias; Borsdorf, Helko

2018-03-01

In this study, a general simple and inexpensive method is introduced for the preparation of a paper-based selective disk-type solid phase extraction (SPE) technique, appropriate for fast and high throughput monitoring of target compounds. An ion exchange molecularly imprinted polymer (MIP) was synthesized for the extraction and analysis of acesulfame, an anthropogenic water quality marker. Acesulfame imprinting was used as an example for demonstrating the benefits of a nanosized, swellable MIP extraction sorbents integrated in an on-site compatible concept for water quality monitoring. Compared with an 8 mL standard SPE cartridge, the paper-based MIP disk (47 mm ø) format allowed (1) high sample flow rates up to 30 mL•min -1 without losing extraction efficiency (2) extracting sample volumes up to 500 mL in much shorter times than with standard SPE, (3) the reuse of the disks (up to 3 times more than SPE cartridge) due to high robustness and an efficient post-cleaning, and (4) reducing the sampling time from 100 minutes (using the standard SPE format) to about 2 minutes with the MIP paper disk for 50 mL water sample. Different parameters like cellulose fiber/polymer ratios, sample volume, sample flow-rate, washing, and elution conditions were evaluated and optimized. Using developed extraction technique with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) analysis, a new protocol was established that provides detection and quantification limits of 0.015 μg•L -1 and 0.05 μg•L -1 , respectively. The developed paper disks were used in-field for the selective extraction of target compounds and transferred to the laboratory for further analysis. Copyright © 2017 John Wiley & Sons, Ltd.

High-mesembrine Sceletium extract (Trimesemine™) is a monoamine releasing agent, rather than only a selective serotonin reuptake inhibitor.

PubMed

Coetzee, Dirk D; López, Víctor; Smith, Carine

2016-01-11

Extracts from and alkaloids contained in plants in the genus Sceletium have been reported to inhibit ligand binding to serotonin transporter. From this, the conclusion was made that Sceletium products act as selective serotonin-reuptake inhibitors. However, other mechanisms which may similarly result in the anxiolytic or anti-depressant effect ascribed to Sceletium, such as monoamine release, have not been investigated. The current study investigated simultaneously and at two consecutive time points, the effect of high-mesembrine Sceletium extract on both monoamine release and serotonin reuptake into both human astrocytes and mouse hippocampal neurons, as well as potential inhibitory effects on relevant enzyme activities. Human astrocytes and mouse hippocampal cells were treated with citalopram or Sceletium extract for 15 and 30min, after which protein expression levels of serotonin transporter (SERT) and vesicular monoamine transporter-2 (VAMT-2) was assessed using fluorescent immunocytochemistry and digital image analysis. Efficacy of inhibition of acetylcholinesterase (AChE) and monoamine oxidate-A (MAO-A) activity were assessed using the Ellman and Olsen methods (and appropriate controls) respectively. We report the first investigation of mechanism of action of Sceletium extract in the context of serotonin transport, release and reuptake in a cellular model. Cell viability was not affected by Sceletium treatment. High-mesembrine Sceletium extract down-regulated SERT expression similarly to citalopram. In addition, VMAT-2 was upregulated significantly in response to Sceletium treatment. The extract showed only relatively mild inhibition of AChE and MAO-A. We conclude that the serotonin reuptake inhibition activity ascribed to the Sceletium plant, is a secondary function to the monoamine-releasing activity of high-mesembrine Sceletium extract (Trimesemine(TM)). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A highly selective dispersive liquid-liquid microextraction approach based on the unique fluorous affinity for the extraction and detection of per- and polyfluoroalkyl substances coupled with high performance liquid chromatography tandem-mass spectrometry.

PubMed

Wang, Juan; Shi, Yali; Cai, Yaqi

2018-04-06

In the present study, a highly selective fluorous affinity-based dispersive liquid-liquid microextraction (DLLME) technique was developed for the extraction and analysis of per- and polyfluoroalkyl substances (PFASs) followed by high performance liquid chromatography tandem-mass spectrometry. Perfluoro-tert-butanol with multiple C-F bonds was chosen as the extraction solvent, which was injected into the aqueous samples with a dispersive solvent (acetonitrile) in a 120:800 (μL, v/v) mixture for PFASs enrichment. The fluorous affinity-based extraction mechanism was confirmed by the significantly higher extraction recoveries for PFASs containing multiple fluorine atoms than those for compounds with fewer or no fluorine atoms. The extraction recoveries of medium and long-chain PFASs (CF 2  > 5) exceeded 70%, except perfluoroheptanoic acid, while those of short-chain PFASs were lower than 50%, implying that the proposed DLLME may not be suitable for their extraction due to weak fluorous affinity. This highly fluoroselective DLLME technique can greatly decrease the matrix effect that occurs in mass spectrometry detection when applied to the analysis of urine samples. Under the optimum conditions, the relative recoveries of PFASs with CF 2  > 5 ranged from 80.6-121.4% for tap water, river water and urine samples spiked with concentrations of 10, 50 and 100 ng/L. The method limits of quantification for PFASs in water and urine samples were in the range of 0.6-8.7 ng/L. Furthermore, comparable concentrations of PFASs were obtained via DLLME and solid-phase extraction, confirming that the developed DLLME technique is a promising method for the extraction of PFASs in real samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Separation of Long-Lived Fission Products Tc-99 and I-129 from Synthetic Effluents by Crown Ethers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paviet-Hartmann, P.; Hartmann, T.

2006-07-01

To minimize significantly the radio-toxic inventory of nuclear geological repositories to come as well as to reduce the potential of radionuclides migration and to minimize long-term exposure, the concept of partitioning and transmutation (P/T) of nuclear waste is currently discussed. Transmutation offers the possibility to convert radio-toxic radionuclides with long half-lives into radionuclides of shorter half-lives, less toxic isotopes, or even into stable isotopes. Besides the most prominent isotopes of neptunium, plutonium, americium, and curium, the long-lived fission products Tc-99 and I-129 (half-lives of 2.13 x 10{sup 5} years, and 1.57 x 10{sup 7} years, respectively) are promising candidates formore » transmutation in order to prevent their migration from a nuclear repository. Partitioning and transmutation of the most radio-toxic radionuclides will not only minimize the nuclear waste load but most importantly will significantly reduce the long-term radio-toxic hazard of nuclear waste repositories to come. Prior to the deployment of partitioning and transmutation, selective extraction techniques are required to separate the radionuclides of concern. Since the discovery of crown ethers by C. Pedersen, various applications of crown ethers have drawn much attention. Although liquid-liquid extraction of alkali and alkali earth metals by crown ethers has been extensively studied, little data is available on the extraction of Tc-99 and I-129 by crown ethers. The methods developed herein for the specific extraction of Tc-99 and I-129 provide recommendations in support of their selectively extraction from liquid radioactive waste streams, mainly ILW. We report data on the solvent extraction of Tc-99 and I-129 from synthetic effluents by six crown ethers of varying cavity dimensions and derivatization. To satisfy the needs of new extractant systems we are demonstrating that crown ether (CE) based systems have the potential to serve as selective extractants for the separation of these long lived radionuclides from high level nuclear waste (HLW), intermediate level nuclear waste (ILW), and low level nuclear waste (LLW) streams. The experimental results show that dibenzo-18-crown-6 (DB 18C6) is highly selective towards Tc-99, and dicyclohexano-18-crown-6 (DC18C6) is highly selective towards I-129. The nature of the diluent was examined and was shown to be the most influential variable in controlling the extraction coefficients of Tc-99 and I-129. Therefore the addition of polar diluent acetone to non-polar diluent toluene enhanced the distribution coefficient of Tc-99 (DTc) was by a factor of 30. For I-129, the best extraction yield was obtained after introducing tetrachloroethane. Through the process, by a single extraction step, 85 % to 95 % of Tc-99 was extracted from synthetic effluents, while 84 % to 88 % of I-129 was extracted from different acidic media. The extraction by crown ether is a fairly rapid process and the total preparation time of the chemical separation takes about 20 minutes for a batch of eight samples. (authors)« less

Highly sensitive copper fiber-in-tube solid-phase microextraction for online selective analysis of polycyclic aromatic hydrocarbons coupled with high performance liquid chromatography.

PubMed

Sun, Min; Feng, Juanjuan; Bu, Yanan; Luo, Chuannan

2015-08-21

A fiber-in-tube solid-phase microextraction (SPME) device was developed with copper wire and copper tube, which was served as both the substrate and sorbent with high physical strength and good flexibility. Its morphology and surface properties were characterized by scanning electron microscopy and energy dispersive X-ray spectrometry. It was coupled with high performance liquid chromatography (HPLC) equipment by replacing the sample loop of six-port injection valve, building the online SPME-HPLC system conveniently. Using ten polycyclic aromatic hydrocarbons (PAHs) as model analytes, extraction conditions including sampling rate, extraction time, organic content and desorption time were investigated and optimized. The copper fiber-in-tube exhibits excellent extraction efficiency toward PAHs, with enrichment factors from 268 to 2497. The established online SPME-HPLC method provides good linearity (0.05-100μgL(-1)) and low detection limits (0.001-0.01μgL(-1)) for PAHs. It has been used to determine PAHs in water samples, with recoveries in the range of 86.2-115%. Repeatability on the same extraction tube is in the range of 0.6-3.6%, and repeatability among three tubes is in the range of 5.6-20.1%. Compared with phthalates, anilines and phenols, the copper fiber-in-tube possesses good extraction selectivity for PAHs. The extraction mechanism is probably related to hydrophobic interaction and π-electron-metal interaction. Copyright © 2015 Elsevier B.V. All rights reserved.

Determination of zearalenone and its metabolites in endometrial cancer by coupled separation techniques.

PubMed

Gadzała-Kopciuch, Renata; Cendrowski, Krzysztof; Cesarz, Anna; Kiełbasa, Paweł; Buszewski, Bogusław

2011-10-01

This study presents a selective method of isolation of zearalenone (ZON) and its metabolite, α-zearalenol (α-ZOL), in neoplastically changed human tissue by accelerated solvent and ultrasonic extractions using a mixture of acetonitrile/water (84/16% v/v) as the extraction solvent. Extraction effectiveness was determined through the selection of parameters (composition of the solvent mixture, temperature, pressure, number of cycles) with tissue contamination at the level of nanograms per gram. The produced acetonitrile/water extracts were purified, and analytes were enriched in columns packed with homemade molecularly imprinted polymers. Purified extracts were determined by liquid chromatography (LC) coupled with different detection systems (diode array detection--DAD and mass spectrometry--MS) involving the Ascentis RP-Amide as a stationary phase and gradient elution. The combination of UE-MISPE-LC (ultrasonic extraction--molecularly imprinted solid-phase extraction--liquid chromatography) produced high (R≈95-98%) and repeatable (RSD<3%) recovery values for ZON and α-ZOL. © The Author(s) 2011. This article is published with open access at Springerlink.com

[Study on process and principle of lactose grinding modification to decrease hygroscopic of Rhodiolae Crenulatae Radix et Rhizoma extract].

PubMed

Zhang, Ding-Kun; Zhang, Fang; Lin, Jun-Zhi; Han, Li; Wu, Zhen-Feng; Yang, Ying-Guang; Yang, Ming

2014-04-01

In this paper, Rhodiolae Crenulatae Radix et Rhizoma extract,with high hygroscopic,was selected as research model, while lactose was selected as modifiers to study the effect of the grinding modification method on the hygroscopic. Subsequently, particle size distribution, scannin electron microscopy, infrared spectroscopy and surface properties were adopted for a phase analysis. The results showed that the modified extract, prepared by Rhodiolae Crenulatae Radix et Rhizoma extract grinding 5 min with the same amount of lactose UP2, which hygroscopic initial velocity, acceleration, and critical relative humidity moisture were less than that of Rhodiolae Crenulatae Radix et Rhizoma extract and the mixture dramatically. In addition, compared with the mixture, the size distribution of modified extract was much less, the microstructure was also difference, while the infrared spectroscopy and surface properties were similar with that of lactose. It is the main principle that lactose particle adhered to the surface of Rhodiolae Crenulatae Radix et Rhizoma extract after grinding mofication to decress the moisture obviously.

Ultrasound-assisted enzymatic extraction and antioxidant activity of polysaccharides from pumpkin (Cucurbita moschata).

PubMed

Wu, Hao; Zhu, Junxiang; Diao, Wenchao; Wang, Chengrong

2014-11-26

An efficient ultrasound-assisted enzymatic extraction (UAEE) of Cucurbita moschata polysaccharides (CMCP) was established and the CMCP antioxidant activities were studied. The UAEE operating parameters (extraction temperature, ultrasonic power, pH, and liquid-to-material ratio) were optimized using the central composite design (CCD) and the mass transfer kinetic study in UAEE procedure was used to select the optimal extraction time. Enzymolysis and ultrasonication that were simultaneously conducted was selected as the UAEE synergistic model and the optimum extraction conditions with a maximum polysaccharide yield of 4.33 ± 0.15% were as follows: extraction temperature, 51.5 °C; ultrasonic power, 440 W; pH, 5.0; liquid-to-material ratio, 5.70:1 mL/g; and extraction time, 20 min. Evaluation of the antioxidant activity in vitro suggested that CMCP has good potential as a natural antioxidant used in the food or medicine industry because of their high reducing power and positive radical scavenging activity for DPPH radical. Copyright © 2014 Elsevier Ltd. All rights reserved.

A novel feature extraction approach for microarray data based on multi-algorithm fusion

PubMed Central

Jiang, Zhu; Xu, Rong

2015-01-01

Feature extraction is one of the most important and effective method to reduce dimension in data mining, with emerging of high dimensional data such as microarray gene expression data. Feature extraction for gene selection, mainly serves two purposes. One is to identify certain disease-related genes. The other is to find a compact set of discriminative genes to build a pattern classifier with reduced complexity and improved generalization capabilities. Depending on the purpose of gene selection, two types of feature extraction algorithms including ranking-based feature extraction and set-based feature extraction are employed in microarray gene expression data analysis. In ranking-based feature extraction, features are evaluated on an individual basis, without considering inter-relationship between features in general, while set-based feature extraction evaluates features based on their role in a feature set by taking into account dependency between features. Just as learning methods, feature extraction has a problem in its generalization ability, which is robustness. However, the issue of robustness is often overlooked in feature extraction. In order to improve the accuracy and robustness of feature extraction for microarray data, a novel approach based on multi-algorithm fusion is proposed. By fusing different types of feature extraction algorithms to select the feature from the samples set, the proposed approach is able to improve feature extraction performance. The new approach is tested against gene expression dataset including Colon cancer data, CNS data, DLBCL data, and Leukemia data. The testing results show that the performance of this algorithm is better than existing solutions. PMID:25780277

A novel feature extraction approach for microarray data based on multi-algorithm fusion.

PubMed

Jiang, Zhu; Xu, Rong

2015-01-01

Feature extraction is one of the most important and effective method to reduce dimension in data mining, with emerging of high dimensional data such as microarray gene expression data. Feature extraction for gene selection, mainly serves two purposes. One is to identify certain disease-related genes. The other is to find a compact set of discriminative genes to build a pattern classifier with reduced complexity and improved generalization capabilities. Depending on the purpose of gene selection, two types of feature extraction algorithms including ranking-based feature extraction and set-based feature extraction are employed in microarray gene expression data analysis. In ranking-based feature extraction, features are evaluated on an individual basis, without considering inter-relationship between features in general, while set-based feature extraction evaluates features based on their role in a feature set by taking into account dependency between features. Just as learning methods, feature extraction has a problem in its generalization ability, which is robustness. However, the issue of robustness is often overlooked in feature extraction. In order to improve the accuracy and robustness of feature extraction for microarray data, a novel approach based on multi-algorithm fusion is proposed. By fusing different types of feature extraction algorithms to select the feature from the samples set, the proposed approach is able to improve feature extraction performance. The new approach is tested against gene expression dataset including Colon cancer data, CNS data, DLBCL data, and Leukemia data. The testing results show that the performance of this algorithm is better than existing solutions.

Engineering molecularly imprinted polymers (MIPs) for the selective extraction and quantification of the novel psychoactive substance (NPS) methoxphenidine and its regioisomers.

PubMed

Lowdon, J W; Alkirkit, S M O; Mewis, R E; Fulton, D; Banks, C E; Sutcliffe, O B; Peeters, M

2018-04-30

In this communication, we present the first developed Molecularly Imprinted Polymers (MIPs) for the specific detection of a New Psychoactive Substance (NPS); namely, methoxphenidine (MXP) and its regioisomers. Selectivity of the MIP towards MXP is studied by analysing mixtures and an acquired street sample with High Performance Liquid Chromatography coupled to UV detection. The study demonstrates that the engineered polymers selectively extract MXP from heterogeneous samples, which makes for a very powerful diagnostic tool that can detect traces of MXP in complicated NPS samples.

Chiral imprinted polymers as enantiospecific coatings of stir bar sorptive extraction devices.

PubMed

Gomez-Caballero, Alberto; Guerreiro, Antonio; Karim, Kal; Piletsky, Sergey; Goicolea, M Aranzazu; Barrio, Ramon J

2011-10-15

This paper reports the design of Molecularly Imprinted Polymers (MIP) with affinity towards (S)-citalopram using computational modeling for the selection of functional monomers and monomer:template ratio. Acrylamide was selected as functional monomer and the final complex functional monomer/template resulted in a 3:1 ratio. The polymer was synthesized by radical polymerization initiated by UV onto magnetic stir-bars in order to obtain a stir bar sorptive extraction (SBSE) device capable of selective enantiomeric recognition. After successful template removal, the parameters affecting the SBSE procedure (sample volume, ionic strength, extraction time and pH) were optimized for the effective rebinding of the target analyte. The resultant chirally imprinted polymer based stir-bar was able to selectively extract (S)-citalopram from a racemic mixture in an aqueous media with high specificity (specificity factor 4) between 25 and 500 μgL(-1). The MIP coated stir-bars can have significance for enantiospecific sample pre-concentration and subsequent analysis without the need for any chiral chromatographic separation. Copyright © 2011 Elsevier B.V. All rights reserved.

Optimization of Cat's Whiskers Tea (Orthosiphon stamineus) Using Supercritical Carbon Dioxide and Selective Chemotherapeutic Potential against Prostate Cancer Cells

PubMed Central

Al-Suede, Fouad Saleih R.; Khadeer Ahamed, Mohamed B.; Abdul Majid, Aman S.; Baharetha, Hussin M.; Hassan, Loiy E. A.; Kadir, Mohd Omar A.; Nassar, Zeyad D.; Abdul Majid, Amin M. S.

2014-01-01

Cat's whiskers (Orthosiphon stamineus) leaves extracts were prepared using supercritical CO2 (SC-CO2) with full factorial design to determine the optimum extraction parameters. Nine extracts were obtained by varying pressure, temperature, and time. The extracts were analysed using FTIR, UV-Vis, and GC-MS. Cytotoxicity of the extracts was evaluated on human (colorectal, breast, and prostate) cancer and normal fibroblast cells. Moderate pressure (31.1 MPa) and temperature (60°C) were recorded as optimum extraction conditions with high yield (1.74%) of the extract (B2) at 60 min extraction time. The optimized extract (B2) displayed selective cytotoxicity against prostate cancer (PC3) cells (IC50 28 µg/mL) and significant antioxidant activity (IC50 42.8 µg/mL). Elevated levels of caspases 3/7 and 9 in B2-treated PC3 cells suggest the induction of apoptosis through nuclear and mitochondrial pathways. Hoechst and rhodamine assays confirmed the nuclear condensation and disruption of mitochondrial membrane potential in the cells. B2 also demonstrated inhibitory effects on motility and colonies of PC3 cells at its subcytotoxic concentrations. It is noteworthy that B2 displayed negligible toxicity against the normal cells. Chemometric analysis revealed high content of essential oils, hydrocarbon, fatty acids, esters, and aromatic sesquiterpenes in B2. This study highlights the therapeutic potentials of SC-CO2 extract of cat's whiskers in targeting prostate carcinoma. PMID:25276215

Further evaluation of Rwandan medicinal plant extracts for their antimicrobial and antiviral activities.

PubMed

Cos, P; Hermans, N; De Bruyne, T; Apers, S; Sindambiwe, J B; Vanden Berghe, D; Pieters, L; Vlietinck, A J

2002-02-01

A total of 45 Rwandan plant extracts, belonging to 37 different plant species out of 21 families, were investigated for their antibacterial, antifungal, and antiviral properties. The plants were selected on the base of their ethnomedicinal use against infections and autoimmune diseases. From all the plant extracts tested, only Clematis hirsuta (leaves) showed a pronounced antifungal activity against Candida albicans and the dermatophytes Trichophyton rubrum, Epidermophyton floccosum, and Microsporum canis. Seven plant extracts showed a high antiviral activity against the DNA-virus Herpes simplex type 1, while five and three plant extracts were highly active against the RNA-viruses Coxsackie and Polio, respectively. Only Macaranga kilimandscharica (leaves) showed an interesting anti-measles activity, whereas Eriosema montanum (leaves) and Entada abyssinica (leaves) were highly active against Semliki forest virus. Some plant extracts showed an antibacterial activity against Gram-positive bacteria and Mycobacterium fortuitum, but none of them were active against the Gram-negative bacteria tested.

Evaluation of commercial DNA and RNA extraction methods for high-throughput sequencing of FFPE samples.

PubMed

Kresse, Stine H; Namløs, Heidi M; Lorenz, Susanne; Berner, Jeanne-Marie; Myklebost, Ola; Bjerkehagen, Bodil; Meza-Zepeda, Leonardo A

2018-01-01

Nucleic acid material of adequate quality is crucial for successful high-throughput sequencing (HTS) analysis. DNA and RNA isolated from archival FFPE material are frequently degraded and not readily amplifiable due to chemical damage introduced during fixation. To identify optimal nucleic acid extraction kits, DNA and RNA quantity, quality and performance in HTS applications were evaluated. DNA and RNA were isolated from five sarcoma archival FFPE blocks, using eight extraction protocols from seven kits from three different commercial vendors. For DNA extraction, the truXTRAC FFPE DNA kit from Covaris gave higher yields and better amplifiable DNA, but all protocols gave comparable HTS library yields using Agilent SureSelect XT and performed well in downstream variant calling. For RNA extraction, all protocols gave comparable yields and amplifiable RNA. However, for fusion gene detection using the Archer FusionPlex Sarcoma Assay, the truXTRAC FFPE RNA kit from Covaris and Agencourt FormaPure kit from Beckman Coulter showed the highest percentage of unique read-pairs, providing higher complexity of HTS data and more frequent detection of recurrent fusion genes. truXTRAC simultaneous DNA and RNA extraction gave similar outputs as individual protocols. These findings show that although successful HTS libraries could be generated in most cases, the different protocols gave variable quantity and quality for FFPE nucleic acid extraction. Selecting the optimal procedure is highly valuable and may generate results in borderline quality specimens.

Design and fabrication of SiO2/TiO2 and MgO/TiO2 based high selective optical filters for diffuse reflectance and fluorescence signals extraction

PubMed Central

Pimenta, S.; Cardoso, S.; Miranda, A.; De Beule, P.; Castanheira, E.M.S.; Minas, G.

2015-01-01

This paper presents the design, optimization and fabrication of 16 MgO/TiO2 and SiO2/TiO2 based high selective narrow bandpass optical filters. Their performance to extract diffuse reflectance and fluorescence signals from gastrointestinal tissue phantoms was successfully evaluated. The obtained results prove their feasibility to correctly extract those spectroscopic signals, through a Spearman’s rank correlation test (Spearman’s correlation coefficient higher than 0.981) performed between the original spectra and the ones obtained using those 16 fabricated optical filters. These results are an important step for the implementation of a miniaturized, low-cost and minimal invasive microsystem that could help in the detection of gastrointestinal dysplasia. PMID:26309769

Simultaneous quantification of eight organic acid components in Artemisia capillaris Thunb (Yinchen) extract using high-performance liquid chromatography coupled with diode array detection and high-resolution mass spectrometry.

PubMed

Yu, Fangjun; Qian, Hao; Zhang, Jiayu; Sun, Jie; Ma, Zhiguo

2018-04-01

We aim to determine the chemical constituents of Yinchen extract and Yinchen herbs using high-performance liquid chromatography coupled with diode array detection and high-resolution mass spectrometry. The method was developed to analyze of eight organic acid components of Yinchen extract (including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, 1,3-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid). The separation was conducted using an Agilent TC-C18 column with acetonitrile - 0.2% formic acid solution as the mobile phases under gradient elution. The analytical method was fully validated in terms of linearity, sensitivity, precision, repeatability as well as recovery, and subsequently the method was performed for the quantitative assessment of Yinchen extracts and Yinchen herbs. In addition, the changes of selected markers were studied when Yinchen herbs decocting in water and isomerization occurred between the chlorogenic acids. The proposed method enables both qualitative and quantitative analyses and could be developed as a new tool for the quality evaluation of Yinchen extract and Yinchen herbs. The changes of selected markers in water decoction process could give us some novel idea when studying the link between substances and drug efficacy. Copyright © 2017. Published by Elsevier B.V.

System for selecting relevant information for decision support.

PubMed

Kalina, Jan; Seidl, Libor; Zvára, Karel; Grünfeldová, Hana; Slovák, Dalibor; Zvárová, Jana

2013-01-01

We implemented a prototype of a decision support system called SIR which has a form of a web-based classification service for diagnostic decision support. The system has the ability to select the most relevant variables and to learn a classification rule, which is guaranteed to be suitable also for high-dimensional measurements. The classification system can be useful for clinicians in primary care to support their decision-making tasks with relevant information extracted from any available clinical study. The implemented prototype was tested on a sample of patients in a cardiological study and performs an information extraction from a high-dimensional set containing both clinical and gene expression data.

Green extraction of grape skin phenolics by using deep eutectic solvents.

PubMed

Cvjetko Bubalo, Marina; Ćurko, Natka; Tomašević, Marina; Kovačević Ganić, Karin; Radojčić Redovniković, Ivana

2016-06-01

Conventional extraction techniques for plant phenolics are usually associated with high organic solvent consumption and long extraction times. In order to establish an environmentally friendly extraction method for grape skin phenolics, deep eutectic solvents (DES) as a green alternative to conventional solvents coupled with highly efficient microwave-assisted and ultrasound-assisted extraction methods (MAE and UAE, respectively) have been considered. Initially, screening of five different DES for proposed extraction was performed and choline chloride-based DES containing oxalic acid as a hydrogen bond donor with 25% of water was selected as the most promising one, resulting in more effective extraction of grape skin phenolic compounds compared to conventional solvents. Additionally, in our study, UAE proved to be the best extraction method with extraction efficiency superior to both MAE and conventional extraction method. The knowledge acquired in this study will contribute to further DES implementation in extraction of biologically active compounds from various plant sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecularly imprinted membrane extraction combined with high-performance liquid chromatography for selective analysis of cloxacillin from shrimp samples.

PubMed

Du, Wei; Sun, Min; Guo, Pengqi; Chang, Chun; Fu, Qiang

2018-09-01

Nowadays, the abuse of antibiotics in aquaculture has generated considerable problems for food safety. Therefore, it is imperative to develop a simple and selective method for monitoring illegal use of antibiotics in aquatic products. In this study, a method combined molecularly imprinted membranes (MIMs) extraction and liquid chromatography was developed for the selective analysis of cloxacillin from shrimp samples. The MIMs was synthesized by UV photopolymerization, and characterized by scanning electron microscope, Fourier transform infrared spectra, thermo-gravimetric analysis and swelling test. The results showed that the MIMs exhibited excellent permselectivity, high adsorption capacity and fast adsorption rate for cloxacillin. Finally, the method was utilized to determine cloxacillin from shrimp samples, with good accuracies and acceptable relative standard deviation values for precision. The proposed method was a promising alternative for selective analysis of cloxacillin in shrimp samples, due to the easy-operation and excellent selectivity. Copyright © 2018. Published by Elsevier Ltd.

Modeling of the Kinetics of Supercritical Fluid Extraction of Lipids from Microalgae with Emphasis on Extract Desorption

PubMed Central

Sovová, Helena; Nobre, Beatriz P.; Palavra, António

2016-01-01

Microalgae contain valuable biologically active lipophilic substances such as omega-3 fatty acids and carotenoids. In contrast to the recovery of vegetable oils from seeds, where the extraction with supercritical CO2 is used as a mild and selective method, economically viable application of this method on similarly soluble oils from microalgae requires, in most cases, much higher pressure. This paper presents and verifies hypothesis that this difference is caused by high adsorption capacity of microalgae. Under the pressures usually applied in supercritical fluid extraction from plants, microalgae bind a large fraction of the extracted oil, while under extremely high CO2 pressures their adsorption capacity diminishes and the extraction rate depends on oil solubility in supercritical CO2. A mathematical model for the extraction from microalgae was derived and applied to literature data on the extraction kinetics in order to determine model parameters. PMID:28773546

Highly selective and efficient imprinted polymers based on carboxyl-functionalized magnetic nanoparticles for the extraction of gallic acid from pomegranate rind.

PubMed

Zhang, Junjie; Li, Benqiang; Yue, Huijuan; Wang, Jing; Zheng, Yuansuo

2018-01-01

With the combined surface imprinting technique and immobilized template strategy, molecularly imprinted magnetic nanoparticles were successfully prepared and coupled with high-performance liquid chromatography to selectively separate and determine gallic acid from the pomegranate rind. On the surface of carboxyl-functionalized magnetic nanospheres, thin imprinting shells were formed using dopamine as monomer and crosslinker. The characteristics, polymerization conditions, and adsorption performances of the resultant nanomaterials were investigated in detail. In addition of good crystallinity, satisfactory magnetism, and uniform morphology of the obtained polymers, they had rapid binding kinetics, high adsorption capacity, and favorable reusability. In the mixed solution of four hydroxybenzoic acids, the prepared nanomaterials have an excellent selectivity to gallic acid with an imprinting factor of as high as 17.5. Therefore, the polymers have great potentials in specific extraction and enrichment of gallic acid from the complex natural resources. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Review of the harvesting and extraction program within the National Alliance for Advanced Biofuels and Bioproducts

DOE PAGES

Marrone, Babetta L.; Lacey, Ronald E.; Anderson, Daniel B.; ...

2017-08-07

Energy-efficient and scalable harvesting and lipid extraction processes must be developed in order for the algal biofuels and bioproducts industry to thrive. The major challenge for harvesting is the handling of large volumes of cultivation water to concentrate low amounts of biomass. For lipid extraction, the major energy and cost drivers are associated with disrupting the algae cell wall and drying the biomass before solvent extraction of the lipids. Here we review the research and development conducted by the Harvesting and Extraction Team during the 3-year National Alliance for Advanced Biofuels and Bioproducts (NAABB) algal consortium project. The harvesting andmore » extraction team investigated five harvesting and three wet extraction technologies at lab bench scale for effectiveness, and conducted a techoeconomic study to evaluate their costs and energy efficiency compared to available baseline technologies. Based on this study, three harvesting technologies were selected for further study at larger scale. We evaluated the selected harvesting technologies: electrocoagulation, membrane filtration, and ultrasonic harvesting, in a field study at minimum scale of 100 L/h. None of the extraction technologies were determined to be ready for scale-up; therefore, an emerging extraction technology (wet solvent extraction) was selected from industry to provide scale-up data and capabilities to produce lipid and lipid-extracted materials for the NAABB program. One specialized extraction/adsorption technology was developed that showed promise for recovering high value co-products from lipid extracts. Overall, the NAABB Harvesting and Extraction Team improved the readiness level of several innovative, energy efficient technologies to integrate with algae production processes and captured valuable lessons learned about scale-up challenges.« less

Review of the harvesting and extraction program within the National Alliance for Advanced Biofuels and Bioproducts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marrone, Babetta L.; Lacey, Ronald E.; Anderson, Daniel B.

Energy-efficient and scalable harvesting and lipid extraction processes must be developed in order for the algal biofuels and bioproducts industry to thrive. The major challenge for harvesting is the handling of large volumes of cultivation water to concentrate low amounts of biomass. For lipid extraction, the major energy and cost drivers are associated with disrupting the algae cell wall and drying the biomass before solvent extraction of the lipids. Here we review the research and development conducted by the Harvesting and Extraction Team during the 3-year National Alliance for Advanced Biofuels and Bioproducts (NAABB) algal consortium project. The harvesting andmore » extraction team investigated five harvesting and three wet extraction technologies at lab bench scale for effectiveness, and conducted a techoeconomic study to evaluate their costs and energy efficiency compared to available baseline technologies. Based on this study, three harvesting technologies were selected for further study at larger scale. We evaluated the selected harvesting technologies: electrocoagulation, membrane filtration, and ultrasonic harvesting, in a field study at minimum scale of 100 L/h. None of the extraction technologies were determined to be ready for scale-up; therefore, an emerging extraction technology (wet solvent extraction) was selected from industry to provide scale-up data and capabilities to produce lipid and lipid-extracted materials for the NAABB program. One specialized extraction/adsorption technology was developed that showed promise for recovering high value co-products from lipid extracts. Overall, the NAABB Harvesting and Extraction Team improved the readiness level of several innovative, energy efficient technologies to integrate with algae production processes and captured valuable lessons learned about scale-up challenges.« less

A novel aptamer-based online magnetic solid phase extraction method for the selective determination of 8-hydroxy-2'-deoxyguanosine in human urine.

PubMed

Gan, Haijiao; Xu, Hui

2018-05-30

In this work, an innovative magnetic aptamer adsorbent (Fe 3 O 4 -aptamer MNPs) was synthesized for the selective extraction of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Amino-functionalized-Fe 3 O 4 was crosslinked with 8-OHdG aptamer by glutaraldehyde and fixed into a steel stainless tube as the sorbent of magnetic solid phase extraction (MSPE). After selective extraction by the aptamer adsorbent, the adsorbed 8-OHdG was desorbed dynamically and online analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS). The synthesized sorbent presented outstanding features, including specific selectivity, high enrichment capacity, stability and biocompatibility. Moreover, this proposed MSPE-HPLC-MS can achieve adsorption and desorption operation integration, greatly simplify the analysis process and reduce human errors. When compared with offline MSPE, a sensitivity enhancement of 800 times was obtained for the online method. Some experimental parameters such as the amount of the sorbent, sample flow rate and sample volume, were optimized systematically. Under the optimal conditions, low limit of detection (0.01 ng mL -1 , S/N = 3), limit of quantity (0.03 ng mL -1 , S/N = 10) and wide linear range with a satisfactory correlation coefficient (R 2  ≥ 0.9992) were obtained. And the recoveries of 8-OHdG in the urine samples varied from 82% to 116%. All these results revealed that the method is simple, rapid, selective, sensitive and automated, and it could be expected to become a potential approach for the selective determination of trace 8-OHdG in complex urinary samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Plant extract: a promising biomatrix for ecofriendly, controlled synthesis of silver nanoparticles.

PubMed

Borase, Hemant P; Salunke, Bipinchandra K; Salunkhe, Rahul B; Patil, Chandrashekhar D; Hallsworth, John E; Kim, Beom S; Patil, Satish V

2014-05-01

Uses of plants extracts are found to be more advantageous over chemical, physical and microbial (bacterial, fungal, algal) methods for silver nanoparticles (AgNPs) synthesis. In phytonanosynthesis, biochemical diversity of plant extract, non-pathogenicity, low cost and flexibility in reaction parameters are accounted for high rate of AgNPs production with different shape, size and applications. At the same time, care has to be taken to select suitable phytofactory for AgNPs synthesis based on certain parameters such as easy availability, large-scale nanosynthesis potential and non-toxic nature of plant extract. This review focuses on synthesis of AgNPs with particular emphasis on biological synthesis using plant extracts. Some points have been given on selection of plant extract for AgNPs synthesis and case studies on AgNPs synthesis using different plant extracts. Reaction parameters contributing to higher yield of nanoparticles are presented here. Synthesis mechanisms and overview of present and future applications of plant-extract-synthesized AgNPs are also discussed here. Limitations associated with use of AgNPs are summarised in the present review.

[Validation of Differential Extraction Kit in forensic sexual assault cases].

PubMed

Wu, Dan; Cao, Yu; Xu, Yan; He, Bai-Fang; Bi, Gang; Zhou, Huai-Gu

2009-12-01

To evaluate the validity of Differential Extraction Kit in isolating spermatozoa and epithelial cell DNA from mixture samples. Selective lysis of spermatid and epithelial cells combined with paramagnetic particle method were applied to extract the DNA from the mock samples under controlled conditions and forensic case samples, and template DNA were analyzed by STR genotype method. This Differential Extraction Kit is efficient to obtain high quality spermatid and epithelial cell DNA from the mixture samples with different proportion of sperm to epithelial cell. The Differential Extraction Kit can be applied in DNA extraction for mixed stain from forensic sexual assault samples.

Determination of phthalate esters in soil using a quick, easy, cheap, effective, rugged, and safe method followed by GC-MS.

PubMed

Liu, Qianjun; Chen, Di; Wu, Jiyuan; Yin, Guangcai; Lin, Qintie; Zhang, Min; Hu, Huawen

2018-04-01

A quick, easy, cheap, effective, rugged, and safe procedure was designed to extract pesticide residues from fruits and vegetables with a high percentage of water. It has not been used extensively for the extraction of phthalate esters from sediments, soils, and sludges. In this work, this procedure was combined with gas chromatography with mass spectrometry to determine 16 selected phthalate esters in soil. The extraction efficiency of the samples was improved by ultrasonic extraction and dissolution of the soil samples in ultra-pure water, which promoted the dispersion of the samples. Furthermore, we have simplified the extraction step and reduced the risk of organic solvent contamination by minimizing the use of organic solvents. Different extraction solvents and clean-up adsorbents were compared to optimize the procedure. Dichloromethane/n-hexane (1:1, v/v) and n-hexane/acetone (1:1, v/v) were selected as the extractants from the six extraction solvents tested. C18/primary secondary amine (1:1, m/m) was selected as the sorbent from the five clean-up adsorbents tested. The recoveries from the spiked soils ranged from 70.00 to 117.90% with relative standard deviation values of 0.67-4.62%. The proposed approach was satisfactorily applied for the determination of phthalate esters in 12 contaminated soil samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solid-phase extraction using bis(indolyl)methane-modified silica reinforced with multiwalled carbon nanotubes for the simultaneous determination of flavonoids and aromatic organic acid preservatives.

PubMed

Wang, Na; Liao, Yuan; Wang, Jiamin; Tang, Sheng; Shao, Shijun

2015-12-01

A novel bis(indolyl)methane-modified silica reinforced with multiwalled carbon nanotubes sorbent for solid-phase extraction was designed and synthesized by chemical immobilization of nitro-substituted 3,3'-bis(indolyl)methane on silica modified with multiwalled carbon nanotubes. Coupled with high-performance liquid chromatography analysis, the extraction properties of the sorbent were evaluated for flavonoids and aromatic organic acid compounds. Under optimum conditions, the sorbent can simultaneously extract five flavonoids and two aromatic organic acid preservatives in aqueous solutions in a single-step solid-phase extraction procedure. Wide linear ranges were obtained with correlation coefficients (R(2) ) ranging from 0.9843 to 0.9976, and the limits of detection were in the range of 0.5-5 μg/L for the compounds tested. Compared with the silica modified with multiwalled carbon nanotubes sorbent and the nitro-substituted 3,3'-bis(indolyl)methane-modified silica sorbent, the developed sorbent exhibited higher extraction efficiency toward the selected analytes. The synergistic effect of nitro-substituted 3,3'-bis(indolyl)methane and multiwalled carbon nanotubes not only improved the surface-to-volume ratio but also enhanced multiple intermolecular interactions, such as hydrogen bonds, π-π, and hydrophobic interactions, between the new sorbent and the selected analytes. The as-established solid-phase extraction with high-performance liquid chromatography and diode array detection method was successfully applied to the simultaneous determination of flavonoids and aromatic organic acid preservatives in grape juices with recoveries ranging from 83.9 to 112% for all the selected analytes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a Solid Phase Extraction Method for Agricultural Pesticides in Large-Volume Water Samples

EPA Science Inventory

An analytical method using solid phase extraction (SPE) and analysis by gas chromatography/mass spectrometry (GC/MS) was developed for the trace determination of a variety of agricultural pesticides and selected transformation products in large-volume high-elevation lake water sa...

[Study on extraction technology of soyasaponins from residual of bean ware].

PubMed

Lu, Rumei; Zhang, Yizhen; Bi, Yi

2003-04-01

To find out the optimum extraction technology of soyasaponins from residual of bean ware. The optimum extraction conditions were investigated by the orthogonal design, and the content of soyasaponins was determined by UV-spectro-pho-tometry. The optimum extraction technology was A3B1C1, that is adding 7 times and 6 times amount of 70% alcohol and refluxing for two times and each time for 1.0 h. The selected technology showed higher yield of soyasaponins, good stability and high efficient.

Frequency of data extraction errors and methods to increase data extraction quality: a methodological review.

PubMed

Mathes, Tim; Klaßen, Pauline; Pieper, Dawid

2017-11-28

Our objective was to assess the frequency of data extraction errors and its potential impact on results in systematic reviews. Furthermore, we evaluated the effect of different extraction methods, reviewer characteristics and reviewer training on error rates and results. We performed a systematic review of methodological literature in PubMed, Cochrane methodological registry, and by manual searches (12/2016). Studies were selected by two reviewers independently. Data were extracted in standardized tables by one reviewer and verified by a second. The analysis included six studies; four studies on extraction error frequency, one study comparing different reviewer extraction methods and two studies comparing different reviewer characteristics. We did not find a study on reviewer training. There was a high rate of extraction errors (up to 50%). Errors often had an influence on effect estimates. Different data extraction methods and reviewer characteristics had moderate effect on extraction error rates and effect estimates. The evidence base for established standards of data extraction seems weak despite the high prevalence of extraction errors. More comparative studies are needed to get deeper insights into the influence of different extraction methods.

Chemoecological Screening Reveals High Bioactivity in Diverse Culturable Portuguese Marine Cyanobacteria

PubMed Central

Leão, Pedro N.; Ramos, Vitor; Gonçalves, Patrício B.; Viana, Flávia; Lage, Olga M.; Gerwick, William H.; Vasconcelos, Vitor M.

2013-01-01

Marine cyanobacteria, notably those from tropical regions, are a rich source of bioactive secondary metabolites. Tropical marine cyanobacteria often grow to high densities in the environment, allowing direct isolation of many secondary metabolites from field-collected material. However, in temperate environments culturing is usually required to produce enough biomass for investigations of their chemical constituents. In this work, we cultured a selection of novel and diverse cyanobacteria isolated from the Portuguese coast, and tested their organic extracts in a series of ecologically-relevant bioassays. The majority of the extracts showed activity in at least one of the bioassays, all of which were run in very small scale. Phylogenetically related isolates exhibited different activity profiles, highlighting the value of microdiversity for bioprospection studies. Furthermore, LC-MS analyses of selected active extracts suggested the presence of previously unidentified secondary metabolites. Overall, the screening strategy employed here, in which previously untapped cyanobacterial diversity was combined with multiple bioassays, proved to be a successful strategy and allowed the selection of several strains for further investigations based on their bioactivity profiles. PMID:23609580

Quantification of trans-1,4-polyisoprene in Eucommia ulmoides by fourier transform infrared spectroscopy and pyrolysis-gas chromatography/mass spectrometry.

PubMed

Takeno, Shinya; Bamba, Takeshi; Nakazawa, Yoshihisa; Fukusaki, Eiichiro; Okazawa, Atsushi; Kobayashi, Akio

2008-04-01

Commercial development of trans-1,4-polyisoprene from Eucommia ulmoides Oliver (EU-rubber) requires specific knowledge on selection of high-rubber-content lines and establishment of agronomic cultivation methods for achieving maximum EU-rubber yield. The development can be facilitated by high-throughput and highly sensitive analytical techniques for EU-rubber extraction and quantification. In this paper, we described an efficient EU-rubber extraction method, and validated that the accuracy was equivalent to that of the conventional Soxhlet extraction method. We also described a highly sensitive quantification method for EU-rubber by Fourier transform infrared spectroscopy (FT-IR) and pyrolysis-gas chromatography/mass spectrometry (PyGC/MS). We successfully applied the extraction/quantification method for study of seasonal changes in EU-rubber content and molecular weight distribution.

Molecularly imprinted polymer cartridges coupled on-line with high performance liquid chromatography for simple and rapid analysis of dextromethorphan in human plasma samples.

PubMed

Moein, Mohammad Mahdi; Javanbakht, Mehran; Akbari-Adergani, Behrouz

2011-04-01

In this paper, a novel method is described for automated determination of dextromethorphan in biological fluids using molecularly imprinted solid-phase extraction (MISPE) as a sample clean-up technique combined with high performance liquid chromatography (HPLC). The water-compatible molecularly imprinted polymers (MIPs) were prepared using methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, chloroform as porogen and dextromethorphan as template molecule. These imprinted polymers were used as solid-phase extraction sorbent for the extraction of dextromethorphan from human plasma samples. Various parameters affecting the extraction efficiency of the MIP cartridges were evaluated. The high selectivity of the sorbent coupled to the high performance liquid chromatographic system permitted a simple and rapid analysis of this drug in plasma samples with limits of detection (LOD) and quantification (LOQ) of 0.12 ng/mL and 0.35 ng/mL, respectively. The MIP selectivity was evaluated by analyzing of the dextromethorphan in presence of several substances with similar molecular structures and properties. Results from the HPLC analyses showed that the recoveries of dextromethorphan using MIP cartridges from human plasma samples in the range of 1-50 ng/mL were higher than 87%. Copyright © 2011 Elsevier B.V. All rights reserved.

Mixed Carboxylic Acid Production by Megasphaera elsdenii from Glucose and Lignocellulosic Hydrolysate

DOE PAGES

Nelson, Robert S.; Peterson, Darren J.; Karp, Eric M.; ...

2017-03-01

Here, volatile fatty acids (VFAs) can be readily produced from many anaerobic microbes and subsequently utilized as precursors to renewable biofuels and biochemicals. Megasphaera elsdenii represents a promising host for production of VFAs, butyric acid (BA) and hexanoic acid (HA). However, due to the toxicity of these acids, product removal via an extractive fermentation system is required to achieve high titers and productivities. Here, we examine multiple aspects of extractive separations to produce BA and HA from glucose and lignocellulosic hydrolysate with M. elsdenii. A mixture of oleyl alcohol and 10% (v/v) trioctylamine was selected as an extraction solvent duemore » to its insignificant inhibitory effect on the bacteria. Batch extractive fermentations were conducted in the pH range of 5.0 to 6.5 to select the best cell growth rate and extraction efficiency combination. Subsequently, fed-batch pertractive fermentations were run over 230 h, demonstrating high BA and HA concentrations in the extracted fraction (57.2 g/L from ~190 g/L glucose) and productivity (0.26 g/L/h). To our knowledge, these are the highest combined acid titers and productivity values reported for M. elsdenii and bacterial mono-cultures from sugars. Lastly, the production of BA and HA (up to 17 g/L) from lignocellulosic sugars was demonstrated.« less

Mixed Carboxylic Acid Production by Megasphaera elsdenii from Glucose and Lignocellulosic Hydrolysate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, Robert S.; Peterson, Darren J.; Karp, Eric M.

Here, volatile fatty acids (VFAs) can be readily produced from many anaerobic microbes and subsequently utilized as precursors to renewable biofuels and biochemicals. Megasphaera elsdenii represents a promising host for production of VFAs, butyric acid (BA) and hexanoic acid (HA). However, due to the toxicity of these acids, product removal via an extractive fermentation system is required to achieve high titers and productivities. Here, we examine multiple aspects of extractive separations to produce BA and HA from glucose and lignocellulosic hydrolysate with M. elsdenii. A mixture of oleyl alcohol and 10% (v/v) trioctylamine was selected as an extraction solvent duemore » to its insignificant inhibitory effect on the bacteria. Batch extractive fermentations were conducted in the pH range of 5.0 to 6.5 to select the best cell growth rate and extraction efficiency combination. Subsequently, fed-batch pertractive fermentations were run over 230 h, demonstrating high BA and HA concentrations in the extracted fraction (57.2 g/L from ~190 g/L glucose) and productivity (0.26 g/L/h). To our knowledge, these are the highest combined acid titers and productivity values reported for M. elsdenii and bacterial mono-cultures from sugars. Lastly, the production of BA and HA (up to 17 g/L) from lignocellulosic sugars was demonstrated.« less

Surfactants assist in lipid extraction from wet Nannochloropsis sp.

PubMed

Wu, Chongchong; Xiao, Ye; Lin, Weiguo; Zhu, Junying; De la Hoz Siegler, Hector; Zong, Mingsheng; Rong, Junfeng

2017-11-01

An efficient approach involving surfactant treatment, or the modification and utilization of surfactants that naturally occur in algae (algal-based surfactants), was developed to assist in the extraction of lipids from wet algae. Surfactants were found to be able to completely replace polar organic solvents in the extraction process. The highest yield of algal lipids extracted by hexane and algal-based surfactants was 78.8%, followed by 78.2% for hexane and oligomeric surfactant extraction, whereas the lipid yield extracted by hexane and ethanol was only 60.5%. In addition, the saponifiable lipids extracted by exploiting algal-based surfactants and hexane, or adding oligomeric surfactant and hexane, accounted for 78.6% and 75.4% of total algal lipids, respectively, which was more than 10% higher than the lipids extracted by hexane and ethanol. This work presents a method to extract lipids from algae using only nonpolar organic solvents, while obtaining high lipid yields and high selectivity to saponifiables. Copyright © 2017 Elsevier Ltd. All rights reserved.

Deltorphins: a family of naturally occurring peptides with high affinity and selectivity for delta opioid binding sites.

PubMed

Erspamer, V; Melchiorri, P; Falconieri-Erspamer, G; Negri, L; Corsi, R; Severini, C; Barra, D; Simmaco, M; Kreil, G

1989-07-01

Deltorphins are endogenous linear heptapeptides, isolated from skin extracts of frogs belonging to the genus Phyllomedusa, that have a higher affinity and selectivity for delta opioid binding sites than any other natural compound known. Two deltorphins with the sequence Tyr-Ala-Phe-Asp(or Glu)-Val-Val-Gly-NH2 have been isolated from skin extracts of Phyllomedusa bicolor. The alanine in position 2 is in the D configuration. These peptides, [D-Ala2]deltorphins I and II, show an even higher affinity for delta receptors than the previously characterized deltorphin, which contains D-methionine as the second amino acid. These peptides show some similarity to another constituent of Phyllomedusa skin, dermorphin, which is highly selective for mu-opioid receptors. These peptides all have the N-terminal sequence Tyr-D-Xaa-Phe, where D-Xaa is either D-alanine or D-methionine. While this structure seems to be capable of activating both mu and delta opioid receptors, differences in the C-terminal regions of these peptides are probably responsible for the observed high receptor selectivity of dermorphin and deltorphin.

Deltorphins: a family of naturally occurring peptides with high affinity and selectivity for delta opioid binding sites.

PubMed Central

Erspamer, V; Melchiorri, P; Falconieri-Erspamer, G; Negri, L; Corsi, R; Severini, C; Barra, D; Simmaco, M; Kreil, G

1989-01-01

Deltorphins are endogenous linear heptapeptides, isolated from skin extracts of frogs belonging to the genus Phyllomedusa, that have a higher affinity and selectivity for delta opioid binding sites than any other natural compound known. Two deltorphins with the sequence Tyr-Ala-Phe-Asp(or Glu)-Val-Val-Gly-NH2 have been isolated from skin extracts of Phyllomedusa bicolor. The alanine in position 2 is in the D configuration. These peptides, [D-Ala2]deltorphins I and II, show an even higher affinity for delta receptors than the previously characterized deltorphin, which contains D-methionine as the second amino acid. These peptides show some similarity to another constituent of Phyllomedusa skin, dermorphin, which is highly selective for mu-opioid receptors. These peptides all have the N-terminal sequence Tyr-D-Xaa-Phe, where D-Xaa is either D-alanine or D-methionine. While this structure seems to be capable of activating both mu and delta opioid receptors, differences in the C-terminal regions of these peptides are probably responsible for the observed high receptor selectivity of dermorphin and deltorphin. PMID:2544892

Selective and comprehensive analysis of organohalogen compounds by GC × GC-HRTofMS and MS/MS.

PubMed

Hashimoto, Shunji; Zushi, Yasuyuki; Takazawa, Yoshikatsu; Ieda, Teruyo; Fushimi, Akihiro; Tanabe, Kiyoshi; Shibata, Yasuyuki

2018-03-01

Thousands of organohalogen compounds, including hazardous chemicals such as polychlorinated biphenyls (PCBs) and other persistent organic pollutants (POPs), were selectively and simultaneously detected and identified with simple, or no, purification from environmental sample extracts by using several advanced methods. The methods used were software extraction from two-dimensional gas chromatography-high-resolution time-of-flight mass spectrometry (GC × GC-HRTofMS) data, measurement by negative chemical ionization with HRTofMS, and neutral loss scanning (NLS) with GC × GC-MS/MS. Global and selective detection of organochlorines and bromines in environmental samples such as sediments and fly ash was achieved by NLS using GC × GC-MS/MS (QQQ), with the expected losses of 35 Cl and 79 Br. We confirmed that negative chemical ionization was effective for sensitive and selective ionization of organohalogens, even using GC × GC-HRTofMS. The 2D total ion chromatograms obtained by using negative chemical ionization and selective extraction of organohalogens using original software from data measured by electron impact ionization were very similar; the software thus functioned well to extract organohalogens. Combining measurements made by using these different methods will help to detect organohalogens selectively and globally. However, to compare the data obtained by individual measurements, the retention times of the peaks on the 2D chromatograms need to match.

Selective capture and rapid identification of Panax notoginseng metabolites in rat faeces by the integration of magnetic molecularly imprinted polymers and high-performance liquid chromatography coupled with orbitrap mass spectrometry.

PubMed

Cai, Qizhi; Yang, Zaiyue; Chen, Ning; Zhou, Xuemin; Hong, Junli

2016-07-15

In the present work, an advanced pretreatment method magnetic molecular imprinted polymers-dispersive solid phase extraction (MMIPs-DSPE) combined with the high sensitivity LTQ-Orbitrap mass spectrometry was applied to the complicated metabolites analysis of Traditional Chinese Medicines (TCMs) in complex matrices. The ginsenoside Rb1 magnetic molecular imprinted polymers (Rb1-MMIPs) were successfully synthesized for specific recognition and selective enrichment of Panax notoginseng saponin metabolites in rat faeces. The polymers were prepared by using Fe3O4@SiO2 as the supporting material, APTES as the functional monomer and TEOS as the cross-linker. The Rb1-MMIPs showed quick separation (10.8 emu/g), large adsorption capacity (636μmol/g), high selectivity and fast binding kinetics (25min). Dispersion solid-phase extraction using Rb1-MMIPs (Rb1-MMIPs-DSPE) integrated with LTQ-Orbitrap MS was applied to fish out and identify saponin metabolites from rat faeces, and totally 58 related compounds were detected within 20min, including 26 PPD-group and 32 PPT-group notoginsenoside metabolites. Parallel tests showed that Rb1-MMIPs-DSPE obtained the lowest matrix effects of 0.98-14.84% and captured the largest number of structural analogues compared with traditional pretreatment methods organic solvent extraction (OSE) and solid phase extraction (SPE). Copyright © 2016 Elsevier B.V. All rights reserved.

Highly selective Ba2+ separations with acyclic, lipophilic di-[N-(X)sulfonyl carbamoyl] polyethers.

PubMed

Elshani, Sadik; Chun, Sangki; Amiri-Eliasi, Bijan; Bartsch, Richard A

2005-01-14

New lipophilic acyclic polyethers with two N-(X)sulfonyl carbamoyl groups of "tunable" acidity exhibit remarkable selectivity for Ba2+ over other alkaline earth metal ions in competitive solvent extraction and transport across polymer inclusion membranes.

Cymbopogon citratus and Camellia sinensis extracts selectively induce apoptosis in cancer cells and reduce growth of lymphoma xenografts in vivo

PubMed Central

Philion, Cory; Ma, Dennis; Ruvinov, Ivan; Mansour, Fadi; Pignanelli, Christopher; Noel, Megan; Saleem, Ammar; Arnason, John; Rodrigues, Mark; Singh, Inderpal; Ropat, Jesse; Pandey, Siyaram

2017-01-01

Cancer cells are reported to have elevated levels of reactive oxygen species (ROS) and are highly dependent on cellular defense mechanisms against oxidative stress. Numerous nutraceuticals and natural polyphenolic compounds have a wide range of abilities to alter cellular redox states with potential implications in various diseases. Furthermore, therapeutic options for cancers are mostly nonselective treatments including genotoxic or tubulin-targeting compounds. Some of the natural extracts, containing multiple bioactive compounds, could target multiple pathways in cancer cells to selectively induce cell death. Cymbopogon citratus (lemongrass) and Camellia sinensis (white tea) extracts have been shown to have medicinal properties, however, their activity against lymphoma and leukemia, as well as mechanistic details, have not been fully characterized. Herein, we report potent anti-cancer properties in dose and time-dependent manners of ethanolic lemongrass and hot water white tea extracts in lymphoma and leukemia models. Both extracts were able to effectively induce apoptosis selectively in these human cancer cell types. Interestingly, ethanolic lemongrass extract induces apoptosis primarily by the extrinsic pathway and was found to be dependent on the generation of ROS. Conversely, apoptotic induction by hot water white tea extract was independent of ROS. Furthermore, both of these extracts caused mitochondrial depolarization and decreased rates of oxygen consumption in lymphoma and leukemia cells, leading to cell death. Most importantly, both these extracts were effective in reducing tumor growth in human lymphoma xenograft models when administered orally. Thus, these natural extracts could have potential for being nontoxic alternatives for the treatment of cancer. PMID:29340014

Toward high-throughput phenotyping: unbiased automated feature extraction and selection from knowledge sources.

PubMed

Yu, Sheng; Liao, Katherine P; Shaw, Stanley Y; Gainer, Vivian S; Churchill, Susanne E; Szolovits, Peter; Murphy, Shawn N; Kohane, Isaac S; Cai, Tianxi

2015-09-01

Analysis of narrative (text) data from electronic health records (EHRs) can improve population-scale phenotyping for clinical and genetic research. Currently, selection of text features for phenotyping algorithms is slow and laborious, requiring extensive and iterative involvement by domain experts. This paper introduces a method to develop phenotyping algorithms in an unbiased manner by automatically extracting and selecting informative features, which can be comparable to expert-curated ones in classification accuracy. Comprehensive medical concepts were collected from publicly available knowledge sources in an automated, unbiased fashion. Natural language processing (NLP) revealed the occurrence patterns of these concepts in EHR narrative notes, which enabled selection of informative features for phenotype classification. When combined with additional codified features, a penalized logistic regression model was trained to classify the target phenotype. The authors applied our method to develop algorithms to identify patients with rheumatoid arthritis and coronary artery disease cases among those with rheumatoid arthritis from a large multi-institutional EHR. The area under the receiver operating characteristic curves (AUC) for classifying RA and CAD using models trained with automated features were 0.951 and 0.929, respectively, compared to the AUCs of 0.938 and 0.929 by models trained with expert-curated features. Models trained with NLP text features selected through an unbiased, automated procedure achieved comparable or slightly higher accuracy than those trained with expert-curated features. The majority of the selected model features were interpretable. The proposed automated feature extraction method, generating highly accurate phenotyping algorithms with improved efficiency, is a significant step toward high-throughput phenotyping. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Synthesis of surface Cr (VI)-imprinted magnetic nanoparticles for selective dispersive solid-phase extraction and determination of Cr (VI) in water samples.

PubMed

Qi, Xue; Gao, Shuang; Ding, Guosheng; Tang, An-Na

2017-01-01

A facile, rapid and selective magnetic dispersed solid-phase extraction (dSPE) method for the extraction and enrichment of Cr (VI) prior to flame atomic absorption spectrometry (AAS) was introduced. For highly selective and efficient extraction, magnetic Cr (VI)-imprinted nanoparticles (Fe 3 O 4 @ Cr (VI) IIPs) were prepared by hyphenating surface ion-imprinted with sol-gel techniques. In the preparation process, chromate (Cr(VI)) was used as the template ion; vinylimidazole and 3-aminopropyltriethoxysilane were selected as organic functional monomer and co-monomer respectively. Another reagent, methacryloxypropyltrimethoxysilane was adopted as coupling agent to form the stable covalent bonding between organic and inorganic phases. The effects of various parameters on the extraction efficiency, such as pH of sample solution, the amount of adsorbent, extraction time, the type and concentration of eluent were systematically investigated. Furthermore, the thermodynamic and kinetic properties of the adsorption process were studied to explore the internal adsorption mechanism. Under optimized conditions, the preconcentration factor, limit of detection and linear range of the established dSPE-AAS method for Cr (VI) were found to be 98, 0.29μgL -1 and 4-140μgL -1 , respectively. The developed method was also successfully applied to the analysis of Cr (VI) in different water samples with satisfactory results, proving its reliability and feasibility in real sample analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of lignin extraction processes: Economic and environmental assessment.

PubMed

Carvajal, Juan C; Gómez, Álvaro; Cardona, Carlos A

2016-08-01

This paper presents the technical-economic and environmental assessment of four lignin extraction processes from two different raw materials (sugarcane bagasse and rice husks). The processes are divided into two categories, the first processes evaluates lignin extraction with prior acid hydrolysis step, while in the second case the extraction processes are evaluated standalone for a total analysis of 16 scenarios. Profitability indicators as the net present value (NPV) and environmental indicators as the potential environmental impact (PEI) are used through a process engineering approach to understand and select the best lignin extraction process. The results show that both economically and environmentally process with sulfites and soda from rice husk presents the best results; however the quality of lignin obtained with sulfites is not suitable for high value-added products. Then, the soda is an interesting option for the extraction of lignin if high quality lignin is required for high value-added products at low costs. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Studies on technology optimization for extracting triterpenoid saponins from Picria felterrae by multi-target grading method].

PubMed

Fang, Hong; Ning, De-sheng; Liang, Xiao-yan

2009-12-01

To study the optimum extraction conditions of triterpenoid saponins from Picria felterrae. The optimum extraction conditions were investigated by the contents of the total glycosides and picfeltarraenine I A and I B, using orthogonal test. The optimum extraction conditions were as follows: using 70% alcohol of 19 times than the amount of original material soaking 3 hours, extracting twice with hot reflux method at 80 degrees C, 3h the first time, 1 h the second time. The selected extraction conditions are convenient and practical with high accuracy, and could be used as a reference for industrial production.

Information Extraction of High Resolution Remote Sensing Images Based on the Calculation of Optimal Segmentation Parameters

PubMed Central

Zhu, Hongchun; Cai, Lijie; Liu, Haiying; Huang, Wei

2016-01-01

Multi-scale image segmentation and the selection of optimal segmentation parameters are the key processes in the object-oriented information extraction of high-resolution remote sensing images. The accuracy of remote sensing special subject information depends on this extraction. On the basis of WorldView-2 high-resolution data, the optimal segmentation parameters methodof object-oriented image segmentation and high-resolution image information extraction, the following processes were conducted in this study. Firstly, the best combination of the bands and weights was determined for the information extraction of high-resolution remote sensing image. An improved weighted mean-variance method was proposed andused to calculatethe optimal segmentation scale. Thereafter, the best shape factor parameter and compact factor parameters were computed with the use of the control variables and the combination of the heterogeneity and homogeneity indexes. Different types of image segmentation parameters were obtained according to the surface features. The high-resolution remote sensing images were multi-scale segmented with the optimal segmentation parameters. Ahierarchical network structure was established by setting the information extraction rules to achieve object-oriented information extraction. This study presents an effective and practical method that can explain expert input judgment by reproducible quantitative measurements. Furthermore the results of this procedure may be incorporated into a classification scheme. PMID:27362762

Information Extraction of High Resolution Remote Sensing Images Based on the Calculation of Optimal Segmentation Parameters.

PubMed

Zhu, Hongchun; Cai, Lijie; Liu, Haiying; Huang, Wei

2016-01-01

Multi-scale image segmentation and the selection of optimal segmentation parameters are the key processes in the object-oriented information extraction of high-resolution remote sensing images. The accuracy of remote sensing special subject information depends on this extraction. On the basis of WorldView-2 high-resolution data, the optimal segmentation parameters methodof object-oriented image segmentation and high-resolution image information extraction, the following processes were conducted in this study. Firstly, the best combination of the bands and weights was determined for the information extraction of high-resolution remote sensing image. An improved weighted mean-variance method was proposed andused to calculatethe optimal segmentation scale. Thereafter, the best shape factor parameter and compact factor parameters were computed with the use of the control variables and the combination of the heterogeneity and homogeneity indexes. Different types of image segmentation parameters were obtained according to the surface features. The high-resolution remote sensing images were multi-scale segmented with the optimal segmentation parameters. Ahierarchical network structure was established by setting the information extraction rules to achieve object-oriented information extraction. This study presents an effective and practical method that can explain expert input judgment by reproducible quantitative measurements. Furthermore the results of this procedure may be incorporated into a classification scheme.

Selective solvent extraction of cellulosic material

DOEpatents

Wang, D.I.C.; Avgerinos, G.C.

1983-07-26

Cellulosic products having a high hemicellulose to lignin weight ratio are obtained by extracting a cellulosic composition with basic ethanol-water solution having a pH between about 12 and about 14 at a temperature between about 15 and about 70 C and for a time period between about 2 and about 80 hours. 6 figs.

Selective solvent extraction of cellulosic material

DOEpatents

Wang, Daniel I. C.; Avgerinos, George C.

1983-01-01

Cellulosic products having a high hemicellulose to lignin weight ratio are obtained by extracting a cellulosic composition with basic ethanol-water solution having a pH between about 12 and about 14 at a temperature between about 15.degree. and about 70.degree. C. and for a time period between about 2 and about 80 hours.

Selective enrichment and determination of monoamine neurotransmitters by CU(II) immobilized magnetic solid phase extraction coupled with high-performance liquid chromatography-fluorescence detection.

PubMed

He, Maofang; Wang, Chaozhan; Wei, Yinmao

2016-01-15

In this paper, iminodiacetic acid-Cu(II) functionalized Fe3O4@SiO2 magnetic nanoparticles were prepared and used as new adsorbents for magnetic solid phase extraction (MSPE) of six monoamine neurotransmitters (MNTs) from rabbit plasma. The selective enrichment of MNTs at pH 5.0 was motivated by the specific coordination interaction between amino groups of MNTs and the immobilized Cu(II). The employed weak acidic extraction condition avoided the oxidation of MNTs, and thus facilitated operation and ensured higher recoveries. Under optimal conditions, the recoveries of six MNTs from rabbit plasma were in the range of 83.9-109.4%, with RSD of 2.0-10.0%. When coupled the Cu(II) immobilized MSPE with high-performance liquid chromatography-fluorescence detection, the method exhibited relatively lower detection limits than the previously reported methods, and the method was successfully used to determine the endogenous MNTs in rabbit plasma. The proposed method has potential application for the determination of MNTs in biological samples. Also, the utilization of coordination interaction to improve the selectivity might open another way to selectively enrich small alkaloids from complex samples. Copyright © 2015 Elsevier B.V. All rights reserved.

New reagent for extraction photomeric determination of anionic surface-active substances

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chernova, R.K.; Yastrebova, N.I.; Pankratov, A.N.

1995-02-01

The new reagent 2,6-diphenyl-4-(4-dimethylamino)styrylpyryl chloride is suggested for extraction photometric determination of anionic surface-active substances (SAS). This reagent possesses high sensitivity and selectivity, and can be used for the determination of both individual SAS of any kind and the total amount of anionic SAS. The reagent was used in analysis of highly mineralized statal waters and for the determination of sulfated products in polyoxyethylated alkylphenols.

The effects of Bombyx mori silk strain and extraction time on the molecular and biological characteristics of sericin.

PubMed

Siritientong, Tippawan; Bonani, Walter; Motta, Antonella; Migliaresi, Claudio; Aramwit, Pornanong

2016-01-01

Sericin was extracted from three strains of Thai Bombyx mori silk cocoons (white shell Chul1/1, greenish shell Chul3/2, and yellow shell Chul4/2) by a high-pressure and high-temperature technique. The characteristics of sericin extracted from different fractions (15, 45, and 60 min extraction process) were compared. No differences in amino acid composition were observed among the three fractions. For all silk strains, sericin extracted from a 15-min process presented the highest molecular weight. The biological potential of the different sericin samples as a bioadditive for 3T3 fibroblast cells was assessed. When comparing sericin extracted from three silk strains, sericin fractions extracted from Chul4/2 improved cell proliferation, while sericin from Chul 1/1 activated Type I collagen production to the highest extent. This study allows the natural variability of sericin obtained from different sources and extraction conditions to be addressed and provides clues for the selection of sericin sources.

A rapid extraction of landslide disaster information research based on GF-1 image

NASA Astrophysics Data System (ADS)

Wang, Sai; Xu, Suning; Peng, Ling; Wang, Zhiyi; Wang, Na

2015-08-01

In recent years, the landslide disasters occurred frequently because of the seismic activity. It brings great harm to people's life. It has caused high attention of the state and the extensive concern of society. In the field of geological disaster, landslide information extraction based on remote sensing has been controversial, but high resolution remote sensing image can improve the accuracy of information extraction effectively with its rich texture and geometry information. Therefore, it is feasible to extract the information of earthquake- triggered landslides with serious surface damage and large scale. Taking the Wenchuan county as the study area, this paper uses multi-scale segmentation method to extract the landslide image object through domestic GF-1 images and DEM data, which uses the estimation of scale parameter tool to determine the optimal segmentation scale; After analyzing the characteristics of landslide high-resolution image comprehensively and selecting spectrum feature, texture feature, geometric features and landform characteristics of the image, we can establish the extracting rules to extract landslide disaster information. The extraction results show that there are 20 landslide whose total area is 521279.31 .Compared with visual interpretation results, the extraction accuracy is 72.22%. This study indicates its efficient and feasible to extract earthquake landslide disaster information based on high resolution remote sensing and it provides important technical support for post-disaster emergency investigation and disaster assessment.

The X-ray properties of high redshift, optically selected QSOs. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Anderson, S. F.

1985-01-01

In order to study the X-ray properties of high redshift QSOs, grism/grens plates covering 17 deg. of sky previously imaged to very sensitive X-ray flux levels with the Einstein Observatory were taken. Following optical selection of the QSO, the archived X-ray image is examined to extract an X-ray flux detection or a sensitive upper limit.

Using Selective Drainage Methods to Extract Continuous Surface Flow from 1-Meter Lidar-Derived Digital Elevation Data

USGS Publications Warehouse

Poppenga, Sandra K.; Worstell, Bruce B.; Stoker, Jason M.; Greenlee, Susan K.

2010-01-01

Digital elevation data commonly are used to extract surface flow features. One source for high-resolution elevation data is light detection and ranging (lidar). Lidar can capture a vast amount of topographic detail because of its fine-scale ability to digitally capture the surface of the earth. Because elevation is a key factor in extracting surface flow features, high-resolution lidar-derived digital elevation models (DEMs) provide the detail needed to consistently integrate hydrography with elevation, land cover, structures, and other geospatial features. The U.S. Geological Survey has developed selective drainage methods to extract continuous surface flow from high-resolution lidar-derived digital elevation data. The lidar-derived continuous surface flow network contains valuable information for water resource management involving flood hazard mapping, flood inundation, and coastal erosion. DEMs used in hydrologic applications typically are processed to remove depressions by filling them. High-resolution DEMs derived from lidar can capture much more detail of the land surface than courser elevation data. Therefore, high-resolution DEMs contain more depressions because of obstructions such as roads, railroads, and other elevated structures. The filling of these depressions can significantly affect the DEM-derived surface flow routing and terrain characteristics in an adverse way. In this report, selective draining methods that modify the elevation surface to drain a depression through an obstruction are presented. If such obstructions are not removed from the elevation data, the filling of depressions to create continuous surface flow can cause the flow to spill over an obstruction in the wrong location. Using this modified elevation surface improves the quality of derived surface flow and retains more of the true surface characteristics by correcting large filled depressions. A reliable flow surface is necessary for deriving a consistently connected drainage network, which is important in understanding surface water movement and developing applications for surface water runoff, flood inundation, and erosion. Improved methods are needed to extract continuous surface flow features from high-resolution elevation data based on lidar.

Metal separations using aqueous biphasic partitioning systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaiko, D.J.; Zaslavsky, B.; Rollins, A.N.

1996-05-01

Aqueous biphasic extraction (ABE) processes offer the potential for low-cost, highly selective separations. This countercurrent extraction technique involves selective partitioning of either dissolved solutes or ultrafine particulates between two immiscible aqueous phases. The extraction systems that the authors have studied are generated by combining an aqueous salt solution with an aqueous polymer solution. They have examined a wide range of applications for ABE, including the treatment of solid and liquid nuclear wastes, decontamination of soils, and processing of mineral ores. They have also conducted fundamental studies of solution microstructure using small angle neutron scattering (SANS). In this report they reviewmore » the physicochemical fundamentals of aqueous biphase formation and discuss the development and scaleup of ABE processes for environmental remediation.« less

Simple guanidinium motif for the selective binding and extraction of sulfate

DOE PAGES

Seipp, Charles A.; Williams, Neil J.; Bryantsev, Vyacheslav S.; ...

2017-06-30

A simple bidentate anion receptor, shown previously to adopt a rigid pseudobicyclic conformation while binding anions in the solid state, selectively binds sulfate in aqueous solutions with logK1 and logK2 values of 3.78 ± 0.12 M-1 and 2.10 ± 0.23 M-1, respectively. This anion receptor has little to no affinity for nitrate and chloride in the same solutions. A lipophilic derivative was synthesized in four steps to yield an extractant that is capable of partitioning sulfate into 1,2 dichloroethane from water in the presence of large excesses of chloride. This extractant demonstrated D values as high as 2.5 with onlymore » 30 mM of anion receptor.« less

Simple guanidinium motif for the selective binding and extraction of sulfate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seipp, Charles A.; Williams, Neil J.; Bryantsev, Vyacheslav S.

A simple bidentate anion receptor, shown previously to adopt a rigid pseudobicyclic conformation while binding anions in the solid state, selectively binds sulfate in aqueous solutions with logK1 and logK2 values of 3.78 ± 0.12 M-1 and 2.10 ± 0.23 M-1, respectively. This anion receptor has little to no affinity for nitrate and chloride in the same solutions. A lipophilic derivative was synthesized in four steps to yield an extractant that is capable of partitioning sulfate into 1,2 dichloroethane from water in the presence of large excesses of chloride. This extractant demonstrated D values as high as 2.5 with onlymore » 30 mM of anion receptor.« less

Potential of Glycosidase from Non-Saccharomyces Isolates for Enhancement of Wine Aroma.

PubMed

Hu, Kai; Qin, Yi; Tao, Yong-Sheng; Zhu, Xiao-Lin; Peng, Chuan-Tao; Ullah, Niamat

2016-04-01

The aim of this work was to rapidly screen indigenous yeasts with high levels of β-glucosidase activity and assess the potential of glycosidase extracts for aroma enhancement in winemaking. A semiquantitative colorimetric assay was applied using 96-well plates to screen yeasts from 3 different regions of China. Isolates with high β-glucosidase activity were confirmed by the commonly used pNP assay. Among 493 non-Saccharomyces isolates belonging to 8 generas, 3 isolates were selected for their high levels of β-glucosidase activity and were identified as Hanseniaspora uvarum, Pichia membranifaciens, and Rhodotorula mucilaginosa by sequence analysis of the 26S rDNA D1/D2 domain. β-Glucosidase in the glycosidase extract from H. uvarum strain showed the highest activity in winemaking conditions among the selected isolates. For aroma enhancement in winemaking, the glycosidase extract from H. uvarum strain exhibited catalytic specificity for aromatic glycosides of C13 -norisoprenoids and some terpenes, enhancing fresh floral, sweet, berry, and nutty aroma characteristics in wine. © 2016 Institute of Food Technologists®

Selective aqueous extraction of organics coupled with trapping by membrane separation

DOEpatents

van Eikeren, Paul; Brose, Daniel J.; Ray, Roderick J.

1991-01-01

An improvement to processes for the selective extractation of organic solutes from organic solvents by water-based extractants is disclosed, the improvement comprising coupling various membrane separation processes with the organic extraction process, the membrane separation process being utilized to continuously recycle the water-based extractant and at the same time selectively remove or concentrate organic solute from the water-based extractant.

Magnetic molecularly imprinted polymer for the selective extraction of quercetagetin from Calendula officinalis extract.

PubMed

Ma, Run-Tian; Shi, Yan-Ping

2015-03-01

A new magnetic molecularly imprinted polymers (MMIPs) for quercetagetin was prepared by surface molecular imprinting method using super paramagnetic core-shell nanoparticle as the supporter. Acrylamide as the functional monomer, ethyleneglycol dimethacrylate as the crosslinker and acetonitrile as the porogen were applied in the preparation process. Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD) and Vibrating sample magnetometer (VSM) were applied to characterize the MMIPs, and High performance liquid chromatography (HPLC) was utilized to analyze the target analytes. The selectivity of quercetagetin MMIPs was evaluated according to their recognition to template and its analogues. Excellent binding for quercetagetin was observed in MMIPs adsorption experiment, and the adsorption isotherm models analysis showed that the homogeneous binding sites were distributed on the surface of the MMIPs. The MMIPs were employed as adsorbents in solid phase extraction for the determination of quercetagetin in Calendula officinalis extracts. Furthermore, this method is fast, simple and could fulfill the determination and extraction of quercetagetin from herbal extract. Copyright © 2014 Elsevier B.V. All rights reserved.

Supercritical Fluid Extraction of Metal Chelate: A Review.

PubMed

Ding, Xin; Liu, Qinli; Hou, Xiongpo; Fang, Tao

2017-03-04

Supercritical fluid extraction (SFE), as a new green extraction technology, has been used in extracting various metal species. The solubilities of chelating agents and corresponding metal chelates are the key factors which influence the efficiency of SFE. Other main properties of them such as stability and selectivity are also reviewed. The extraction mechanisms of mainly used chelating agents are explained by typical examples in this paper. This is the important aspect of SFE of metal ions. Moreover, the extraction efficiencies of metal species also depend on other factors such as temperature, pressure, extraction time and matrix effect. The two main complexation methods namely in-situ and on-line chelating SFE are described in detail. As an efficient chelating agent, tributyl phosphate-nitric acid (TBP-HNO 3 ) complex attracts much attention. The SFE of metal ions, lanthanides and actinides as well as organometallic compounds are also summarized. With the proper selection of ligands, high efficient extraction of metal species can be obtained. As an efficient sample analysis method, supercritical fluid chromatography (SFC) is introduced in this paper. Recently, the extraction method combining ionic liquids (ILs) with supercritical fluid has been becoming a novel technology for treating metal ions. The kinetics related to SFE of metal species is discussed with some specific examples.

Rational approach to solvent system selection for liquid-liquid extraction-assisted sample pretreatment in counter-current chromatography.

PubMed

Wang, Jiajia; Gu, Dongyu; Wang, Miao; Guo, Xinfeng; Li, Haoquan; Dong, Yue; Guo, Hong; Wang, Yi; Fan, Mengqi; Yang, Yi

2017-05-15

A rational liquid-liquid extraction approach was established to pre-treat samples for high-speed counter-current chromatography (HSCCC). n-Hexane-ethyl acetate-methanol-water (4:5:4:5, v/v) and (1:5:1:5, v/v) were selected as solvent systems for liquid-liquid extraction by systematically screening K of target compounds to remove low- and high-polarity impurities in the sample, respectively. After liquid-liquid extraction was performed, 1.4g of crude sample II was obtained from 18.5g of crude sample I which was extracted from the flowers of Robinia pseudoacacia L., and then separated with HSCCC by using a solvent system composed of n-hexane-ethyl acetate-methanol-water (1:2:1:2, v/v). As a result, 31mg of robinin and 37mg of kaempferol 7-O-α-l-rhamnopyranoside were isolated from 200mg of crude sample II in a single run of HSCCC. A scale-up separation was also performed, and 160mg of robinin with 95% purity and 188mg of kaempferol 7-O-α-l-rhamnopyranoside with 97% purity were produced from 1.2g of crude sample II. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation of l-phenylalanine-imprinted solid-phase extraction sorbent by Pickering emulsion polymerization and the selective enrichment of l-phenylalanine from human urine.

PubMed

Li, Ji; Hu, Xiaoling; Guan, Ping; Zhang, Xiaoyan; Qian, Liwei; Zhang, Nan; Du, Chunbao; Song, Renyuan

2016-05-01

A novel l-phenylalanine molecularly imprinted solid-phase extraction sorbent was synthesized by the combination of Pickering emulsion polymerization and ion-pair dummy template imprinting. Compared to other polymerization methods, the molecularly imprinted polymers thus prepared exhibit a high specific surface, large pore diameter, and appropriate particle size. The key parameters for solid-phase extraction were optimized, and the result indicated that the molecularly imprinted polymer thus prepared exhibits a good recovery of 98.9% for l-phenylalanine. Under the optimized conditions of the procedure, an analytical method for l-phenylalanine was well established. By comparing the performance of the molecularly imprinted polymer and a commercial reverse-phase silica gel, the obtained molecularly imprinted polymer as an solid-phase extraction sorbent is more suitable, exhibiting high precision (relative standard deviation 3.2%, n = 4) and a low limit of detection (60.0 ± 1.9 nmol·L(-1) ) for the isolation of l-phenylalanine. Based on these results, the combination of the Pickering emulsion polymerization and ion-pair dummy template imprinting is effective for preparing selective solid-phase extraction sorbents for the separation of amino acids and organic acids from complex biological samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Root yield and quality of sugarbeet hybrids with pollinators selected for sodium, potassium, or amino-nitrogen concentration

USDA-ARS?s Scientific Manuscript database

Sodium, potassium, and amino-nitrogen, collectively referred to as impurities, are natural constituents of sugarbeet that impede sucrose extraction during factory operations. Lines selected specifically for low or high concentration of a single impurity component were crossed as pollinators with a ...

Effective Subcritical Butane Extraction of Bifenthrin Residue in Black Tea.

PubMed

Zhang, Yating; Gu, Lingbiao; Wang, Fei; Kong, Lingjun; Qin, Guangyong

2017-03-30

As a natural and healthy beverage, tea is widely enjoyed; however, the pesticide residues in tea leaves affect the quality and food safety. To develop a highly selective and efficient method for the facile removal of pesticide residues, the subcritical butane extraction (SBE) technique was employed, and three variables involving temperature, time and extraction cycles were studied. The optimum SBE conditions were found to be as follows: extraction temperature 45 °C, extraction time 30 min, number of extraction cycles 1, and in such a condition that the extraction efficiency reached as high as 92%. Further, the catechins, theanine, caffeine and aroma components, which determine the quality of the tea, fluctuated after SBE treatment. Compared with the uncrushed leaves, pesticide residues can more easily be removed from crushed leaves, and the practical extraction efficiency was 97%. These results indicate that SBE is a useful method to efficiently remove the bifenthrin, and as appearance is not relevant in the production process, tea leaves should first be crushed and then extracted in order that residual pesticides are thoroughly removed.

A green deep eutectic solvent dispersive liquid-liquid micro-extraction (DES-DLLME) for the UHPLC-PDA determination of oxyprenylated phenylpropanoids in olive, soy, peanuts, corn, and sunflower oil.

PubMed

Ferrone, Vincenzo; Genovese, Salvatore; Carlucci, Maura; Tiecco, Matteo; Germani, Raimondo; Preziuso, Francesca; Epifano, Francesco; Carlucci, Giuseppe; Taddeo, Vito Alessandro

2018-04-15

A green dispersive liquid-liquid microextraction (DLLME) using deep eutectic solvent (DES) as the extracting solvent has been developed and applied for the simultaneous quantification of ferulic acid, umbelliferone, boropinic acid, 7-isopentenyloxycoumarin, 4'-geranyloxyferulic acid (GOFA), and auraptene in some vegetable oils using ultra high performance liquid chromatography (UHPLC) with photodiode array detection (PDA). All parameters in the extraction step, including selection and loading of both extracting and dispersing solvents, amount of both extractant and disperser solvent were investigated and optimized. PhAA/TMG DES achieved higher recovery and enrichment factor compared to other DESs. The validated method showed good linearity with correlation coefficients, r 2 >0.9990 for all the analytes. Furthermore, this is the first time that eco-friendly solvents are used for the extraction of oxyprenylated phenylpropanoids and the corresponding extract analyzed with ultra high performance liquid chromatography with photodiode array detection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simultaneous determination of four trace estrogens in feces, leachate, tap and groundwater using solid-liquid extraction/auto solid-phase extraction and high-performance liquid chromatography with fluorescence detection.

PubMed

Liu, Na; Shi, Yue-e; Li, Mengyan; Zhang, Ting-di; Gao, Song

2015-10-01

A simple and selective high-performance liquid chromatography method coupled with fluorescence detection was developed for the simultaneous measurement of trace levels of four estrogens (estrone, estradiol, estriol and 17α-ethynyl estradiol) in environmental matrices. For feces samples, solid-liquid extraction was applied with a 1:1 v/v mixture of acetonitrile and ethyl acetate as the extraction solvent. For liquid samples (e.g., leachate and groundwater), hydrophobic/lipophilic balanced automated solid-phase extraction disks were selected due to their high recoveries compared to conventional C18 disks. Chromatographic separations were performed on a reversed-phase C18 column gradient-eluted with a 45:55 v/v mixture of acetonitrile and water. The detection limits were down to 1.1 × 10(-2) (estrone), 4.11 × 10(-4) (estradiol), 5.2 × 10(-3) (estriol) and 7.18 × 10(-3) μg/L (17α-ethynyl estradiol) at excitation/emission wavelengths of 288/310 nm, with recoveries in the range of 96.9 ± 3.2-105.4 ± 3.2% (n = 3). The method was successfully applied to determine estrogens in feces and water samples collected at livestock farms and a major river in Northeast China. We observed relatively high abundance and widespread distribution of all four estrogens in our sample collections, implying the urgency for a comprehensive and intricate investigation of estrogenic fate and contamination in our researched area. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Taming Big Data: An Information Extraction Strategy for Large Clinical Text Corpora.

PubMed

Gundlapalli, Adi V; Divita, Guy; Carter, Marjorie E; Redd, Andrew; Samore, Matthew H; Gupta, Kalpana; Trautner, Barbara

2015-01-01

Concepts of interest for clinical and research purposes are not uniformly distributed in clinical text available in electronic medical records. The purpose of our study was to identify filtering techniques to select 'high yield' documents for increased efficacy and throughput. Using two large corpora of clinical text, we demonstrate the identification of 'high yield' document sets in two unrelated domains: homelessness and indwelling urinary catheters. For homelessness, the high yield set includes homeless program and social work notes. For urinary catheters, concepts were more prevalent in notes from hospitalized patients; nursing notes accounted for a majority of the high yield set. This filtering will enable customization and refining of information extraction pipelines to facilitate extraction of relevant concepts for clinical decision support and other uses.

Optimization of extraction of bioactive compounds from different types of grape pomace produced at wineries and distilleries.

PubMed

Brazinha, Carla; Cadima, Mafalda; Crespo, João G

2014-06-01

Natural extracts obtained from grape pomace are particularly interesting, due to the substantial variety of valuable compounds present with health benefits, specifically phenolic compounds such as anthocyanins, trans-resveratrol, quercetin, and proanthocyanidins. The production of such extracts has been recognized as a profitable way to valorize grape byproducts, which are low-value and most abundant. First, the effect of the solvent on the extraction of bioactive compounds from grape pomace is studied. The selected solvents are water and ethanol, biocompatible and available in wineries and distilleries. Then, different types of grape pomace obtained along the various stages of current industrial winemaking and distillation processes are analyzed. As a result, the best stage of the winemaking and distillation processes for pomace valorization is identified, corresponding to the grape byproduct with the highest potential as source of bioactive compounds. These studies were performed with Vitis vinifera variety of Tempranillo grapes (same year, same vineyard). This work optimizes the production of natural extracts from (byproduct) grape pomace with recognized health benefits, to be used as high value nutraceuticals ingredients. The process proposed uses renewable and low-cost resources existent in wineries and distilleries. The select solvent extracting is a mixture of the biocompatible water and ethanol. The selected fermented grape pomace was chosen from different and comparable types of grape pomace obtained at current winemaking and distillation processes, to be used in extraction without any pretreatment. © 2014 Institute of Food Technologists®

Critical comparison of the on-line and off-line molecularly imprinted solid-phase extraction of patulin coupled with liquid chromatography.

PubMed

Lhotská, Ivona; Holznerová, Anežka; Solich, Petr; Šatínský, Dalibor

2017-12-01

Reaching trace amounts of mycotoxin contamination requires sensitive and selective analytical tools for their determination. Improving the selectivity of sample pretreatment steps covering new and modern extraction techniques is one way to achieve it. Molecularly imprinted polymers as selective sorbent for extraction undoubtedly meet these criteria. The presented work is focused on the hyphenation of on-line molecularly imprinted solid-phase extraction with a chromatography system using a column-switching approach. Making a critical comparison with a simultaneously developed off-line extraction procedure, evaluation of pros and cons of each method, and determining the reliability of both methods on a real sample analysis were carried out. Both high-performance liquid chromatography methods, using off-line extraction on molecularly imprinted polymer and an on-line column-switching approach, were validated, and the validation results were compared against each other. Although automation leads to significant time savings, fewer human errors, and required no handling of toxic solvents, it reached worse detection limits (15 versus 6 μg/L), worse recovery values (68.3-123.5 versus 81.2-109.9%), and worse efficiency throughout the entire clean-up process in comparison with the off-line extraction method. The difficulties encountered, the compromises made during the optimization of on-line coupling and their critical evaluation are presented in detail. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Alternatives for Benzene in the Extraction of Bitumen Fume from Exposure Sample Media.

PubMed

Sutter, Benjamin; Ravera, Christel; Hussard, Caroline; Langlois, Eddy

2016-01-01

Benzene is frequently used to extract collected bitumen fumes from personal sampler substrates. However, this solvent is particularly dangerous because of its carcinogenicity (group 1 of the International Agency for Research on Cancer classification). Therefore, to prevent the exposure of laboratory technicians to benzene during the fume extraction step from samplers, a compromise had to be found to identify a less toxic solvent with the same extraction capacity. To compare the extraction capacities of selected solvents, bitumen fumes were generated in the laboratory from three different batches of road surfacing bitumen collected on dedicated bitumen fume samplers. The samplers were then extracted by benzene and the solvents tested. Of 11 selected solvents less toxic than benzene and used in studies on bitumen and bitumen fume analyses, n-hexane and n-heptane were identified as alternatives to benzene. In particular, the results demonstrated that n-heptane was the best candidate solvent for benzene replacement, due to its extraction efficiency comparable to benzene for the three bitumen fumes tested and its low toxicity, which is highly compatible with benzene replacement. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Chemical-quality reconnaissance of the water and surficial bed material in the Delaware River estuary and adjacent New Jersey tributaries, 1980-81

USGS Publications Warehouse

Hochreiter, Joseph J.

1982-01-01

This report presents chemical-quality data collected from May 1980 to January 1981 at several locations within the Delaware River estuary and selected New Jersey tributaries. Samples of surface water were analyzed Environmental Protection Agency ' priority pollutants, ' including acid extractable, base/neutral extractable and volatile organic compounds, in addition to selected dissolved inorganic constituents. Surficial bed material at selected locations was examined for trace metals, insecticides, polychlorinated biphenyls, and base/neutral extractable organic compounds. Trace levels (1-50 micrograms per liter) of purgeable organic compounds, particularly those associated with the occurrence of hydrocarbons, were found in about 60% of the water samples taken. DDT, DDD, DDE, PCB 's and chlordane are present in most surficial bed material samples. Diazinon was the only organophosphorous insecticide detected in the study (1.6 micrograms per kilogram at one location). High values for select trace metals in bed material were discovered at two locations. Of the 10 sites sampled, the surficial bed material containing the most contamination was found along one cross section of Raccoon Creek at Bridgeport. An additional analysis of Raccoon Creek revealed bed material containing toluene, oil and grease, and trace quantities of 15 base/neutral extractable organic compounds, including polynuclear aromatic hydrocarbons, phthalate esters, and chlorinated benzenes.

Solidification of floating organic droplet in dispersive liquid-liquid microextraction as a green analytical tool.

PubMed

Mansour, Fotouh R; Danielson, Neil D

2017-08-01

Dispersive liquid-liquid microextraction (DLLME) is a special type of microextraction in which a mixture of two solvents (an extracting solvent and a disperser) is injected into the sample. The extraction solvent is then dispersed as fine droplets in the cloudy sample through manual or mechanical agitation. Hence, the sample is centrifuged to break the formed emulsion and the extracting solvent is manually separated. The organic solvents commonly used in DLLME are halogenated hydrocarbons that are highly toxic. These solvents are heavier than water, so they sink to the bottom of the centrifugation tube which makes the separation step difficult. By using solvents of low density, the organic extractant floats on the sample surface. If the selected solvent such as undecanol has a freezing point in the range 10-25°C, the floating droplet can be solidified using a simple ice-bath, and then transferred out of the sample matrix; this step is known as solidification of floating organic droplet (SFOD). Coupling DLLME to SFOD combines the advantages of both approaches together. The DLLME-SFOD process is controlled by the same variables of conventional liquid-liquid extraction. The organic solvents used as extractants in DLLME-SFOD must be immiscible with water, of lower density, low volatility, high partition coefficient and low melting and freezing points. The extraction efficiency of DLLME-SFOD is affected by types and volumes of organic extractant and disperser, salt addition, pH, temperature, stirring rate and extraction time. This review discusses the principle, optimization variables, advantages and disadvantages and some selected applications of DLLME-SFOD in water, food and biomedical analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Graphene-Templated Synthesis of Magnetic Metal Organic Framework Nanocomposites for Selective Enrichment of Biomolecules.

PubMed

Cheng, Gong; Wang, Zhi-Gang; Denagamage, Sachira; Zheng, Si-Yang

2016-04-27

Successful control of homogeneous and complete coating of graphene or graphene-based composites with well-defined metal organic framework (MOF) layers is a great challenge. Herein, novel magnetic graphene MOF composites were constructed via a simple strategy for self-assembly of well-distributed, dense, and highly porous MOFs on both sides of graphene nanosheets. Graphene functionalized with magnetic nanoparticles and carboxylic groups on both sides was explored as the backbone and template to direct the controllable self-assembly of MOFs. The prepared composite materials have a relatively high specific surface area (345.4 m(2) g(-1)), and their average pore size is measured to be 3.2 nm. Their relatively high saturation magnetization (23.8 emu g(-1)) indicates their strong magnetism at room temperature. Moreover, the multifunctional composite was demonstrated to be a highly effective affinity material in selective extraction and separation of low-concentration biomolecules from biological samples, in virtue of the size-selection property of the unique porous structure and the excellent affinity of the composite materials. Besides providing a solution for the construction of well-defined functional graphene-based MOFs, this work could also contribute to selective extraction of biomolecules, in virtue of the universal affinity between immobilized metal ions and biomolecules.

A Literature Review - Problem Definition Studies on Selected Toxic Chemicals. Volume 3. Occupational Health and Safety Aspects of 2,4,6-Trinitrotoluene (TNT)

DTIC Science & Technology

1978-04-01

crude liver extract, yellow bone marrow extract, a high vitamin (C and B complex) and high caloric diet . However, in spite of intensive treatment, the...protein-rich diet . . . . . 40 B. Effect of Other Food Additives . . . . . . . . . . . 40Si. Vitamin C . . . . . . ... . . . . . . . .. .. 40 ii...uncommon. Hassman (86) in 1971, in a review article about TNT reported that both hypo - and hyper-menorrhea occur in women exposed to TNT. f

Use of advanced techniques for the extraction of phenolic compounds from Tunisian olive leaves: phenolic composition and cytotoxicity against human breast cancer cells.

PubMed

Taamalli, Amani; Arráez-Román, David; Barrajón-Catalán, Enrique; Ruiz-Torres, Verónica; Pérez-Sánchez, Almudena; Herrero, Miguel; Ibañez, Elena; Micol, Vicente; Zarrouk, Mokhtar; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2012-06-01

A comparison among different advanced extraction techniques such as microwave-assisted extraction (MAE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE), together with traditional solid-liquid extraction, was performed to test their efficiency towards the extraction of phenolic compounds from leaves of six Tunisian olive varieties. Extractions were carried out at the best selected conditions for each technique; the obtained extracts were chemically characterized using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS(2)). As expected, higher extraction yields were obtained for PLE while phenolic profiles were mainly influenced by the solvent used as optimum in the different extraction methods. A larger number of phenolic compounds, mostly of a polar character, were found in the extracts obtained by using MAE. Best extraction yields do not correlate with highest cytotoxic activity against breast cancer cells, indicating that cytotoxicity is highly dependent on the presence of certain compounds in the extracts, although not exclusively on a single compound. Therefore, a multifactorial behavior is proposed for the anticancer activity of olive leaf compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.

Deterred drug abuse using superabsorbent polymers.

PubMed

Mastropietro, David J; Muppalaneni, Srinath; Omidian, Hossein

2016-11-01

This study aimed to determine whether selected superabsorbent polymers (SAPs) could be used as a suitable alternative to thwart extraction, filtration, and syringeability attempts for abuse. Many abuse-deterrent formulations (ADFs) rely on high molecular weight polymers such as poly(ethylene oxide) to provide crush and extraction resistance. However, these polymers suffer from slow dissolution kinetics, and are susceptible to a variety of abuse conditions. Several commercially available SAPs were evaluated for swelling behavior in extraction solvents, and tableting properties. Post-compaction abuse properties were evaluated by recoverable volume and syringeability after solvent extraction. Drug release and percent drug extraction were conducted using tramadol HCl as a model drug. Certain SAPs had the ability to rapidly imbibe solvent and effectively stop extraction processes in a variety of solvents, including water and water/alcohol mixtures. Tablets containing SAP and drug showed no effect on drug release in vitro. SAPs possess adequate properties for tableting, and maintain their high and fast swelling properties after compaction. The fast and extensive interactions of SAPs with aqueous medium are a major advantage over non-crosslinked high molecular weight viscosifying agents such as poly(ethylene oxide).

Selective solid-phase extraction using a molecularly imprinted polymer for the analysis of patulin in apple-based foods.

PubMed

Lucci, Paolo; Moret, Sabrina; Bettin, Sara; Conte, Lanfranco

2017-01-01

The aim of this work was to evaluate the use of a molecularly imprinted polymer as a selective solid-phase extraction sorbent for the clean-up and pre-concentration of patulin from apple-based food products. Ultra high pressure liquid chromatography coupled to ultraviolet absorbance detection was used for the analysis of patulin. The molecularly imprinted polymer was applied, for the first time, to the determination of patulin in apple juice, puree and jam samples spiked within the maximum levels specified by the European Commission No. 1881/2006. High recoveries (>77%) were obtained. The method was validated and found to be linear in the range 2-100 μg/kg with correlation coefficients greater than 0.965 and repeatability relative standard deviation below 11% in all cases. Compared with dispersive solid-phase extraction (QuEChERS method) and octadecyl sorbent, the molecularly imprinted polymer showed higher recoveries and selectivity for patulin. The application of Affinisep molecularly imprinted polymer as a selective sorbent material for detection of patulin fulfilled the method performance criteria required by the Commission Regulation No. 401/2006, demonstrating the suitability of the technique for the control of patulin at low ppb levels in different apple-based foods such as juice, puree and jam samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solid-phase extraction method for the isolation of plant thionins from European mistletoe, wheat and barley using zirconium silicate embedded in poly(styrene-co-divinylbenzene) hollow-monoliths.

PubMed

Hussain, Shah; Güzel, Yüksel; Schönbichler, Stefan A; Rainer, Matthias; Huck, Christian W; Bonn, Günther K

2013-09-01

Thionins are cysteine-rich, biologically active small (∼5 kDa) and basic proteins occurring ubiquitously in the plant kingdom. This study describes an efficient solid-phase extraction (SPE) method for the selective isolation of these pharmacologically active proteins. Hollow-monolithic extraction tips based on poly(styrene-co-divinylbenzene) with embedded zirconium silicate nano-powder were designed, which showed an excellent selectivity for sulphur-rich proteins owing to strong co-ordination between zirconium and the sulphur atoms from the thiol-group of cysteine. The sorbent provides a combination of strong hydrophobic and electrostatic interactions which may help in targeted separation of certain classes of proteins in a complex mixture based upon the binding strength of different proteins. European mistletoe, wheat and barley samples were used for selective isolation of viscotoxins, purothionins and hordothionins, respectively. The enriched fractions were subjected to analysis by matrix-assisted laser desorption/ionisation-time-of-flight mass spectrometer to prove the selectivity of the SPE method towards thionins. For peptide mass-fingerprint analysis, tryptic digests of SPE eluates were examined. Reversed-phase high-performance liquid chromatography hyphenated to diode-array detection was employed for the purification of individual isoforms. The developed method was found to be highly specific for the isolation and purification of thionins.

Selective recovery of tagatose from mixtures with galactose by direct extraction with supercritical CO2 and different cosolvents.

PubMed

Montañés, Fernando; Fornari, Tiziana; Martín-Alvarez, Pedro J; Corzo, Nieves; Olano, Agustin; Ibañez, Elena

2006-10-18

A selective fractionation method of carbohydrate mixtures of galactose/tagatose, using supercritical CO(2) and isopropanol as cosolvent, has been evaluated. Optimization was carried out using a central composite face design and considering as factors the extraction pressure (from 100 to 300 bar), the extraction temperature (from 60 to 100 degrees C), and the modifier flow rate (from 0.2 to 0.4 mL/min, which corresponded to a total cosolvent percentage ranging from 4 to 18% vol). The responses evaluated were the amount (milligrams) of tagatose and galactose extracted and their recoveries (percent). The statistical analysis of the results provided mathematical models for each response variable. The corresponding parameters were estimated by multiple linear regression, and high determination coefficients (>0.96) were obtained. The optimum conditions of the extraction process to get the maximum recovery of tagatose (37%) were 300 bar, 60 degrees C, and 0.4 mL/min of cosolvent. The predicted value was 24.37 mg of tagatose, whereas the experimental value was 26.34 mg, which is a 7% error from the predicted value. Cosolvent polarity effects on tagatose extraction from mixtures of galactose/tagatose were also studied using different alcohols and their mixtures with water. Although a remarkable increase of the amount of total carbohydrate extracted with polarity was found, selective extraction of tagatose decreased with increase of polarity of assayed cosolvents. To improve the recovery of extracted tagatose, additional experiments outside the experimental domain were carried out (300 bar, 80 degrees C, and 0.6 mL/min of isopropanol); recoveries >75% of tagatose with purity >90% were obtained.

Use of a Recombinant Fluorescent Substrate with Cleavage Sites for All Botulinum Neurotoxins in High-Throughput Screening of Natural Product Extracts for Inhibitors of Serotypes A, B, and E7

DTIC Science & Technology

2007-12-14

contained dried residues from a collection of terrestrial plants , marine inver- tebrates, and various fungi. NCI plate numbers, sources of extracts, and... plants ), while Fig. 3B displays results from row G of the same plate. In these examples, wells B3, B5, B9, G9, and G12 were selected for further...sources of extracts Plate no. Source Extraction solvent 96110120 Terrestrial plants Water 96110125 Terrestrial plants CH3OH-CH2Cl2 12000707 Marine

The efficacy and safety of nine South African medicinal plants in controlling Bacillus anthracis Sterne vaccine strain.

PubMed

Elisha, Ishaku Leo; Dzoyem, Jean-Paul; Botha, Francien S; Eloff, Jacobus Nicolaas

2016-01-08

Anthrax is a zoonotic disease caused by Bacillus anthracis, a Gram-positive spore-forming bacterium. The presence of the bacteria and the toxins in the blood of infected hosts trigger a cascade of pathological events leading to death. Nine medicinal plants with good activities against other bacteria were selected to determine their in vitro antibacterial activity against Bacillus anthracis Sterne strain. The cytotoxicity of the extracts on Vero kidney cells was also determined. The minimum inhibitory concentration (MIC) values of the extracts against Bacillus anthracis Sterne strain ranged from 0.02 to 0.31 mg/ml. Excellent MIC values were observed for the following plant species: Maesa lanceolata (0.02 mg/ml), Bolusanthus speciosus, Hypericum roeperianum, Morus mesozygia (0.04 mg/ml) and Pittosporum viridiflorum (0.08 mg/ml). The total antibacterial activity of the extracts ranged from 92 to 5562 ml/g. Total activity presents the volume to which the extract from 1 g of plant material can be diluted and still inhibit microbial growth. Maesa lanceolata and Hypericum roeperianum had the highest total activity with values of 5562 and 2999 ml/g respectively. The extracts of Calpurnia aurea had the lowest total activity (92 ml/g). The cytotoxicity determined on Vero cells indicated that most of the extracts were relatively non-toxic compared to doxorubicin (LC50 8.3 ± 1.76 μg/ml), except for the extracts of Maesa lanceolata, Elaeodendron croceum and Calpurnia aurea with LC50 values at 2.38 ± 0.25, 5.20 ± 0.24 and 13 ± 2.26 μg/ml respectively. The selectivity index (SI) ranged from 0.02 to 1.66. Hypericum roeperianum had the best selectivity index, (SI = 1.66) and Elaeodendron croceum had lowest value (SI = 0.02). The crude acetone extracts of the selected plant species had promising antibacterial activity against Bacillus anthracis. Maesa lanceolata extracts could be useful as a disinfectant and Hypericum roeperianum could be useful to protect animals based on its high total activity and selectivity index. Further investigation of these plant extracts may lead to the development of new therapeutic agents to protect humans or animals against anthrax.

Selecting relevant 3D image features of margin sharpness and texture for lung nodule retrieval.

PubMed

Ferreira, José Raniery; de Azevedo-Marques, Paulo Mazzoncini; Oliveira, Marcelo Costa

2017-03-01

Lung cancer is the leading cause of cancer-related deaths in the world. Its diagnosis is a challenge task to specialists due to several aspects on the classification of lung nodules. Therefore, it is important to integrate content-based image retrieval methods on the lung nodule classification process, since they are capable of retrieving similar cases from databases that were previously diagnosed. However, this mechanism depends on extracting relevant image features in order to obtain high efficiency. The goal of this paper is to perform the selection of 3D image features of margin sharpness and texture that can be relevant on the retrieval of similar cancerous and benign lung nodules. A total of 48 3D image attributes were extracted from the nodule volume. Border sharpness features were extracted from perpendicular lines drawn over the lesion boundary. Second-order texture features were extracted from a cooccurrence matrix. Relevant features were selected by a correlation-based method and a statistical significance analysis. Retrieval performance was assessed according to the nodule's potential malignancy on the 10 most similar cases and by the parameters of precision and recall. Statistical significant features reduced retrieval performance. Correlation-based method selected 2 margin sharpness attributes and 6 texture attributes and obtained higher precision compared to all 48 extracted features on similar nodule retrieval. Feature space dimensionality reduction of 83 % obtained higher retrieval performance and presented to be a computationaly low cost method of retrieving similar nodules for the diagnosis of lung cancer.

High Efficiency DNA Extraction by Graphite Oxide/Cellulose/Magnetite Composites Under Na+ Free System

NASA Astrophysics Data System (ADS)

Akceoglu, Garbis Atam; Li, Oi Lun; Saito, Nagahiro

2016-04-01

DNA extraction is the key step at various research areas like biotechnology, diagnostic development, paternity determination, and forensic science . Solid support extraction is the most common method for DNA purification. In this method, Na+ ions have often been applied as binding buffers in order to obtain high extraction efficiency and high quality of DNA; however, the presence of Na+ ions might be interfering with the downstream DNA applications. In this study, we proposed graphite oxide (GO)/magnetite composite/cellulose as an innovative material for Na+-free DNA extraction. The total wt.% of GO was fixed at 4.15% in the GO/cellulose/magnetite composite . The concentration of magnetite within the composites were controlled at 0-3.98 wt.%. The extraction yield of DNA increased with increasing weight percentage of magnetite. The highest yield was achieved at 3.98 wt.% magnetite, where the extraction efficiency was reported to be 338.5 ng/µl. The absorbance ratios between 260 nm and 280 nm (A260/A280) of the DNA elution volume was demonstrated as 1.81, indicating the extracted DNA consisted of high purity. The mechanism of adsorption of DNA was provided by (1) π-π interaction between the aromatic ring in GO and nucleobases of DNA molecule, and (2) surface charge interaction between the positive charge magnetite and anions such as phosphates within the DNA molecules. The results proved that the GO/cellulose/magnetite composite provides a Na+-free method for selective DNA extraction with high extraction efficiency of pure DNA.

Synthesis, characterization and evaluation of uniformly sized core-shell imprinted microspheres for the separation trans-resveratrol from giant knotweed

NASA Astrophysics Data System (ADS)

Zhang, Zhaohui; Liu, Li; Li, Hui; Yao, Shouzhuo

2009-09-01

A novel core-shell molecularly imprinting microspheres (MIMs) with trans-resveratrol as the template molecule; acrylamide (AA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker, was prepared based on SiO 2 microspheres with surface imprinting technique. These core-shell trans-resveratrol imprinted microspheres were characterized by infrared spectra (IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and high performance liquid chromatography (HPLC). The results showed that these core-shell imprinted microspheres, which take on perfect spherical shape with average shell thickness of 150 nm, exhibit especially selective recognition for trans-resveratrol. These imprinted microspheres were applied as solid-phase extraction materials for selective extraction of trans-resveratrol from giant knotweed extracting solution successfully.

Process for recovering actinide values

DOEpatents

Horwitz, E. Philip; Mason, George W.

1980-01-01

A process for rendering actinide values recoverable from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorous extractants such as tri-n butyl phosphate (TBP) and dihexyl-N,N-diethyl carbamylmethylene phosphonate (DHDECAMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is preferably made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant is recycled after stripping the degradation products with a neutral sodium carbonate solution.

Essential Oil Variability and Biological Activities of Tetraclinis articulata (Vahl) Mast. Wood According to the Extraction Time.

PubMed

Djouahri, Abderrahmane; Saka, Boualem; Boudarene, Lynda; Baaliouamer, Aoumeur

2016-12-01

In the present work, the hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) kinetics of essential oil (EO) extracted from Tetraclinis articulata (Vahl) Mast. wood was conducted, in order to assess the impact of extraction time and technique on chemical composition and biological activities. Gas chromatography (GC) and GC/mass spectrometry analyses showed significant differences between the extracted EOs, where each family class or component presents a specific kinetic according to extraction time, technique and especially for the major components: camphene, linalool, cedrol, carvacrol and α-acorenol. Furthermore, our findings showed a high variability for both antioxidant and anti-inflammatory activities, where each activity has a specific effect according to extraction time and technique. The highlighted variability reflects the high impact of extraction time and technique on chemical composition and biological activities, which led to conclude that we should select EOs to be investigated carefully depending on extraction time and technique, in order to isolate the bioactive components or to have the best quality of EO in terms of biological activities and preventive effects in food. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

Highly efficient extraction of anthocyanins from grape skin using deep eutectic solvents as green and tunable media.

PubMed

Jeong, Kyung Min; Zhao, Jing; Jin, Yan; Heo, Seong Rok; Han, Se Young; Yoo, Da Eun; Lee, Jeongmi

2015-12-01

Deep eutectic solvents (DESs) were investigated as tunable, environmentally benign, yet superior extraction media to enhance the extraction of anthocyanins from grape skin, which is usually discarded as waste. Ten DESs containing choline chloride as hydrogen bond acceptor combined with different hydrogen bond donors were screened for high extraction efficiencies based on the anthocyanin extraction yields. As a result, citric acid, D-(+)-maltose, and fructose were selected as the effective DES components, and the newly designed DES, CM-6 that is composed of citric acid and D-(+)-maltose at 4:1 molar ratio, exhibited significantly higher levels of anthocyanin extraction yields than conventional extraction solvents such as 80% aqueous methanol. The final extraction method was established based on the ultrasound-assisted extraction under conditions optimized using response surface methodology. Its extraction yields were double or even higher than those of conventional methods that are time-consuming and use volatile organic solvents. Our method is truly a green method for anthocyanin extraction with great extraction efficiency using a minimal amount of time and solvent. Moreover, this study suggested that grape skin, the by-products of grape juice processing, could serve as a valuable source for safe, natural colorants or antioxidants by use of the eco-friendly extraction solvent, CM-6.

Integrated feature extraction and selection for neuroimage classification

NASA Astrophysics Data System (ADS)

Fan, Yong; Shen, Dinggang

2009-02-01

Feature extraction and selection are of great importance in neuroimage classification for identifying informative features and reducing feature dimensionality, which are generally implemented as two separate steps. This paper presents an integrated feature extraction and selection algorithm with two iterative steps: constrained subspace learning based feature extraction and support vector machine (SVM) based feature selection. The subspace learning based feature extraction focuses on the brain regions with higher possibility of being affected by the disease under study, while the possibility of brain regions being affected by disease is estimated by the SVM based feature selection, in conjunction with SVM classification. This algorithm can not only take into account the inter-correlation among different brain regions, but also overcome the limitation of traditional subspace learning based feature extraction methods. To achieve robust performance and optimal selection of parameters involved in feature extraction, selection, and classification, a bootstrapping strategy is used to generate multiple versions of training and testing sets for parameter optimization, according to the classification performance measured by the area under the ROC (receiver operating characteristic) curve. The integrated feature extraction and selection method is applied to a structural MR image based Alzheimer's disease (AD) study with 98 non-demented and 100 demented subjects. Cross-validation results indicate that the proposed algorithm can improve performance of the traditional subspace learning based classification.

An effective biometric discretization approach to extract highly discriminative, informative, and privacy-protective binary representation

NASA Astrophysics Data System (ADS)

Lim, Meng-Hui; Teoh, Andrew Beng Jin

2011-12-01

Biometric discretization derives a binary string for each user based on an ordered set of biometric features. This representative string ought to be discriminative, informative, and privacy protective when it is employed as a cryptographic key in various security applications upon error correction. However, it is commonly believed that satisfying the first and the second criteria simultaneously is not feasible, and a tradeoff between them is always definite. In this article, we propose an effective fixed bit allocation-based discretization approach which involves discriminative feature extraction, discriminative feature selection, unsupervised quantization (quantization that does not utilize class information), and linearly separable subcode (LSSC)-based encoding to fulfill all the ideal properties of a binary representation extracted for cryptographic applications. In addition, we examine a number of discriminative feature-selection measures for discretization and identify the proper way of setting an important feature-selection parameter. Encouraging experimental results vindicate the feasibility of our approach.

Fundamental studies on the feasibility of deep eutectic solvents for the selective partition of glaucarubinone present in the roots of Simarouba glauca.

PubMed

Kholiya, Faisal; Bhatt, Nidhi; Rathod, Meena R; Meena, Ramavatar; Prasad, Kamalesh

2015-07-14

Several deep eutectic solvents prepared by the complexation of choline chloride as the hydrogen bond acceptor and hydrogen bond donors such as urea, thiourea, ethylene glycol, and glycerol were employed to partition glaucarubinone, an antimalarial compound present in roots of the plant, Simarouba glauca. Among all the solvents, the deep eutectic solvent consisting of the mixture of choline chloride and urea the most suitable to partition the antimalarial compound from the extract selectively. Analytical tools such as high-performance liquid chromatography and electrospray ionization mass spectrometry were used for characterizations, and glaucarubinone extracted from the roots of the plant by conventional solvent extraction method was used as a reference for comparison. The hydrogen and noncovalent bonds formed between glaucarubinone and the deep eutectic solvents could be responsible for the selective partition of the drug molecule. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improved extraction of avocado oil by application of sono-physical processes.

PubMed

Martínez-Padilla, Laura Patricia; Franke, Lisa; Xu, Xin-Qing; Juliano, Pablo

2018-01-01

Ultrasound treatment is known to increase the oil extractability in olive and palm oil processes. This work examined the effect of ultrasound conditioning of avocado puree on oil extractability and quality, at low (18+40kHz) and high (2MHz) frequencies, at litre-scale. Other ultrasound parameters evaluated included high frequency effect (0.4, 0.6, and 2MHz; 5min; 90kJ/kg) and sonication time (2.5-10min at 2MHz), without malaxation. Finally, a megasonic post-malaxation intervention was assessed at selected malaxation times (15, 30, and 60min). Both low and high frequency ultrasound treatments of the non-malaxed avocado puree improved extractability by 15-24% additional oil recovery, with the highest extractability achieved after 2MHz treatments, depending on the fruit maturity and oil content. There was no preferential improvement on oil extractability observed across high frequencies, even though extractability increased with sonication time. Ultrasound treatment also showed a positive effect after puree malaxation. Oils obtained from sonicated purees showed peroxide and free fatty acid values below the industrial specification levels and an increase in total phenolic compounds after 2MHz treatment. High frequency ultrasound conditioning of avocado puree can enhance oil separation and potentially decrease the malaxation time in industrial processes without impacting on oil quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Potassium-Promoted Molybdenum Carbide as a Highly Active and Selective Catalyst for CO2 Conversion to CO.

PubMed

Porosoff, Marc D; Baldwin, Jeffrey W; Peng, Xi; Mpourmpakis, Giannis; Willauer, Heather D

2017-06-09

The high concentration of CO 2 bound in seawater represents a significant opportunity to extract and use this CO 2 as a C 1 feedstock for synthetic fuels. Using an existing process, CO 2 and H 2 can be concurrently extracted from seawater and then catalytically reacted to produce synthetic fuel. Hydrogenating CO 2 directly into liquid hydrocarbons is exceptionally difficult, but by first identifying a catalyst for selective CO production through the reverse water-gas shift (RWGS) reaction, CO can then be hydrogenated to fuel through Fischer-Tropsch (FT) synthesis. Results of this study demonstrate that potassium-promoted molybdenum carbide supported on γ-Al 2 O 3 (K-Mo 2 C/γ-Al 2 O 3 ) is a low-cost, stable, and highly selective catalyst for RWGS over a wide range of conversions. These findings are supported by X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isocratic non-aqueous reversed-phase high-performance liquid chromatographic separation of capsanthin and capsorubin in red peppers (Capsicum annuum L.), paprika and oleoresin.

PubMed

Weissenberg, M; Schaeffler, I; Menagem, E; Barzilai, M; Levy, A

1997-01-03

A simple, rapid high-performance liquid chromatography method has been devised in order to separate and quantify the xanthophylls capsorubin and capasanthin present in red pepper (Capsicum annuum L.) fruits and preparations made from them (paprika and oleoresin). A reversed-phase isocratic non-aqueous system allows the separation of xanthophylls within a few minutes, with detection at 450 nm, using methyl red as internal standard to locate the various carotenoids and xanthophylls found in plant extracts. The selection of extraction solvents, mild saponification conditions, and chromatographic features is evaluated and discussed. The method is proposed for rapid screening of large plant populations, plant selection, as well as for paprika products and oleoresin, and also for nutrition and quality control studies.

[The preliminary study on nursing the extraction of mandibular mesioangular impacted third molar using reversal high-speed air turbine].

PubMed

Song, Juan; Bi, Xiaoqin

2012-08-01

To study the nursing methods and its effect in mandibular mesioangular impacted third molar extraction with reversal high-speed air turbine. 60 patients with mandibular mesioangular impacted third molar were selected in this study, who were treated in Department of Senior Dentists, West China School of Stomatology, Sichuan University, between June to December 2010. They were randomly and equally divided into control group and experimental group (n=30). The former was treated with tradition chisel splint method while the latter was treated with reversal high-speed air turbine extraction and provided appropriate nursing interventions. Postoperative reactions and wound healing status were evaluated through consultation. There were significant differences between control group and experimental group in terms of postoperative bleeding wound, swelling, dry socket and so on (P<0.05). Mandibular mesioangular impacted third molar extraction with reversal high-speed air turbine is effective, and the corresponding nursing measure is worthy further promotion.

The impact of restorative treatment on tooth loss prevention.

PubMed

Caldas Junior, Arnaldo de França; Silveira, Renata Cimões Jovino; Marcenes, Wagner

2003-01-01

A cross-sectional study was carried out to analyze tooth loss resulting from caries in relation to the number of times the extracted tooth had been restored, the type of caries diagnosed (primary or secondary), and socioeconomic indicators of patients from the city of Recife, Brazil. Ten public health centres and ten centres associated with health insurance companies were randomly selected. The size of the sample was calculated using a standard error of 2.5%. A confidence interval of 95% and a 50% prevalence of reasons for extractions were used for calculating the sample. The minimum size of the sample for meeting these requirements was 381 patients. Patients were randomly selected from the list of adults registered at each centre. A total of 410 patients were invited to take part in the study. The response rate was 100%, but 6 patients were excluded due to incompleteness of data in the questionnaire applied. An assessment was made to obtain the number of decayed, missing or filled teeth (DMFT index) and the reasons for extraction. The results showed a highly significant (p < 0.001) relationship between the number of times the tooth indicated for extraction had been restored and the reason for extraction being caries. Furthermore, the majority of teeth extracted due to caries had been restored two or more times. A highly statistically significant association was also observed between one indicator of use of dental services (F/DMFT) and extraction due to caries (p < 0.001). The findings questioned the belief that tooth loss can be prevented in the general population by merely providing restorative treatment.

Influence of extraction conditions on antioxidant properties of passion fruit (Passiflora edulis) peel.

PubMed

Wong, Yuh Shan; Sia, Chiaw Mei; Khoo, Hock Eng; Ang, Yee Kwang; Chang, Sui Kiat; Chang, Sui Kiat; Yim, Hip Seng

2014-01-01

As a by-product of tropical fruit juice industry, passion fruit peel is a valuable functional food. It is rich in antioxidants. To determine its potential antioxidant properties of passion fruit peel, this study aimed to evaluate the effect of extraction conditions on total phenolic content and antioxidant activity. The extraction conditions were selected from different percentages of ethanol (0-100%, v/v), extraction times (60-300 min), and extraction temperatures (25-60°C) that based on the optimal percentage of DPPH radical scavenging activity. The selected extraction condition was applied for further determination of total phenolic content (TPC) of the passion fruit peel extract using Folin-Ciocalteu reagent assay, while the antioxidant activities were evaluated using DPPH and ABTS radicals scavenging assays, ferric reducing antioxidant power (FRAP), and β-carotene bleaching (BCB) assay. The best extraction conditions were 40% ethanol, 60 min extraction time, and extraction temperature of 30°C. The chosen extraction conditions have contributed to the high TPC and antioxidant activity of passion fruit peel. The levels of antioxidant activity obtained from the passion fruit peel were also lower compared to BHA and α-tocopherol. Positive correlations were observed between TPC and antioxidant activities as assessed by DPPH, ABTS, FRAP, and BCB assays. As a waste of passion fruit consumption or by-product of fruit juice industry, its peel could be considered as a potential source of natural antioxidant for possible functional food and industrial applications.

An Efficient Method for Genomic DNA Extraction from Different Molluscs Species

PubMed Central

Pereira, Jorge C.; Chaves, Raquel; Bastos, Estela; Leitão, Alexandra; Guedes-Pinto, Henrique

2011-01-01

The selection of a DNA extraction method is a critical step when subsequent analysis depends on the DNA quality and quantity. Unlike mammals, for which several capable DNA extraction methods have been developed, for molluscs the availability of optimized genomic DNA extraction protocols is clearly insufficient. Several aspects such as animal physiology, the type (e.g., adductor muscle or gills) or quantity of tissue, can explain the lack of efficiency (quality and yield) in molluscs genomic DNA extraction procedure. In an attempt to overcome these aspects, this work describes an efficient method for molluscs genomic DNA extraction that was tested in several species from different orders: Veneridae, Ostreidae, Anomiidae, Cardiidae (Bivalvia) and Muricidae (Gastropoda), with different weight sample tissues. The isolated DNA was of high molecular weight with high yield and purity, even with reduced quantities of tissue. Moreover, the genomic DNA isolated, demonstrated to be suitable for several downstream molecular techniques, such as PCR sequencing among others. PMID:22174651

Development of andrographolide molecularly imprinted polymer for solid-phase extraction

NASA Astrophysics Data System (ADS)

Yin, Xiaoying; Liu, Qingshan; Jiang, Yifan; Luo, Yongming

2011-06-01

A method employing molecularly imprinted polymer (MIP) as selective sorbent for solid-phase extraction (SPE) to pretreat samples was developed. The polymers were prepared by precipitation polymerization with andrographolide as template molecule. The structure of MIP was characterized and its static adsorption capacity was measured by the Scatchard equation. In comparison with C 18-SPE and non-imprinted polymer (NIP) SPE column, MIP-SPE column displays high selectivity and good affinity for andrographolide and dehydroandrographolide for extract of herb Andrographis paniculata ( Burm.f.) Nees (APN). MIP-SPE column capacity was 11.9 ± 0.6 μmol/g and 12.1 ± 0.5 μmol/g for andrographolide and dehydroandrographolide, respectively and was 2-3 times higher than that of other two columns. The precision and accuracy of the method developed were satisfactory with recoveries between 96.4% and 103.8% (RSD 3.1-4.3%, n = 5) and 96.0% and 104.2% (RSD 2.9-3.7%, n = 5) for andrographolide and dehydroandrographolide, respectively. Various real samples were employed to confirm the feasibility of method. This developed method demonstrates the potential of molecularly imprinted solid phase extraction for rapid, selective, and effective sample pretreatment.

Bioactivity of compounds from Acmella oleracea against Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and selectivity to two non-target species.

PubMed

Moreno, Shaiene C; Carvalho, Geraldo A; Picanço, Marcelo C; Morais, Elisangela G F; Pereira, Rogério M

2012-03-01

Tropical plants are recognised sources of bioactive compounds that can be used for pest control. The objective of this study was to evaluate the biological activity of compounds present in Acmella oleracea (Asteracea) against Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), which is the main pest of tomato crops in Latin America. The selectivity of these compounds to the predator Solenopsis saevissima (Smith) (Hymenoptera: Formicidae) and to the pollinator Tetragonisca angustula (Latr.) (Hymenoptera: Apidae: Meliponinae) was also of interest. A bioassay screening with hexane and ethanol extracts from 23 plants was performed. The hexane extract of A. oleraceae was the most active of the extracts and was selected for further study. The following three alkamides were isolated from a hexane extract of the aerial parts of A. oleracea: spilanthol, (E)-N-isobutylundeca-2-en-8,10-diynamide and (R, E)-N-(2-methylbutyl)undeca-2-en-8,10-diynamide. All of the isolated compounds showed insecticidal activity, with spilanthol being the most active (LD(50) = 0.13 µg mg(-1) ) against T. absoluta. The alkamides were selective to both beneficial species studied. The crude hexane extract of A. oleraceae showed high insecticidal activity and can be used to control T. absoluta in organic or conventional crops. Quantification of LD(50) values of isolated compounds against T. absoluta showed that alkamides could serve as potent insecticides for T. absoluta control programmes. Spilanthol was the main alkamide active isolated. This alkamide is the most promising as it has the highest insecticidal activity and is selective to non-target organisms. Copyright © 2011 Society of Chemical Industry.

Assessing similarity analysis of chromatographic fingerprints of Cyclopia subternata extracts as potential screening tool for in vitro glucose utilisation.

PubMed

Schulze, Alexandra E; De Beer, Dalene; Mazibuko, Sithandiwe E; Muller, Christo J F; Roux, Candice; Willenburg, Elize L; Nyunaï, Nyemb; Louw, Johan; Manley, Marena; Joubert, Elizabeth

2016-01-01

Similarity analysis of the phenolic fingerprints of a large number of aqueous extracts of Cyclopia subternata, obtained by high-performance liquid chromatography (HPLC), was evaluated as a potential tool to screen extracts for relative bioactivity. The assessment was based on the (dis)similarity of their fingerprints to that of a reference active extract of C. subternata, proven to enhance glucose uptake in vitro and in vivo. In vitro testing of extracts, selected as being most similar (n = 5; r ≥ 0.962) and most dissimilar (n = 5; r ≤ 0.688) to the reference active extract, showed that no clear pattern in terms of relative glucose uptake efficacy in C2C12 myocytes emerged, irrespective of the dose. Some of the most dissimilar extracts had higher glucose-lowering activity than the reference active extract. Principal component analysis revealed the major compounds responsible for the most variation within the chromatographic fingerprints, as mangiferin, isomangiferin, iriflophenone-3-C-β-D-glucoside-4-O-β-D-glucoside, iriflophenone-3-C-β-D-glucoside, scolymoside, and phloretin-3',5'-di-C-β-D-glucoside. Quantitative analysis of the selected extracts showed that the most dissimilar extracts contained the highest mangiferin and isomangiferin levels, whilst the most similar extracts had the highest scolymoside content. These compounds demonstrated similar glucose uptake efficacy in C2C12 myocytes. It can be concluded that (dis)similarity of chromatographic fingerprints of extracts of unknown activity to that of a proven bioactive extract does not necessarily translate to lower or higher bioactivity.

In vitro and in vivo antimalarial and cytotoxic activity of five plants used in congolese traditional medicine.

PubMed

Lusakibanza, M; Mesia, G; Tona, G; Karemere, S; Lukuka, A; Tits, M; Angenot, L; Frédérich, M

2010-06-16

The in vitro antiplasmodial activity and cytotoxicity of methanolic and dichloromethane extracts from five Congolese plants were evaluated. The plants were selected following an ethnobotanical survey conducted in D.R. Congo and focusing on plants used traditionally to treat malaria. The in vivo antimalarial activity of aqueous and methanolic extracts active in vitro was also determined in mice infected by Plasmodium berghei berghei. The growth inhibition of Plasmodium falciparum strains was evaluated using the measurement of lactate dehydrogenase activity. The extracts (aqueous, CH(3)OH, EtOH and CH(2)Cl(2)) were prepared by maceration and tested in vitro against the 3D7 (chloroquine sensitive) and W2 (chloroquine resistant) strains of Plasmodium falciparum and against the human normal fetal lung fibroblasts WI-38 to determine the selectivity index. Some extracts were also used at the dose of 300 mg/kg to evaluate their activity in mice infected since 4 days by Plasmodium berghei. Two plants presented a very high activity (IC(50)<3 microg/ml). These plants were Strychnos icaja roots bark (MeOH and CH(2)Cl(2)) and Physalis angulata leaves (MeOH and CH(2)Cl(2)). One plant (Anisopappus chinensis whole plant, MeOH and CH(2)Cl(2)) presented a high activity (IC50<15 microg/ml). The extracts of Anisopappus chinensis and Physalis angulata showed also a good inhibition of parasitemia in vivo. Flavonoids, phenolic acids and terpenes were identified in these plants by a general phytochemical screening method. Three plants showed a very interesting antiplasmodial activity (Anisopappus chinensis, Physalis angulata and Strychnos icaja) and one of them showed a good selectivity index (>10, Anisopappus chinensis). Anisopappus chinensis and Physalis angulata were also active in vivo. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Effects of pH on protein components of extracted oil bodies from diverse plant seeds and endogenous protease-induced oleosin hydrolysis.

PubMed

Zhao, Luping; Chen, Yeming; Chen, Yajing; Kong, Xiangzhen; Hua, Yufei

2016-06-01

Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than oleosins with smaller sizes in each plant seed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fully 3D-Printed Preconcentrator for Selective Extraction of Trace Elements in Seawater.

PubMed

Su, Cheng-Kuan; Peng, Pei-Jin; Sun, Yuh-Chang

2015-07-07

In this study, we used a stereolithographic 3D printing technique and polyacrylate polymers to manufacture a solid phase extraction preconcentrator for the selective extraction of trace elements and the removal of unwanted salt matrices, enabling accurate and rapid analyses of trace elements in seawater samples when combined with a quadrupole-based inductively coupled plasma mass spectrometer. To maximize the extraction efficiency, we evaluated the effect of filling the extraction channel with ordered cuboids to improve liquid mixing. Upon automation of the system and optimization of the method, the device allowed highly sensitive and interference-free determination of Mn, Ni, Zn, Cu, Cd, and Pb, with detection limits comparable with those of most conventional methods. The system's analytical reliability was further confirmed through analyses of reference materials and spike analyses of real seawater samples. This study suggests that 3D printing can be a powerful tool for building multilayer fluidic manipulation devices, simplifying the construction of complex experimental components, and facilitating the operation of sophisticated analytical procedures for most sample pretreatment applications.

Extraction and Determination of Quercetin from Ginkgo biloba by DESs-Based Polymer Monolithic Cartridge.

PubMed

Wang, Xiaoqin; Li, Guizhen; Ho Row, Kyung

2017-09-01

Deep eutectic solvents (DES) were formed from choline chloride (ChCl). DES-modified polymer monolithic (DES-M), template molecular polymer monolithic and non-DES-M without a molecular template were synthesized in identical process. These polymer materials were characterized by field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The significant selective adsorption properties of the polymers were assessed by an absorption capacity experiment and solid-phase extraction (SPE). The optimized extraction procedure was as follows: ultrasonic time (30 min), optimal solvent (ethanol) and liquid to material ratio (20 mL g-1). Under this condition, the amount of quercetin extracted from Ginkgo biloba was 290.8 mg g-1. The purification of G. biloba was achieved by the SPE process. Based on the results, DESs-based monolithic cartridges can be used for simple and efficient extraction and as a pre-concentration technique for the purification of bioactive compounds or drugs in aqueous environments with high affinity and selectivity. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A simple and selective method for determination of phthalate biomarkers in vegetable samples by high pressure liquid chromatography-electrospray ionization-tandem mass spectrometry.

PubMed

Zhou, Xi; Cui, Kunyan; Zeng, Feng; Li, Shoucong; Zeng, Zunxiang

2016-06-01

In the present study, solid-phase extraction cartridges including silica reversed-phase Isolute C18, polymeric reversed-phase Oasis HLB and mixed-mode anion-exchange Oasis MAX, and liquid-liquid extractions with ethyl acetate, n-hexane, dichloromethane and its mixtures were compared for clean-up of phthalate monoesters from vegetable samples. Best recoveries and minimised matrix effects were achieved using ethyl acetate/n-hexane liquid-liquid extraction for these target compounds. A simple and selective method, based on sample preparation by ultrasonic extraction and liquid-liquid extraction clean-up, for the determination of phthalate monoesters in vegetable samples by liquid chromatography/electrospray ionisation-tandem mass spectrometry was developed. The method detection limits for phthalate monoesters ranged from 0.013 to 0.120 ng g(-1). Good linearity (r(2)>0.991) between MQLs and 1000× MQLs was achieved. The intra- and inter-day relative standard deviation values were less than 11.8%. The method was successfully used to determine phthalate monoester metabolites in the vegetable samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecularly imprinted polymer online solid-phase extraction coupled with high-performance liquid chromatography-UV for the determination of three sulfonamides in pork and chicken.

PubMed

He, Jinxing; Wang, Shuo; Fang, Guozhen; Zhu, Huaping; Zhang, Yan

2008-05-14

A selective imprinted amino-functionalized silica gel sorbent was prepared by combining a surface molecular imprinting technique with a sol-gel process for online solid-phase extraction-HPLC determination of three trace sulfonamides in pork and chicken muscle. The imprinted functionalized silica gel sorbent exhibited selectivity and fast kinetics for the adsorption and desorption of sulfonamides. With a sample loading flow rate of 4 mL min (-1) for 12.5 min, enhancement factors and detection limits for three sulfonamides ( S/ N = 3) were achieved. The precision (RSD) for nine replicate online sorbent extractions of 5 microg L (-1) sulfonamides was less than 4.5%. The sorbent also offered good linearity ( r (2) > 0.99) for online solid-phase extraction of trace levels of sulfonamides. The method was applied to the determination of sulfonamides in pork and chicken muscle samples. The prepared polymer sorbent shows promise for online solid-phase extraction for HPLC determination of trace levels of sulfonamides in pork and chicken samples.

In vitro antibacterial activity of selected medicinal plants from lower Himalayas.

PubMed

Zulqarnain; Rahim, Abdur; Ahmad, Khalid; Ullah, Faizan; Ullah, Hamid; Nishan, Umar

2015-03-01

The present studies cover antibacterial activity of the crude methanolic extracts of 11 medicinal plants viz. Adhatoda vasica, Bauhenia variegate, Bombax ceiba, Carrisa opaca, Caryopteris grata, Debregeasia salicifolia, Lantana camara, Melia azedarach, Phyllanthus emblica, Pinus roxburghii and Olea ferruginea collected from lower Himalayas against two Gram positive (Staphylococcus aureus, Micrococcus luteus) and two Gram negative (Escherichia coli, Pseudomonas aureginosa) bacterial strains. The extracts were applied at four different concentrations (120 mg/mL, 90mg/mL, 60mg/mL and 30mg/mL) in dimethyl sulfoxide (DMSO) by using agar well diffusion method. Antibacterial activities against Staphylococcus aureus and Micrococcus luteus were observed formethanolic extracts of all the above mentioned plants. Greater antibacterial activity against Pseudomonas aeruginosa was only exhibited by Phyllanthus emblica, Pinus roxburghii, Debregeasia salicifolia and Lantana camara. Escherichia coli was highly resistant to all the plant extracts at all concentrations. It is inferred that methanolic crude extracts of the above mentioned plantsexhibitantibacterial activities against pathogenic bacteria, which proved the ethnobotanical importance of the selected plants that indigenous people use for cure against various diseases.

Prebiotic Potential and Chemical Composition of Seven Culinary Spice Extracts

PubMed Central

Lu, Qing‐Yi; Summanen, Paula H.; Lee, Ru‐Po; Huang, Jianjun; Henning, Susanne M.; Heber, David; Finegold, Sydney M.

2017-01-01

Abstract The objective of this study was to investigate prebiotic potential, chemical composition, and antioxidant capacity of spice extracts. Seven culinary spices including black pepper, cayenne pepper, cinnamon, ginger, Mediterranean oregano, rosemary, and turmeric were extracted with boiling water. Major chemical constituents were characterized by RP‐HPLC‐DAD method and antioxidant capacity was determined by measuring colorimetrically the extent to scavenge ABTS radical cations. Effects of spice extracts on the viability of 88 anaerobic and facultative isolates from intestinal microbiota were determined by using Brucella agar plates containing serial dilutions of extracts. A total of 14 phenolic compounds, a piperine, cinnamic acid, and cinnamaldehyde were identified and quantitated. Spice extracts exhibited high antioxidant capacity that correlated with the total amount of major chemicals. All spice extracts, with the exception of turmeric, enhanced the growth of Bifidobacterium spp. and Lactobacillus spp. All spices exhibited inhibitory activity against selected Ruminococcus species. Cinnamon, oregano, and rosemary were active against selected Fusobacterium strains and cinnamon, rosemary, and turmeric were active against selected Clostridium spp. Some spices displayed prebiotic‐like activity by promoting the growth of beneficial bacteria and suppressing the growth of pathogenic bacteria, suggesting their potential role in the regulation of intestinal microbiota and the enhancement of gastrointestinal health. The identification and quantification of spice‐specific phytochemicals provided insight into the potential influence of these chemicals on the gut microbial communities and activities. Future research on the connections between spice‐induced changes in gut microbiota and host metabolism and disease preventive effect in animal models and humans is needed. PMID:28678344

Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.

2012-07-31

Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed tomore » mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified uranium into uranium oxide. The purified uranium product from step 3 can be disposed of as low level waste, or mixed with enriched uranium for use in a reactor for another fuel cycle. After an introduction on the concept and properties of supercritical fluids, we first report the characterization of the different oxides used for this project. Our extraction system and our online monitoring capability using UV-Vis absorbance spectroscopy directly in sc-CO2 is then presented. Next, the uranium extraction efficiencies and kinetics is demonstrated for different oxides and under different physical and chemical conditions: l/sc -CO2 pressure and temperature, TBP/HNO3 complex used, reductant or complexant used for selectivity, and ionic liquids used as supportive media. To complete the extraction and recovery cycle, we then demonstrate uranium back extraction from the TBP loaded sc-CO2 phase into an aqueous phase and the characterization of the uranium complex formed at the end of this process. Another aspect of this project was to limit proliferation risks by either co-extracting uranium and plutonium, or by leaving plutonium behind by selectively extracting uranium. We report that the former is easily achieved, since plutonium is in the tetravalent or hexavalent oxidation state in the oxidizing environment created by the TBP-nitric acid complex, and is therefore co-extracted. The latter is more challenging, as a reductant or complexant to plutonium has to be used to selectively extract uranium. After undertaking experiments on different reducing or complexing systems (e.g., AcetoHydroxamic Acid (AHA), Fe(II), ascorbic acid), oxalic acid was chosen as it can complex tetravalent actinides (Pu, Np, Th) in the aqueous phase while allowing the extraction of hexavalent uranium in the sc-CO2 phase. Finally, we show results using an alternative media to commonly used aqueous phases: ionic liquids. We show the dissolution of uranium in ionic liquids and its extraction using sc-CO2 with and without the presence of AHA. The possible separation of trivalent actinides from uranium is also demonstrated in ionic liquids using neodymium as a surrogate and diglycolamides as the extractant.« less

Quantitative and qualitative optimization of allergen extraction from peanut and selected tree nuts. Part 1. Screening of optimal extraction conditions using a D-optimal experimental design.

PubMed

L'Hocine, Lamia; Pitre, Mélanie

2016-03-01

A D-optimal design was constructed to optimize allergen extraction efficiency simultaneously from roasted, non-roasted, defatted, and non-defatted almond, hazelnut, peanut, and pistachio flours using three non-denaturing aqueous (phosphate, borate, and carbonate) buffers at various conditions of ionic strength, buffer-to-protein ratio, extraction temperature, and extraction duration. Statistical analysis showed that roasting and non-defatting significantly lowered protein recovery for all nuts. Increasing the temperature and the buffer-to-protein ratio during extraction significantly increased protein recovery, whereas increasing the extraction time had no significant impact. The impact of the three buffers on protein recovery varied significantly among the nuts. Depending on the extraction conditions, protein recovery varied from 19% to 95% for peanut, 31% to 73% for almond, 17% to 64% for pistachio, and 27% to 88% for hazelnut. A modulation by the buffer type and ionic strength of protein and immunoglobuline E binding profiles of extracts was evidenced, where high protein recovery levels did not always correlate with high immunoreactivity. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Two-dimensional solid-phase extraction strategy for the selective enrichment of aminoglycosides in milk.

PubMed

Shen, Aijin; Wei, Jie; Yan, Jingyu; Jin, Gaowa; Ding, Junjie; Yang, Bingcheng; Guo, Zhimou; Zhang, Feifang; Liang, Xinmiao

2017-03-01

An orthogonal two-dimensional solid-phase extraction strategy was established for the selective enrichment of three aminoglycosides including spectinomycin, streptomycin, and dihydrostreptomycin in milk. A reversed-phase liquid chromatography material (C 18 ) and a weak cation-exchange material (TGA) were integrated in a single solid-phase extraction cartridge. The feasibility of two-dimensional clean-up procedure that experienced two-step adsorption, two-step rinsing, and two-step elution was systematically investigated. Based on the orthogonality of reversed-phase and weak cation-exchange procedures, the two-dimensional solid-phase extraction strategy could minimize the interference from the hydrophobic matrix existing in traditional reversed-phase solid-phase extraction. In addition, high ionic strength in the extracts could be effectively removed before the second dimension of weak cation-exchange solid-phase extraction. Combined with liquid chromatography and tandem mass spectrometry, the optimized procedure was validated according to the European Union Commission directive 2002/657/EC. A good performance was achieved in terms of linearity, recovery, precision, decision limit, and detection capability in milk. Finally, the optimized two-dimensional clean-up procedure incorporated with liquid chromatography and tandem mass spectrometry was successfully applied to the rapid monitoring of aminoglycoside residues in milk. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Canola Cake as a Potential Substrate for Proteolytic Enzymes Production by a Selected Strain of Aspergillus oryzae: Selection of Process Conditions and Product Characterization

PubMed Central

Freitas, Adriana C.; Castro, Ruann J. S.; Fontenele, Maria A.; Egito, Antonio S.; Farinas, Cristiane S.; Pinto, Gustavo A. S.

2013-01-01

Oil cakes have excellent nutritional value and offer considerable potential for use in biotechnological processes that employ solid-state fermentation (SSF) for the production of high value products. This work evaluates the feasibility of using canola cake as a substrate for protease production by a selected strain of Aspergillus oryzae cultivated under SSF. The influences of the following process parameters were considered: initial substrate moisture content, incubation temperature, inoculum size, and pH of the buffer used for protease extraction and activity analysis. Maximum protease activity was obtained after cultivating Aspergillus oryzae CCBP 001 at 20°C, using an inoculum size of 107 spores/g in canola cake medium moistened with 40 mL of water to 100 g of cake. Cultivation and extraction under selected conditions increased protease activity 5.8-fold, compared to the initial conditions. Zymogram analysis of the enzymatic extract showed that the protease molecular weights varied between 31 and 200 kDa. The concentrated protease extract induced clotting of casein in 5 min. The results demonstrate the potential application of canola cake for protease production under SSF and contribute to the technological advances needed to increase the efficiency of processes designed to add value to agroindustrial wastes. PMID:24455400

Aqueous enzymatic extraction of Moringa oleifera oil.

PubMed

Mat Yusoff, Masni; Gordon, Michael H; Ezeh, Onyinye; Niranjan, Keshavan

2016-11-15

This paper reports on the extraction of Moringa oleifera (MO) oil by using aqueous enzymatic extraction (AEE) method. The effect of different process parameters on the oil recovery was discovered by using statistical optimization, besides the effect of selected parameters on the formation of its oil-in-water cream emulsions. Within the pre-determined ranges, the use of pH 4.5, moisture/kernel ratio of 8:1 (w/w), and 300stroke/min shaking speed at 40°C for 1h incubation time resulted in highest oil recovery of approximately 70% (goil/g solvent-extracted oil). These optimized parameters also result in a very thin emulsion layer, indicating minute amount of emulsion formed. Zero oil recovery with thick emulsion were observed when the used aqueous phase was re-utilized for another AEE process. The findings suggest that the critical selection of AEE parameters is key to high oil recovery with minimum emulsion formation thereby lowering the load on the de-emulsification step. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fast modal extraction in NASTRAN via the FEER computer program. [based on automatic matrix reduction method for lower modes of structures with many degrees of freedom

NASA Technical Reports Server (NTRS)

Newman, M. B.; Pipano, A.

1973-01-01

A new eigensolution routine, FEER (Fast Eigensolution Extraction Routine), used in conjunction with NASTRAN at Israel Aircraft Industries is described. The FEER program is based on an automatic matrix reduction scheme whereby the lower modes of structures with many degrees of freedom can be accurately extracted from a tridiagonal eigenvalue problem whose size is of the same order of magnitude as the number of required modes. The process is effected without arbitrary lumping of masses at selected node points or selection of nodes to be retained in the analysis set. The results of computational efficiency studies are presented, showing major arithmetic operation counts and actual computer run times of FEER as compared to other methods of eigenvalue extraction, including those available in the NASTRAN READ module. It is concluded that the tridiagonal reduction method used in FEER would serve as a valuable addition to NASTRAN for highly increased efficiency in obtaining structural vibration modes.

Application of ionic liquids based microwave-assisted simultaneous extraction of carnosic acid, rosmarinic acid and essential oil from Rosmarinus officinalis.

PubMed

Liu, Tingting; Sui, Xiaoyu; Zhang, Rongrui; Yang, Lei; Zu, Yuangang; Zhang, Lin; Zhang, Ying; Zhang, Zhonghua

2011-11-25

An ionic liquid based microwave-assisted simultaneous extraction and distillation (ILMSED) method has been developed for the effective extraction of carnosic acid (CA), rosmarinic acid (RA) and essential oil (EO) from Rosmarinus officinalis. A series of 1-alkyl-3-methylimidazolium ionic liquids differing in composition of anion and cation were evaluated for extraction yield in this work. The results obtained indicated that the anions and cations of ionic liquids had influences on the extraction of CA and RA, 1.0M 1-octyl-3-methylimidazolium bromide ([C8mim]Br) solution was selected as solvent. In addition, the ILMSED procedures for the three target ingredients were optimized and compared with other conventional extraction techniques. ILMSED gave the best result due to the highest extraction yield within the shortest extraction time for CA and RA. The novel process developed offered advantages in term of yield and selectivity of EO and shorter isolation time (20 min in comparison of 4h of hydrodistillation), and provides a more valuable EO (with high amount of oxygenated compounds). The microstructures and chemical structures of rosemary samples before and after extraction were also investigated. Moreover, the proposed method was validated by the stability, repeatability and recovery experiments. The results indicated that the developed ILMSED method provided a good alternative for the both extraction of non-volatile compounds (CA and RA) and EO from rosemary as well as other herbs. Copyright © 2011 Elsevier B.V. All rights reserved.

Synthesis of Two-Dimensional Materials by Selective Extraction

DOE PAGES

Naguib, Michael; Gogotsi, Yury

2014-12-09

Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds tomore » form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the precursor materials releases 2D structures. In this Account, in addition to graphene and TMO, we focused on MXenes as an example for the use of selective extraction synthesis to produce novel 2D materials. About 10 new carbides and carbonitrides of transition metals have been produced by this method in the past 3 years. They offer an unusual combination of metallic conductivity and hydrophilicity and show very attractive electrochemical properties. We hope that this Account will encourage researchers to extend the use of selective extraction to other layered material systems that in turn will result in expanding the world of nanomaterials in general and 2D materials in particular, generating new materials that cannot be produced by other means.« less

Synthesis of two-dimensional materials by selective extraction.

PubMed

Naguib, Michael; Gogotsi, Yury

2015-01-20

CONSPECTUS: Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds to form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the precursor materials releases 2D structures. In this Account, in addition to graphene and TMO, we focused on MXenes as an example for the use of selective extraction synthesis to produce novel 2D materials. About 10 new carbides and carbonitrides of transition metals have been produced by this method in the past 3 years. They offer an unusual combination of metallic conductivity and hydrophilicity and show very attractive electrochemical properties. We hope that this Account will encourage researchers to extend the use of selective extraction to other layered material systems that in turn will result in expanding the world of nanomaterials in general and 2D materials in particular, generating new materials that cannot be produced by other means.

Synthesis of Two-Dimensional Materials by Selective Extraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Naguib, Michael; Gogotsi, Yury

Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds tomore » form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the precursor materials releases 2D structures. In this Account, in addition to graphene and TMO, we focused on MXenes as an example for the use of selective extraction synthesis to produce novel 2D materials. About 10 new carbides and carbonitrides of transition metals have been produced by this method in the past 3 years. They offer an unusual combination of metallic conductivity and hydrophilicity and show very attractive electrochemical properties. We hope that this Account will encourage researchers to extend the use of selective extraction to other layered material systems that in turn will result in expanding the world of nanomaterials in general and 2D materials in particular, generating new materials that cannot be produced by other means.« less

Preparation of a reversed-phase/anion-exchange mixed-mode spherical sorbent by Pickering emulsion polymerization for highly selective solid-phase extraction of acidic pharmaceuticals from wastewater.

PubMed

Huang, Chaonan; Li, Yun; Yang, Jiajia; Peng, Junyu; Jin, Jing; Dhanjai; Wang, Jincheng; Chen, Jiping

2017-10-27

The present work represents a simple and effective preparation of a novel mixed-mode anion-exchange (MAX) sorbent based on porous poly[2-(diethylamino)ethyl methacrylate-divinylbenzene] (poly(DEAEMA-DVB)) spherical particles synthesized by one-step Pickering emulsion polymerization. The poly(DEAEMA-DVB) particles were quaternized with 1,4-butanediol diglycidyl ether (BDDE) followed by triethylamine (TEA) via epoxy-amine reaction to offer strong anion exchange properties. The synthesized MAX sorbent was characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, nitrogen adsorption-desorption measurements and elemental analysis. The MAX sorbent possessed regular spherical shape and narrow diameter distribution (15-35μm), a high IEC of 0.54meq/g, with carbon and nitrogen contents of 80.3% and 1.62%, respectively. Compared to poly(DEAEMA-DVB), the MAX sorbent exhibited decreased S BET (390.5 vs. 515.3m 2 g -1 ), pore volume (0.74 vs. 0.85cm 3 g -1 ) and pore size (16.8 vs. 17.3nm). Moreover, changes of N content for producing the MAX sorbent reveal a successful two-step quaternization, which can be highly related to such a high IEC. Finally, the MAX sorbent was successfully evaluated for selective isolation and purification of some selected acidic pharmaceuticals (ketoprofen, KEP; naproxen, NAP; and ibuprofen, IBP) from neutral (hydrocortisone, HYC), basic (carbamazepine, CAZ; amitriptyline, AMT) pharmaceuticals and other interferences in water samples using solid phase extraction (SPE). An efficient analytical method based on the MAX-based mixed-mode SPE coupled with HPLC-UV was developed for highly selective extraction and cleanup of acidic KEP, NAP and IBP in spiked wastewater samples. The developed method exhibited good sensitivity (0.009-0.085μgL -1 limit of detection), satisfactory recoveries (82.1%-105.5%) and repeatabilities (relative standard deviation < 7.9%, n=3). Copyright © 2017 Elsevier B.V. All rights reserved.

Optimization of ultrasonic circulating extraction of samara oil from Acer saccharum using combination of Plackett-Burman design and Box-Behnken design.

PubMed

Chen, Fengli; Zhang, Qiang; Fei, Shimin; Gu, Huiyan; Yang, Lei

2017-03-01

In this study, ultrasonic circulating extraction (UCE) technique was firstly and successfully applied for extraction of samara oil from Acer saccharum. The extraction kinetics were fitted and described, and the extraction mechanism was discussed. Through comparison, n-hexane was selected as the extraction solvent, the influence of solvent type on the responses was detailedly interpreted based on the influence of their properties on the occurrence and intensity of cavitation. Seven parameters potentially influencing the extraction yield of samara oil and content of nervonic acid, including ultrasound irradiation time, ultrasound irradiation power, ultrasound temperature, liquid-solid ratio, soaking time, particle size and stirring rate, were screened through Plackett-Burman design to determine the significant variables. Then, three parameters performed statistically significant, including liquid-solid ratio, ultrasound irradiation time and ultrasound irradiation power, were further optimized using Box-Behnken design to predict optimum extraction conditions. Satisfactory yield of samara oil (11.72±0.38%) and content of nervonic acid (5.28±0.18%) were achieved using the optimal conditions. 1% proportion of ethanol in extraction solvent, 120°C of drying temperature and 6.4% moisture were selected and applied for effective extraction. There were no distinct differences in the physicochemical properties of samara oil obtained by UCE and Soxhlet extraction, and the samara oil obtained by UCE exhibited better antioxidant activities. Therefore, UCE method has enormous potential for efficient extraction of edible oil with high quality from plant materials. Copyright © 2016 Elsevier B.V. All rights reserved.

A combination of solvent extraction and freeze thaw for oil recovery from petroleum refinery wastewater treatment pond sludge.

PubMed

Hu, Guangji; Li, Jianbing; Hou, Haobo

2015-01-01

A combination of solvent extraction and freeze thaw was examined for recovering oil from the high-moisture petroleum refinery wastewater treatment pond sludge. Five solvents including cyclohexane (CHX), dichloromethane (DCM), methyl ethyl ketone (MEK), ethyl acetate (EA), and 2-propanol (2-Pro) were examined. It was found that these solvents except 2-Pro showed a promising oil recovery rate of about 40%, but the recycling of DCM solvent after oil extraction was quite low. Three solvents (CHX, MEK and EA) were then selected for examining the effect of freeze/thaw treatment on improving the quality of recovered oil. This treatment increased the total petroleum hydrocarbon (TPH) content in recovered oil from about 40% to 60% for both MEK and EA extractions, but little effect was observed for CHX extraction. Although the solid residue after oil recovery had a significantly decreased TPH content, a high concentration of heavy metals was observed, indicating that this residue may require proper management. In general, the combination of solvent extraction with freeze/thaw is effective for high-moisture oily hazardous waste treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

Limited Area Coverage/High Resolution Picture Transmission (LAC/HRPT) data vegetative index calculation processor user's manual

NASA Technical Reports Server (NTRS)

Obrien, S. O. (Principal Investigator)

1980-01-01

The program, LACVIN, calculates vegetative indexes numbers on limited area coverage/high resolution picture transmission data for selected IJ grid sections. The IJ grid sections were previously extracted from the full resolution data tapes and stored on disk files.

Extractions of High Quality RNA from the Seeds of Jerusalem Artichoke and Other Plant Species with High Levels of Starch and Lipid.

PubMed

Mornkham, Tanupat; Wangsomnuk, Preeya Puangsomlee; Fu, Yong-Bi; Wangsomnuk, Pinich; Jogloy, Sanun; Patanothai, Aran

2013-04-29

Jerusalem artichoke (Helianthus tuberosus L.) is an important tuber crop. However, Jerusalem artichoke seeds contain high levels of starch and lipid, making the extraction of high-quality RNA extremely difficult and the gene expression analysis challenging. This study was aimed to improve existing methods for extracting total RNA from Jerusalem artichoke dry seeds and to assess the applicability of the improved method in other plant species. Five RNA extraction methods were evaluated on Jerusalem artichoke seeds and two were modified. One modified method with the significant improvement was applied to assay seeds of diverse Jerusalem artichoke accessions, sunflower, rice, maize, peanut and marigold. The effectiveness of the improved method to extract total RNA from seeds was assessed using qPCR analysis of four selected genes. The improved method of Ma and Yang (2011) yielded a maximum RNA solubility and removed most interfering substances. The improved protocol generated 29 to 41 µg RNA/30 mg fresh weight. An A260/A280 ratio of 1.79 to 2.22 showed their RNA purity. Extracted RNA was effective for downstream applications such as first-stranded cDNA synthesis, cDNA cloning and qPCR. The improved method was also effective to extract total RNA from seeds of sunflower, rice, maize and peanut that are rich in polyphenols, lipids and polysaccharides.

Cytotoxicity and antiviral activities of Asplenium nidus, Phaleria macrocarpa and Eleusine indica

NASA Astrophysics Data System (ADS)

Tahir, Mariya Mohd; Ibrahim, Nazlina; Yaacob, Wan Ahmad

2014-09-01

Three local medicinal plants namely Asplenium nidus (langsuyar), Eleusine indica (sambau) and Phaleria macrocarpa (mahkota dewa) were screened for the cytotoxicity and antiviral activities. Six plant extracts were prepared including the aqueous and methanol extracts from A. nidus leaf and root, aqueous extract from dried whole plant of E. indica and methanol extract from P. macrocarpa fruits. Cytotoxicity screening in Vero cell line by MTT assay showed that the CC50 values ranged from 15 to 60 mg/mL thus indicating the safety of the extracts even at high concentrations. Antiviral properties of the plant extracts were determined by plaque reduction assay. The EC50 concentrations were between 3.2 to 47 mg/mL. The selectivity indices (SI = CC50/EC50) of each tested extracts ranged from 4.3 to 63.25 indicating the usefulness of the extracts as potential antiviral agents.

Larvicidal activity and GC-MS analysis of flavonoids of Vitex negundo and Andrographis paniculata against two vector mosquitoes Anopheles stephensi and Aedes aegypti.

PubMed

Gautam, Keerti; Kumar, Padma; Poonia, Sawitri

2013-09-01

Development of insect resistance to synthetic pesticides, high operational cost and environmental pollution have created the need for developing alternative approaches to control vector-borne diseases. In the present study, larvicidal activity of flavonoid extracts of different parts of Vitex negundo (Linnaeus) and Andrographis paniculata (Nees) have been studied against the late III or early IV instar larvae of Aedes aegypti and Anopheles stephensi (Liston). Flavonoids were extracted from different parts of the selected plants using standard method. Bioassay test was carried out by WHO method for determination of larvicidal activity against mosquitoes. Different compounds of the most active extract were identified by the gas chromatography-mass spectrometry (GC-MS) analysis. Flavonoid extract of whole aerial part of A. paniculata was found to be inactive against the selected larvae of Ae. aegypti even at the concentration of 600 ppm, whereas it caused 70% mortality in An. stephensi at the concentration of 200 ppm. Flavonoid extract of flower-buds produced highest mortality (100%) at the concentration of 600 ppm for the late III or early IV instar larvae of Ae. aegypti and at the concentration of 200 ppm for the larvae of An. stephensi. GC-MS analysis of the most active flavonoid extract from flower-buds of Vitex showed 81 peaks. Phenol (26.83% area), naphthalene (4.95% area), 2,3-dihydrobenzofuran (6.79% area), Phenol-2,4-Bis (1,1-dimethyl) (4.49% area), flavones 4'-OH,5-OH,7-di-O-glucoside (0.25% area) and 5-hydroxy- 3,6,7,3',4'-pentamethoxy flavones (0.80% area) were present in major amount. Flavonoid extracts from different parts of two selected plants possess larvicidal activity against two selected mosquito species, hence, could be utilized for developing flavonoid-based, eco-friendly insecticide as an alternative to synthetic insecticides.

An optimized high quality male DNA extraction from spermatophores in open thelycum shrimp species.

PubMed

Planella, Laia; Heras, Sandra; Vera, Manuel; García-Marín, José-Luis; Roldán, María Inés

2017-09-01

The crucial step of most of the current genetic studies is the extraction of DNA of sufficient quantity and quality. Several genomic DNA isolation methods have been described to successfully obtain male DNA from shrimp species. However, all current protocols require invasive handling methods with males for DNA isolation. Using Aristeus antennatus as a model we tested a reliable non-invasive differential DNA extraction method to male DNA isolation from spermatophores attached to female thelycum. The present protocol provides high quality and quantity DNA for polymerase chain reaction amplification and male genotyping. This new approach could be useful to experimental shrimp culture to select sires with relevant genetic patterns for selective breeding programs. More importantly, it can be applied to identify the mating pairs and male structure in wild populations of species as A. antennatus, where males are often difficult to capture. Our method could be also valuable for biological studies on other spermatophore-using species, such as myriapods, arachnids and insects. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Electrochemical in situ fabrication of titanium dioxide-nanosheets on a titanium wire as a novel coating for selective solid-phase microextraction.

PubMed

Li, Yi; Zhang, Min; Yang, Yaoxia; Wang, Xuemei; Du, Xinzhen

2014-09-05

A novel TiO2-nanosheets coated fiber for solid-phase microextraction (SPME) was fabricated by anodization of Ti wire substrates in ethylene glycol with concentrated NH4F. The in situ fabricated TiO2-nanosheets were densely embedded into Ti substrates with about 1μm long, 300nm wide and 80nm thick. The as-fabricated TiO2-nanosheets coating was employed to extract polycyclic aromatic hydrocarbons, phthalates and ultraviolet (UV) filters in combination with high performance liquid chromatography-UV detection (HPLC-UV). It was found that the TiO2-nanosheets coating exhibited high extraction capability and good selectivity for some UV filters frequently used in cosmetic sunscreen formulations. The main parameters affecting extraction performance were investigated and optimized. Under the optimized conditions, the calibration graphs were linear in the range of 0.1-400μgL(-1). The limits of detection of the proposed method were between 0.026μgL(-1) and 0.089μgL(-1) (S/N=3). The single fiber repeatability varied from 4.50% to 8.76% and the fiber-to-fiber reproducibility ranged from 7.75% to 9.64% for the extraction of spiked water with 50μgL(-1) UV filters (n=5). The SPME-HPLC-UV method was successfully established for the selective preconcentration and sensitive detection of target UV filters from real environmental water samples. Recovery of UV filters spiked at 10μgL(-1) and 25μgL(-1) ranged from 88.8% to 107% and the relative standard deviations were less than 9.8%. Furthermore the in situ growth of the TiO2-nanosheets coating was performed in a highly reproducible manner and the TiO2-nanosheets coated fiber has high mechanical strength, good stability and long service life. Copyright © 2014 Elsevier B.V. All rights reserved.

Advanced solvent based methods for molecular characterization of soil organic matter by high-resolution mass spectrometry.

PubMed

Tfaily, Malak M; Chu, Rosalie K; Tolić, Nikola; Roscioli, Kristyn M; Anderton, Christopher R; Paša-Tolić, Ljiljana; Robinson, Errol W; Hess, Nancy J

2015-01-01

Soil organic matter (SOM), a complex, heterogeneous mixture of above and belowground plant litter and animal and microbial residues at various degrees of decomposition, is a key reservoir for carbon (C) and nutrient biogeochemical cycling in soil based ecosystems. A limited understanding of the molecular composition of SOM limits the ability to routinely decipher chemical processes within soil and accurately predict how terrestrial carbon fluxes will respond to changing climatic conditions and land use. To elucidate the molecular-level structure of SOM, we selectively extracted a broad range of intact SOM compounds by a combination of different organic solvents from soils with a wide range of C content. Our use of electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and a suite of solvents with varying polarity significantly expands the inventory of the types of organic molecules present in soils. Specifically, we found that hexane is selective for lipid-like compounds with very low O/C ratios (<0.1); water (H2O) was selective for carbohydrates with high O/C ratios; acetonitrile (ACN) preferentially extracts lignin, condensed structures, and tannin polyphenolic compounds with O/C > 0.5; methanol (MeOH) has higher selectivity toward compounds characterized with low O/C < 0.5; and hexane, MeOH, ACN, and H2O solvents increase the number and types of organic molecules extracted from soil for a broader range of chemically diverse soil types. Our study of SOM molecules by ESI FTICR MS revealed new insight into the molecular-level complexity of organics contained in soils. We present the first comparative study of the molecular composition of SOM from different ecosystems using ultra high-resolution mass spectrometry.

Selective Extraction of Flavonoids from Sophora flavescens Ait. by Mechanochemistry.

PubMed

Zhang, Qihong; Yu, Jingbo; Wang, Yingyao; Su, Weike

2016-07-29

Flavonoids from Sophora flavescens were selectively extracted by mechanochemical-promoted extraction technology (MPET) after using response surface methodology to determine the optimal extraction parameters. The highest yield of 35.17 mg/g was achieved by grinding the roots with Na₂CO₃ (15%) at 440 rpm/min for 17.0 min and water was used as the sole solvent with a ratio of solvent to solid material of 25 mL/g. Flavonoids prepared by MPET demonstrated relatively higher antioxidant activities in subsequent DPPH and hydroxyl radical scavenging assays. Main constituents in the extracts, including kurarinol, kushenol I/N and kurarinone, were characterized by HPLC-MS/MS, indicating good selective extraction by MPET. Physicochemical property changes of powder during mechanochemical milling were identified by scanning electron microscopy, X-ray powder diffraction, and UV-Vis diffuse-reflectance spectroscopy. Compared with traditional extraction methods, MPET possesses notable advantages of higher selectivity, lower extraction temperature, shorter extraction time, and organic solvent free properties.

[Rapid detection of caffeine in blood by freeze-out extraction].

PubMed

Bekhterev, V N; Gavrilova, S N; Kozina, E P; Maslakov, I V

2010-01-01

A new method for the detection of caffeine in blood has been proposed based on the combination of extraction and freezing-out to eliminate the influence of sample matrix. Metrological characteristics of the method are presented. Selectivity of detection is achieved by optimal conditions of analysis by high performance liquid chromatography. The method is technically simple and cost-efficient, it ensures rapid performance of the studies.

Strategy for Extracting DNA from Clay Soil and Detecting a Specific Target Sequence via Selective Enrichment and Real-Time (Quantitative) PCR Amplification ▿

PubMed Central

Yankson, Kweku K.; Steck, Todd R.

2009-01-01

We present a simple strategy for isolating and accurately enumerating target DNA from high-clay-content soils: desorption with buffers, an optional magnetic capture hybridization step, and quantitation via real-time PCR. With the developed technique, μg quantities of DNA were extracted from mg samples of pure kaolinite and a field clay soil. PMID:19633108

Trace quantification of selected sulfonamides in aqueous media by implementation of a new dispersive solid-phase extraction method using a nanomagnetic titanium dioxide graphene-based sorbent and HPLC-UV.

PubMed

Izanloo, Maryam; Esrafili, Ali; Behbahani, Mohammad; Ghambarian, Mahnaz; Reza Sobhi, Hamid

2018-02-01

Herein, a new dispersive solid-phase extraction method using a nano magnetic titanium dioxide graphene-based sorbent in conjunction with high-performance liquid chromatography and ultraviolet detection was successfully developed. The method was proved to be simple, sensitive, and highly efficient for the trace quantification of sulfacetamide, sulfathiazole, sulfamethoxazole, and sulfadiazine in relatively large volume of aqueous media. Initially, the nano magnetic titanium dioxide graphene-based sorbent was successfully synthesized and subsequently characterized by scanning electron microscopy and X-ray diffraction. Then, the sorbent was used for the sorption and extraction of the selected sulfonamides mainly through π-π stacking hydrophobic interactions. Under the established conditions, the calibration curves were linear over the concentration range of 1-200 μg/L. The limit of quantification (precision of 20%, and accuracy of 80-120%) for the detection of each sulfonamide by the proposed method was 1.0 μg/L. To test the extraction efficiency, the method was applied to various fortified real water samples. The average relative recoveries obtained from the fortified samples varied between 90 and 108% with the relative standard deviations of 5.3-10.7%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermo-responsive polymer tethered metal-organic framework core-shell magnetic microspheres for magnetic solid-phase extraction of alkylphenols from environmental water samples.

PubMed

Jia, Yuqian; Su, Hao; Wong, Y-L Elaine; Chen, Xiangfeng; Dominic Chan, T-W

2016-07-22

In this work, the thermo-responsive polymer PNIPAM tethered to Fe3O4@SiO2@MOF core-shell magnetic microspheres was first synthesized by a surface-selective post-synthetic strategy and underwent highly efficient magnetic solid-phase extraction (MSPE) of alkylphenols from aqueous samples. Alkylphenols, including 4-tert-octylphenol (OP) and 4-n-nonylphenol (NP), were selected as target compounds. The sample quantification was carried out using LC-MS/MS in multiple reaction monitor (MRM) mode. Under optimal working conditions, the developed method showed good linearity in the range of 5-1000ngL(-1), a low limit of detection (1.5ngL(-1)), and good repeatability (relative standard deviation, <8%, n=5) for NP and OP. Owning to the hydrophilic/hydrophobic switchable properties of the nanocomposite, high recoveries (78.7-104.3%) of alkylphenols were obtained under different extraction conditions. The levels of OP and NP in environmental samples collected from local river, lake and pond waters were analyzed using the developed method. It was believed that the synthesized material with the thermo-responsive coating, large surface areas and magnetic properties should have great potential in the extraction and removal of alkylphenols from environmental samples. Copyright © 2016 Elsevier B.V. All rights reserved.

ION COMPOSITION ELUCIDATION (ICE): A HIGH ...

EPA Pesticide Factsheets

Unidentified Organic Compounds. For target analytes, standards are purchased, extraction and clean-up procedures are optimized, and mass spectra and retention times for the chromatographic separation are obtained for comparison to the target compounds in environmental sample extracts. This is an efficient approach and selective extraction and clean-up can decrease detection limits for the target compounds relative to analyzing a raw extract containing compounds that yield mass interferences. But selection of a class of compounds for study ignores many potentially toxic compounds. All compounds should be considered, because even trace amounts of compounds found to be endocrine disrupting chemicals might influence embryonic development. Before the toxicology of the hundreds of compounds found in sewage treatment effluents and water reservoirs can be studied alone and in mixtures, they must first be identified. A given compound might be one of the 3800 high production volume chemicals used commercially, a human or microorganism metabolite of such a compound, a photochemical degradation, hydrolysis, or thermal decomposition product, a chlorination or ozonolysis byproduct for drinking water samples, or a naturally occurring compound. Numerous researchers targeting assorted classes of analytes could easily overlook or be unable to identify many of these compounds. Most non-targeted compounds will not be in mass spectral libraries and can seldom be tentatively identifi

The removal of heavy metals from contaminated soil by a combination of sulfidisation and flotation.

PubMed

Vanthuyne, Mathias; Maes, André

2002-05-06

The possibility of removing cadmium, copper, lead and zinc from Belgian loamy soil by a combination of sulfidisation pre-treatment and Denver flotation was investigated. The potentially available--sulfide convertible--metal content of the metal polluted soil was estimated by EDTA (0.1 M, pH 4.65) extraction and BCR sequential extraction. EDTA extraction is better at approximating the metal percentage that is expected to be convertible into a metal sulfide phase, in contrast to the sequential extraction procedure of 'Int. J. Environ. Anal. Chem. 51 (1993) pp. 135-151' in which transition metals present as iron oxide co-precipitates are dissolved by hydroxylammoniumchloride in the second extraction step. To compare the surface characteristics of metal sulfides formed by sulfidisation with those of crystalline metal sulfides, two types of synthetic sediments were prepared and extracted with 0.1 M EDTA (pH 4.65) in anoxic conditions. Separate metal sulfides or co-precipitates with iron sulfide were formed by sulfide conditioning. The Denver flotation of both types of synthetic sediments (kerosene as collector at high background electrolyte concentrations) resulted in similar concentrating factors for freshly formed metal sulfides as for fine-grained crystalline metal sulfides. The selective flotation of metal sulfides after sulfide conditioning of a polluted soil, using kerosene or potassium ethyl xanthate as collectors and MIBC as frother, was studied at high background electrolyte concentrations. The sulfidisations were made in ambient air and inside an anoxic glove box. The concentrating factors corrected by the potentially available metal percentage, determined by 0.1 M EDTA extraction, lie between 2 and 3. The selective flotation of these finely dispersed, amorphous, metal sulfides can possibly be improved by optimising the bubble-particle interaction.

Extraction behaviour and mechanism of Pt(iv) and Pd(ii) by liquid-liquid extraction with an ionic liquid [HBBIm]Br.

PubMed

Liu, Wenhui; Wang, Qi; Zheng, Yan; Wang, Shubin; Yan, Yan; Yang, Yanzhao

2017-06-06

In this study, a method of one-step separation and recycling of high purity Pd(ii) and Pt(iv) using an ionic liquid, 1-butyl-3-benzimidazolium bromate ([HBBIm]Br), was investigated. The effects of [HBBIm]Br concentration, initial metal concentration, and loading capacity of [HBBIm]Br were examined in detail. It was observed that [HBBIm]Br was a very effective extractant for selectively extracting Pd(ii) and precipitating Pt(iv). Through selectively extracting Pd(ii) and precipitating Pt(iv), each metal with high purity was separately obtained from mixed Pd(ii) and Pt(iv) multi-metal solution. The method of one-step separation of Pd(ii) and Pt(iv) is simple and convenient. The anion exchange mechanism between [HBBIm]Br and Pt(iv) was proven through Job's method and FTIR and 1 H NMR spectroscopies. The coordination mechanism between [HBBIm]Br and Pd(ii) was demonstrated via single X-ray diffraction and was found to be robust and distinct, as supported by the ab initio quantum-chemical studies. The crystals of the [PdBr 2 ·2BBIm] complex were formed first. Moreover, the influence of the concentrations of hydrochloric acid, sodium chloride, and sodium nitrate on the precipitation of Pt(iv) and extraction of Pd(ii) was studied herein. It was found that only the concentration of H + could inhibit the separation of Pt(iv) because H + could attract the anion PtCl 6 2- ; thus, the exchange (anion exchange mechanism) between the anions PtCl 6 2- and Br - was prevented. However, both the concentration of H + and Cl - can obviously inhibit the extraction of Pd(ii) because H + and Cl - are the reaction products and increasing their concentration can inhibit the progress of the reaction (coordination mechanism).

Sequential Extraction Results in Improved Proteome Profiling of Medicinal Plant Pinellia ternata Tubers, Which Contain Large Amounts of High-Abundance Proteins

PubMed Central

An, SuFang; Gong, FangPing; Wang, Wei

2012-01-01

Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae. PMID:23185632

Sequential extraction results in improved proteome profiling of medicinal plant Pinellia ternata tubers, which contain large amounts of high-abundance proteins.

PubMed

Wu, Xiaolin; Xiong, Erhui; An, Sufang; Gong, Fangping; Wang, Wei

2012-01-01

Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae.

Molecularly imprinted solid-phase extraction for the selective determination of bromhexine in human serum and urine with high performance liquid chromatography.

PubMed

Javanbakht, Mehran; Namjumanesh, Mohammad Hadi; Akbari-Adergani, Behrouz

2009-11-15

In this work, a novel method is described for the determination of bromhexine in biological fluids using molecularly imprinted solid-phase extraction as the sample cleanup technique combined with high performance liquid chromatography (HPLC). The water-compatible molecularly imprinted polymers (MIPs) were prepared using methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, chloroform as porogen and bromhexine as the template molecule. The novel imprinted polymer was used as a solid-phase extraction sorbent for the extraction of bromhexine from human serum and urine. Various parameters affecting the extraction efficiency of the polymer have been evaluated. The optimal conditions for molecularly imprinted solid-phase extraction (MISPE) consisted of conditioning 1 mL methanol and 1 mL of deionized water at neutral pH, loading of 5 mL of the water sample (25 microg L(-1)) at pH 6.0, washing using 2 mL acetonitrile/acetone (1/4, v/v) and elution with 3x 1 mL methanol/acetic acid (10/1, v/v). The MIP selectivity was evaluated by checking several substances with similar molecular structures to that of bromhexine. Results from the HPLC analyses showed that the calibration curve of bromhexine using MIP from human serum and urine is linear in the ranges of 0.5-100 and 1.5-100 microg L(-1) with good precisions (3.3% and 2.8% for 5.0 microg L(-1)), respectively. The recoveries for serum and urine samples were higher than 92%.

Antileishmanial Potential of Tropical Rainforest Plant Extracts

PubMed Central

Monzote, Lianet; Piñón, Abel; Setzer, William N.

2014-01-01

A total of 115 different plant extracts from our collection, representing 96 plant species, have been evaluated for in vitro antileishmanial activity against L. amazonensis promastigotes. In addition, the extracts were screened for cytotoxic activity against BALB/c mouse macrophages in order to assess a selectivity index. Crude extracts that showed a selectivity index (CC50 for macrophage / IC50 for promastigotes) ≥ 5 or with IC50 < 12.5 μg/mL against promastigotes, a total of 28 extracts, were further screened for anti-amastigote activity. A total of 25 extracts showed promising activity against L. amazonensis promastigotes with low cytotoxic activity. Ten of these extracts showed selectivity indices, (CC50 for macrophages / IC50 for amastigotes) greater than 10 and are considered “hits”, worthy candidates for further phytochemical exploration: Conostegia xalapensis methanol bark extract, Endiandra palmerstonii bark extract, Eugenia monteverdensis acetone bark extract, Eugenia sp. “fine leaf” acetone bark extract, Exothea paniculata chloroform bark extract, Mallotus paniculatus ethanol bark extract, Matelea pseudobarbata ethanol extract, Quercus insignis ethanol bark extract, Sassafras albidum dichloromethane bark extract, and Stemmadenia donnell-smithii acetone bark extract. PMID:28933376

Superfund record of decision (EPA Region 10): McCormick and Baxter Creosoting Company, Portland Plant, Portland, OR, March 29, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-08-01

The decision document presents the selected final remedial actions for the McCormick and Baxter Creosoting Company, Portland Plant site (McCormick and Baxter or site) located in Portland, Oregon. The selected remedy is a series of remedial actions that address the principal threats at the site by treating the most highly contaminated soil, extracting nonaqueous phase liquid (NAPL) and treating contaminated groundwater, and capping the most highly contaminated sediment.

Prebiotic Potential and Chemical Composition of Seven Culinary Spice Extracts.

PubMed

Lu, Qing-Yi; Summanen, Paula H; Lee, Ru-Po; Huang, Jianjun; Henning, Susanne M; Heber, David; Finegold, Sydney M; Li, Zhaoping

2017-08-01

The objective of this study was to investigate prebiotic potential, chemical composition, and antioxidant capacity of spice extracts. Seven culinary spices including black pepper, cayenne pepper, cinnamon, ginger, Mediterranean oregano, rosemary, and turmeric were extracted with boiling water. Major chemical constituents were characterized by RP-HPLC-DAD method and antioxidant capacity was determined by measuring colorimetrically the extent to scavenge ABTS radical cations. Effects of spice extracts on the viability of 88 anaerobic and facultative isolates from intestinal microbiota were determined by using Brucella agar plates containing serial dilutions of extracts. A total of 14 phenolic compounds, a piperine, cinnamic acid, and cinnamaldehyde were identified and quantitated. Spice extracts exhibited high antioxidant capacity that correlated with the total amount of major chemicals. All spice extracts, with the exception of turmeric, enhanced the growth of Bifidobacterium spp. and Lactobacillus spp. All spices exhibited inhibitory activity against selected Ruminococcus species. Cinnamon, oregano, and rosemary were active against selected Fusobacterium strains and cinnamon, rosemary, and turmeric were active against selected Clostridium spp. Some spices displayed prebiotic-like activity by promoting the growth of beneficial bacteria and suppressing the growth of pathogenic bacteria, suggesting their potential role in the regulation of intestinal microbiota and the enhancement of gastrointestinal health. The identification and quantification of spice-specific phytochemicals provided insight into the potential influence of these chemicals on the gut microbial communities and activities. Future research on the connections between spice-induced changes in gut microbiota and host metabolism and disease preventive effect in animal models and humans is needed. © 2017 The Authors. Journal of Food Science published by Wiley Periodicals, Inc. on behalf of Institute of Food Technologists.

A green separation strategy for neodymium (III) from cobalt (II) and nickel (II) using an ionic liquid-based aqueous two-phase system.

PubMed

Chen, Yuehua; Wang, Huiyong; Pei, Yuanchao; Wang, Jianji

2018-05-15

It is significant to develop sustainable strategies for the selective separation of rare earth from transition metals from fundamental and practical viewpoint. In this work, an environmentally friendly solvent extraction approach has been developed to selectively separate neodymium (III) from cobalt (II) and nickel (II) by using an ionic liquid-based aqueous two phase system (IL-ATPS). For this purpose, a hydrophilic ionic liquid (IL) tetrabutylphosphonate nitrate ([P 4444 ][NO 3 ]) was prepared and used for the formation of an ATPS with NaNO 3 . Binodal curves of the ATPSs have been determined for the design of extraction process. The extraction parameters such as contact time, aqueous phase pH, content of phase-formation components of NaNO 3 and the ionic liquid have been investigated systematically. It is shown that under optimal conditions, the extraction efficiency of neodymium (III) is as high as 99.7%, and neodymium (III) can be selectively separated from cobalt (II) and nickel (II) with a separation factor of 10 3 . After extraction, neodymium (III) can be stripped from the IL-rich phase by using dilute aqueous sodium oxalate, and the ILs can be quantitatively recovered and reused in the next extraction process. Since [P 4444 ][NO 3 ] works as one of the components of the ATPS and the extractant for the neodymium, no organic diluent, extra etractant and fluorinated ILs are used in the separation process. Thus, the strategy described here shows potential in green separation of neodymium from cobalt and nickel by using simple IL-based aqueous two-phase system. Copyright © 2018 Elsevier B.V. All rights reserved.

Antioxidant activities of two sweet pepper Capsicum annuum L. varieties phenolic extracts and the effects of thermal treatment

PubMed Central

Yazdizadeh Shotorbani, Narmin; Jamei, Rashid; Heidari, Reza

2013-01-01

Objectives: Sweet peppers Capsicum annuum L. (C. annuum) are an excellent source of vitamins A and C as well as phenolic compounds, which are important antioxidant components that may reduce the risk of diseases. The objective of this study was to evaluate their antioxidant activity under various temperatures. Materials and Methods: To compare the antioxidant activity in various temperatures (20, 35, 50, and 65 °C), two different types of colored (red and green) sweet bell peppers C annuum were selected. The red peppers were selected from those cultivated in Shahreza, Esfahan and the green peppers with the local name of Gijlar were selected from those cultivated in Urmia, West Azarbayjan. The experiments were carried out to measure the total phenolic and flavonoid content, ferric reducing antioxidant power (FRAP), chain-breaking activity, scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), and hydrogen peroxide radicals. Results: Total phenol and flavonoid contents of pepper extracts were enhanced with increasing temperature to 65 °C. Scavenging capacity of DPPH radical of red pepper extract was enhanced because of putting at 50 °C for 30 min and for Gijlar pepper extract scavenging capacity was increased at 65 °C. Scavenging capacity of hydrogen peroxide radical of extracts was the highest at 35 °C. Chain-breaking activity of red pepper extract was increased for 60 min at 35 °C. FRAP (C) of red pepper extract was significantly different (p<0.05) in compare with Gijlar pepper. Conclusion: An appropriate temperature maintained a high antioxidant activity of phenolic compound, which could be due to the combined effect of non enzymatic reaction and phenolic compound stability. PMID:25050256

Production of High Density Aviation Fuels via Novel Zeolite Catalyst Routes

DTIC Science & Technology

1989-10-23

range fraction of a naphthenic crude; saturation of an aromatic FCC cycle stock I the appropriate boiling range: saturation of an appropriate boiling...aromatic hydrocarbons and selected aromatic feedstocks to the corresponding mono- and dicyclic naphthenes in the aviation turbine fuel boiling range; and...Paraffins from Naphthenic Refinery Feed Streams .......... 8 Solvent Extraction ........................................... 8 Shape Selective Catalytic

Evaluation of analgesic, antipyretic and anti-inflammatory activity on Cordia dichotoma G. Forst. Leaf.

PubMed

Gupta, Richa; Kaur, Jagjit

2015-01-01

Cordia dichotoma G. Forst. is an important medicinal plant of family Boraginaceae. Traditionally, its leaves are used to treat fever, headache, and joint pain but its medicinal activities have not been proven by research. To evaluate the analgesic, anti-inflammatory, and antipyretic activity of C. dichotoma G. Forst. leaf extract. The various extracts of leaf powder were prepared by using soxhlet apparatus. The methanol extract was selected for pharmacological study. To evaluate analgesic activity, Eddy's hot plate method, to study anti-inflammatory activity, carageenan-induced rat paw edema method, and to study antipyretic activity, yeast-induced pyrexia method was used. SD female rats (180-200 g) were used for the study. In all three tests, the methanol extract high dose (400 mg/kg) was found to be highly significant as compared to standard drug. This study proved the traditional uses of plant leaves and concluded the analgesic, anti-inflammatory, and antipyretic activity of the leaf methanol extract.

Evaluation of analgesic, antipyretic and anti-inflammatory activity on Cordia dichotoma G. Forst. Leaf

PubMed Central

Gupta, Richa; Kaur, Jagjit

2015-01-01

Background: Cordia dichotoma G. Forst. is an important medicinal plant of family Boraginaceae. Traditionally, its leaves are used to treat fever, headache, and joint pain but its medicinal activities have not been proven by research. Objective: To evaluate the analgesic, anti-inflammatory, and antipyretic activity of C. dichotoma G. Forst. leaf extract. Material and Methods: The various extracts of leaf powder were prepared by using soxhlet apparatus. The methanol extract was selected for pharmacological study. To evaluate analgesic activity, Eddy's hot plate method, to study anti-inflammatory activity, carageenan-induced rat paw edema method, and to study antipyretic activity, yeast-induced pyrexia method was used. SD female rats (180-200 g) were used for the study. Results: In all three tests, the methanol extract high dose (400 mg/kg) was found to be highly significant as compared to standard drug. Conclusion: This study proved the traditional uses of plant leaves and concluded the analgesic, anti-inflammatory, and antipyretic activity of the leaf methanol extract. PMID:25598647

Selective treatment to reduce contamination of propolis by polycyclic aromatic hydrocarbons (PAHs) still preserving its active polyphenol component and antioxidant activity.

PubMed

Galeotti, Fabio; Crimaldi, Laura; Maccari, Francesca; Zaccaria, Vincenzo; Fachini, Alfredo; Volpi, Nicola

2017-09-01

The adverse effects on health and environment caused by polycyclic aromatic hydrocarbons (PAHs) are critical problems. EFSA has defined 16 priority PAHs that are both genotoxic and carcinogenic, and identified eight (PAH8) priority PAHs as good indicators of the toxicity and occurrence in food. Food supplements containing propolis were also found to contain relatively high quantities of PAHs. We report about an extractive procedure which is able to purify propolis from a high content of PAHs using a balanced mixture of ethanol and water solvents. Extracts were characterised for total content of polyphenols, for in vitro antioxidant activity, and single classes of polyphenols evaluated by HPLC-ESI-MS. Obtained propolis extracts were found to have PAH8 and specific benzo[a]pyrene content below limits recommended by EFSA. The reported extractive procedure is easily applicable for possible industrial productions and may also be adopted to the purification of polyphenols from other plant extracts and natural sources.

Raft cultivation area extraction from high resolution remote sensing imagery by fusing multi-scale region-line primitive association features

NASA Astrophysics Data System (ADS)

Wang, Min; Cui, Qi; Wang, Jie; Ming, Dongping; Lv, Guonian

2017-01-01

In this paper, we first propose several novel concepts for object-based image analysis, which include line-based shape regularity, line density, and scale-based best feature value (SBV), based on the region-line primitive association framework (RLPAF). We then propose a raft cultivation area (RCA) extraction method for high spatial resolution (HSR) remote sensing imagery based on multi-scale feature fusion and spatial rule induction. The proposed method includes the following steps: (1) Multi-scale region primitives (segments) are obtained by image segmentation method HBC-SEG, and line primitives (straight lines) are obtained by phase-based line detection method. (2) Association relationships between regions and lines are built based on RLPAF, and then multi-scale RLPAF features are extracted and SBVs are selected. (3) Several spatial rules are designed to extract RCAs within sea waters after land and water separation. Experiments show that the proposed method can successfully extract different-shaped RCAs from HR images with good performance.

Hollow fiber based affinity selection combined with high performance liquid chromatography-mass spectroscopy for rapid screening lipase inhibitors from lotus leaf.

PubMed

Tao, Yi; Zhang, Yufeng; Wang, Yi; Cheng, Yiyu

2013-06-27

A novel kind of immobilized enzyme affinity selection strategy based on hollow fibers has been developed for screening inhibitors from extracts of medicinal plants. Lipases from porcine pancreas were adsorbed onto the surface of polypropylene hollow fibers to form a stable matrix for ligand fishing, which was called hollow fibers based affinity selection (HF-AS). A variety of factors related to binding capability, including enzyme concentration, incubation time, temperature, buffer pH and ion strength, were optimized using a known lipase inhibitor hesperidin. The proposed approach was applied in screening potential lipase bound ligands from extracts of lotus leaf, followed by rapid characterization of active compounds using high performance liquid chromatography-mass spectrometry. Three flavonoids including quercetin-3-O-β-D-arabinopyranosyl-(1→2)-β-D-galactopyranoside, quercetin-3-O-β-D-glucuronide and kaempferol-3-O-β-d-glucuronide were identified as lipase inhibitors by the proposed HF-AS approach. Our findings suggested that the hollow fiber-based affinity selection could be a rapid and convenient approach for drug discovery from natural products resources. Copyright © 2013 Elsevier B.V. All rights reserved.

Aqueous and Ethanolic Valeriana officinalis Extracts Change the Binding of Ligands to Glutamate Receptors

PubMed Central

Del Valle-Mojica, Lisa M.; Cordero-Hernández, José M.; González-Medina, Giselle; Ramos-Vélez, Igmeris; Berríos-Cartagena, Nairimer; Torres-Hernández, Bianca A.; Ortíz, José G.

2011-01-01

The effects of two valerian extracts (aqueous and hydroalcoholic) were investigated through [3H]Glutamate ([3H]Glu) and [3H]Fluorowillardine ([3H]FW) receptor binding assays using rat synaptic membranes in presence of different receptor ligands. In addition, the extract stability was monitored spectrophotometrically. Both extracts demonstrated interaction with ionotropic glutamate receptors (iGluRs). However, the extracts displayed considerable differences in receptor selectivity. The hydroalcoholic extract selectively interacted with quisqualic acid (QA), group I metabotropic glutamate receptor (mGluR) ligand, while the aqueous extract did not alter the binding of QA. The stability of the extracts was examined during several weeks. Freshly prepared extract inhibited 38–60% of [3H]FW binding (AMPA). After 10 days, the aqueous extract inhibited 85% of [3H]FW binding while the hydroalcoholic extract markedly potentiated (200%) [3H]FW binding to AMPA receptors. Thus, our results showed that factors such as extraction solvent and extract stability determine the selectivity for glutamate receptor (GluR) interactions. PMID:21151614

Aqueous and Ethanolic Valeriana officinalis Extracts Change the Binding of Ligands to Glutamate Receptors.

PubMed

Del Valle-Mojica, Lisa M; Cordero-Hernández, José M; González-Medina, Giselle; Ramos-Vélez, Igmeris; Berríos-Cartagena, Nairimer; Torres-Hernández, Bianca A; Ortíz, José G

2011-01-01

The effects of two valerian extracts (aqueous and hydroalcoholic) were investigated through [(3)H]Glutamate ([(3)H]Glu) and [(3)H]Fluorowillardine ([(3)H]FW) receptor binding assays using rat synaptic membranes in presence of different receptor ligands. In addition, the extract stability was monitored spectrophotometrically. Both extracts demonstrated interaction with ionotropic glutamate receptors (iGluRs). However, the extracts displayed considerable differences in receptor selectivity. The hydroalcoholic extract selectively interacted with quisqualic acid (QA), group I metabotropic glutamate receptor (mGluR) ligand, while the aqueous extract did not alter the binding of QA. The stability of the extracts was examined during several weeks. Freshly prepared extract inhibited 38-60% of [(3)H]FW binding (AMPA). After 10 days, the aqueous extract inhibited 85% of [(3)H]FW binding while the hydroalcoholic extract markedly potentiated (200%) [(3)H]FW binding to AMPA receptors. Thus, our results showed that factors such as extraction solvent and extract stability determine the selectivity for glutamate receptor (GluR) interactions.

Increasing productivity for the analysis of trace contaminants in food by gas chromatography-mass spectrometry using automated liner exchange, backflushing and heart-cutting.

PubMed

David, Frank; Tienpont, Bart; Devos, Christophe; Lerch, Oliver; Sandra, Pat

2013-10-25

Laboratories focusing on residue analysis in food are continuously seeking to increase sample throughput by minimizing sample preparation. Generic sample extraction methods such as QuEChERS lack selectivity and consequently extracts are not free from non-volatile material that contaminates the analytical system. Co-extracted matrix constituents interfere with target analytes, even if highly sensitive and selective GC-MS/MS is used. A number of GC approaches are described that can be used to increase laboratory productivity. These techniques include automated inlet liner exchange and column backflushing for preservation of the performance of the analytical system and heart-cutting two-dimensional GC for increasing sensitivity and selectivity. The application of these tools is illustrated by the analysis of pesticides in vegetables and fruits, PCBs in milk powder and coplanar PCBs in fish. It is demonstrated that considerable increase in productivity can be achieved by decreasing instrument down-time, while analytical performance is equal or better compared to conventional trace contaminant analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

Selective extraction and enrichment of multiphosphorylated peptides using polyarginine-coated diamond nanoparticles.

PubMed

Chang, Chia-Kai; Wu, Chih-Che; Wang, Yi-Sheng; Chang, Huan-Cheng

2008-05-15

Despite recent advances in phosphopeptide research, detection and characterization of multiply phosphorylated peptides have been a challenge. This work presents a new strategy that not only can effectively extract phosphorylated peptides from complex samples but also can selectively enrich multiphosphorylated peptides for direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis. Polyarginine-coated diamond nanoparticles are the solid-phase extraction supports used for this purpose. The supports show an exceptionally high affinity for multiphosphorylated peptides due to multiple arginine-phosphate interactions. The efficacy of this method was demonstrated by analyzing a small volume (50 microL) of tryptic digests of proteins such as beta-casein, alpha-casein, and nonfat milk at a concentration as low as 1 x 10 (-9) M. The concentration is markedly lower than that can be achieved by using other currently available technologies. We quantified the enhanced selectivity and detection sensitivity of the method using mixtures composed of mono- and tetraphosphorylated peptide standards. This new affinity-based protocol is expected to find useful applications in characterizing multiple phosphorylation sites on proteins of interest in complex and dilute analytes.

Selective recovery of vanadium and scandium by ion exchange with D201 and solvent extraction using P507 from hydrochloric acid leaching solution of red mud.

PubMed

Zhu, Xiaobo; Li, Wang; Tang, Sen; Zeng, Majian; Bai, Pengyuan; Chen, Lunjian

2017-05-01

D201 resin and P507 extractant diluted with sulfonated kerosene were used to respectively separate vanadium and scandium, and impurity ions from hydrochloric acid leaching solution of red mud. More than 99% of vanadium was selectively adsorbed from the hydrochloric acid leaching solution under the conditions of pH value of 1.8, volume ratio of leaching solution to resin of 10, and flow rate of 3.33 mL/min. Maximum extraction and separation of scandium was observed from the acid leaching solution at an aqueous pH value of 0.2. More than 99% of scandium can be selectively extracted using 15% P507, 5% TBP at the aqueous solution/organic phase (A/O) ratio of 10:1 for 6 min. The loaded organic phase was washed with 0.3 mol/L sulfuric acid, wherein most impurities were removed. After the process of desorption or stripping, precipitation, and roasting, high-purity V 2 O 5 and Sc 2 O 3 were obtained. Finally, a conceptual flow sheet was established to separate and recover vanadium and scandium from red mud hydrochloric acid leaching solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecularly imprinted polymer for determination of lumefantrine in human plasma through chemometric-assisted solid-phase extraction and liquid chromatography.

PubMed

da Silva, Pedro Henrique Reis; Diniz, Melina Luiza Vieira; Pianetti, Gerson Antônio; da Costa César, Isabela; Ribeiro E Silva, Maria Elisa Scarpelli; de Souza Freitas, Roberto Fernando; de Sousa, Ricardo Geraldo; Fernandes, Christian

2018-07-01

Lumefantrine is the first-choice treatment of Falciparum uncomplicated malaria. Recent findings of resistance to lumefantrine has brought attention for the importance of therapeutic monitoring, since exposure to subtherapeutic doses of antimalarials after administration is a major cause of selection of resistant parasites. Therefore, this study focused on the development of innovative, selective, less expensive and stable molecularly imprinted polymers (MIPs) for solid-phase extraction (SPE) of lumefantrine from human plasma to be used in drug monitoring. Polymers were synthesized by precipitation polymerization and chemometric tools (Box-Behnken design and surface response methodology) were employed for rational optimization of synthetic parameters. Optimum conditions were achieved with 2-vinylpyridine as monomer, ethylene glycol dimethacrylate as crosslinker and toluene as porogen, at molar ratio of 1:6:30 of template/monomer/crosslinker and azo-bisisobutyronitrile as initiator at 65 °C. The MIP obtained was characterized and exhibited high thermal stability, adequate surface morphology and porosity characteristics and high binding properties, with high affinity (adsorption capacity of 977.83 μg g -1 ) and selectivity (imprinting factor of 2.44; and selectivity factor of 1.48 and selectivity constant of 1.44 compared with halofantrine). Doehlert matrix and fractional designs were satisfactorily used for development and optimization of a MISPE-HPLC-UV method for determination of lumefantrine. The method fulfilled all validation parameters, with recoveries ranging from 83.68% to 85.42%, and was applied for quantitation of the drug in plasma from two healthy volunteers, with results of 1407.89 and 1271.35 ng mL -1 , respectively. Therefore, the MISPE-HPLC-UV method optimized through chemometrics provided a rapid, highly selective, less expensive and reproducible approach for lumefantrine drug monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.

Silica/graphene oxide nanocomposites: Potential adsorbents for solid phase extraction of trace aflatoxins in cereal crops coupled with high performance liquid chromatography.

PubMed

Yu, Li; Ma, Fei; Ding, Xiaoxia; Wang, Hengling; Li, Peiwu

2018-04-15

Graphene oxide wrapped silica nanocomposites were synthesized and selected as solid phase extraction adsorbents for high performance liquid chromatography analysis of aflatoxins. The major parameters affecting extraction efficiency were optimized, including the amount of adsorbents, extraction time and desorption conditions. The limit of detections and the limit of quantifications were from 0.1 to 0.3 µg/kg and from 0.3 to 1.0 µg/kg, respectively. The recoveries of aflatoxins in the spiked maize and rice samples were in the range of 76.8-104.7% and 81.1-106.9%, respectively, and with the RSDs less than 12.4%. The proposed method was proven to be simple, rapid and reliable for routine analysis of aflatoxins in crops. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antioxidant White Grape Seed Phenolics: Pressurized Liquid Extracts from Different Varieties

PubMed Central

Garcia-Jares, Carmen; Vazquez, Alberto; Lamas, Juan P.; Pajaro, Marta; Alvarez-Casas, Marta; Lores, Marta

2015-01-01

Grape seeds represent a high percentage (20% to 26%) of the grape marc obtained as a byproduct from white winemaking and keep a vast proportion of grape polyphenols. In this study, seeds obtained from 11 monovarietal white grape marcs cultivated in Northwestern Spain have been analyzed in order to characterize their polyphenolic content and antioxidant activity. Seeds of native (Albariño, Caiño, Godello, Loureiro, Torrontés, and Treixadura) and non-native (Chardonnay, Gewurtzträminer, Pinot blanc, Pinot gris, and Riesling) grape varieties have been considered. Low weight phenolics have been extracted by means of pressurized liquid extraction (PLE) and further analyzed by LC-MS/MS. The results showed that PLE extracts, whatever the grape variety of origin, contained large amounts of polyphenols and high antioxidant activity. Differences in the varietal polyphenolic profiles were found, so a selective exploitation of seeds might be possible. PMID:26783956

Determination of azoxystrobin and chlorothalonil using a methacrylate-based polymer modified with gold nanoparticles as solid-phase extraction sorbent.

PubMed

Catalá-Icardo, Mónica; Gómez-Benito, Carmen; Simó-Alfonso, Ernesto Francisco; Herrero-Martínez, José Manuel

2017-01-01

This paper describes a novel and sensitive method for extraction, preconcentration, and determination of two important widely used fungicides, azoxystrobin, and chlorothalonil. The developed methodology is based on solid-phase extraction (SPE) using a polymeric material functionalized with gold nanoparticles (AuNPs) as sorbent followed by high-performance liquid chromatography (HPLC) with diode array detector (DAD). Several experimental variables that affect the extraction efficiency such as the eluent volume, sample flow rate, and salt addition were optimized. Under the optimal conditions, the sorbent provided satisfactory enrichment efficiency for both fungicides, high selectivity and excellent reusability (>120 re-uses). The proposed method allowed the detection of 0.05 μg L -1 of the fungicides and gave satisfactory recoveries (75-95 %) when it was applied to drinking and environmental water samples (river, well, tap, irrigation, spring, and sea waters).

Selectively Adsorptive Extraction of Phenylarsonic Acids in Chicken Tissue by Carboxymethyl α-Cyclodextrin Immobilized Fe3O4 Magnetic Nanoparticles Followed Ultra Performance Liquid Chromatography Coupled Tandem Mass Spectrometry Detection

PubMed Central

Jia, Jing; Zhang, Wei; Wang, Jing; Wang, Peilong; Zhu, Ruohua

2014-01-01

Carboxymethyl α-cyclodextrin immobilized Fe3O4 magnetic nanoparticles (CM-α-CD-Fe3O4) were synthesized for the selectively adsorptive extraction of five phenylarsonic acids including p-amino phenylarsonic acid, p-nitro phenylarsonic acid, p-hydroxy phenylarsonic acid, p-acylamino phenylarsonic acid and p-hydroxy-3-nitro phenylarsonic acid in chicken tissue. Using ultra performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS), a highly sensitive analytical method was proposed for the determination of five phenylarsonic acids. It was shown that CM-α-CD-Fe3O4 could extract the five phenylarsonic acids in complex chicken tissue samples with high extraction efficiency. Under the optimal conditions, a high enrichment factor, ranging from 349 to 606 fold, was obtained. The limits of detection (LODs) (at a signal-to-noise ratio of 3) were in the range of 0.05–0.11 µg/kg for the five phenylarsonic acids. The proposed method was applied for the determination of five target phenylarsonic acids in chicken muscle and liver samples. Recoveries for the spiked samples with 0.2 µg/kg, 2.0 µg/kg and 20 µg/kg of each phenylarsonic acids were in the range of 77.2%–110.2%, with a relative standard deviation (RSD) of less than 12.5%. PMID:25215503

Assessing ligand selectivity for uranium over vanadium ions to aid in the discovery of superior adsorbents for extraction of UO 2 2+ from seawater

DOE PAGES

Ivanov, Alexander S.; Bryantsev, Vyacheslav S.

2016-06-06

Uranium is used as the basic fuel for nuclear power plants, which generate significant amounts of electricity and have life cycle carbon emissions that are as low as renewable energy sources. However, the extraction of this valuable energy commodity from the ground remains controversial, mainly because of environmental and health impacts. Alternatively, seawater offers an enormous uranium resource that may be tapped at minimal environmental cost. Nowadays, amidoxime polymers are the most widely utilized sorbent materials for large-scale extraction of uranium from seawater, but they are not perfectly selective for uranyl, UO 2 2+. In particular, the competition between UOmore » 2 2+ and VO 2+/VO2+ cations poses a significant challenge to the effi-cient mining of UO 2 2+. Thus, screening and rational design of more selective ligands must be accomplished. One of the key components in achieving this goal is the establishment of computational techniques capable of assessing ligand selec-tivity trends. Here, we report an approach based on quantum chemical calculations that achieves high accuracy in repro-ducing experimental aqueous stability constants for VO 2+/VO 2+ complexes with ten different oxygen donor lig-ands. The predictive power of the developed computational protocol was demonstrated for amidoxime-type ligands, providing greater insights into new design strategies for the development of the next generation of adsorbents with high selectivity toward UO 2 2+over VO 2+/VO 2+ ions. Furthermore, the results of calculations suggest that alkylation of amidox-ime moieties present in poly(acrylamidoxime) sorbents can be a potential route to better discrimination between the uranyl and competing vanadium ions within seawater.« less

Green technology approach towards herbal extraction method

NASA Astrophysics Data System (ADS)

Mutalib, Tengku Nur Atiqah Tengku Ab; Hamzah, Zainab; Hashim, Othman; Mat, Hishamudin Che

2015-05-01

The aim of present study was to compare maceration method of selected herbs using green and non-green solvents. Water and d-limonene are a type of green solvents while non-green solvents are chloroform and ethanol. The selected herbs were Clinacanthus nutans leaf and stem, Orthosiphon stamineus leaf and stem, Sesbania grandiflora leaf, Pluchea indica leaf, Morinda citrifolia leaf and Citrus hystrix leaf. The extracts were compared with the determination of total phenolic content. Total phenols were analyzed using a spectrophotometric technique, based on Follin-ciocalteau reagent. Gallic acid was used as standard compound and the total phenols were expressed as mg/g gallic acid equivalent (GAE). The most suitable and effective solvent is water which produced highest total phenol contents compared to other solvents. Among the selected herbs, Orthosiphon stamineus leaves contain high total phenols at 9.087mg/g.

Fabric phase sorptive extraction: Two practical sample pretreatment techniques for brominated flame retardants in water.

PubMed

Huang, Guiqi; Dong, Sheying; Zhang, Mengfei; Zhang, Haihan; Huang, Tinglin

2016-09-15

Sample pretreatment is the critical section for residue monitoring of hazardous pollutants. In this paper, using the cellulose fabric as host matrix, three extraction sorbents such as poly (tetrahydrofuran) (PTHF), poly (ethylene glycol) (PEG) and poly (dimethyldiphenylsiloxane) (PDMDPS), were prepared on the surface of the cellulose fabric. Two practical extraction techniques including stir bar fabric phase sorptive extraction (stir bar-FPSE) and magnetic stir fabric phase sorptive extraction (magnetic stir-FPSE) have been designed, which allow stirring of fabric phase sorbent during the whole extraction process. In the meantime, three brominated flame retardants (BFRs) [tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bisallylether (TBBPA-BAE), tetrabromobisphenol A bis(2,3-dibromopropyl)ether (TBBPA-BDBPE)] in the water sample were selected as model analytes for the practical evaluation of the proposed two techniques using high-performance liquid chromatography (HPLC). Moreover, various experimental conditions affecting extraction process such as the type of fabric phase, extraction time, the amount of salt and elution conditions were also investigated. Due to the large sorbent loading capacity and unique stirring performance, both techniques possessed high extraction capability and fast extraction equilibrium. Under the optimized conditions, high recoveries (90-99%) and low limits of detection (LODs) (0.01-0.05 μg L(-1)) were achieved. In addition, the reproducibility was obtained by evaluating the intraday and interday precisions with relative standard deviations (RSDs) less than 5.1% and 6.8%, respectively. The results indicated that two pretreatment techniques were promising and practical for monitoring of hazardous pollutants in the water sample. Due to low solvent consumption and high repeated use performance, proposed techniques also could meet green analytical criteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Detection of goal events in soccer videos

NASA Astrophysics Data System (ADS)

Kim, Hyoung-Gook; Roeber, Steffen; Samour, Amjad; Sikora, Thomas

2005-01-01

In this paper, we present an automatic extraction of goal events in soccer videos by using audio track features alone without relying on expensive-to-compute video track features. The extracted goal events can be used for high-level indexing and selective browsing of soccer videos. The detection of soccer video highlights using audio contents comprises three steps: 1) extraction of audio features from a video sequence, 2) event candidate detection of highlight events based on the information provided by the feature extraction Methods and the Hidden Markov Model (HMM), 3) goal event selection to finally determine the video intervals to be included in the summary. For this purpose we compared the performance of the well known Mel-scale Frequency Cepstral Coefficients (MFCC) feature extraction method vs. MPEG-7 Audio Spectrum Projection feature (ASP) extraction method based on three different decomposition methods namely Principal Component Analysis( PCA), Independent Component Analysis (ICA) and Non-Negative Matrix Factorization (NMF). To evaluate our system we collected five soccer game videos from various sources. In total we have seven hours of soccer games consisting of eight gigabytes of data. One of five soccer games is used as the training data (e.g., announcers' excited speech, audience ambient speech noise, audience clapping, environmental sounds). Our goal event detection results are encouraging.

Instrument for Solvent Extraction and Analysis (ISEE) of Organics from Regolith Simulant Using Supercritical Fluid Extraction and Chromatography

NASA Technical Reports Server (NTRS)

Franco, Carolina; Hintze, Paul E.

2017-01-01

ISEE is an instrument with the potential to perform extractions from regolith found on the surface of asteroids and planets, followed by characterization and quantitation of the extracts using supercritical fluid extraction (SFE) and chromatography (SFC). SFE is a developed technique proven to extract a wide range of organic compounds. SFC is similar to High Performance Liquid Chromatography (HPLC) but has the advantage of performing chiral separations without needing to derivatize the chiral compounds. CO2 will be the solvent for both stages as it is readily available in the Mars atmosphere. ISEE will capture CO2 from the environment, and use it for SFE and SFC. If successful, this would allow ISEE to perform analysis of organic compounds without using consumables. This paper will present results on a preliminary, proof-of-principle effort to use SFE and SFC to extract and analyze lunar regolith simulant spiked with organic compounds representing a range of organics that ISEE would expect to characterize. An optimization of variables for the extraction of the organics from the spiked regolith was successfully developed, using 138 bar pressure and 40 C temperature. The extraction flow rate was optimized at 2% SLPM with 30% methanol modifier. The extractions were successful with a value of 77.3+/- 0.9% of organics extracted. However, the recovery of organics after the extraction was very low with only 48.5+/-14.2%. Moreover, three columns were selected to analyze multiple samples at a time; two of them are Viridis HSS C18 SB and Torus DIOL, and the third column, specific for chiral separations, has not yet been selected yet.

A supported liquid membrane system for the selective recovery of rare earth elements from neodymium-based permanent magnets

DOE PAGES

Kim, Daejin; Powell, Lawrence; Delmau, Lætitia H.; ...

2016-04-04

We present that the rare earth elements (REEs) play a vital role in the development of green energy and high-tech industries. In order to meet the fast-growing demand and to ensure sufficient supply of the REEs, it is essential to develop an efficient REE recovery process from post-consumer REE-containing products. In this research effort, we have developed a supported liquid membrane system utilizing polymeric hollow fiber modules to extract REEs from neodymium-based magnets with neutral extractants such as tetraoctyl digylcol amide (TODGA). The effect of process variables such as REE concentration, molar concentration of acid, and membrane area on REEmore » recovery was investigated. We have demonstrated the selective extraction and recovery of REEs such as Nd, Pr, and Dy without co-extraction of non-REEs from permanent NdFeB magnets through the supported liquid membrane system. The extracted REEs were then recovered by precipitation followed by the annealing step to obtain crystalline REE powders in nearly pure form. Finally, the recovered REE oxides were characterized by X-ray diffraction, scanning electron microscope coupled with energy-dispersive X-ray spectroscopy, and inductively coupled plasma–optical emission spectroscopy.« less

Anti-inflammatory, cyclooxygenase (COX)-2, COX-1 inhibitory, and free radical scavenging effects of Rumex nepalensis.

PubMed

Gautam, Raju; Karkhile, Kailas V; Bhutani, Kamlesh K; Jachak, Sanjay M

2010-10-01

Evaluation of the topical anti-inflammatory activity of chloroform and ethyl acetate extracts of RUMEX NEPALENSIS roots in a TPA-induced acute inflammation mouse model demonstrated a significant reduction in ear edema. The extracts were further tested on purified enzymes for COX-1 and COX-2 inhibition to elucidate their mechanism of action, and a strong inhibition was observed. Six anthraquinones and two naphthalene derivatives were isolated from the ethyl acetate extract. Among the isolated compounds, emodin was found to be a potent inhibitor with slight selectivity towards COX-2, and nepodin exhibited selectivity towards COX-1. Emodin, endocrocin, and nepodin also exhibited significant topical anti-inflammatory activity in mice. Interestingly, nepodin showed better radical scavenging activity than trolox and ascorbic acid against DPPH and ABTS radicals. The strong radical scavenging activity of chloroform and ethyl acetate extracts could be explained by the presence of nepodin as well as by the high phenolic content of the ethyl acetate extract. Thus, the anti-inflammatory effect of R. NEPALENSIS roots was assumed to be mediated through COX inhibition by anthraquinones and naphthalene derivatives and through the radical scavenging activities of naphthalene derivatives. © Georg Thieme Verlag KG Stuttgart · New York.

Bioaccessibility in vitro of nutraceuticals from bark of selected Salix species.

PubMed

Gawlik-Dziki, Urszula; Sugier, Danuta; Dziki, Dariusz; Sugier, Piotr

2014-01-01

The aim of this study was to investigate and to compare the extractability, bioaccessibility, and bioavailability in vitro of antioxidative compounds from bark of selected Salix species: S. alba (SA), S. daphnoides (SD), S. purpurea (SP), and S. daphnoides x purpurea (SDP) hybrid willow clones originating from their natural habitats and cultivated on the sandy soil. The highest amount of phenolic glycosides was found in the bark of SDP and SD. The best source of phenolics was bark of SDP. The highest content of flavonoids were found in SD bark samples, whereas the highest concentration of bioaccessible and bioavailable phenolic acids was determined in SDP bark. Bark of all tested Salix species showed significant antiradical activity. This properties are strongly dependent on extraction system and genetic factors. Regardless of Salix genotypes, the lowest chelating power was found for chemically-extractable compounds. Bark of all Salix species contained ethanol-extractable compounds with reducing ability. Besides this, high bioaccessibility and bioavailability in vitro of Salix bark phytochemicals were found. Obtained results indicate that extracts from bark tested Salix genotypes can provide health promoting benefits to the consumers; however, this problem requires further study.

Bioaccessibility In Vitro of Nutraceuticals from Bark of Selected Salix Species

PubMed Central

2014-01-01

The aim of this study was to investigate and to compare the extractability, bioaccessibility, and bioavailability in vitro of antioxidative compounds from bark of selected Salix species: S. alba (SA), S. daphnoides (SD), S. purpurea (SP), and S. daphnoides x purpurea (SDP) hybrid willow clones originating from their natural habitats and cultivated on the sandy soil. The highest amount of phenolic glycosides was found in the bark of SDP and SD. The best source of phenolics was bark of SDP. The highest content of flavonoids were found in SD bark samples, whereas the highest concentration of bioaccessible and bioavailable phenolic acids was determined in SDP bark. Bark of all tested Salix species showed significant antiradical activity. This properties are strongly dependent on extraction system and genetic factors. Regardless of Salix genotypes, the lowest chelating power was found for chemically-extractable compounds. Bark of all Salix species contained ethanol-extractable compounds with reducing ability. Besides this, high bioaccessibility and bioavailability in vitro of Salix bark phytochemicals were found. Obtained results indicate that extracts from bark tested Salix genotypes can provide health promoting benefits to the consumers; however, this problem requires further study. PMID:24696660

SD-MSAEs: Promoter recognition in human genome based on deep feature extraction.

PubMed

Xu, Wenxuan; Zhang, Li; Lu, Yaping

2016-06-01

The prediction and recognition of promoter in human genome play an important role in DNA sequence analysis. Entropy, in Shannon sense, of information theory is a multiple utility in bioinformatic details analysis. The relative entropy estimator methods based on statistical divergence (SD) are used to extract meaningful features to distinguish different regions of DNA sequences. In this paper, we choose context feature and use a set of methods of SD to select the most effective n-mers distinguishing promoter regions from other DNA regions in human genome. Extracted from the total possible combinations of n-mers, we can get four sparse distributions based on promoter and non-promoters training samples. The informative n-mers are selected by optimizing the differentiating extents of these distributions. Specially, we combine the advantage of statistical divergence and multiple sparse auto-encoders (MSAEs) in deep learning to extract deep feature for promoter recognition. And then we apply multiple SVMs and a decision model to construct a human promoter recognition method called SD-MSAEs. Framework is flexible that it can integrate new feature extraction or new classification models freely. Experimental results show that our method has high sensitivity and specificity. Copyright © 2016 Elsevier Inc. All rights reserved.

High individual variation in pheromone production by tree-killing bark beetles (Coleoptera: Curculionidae: Scolytinae)

NASA Astrophysics Data System (ADS)

Pureswaran, Deepa S.; Sullivan, Brian T.; Ayres, Matthew P.

2008-01-01

Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature.

Production of secondary metabolites by some terverticillate penicillia on carbohydrate-rich and meat substrates.

PubMed

Núñez, Félix; Westphal, Carmen D; Bermúdez, Elena; Asensio, Miguel A

2007-12-01

Most terverticillate penicillia isolated from dry-cured meat products are toxigenic, but their ability to produce hazardous metabolites on meat-based substrates is not well known. The production of extrolites by selected terverticillate penicillia isolated from dry-cured ham has been studied on carbohydrate-rich media (malt extract agar, Czapek yeast autolysate agar, rice extract agar, and rice), meat extract triolein salt agar, and ham slices. Chloroform extracts from the selected strains grown on malt extract agar were toxic for the brine shrimp (Artemia salina) larvae and VERO cells at a concentration of 2 mg/ml, but 0.02 mg/ml produced no toxic effect. Analysis by high-pressure liquid chromatography (HPLC) coupled with photodiode array detection (DAD) or with mass spectrometry (MS) and an atmospheric pressure chemical ionization (APCI) source revealed different biologically active metabolites: cyclopiazonic acid and rugulovasine A from Penicillium commune; verrucosidin, anacine, puberuline, verrucofortine, and viridicatols from Penicillium polonicum; arisugacin and viridicatols from Penicillium echinulatum; and compactin and viridicatols from Penicillium solitum. Most of these metabolites, including the amino acid-derived compounds, were produced in the media containing high levels of carbohydrates. High concentrations of nitrogen compounds in the medium does not imply a greater production of the metabolites studied, not even those derived from the amino acids. However, molds growing on dry-cured ham are able to synthesize limited amounts of some secondary metabolites, a fact not previously reported. The combination of HPLC coupled with DAD and MS-APCI was useful for identification of closely related terverticillate Penicillium species from dry-cured ham. These techniques could be used to characterize the risk associated with the potential production of secondary metabolites in cured meats.

Extraction Selectivity of a Quaternary Alkylammonium Salt for Trivalent Actinides over Trivalent Lanthanides: Does Extractant Aggregation Play a Role?

DOE PAGES

Knight, Andrew W.; Chiarizia, Renato; Soderholm, L.

2017-05-10

In this paper, the extraction behavior of a quaternary alkylammonium salt extractant was investigated for its selectivity for trivalent actinides over trivalent lanthanides in nitrate and thiocyanate media. The selectivity was evaluated by solvent extraction experiments through radiochemical analysis of 241Am and 152/154Eu. Solvent extraction distribution and slope-analysis experiments were performed with americium(III) and europium(III) with respect to the ligand (nitrate and thiocyanate), extractant, and metal (europium only) concentrations. Further evaluation of the equilibrium expression that governs the extraction process indicated the appropriate use of the saturation method for estimation of the aggregation state of quaternary ammonium extractants in themore » organic phase. From the saturation method, we observed an average aggregation number of 5.4 ± 0.8 and 8.5 ± 0.9 monomers/aggregate for nitrate and thiocyanate, respectively. Through a side-by-side comparison of the nitrate and thiocyanate forms, we discuss the potential role of the aggregation in the increased selectivity for trivalent actinides over trivalent lanthanides in thiocyanate media.« less

Extraction Selectivity of a Quaternary Alkylammonium Salt for Trivalent Actinides over Trivalent Lanthanides: Does Extractant Aggregation Play a Role?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knight, Andrew W.; Chiarizia, Renato; Soderholm, L.

In this paper, the extraction behavior of a quaternary alkylammonium salt extractant was investigated for its selectivity for trivalent actinides over trivalent lanthanides in nitrate and thiocyanate media. The selectivity was evaluated by solvent extraction experiments through radiochemical analysis of 241Am and 152/154Eu. Solvent extraction distribution and slope-analysis experiments were performed with americium(III) and europium(III) with respect to the ligand (nitrate and thiocyanate), extractant, and metal (europium only) concentrations. Further evaluation of the equilibrium expression that governs the extraction process indicated the appropriate use of the saturation method for estimation of the aggregation state of quaternary ammonium extractants in themore » organic phase. From the saturation method, we observed an average aggregation number of 5.4 ± 0.8 and 8.5 ± 0.9 monomers/aggregate for nitrate and thiocyanate, respectively. Through a side-by-side comparison of the nitrate and thiocyanate forms, we discuss the potential role of the aggregation in the increased selectivity for trivalent actinides over trivalent lanthanides in thiocyanate media.« less

High-capacity thermo-responsive magnetic molecularly imprinted polymers for selective extraction of curcuminoids.

PubMed

You, Qingping; Zhang, Yuping; Zhang, Qingwen; Guo, Junfang; Huang, Weihua; Shi, Shuyun; Chen, Xiaoqin

2014-08-08

Thermo-responsive magnetic molecularly imprinted polymers (TMMIPs) for selective recognition of curcuminoids with high capacity and selectivity have firstly been developed. The resulting TMMIPs were characterized by TEM, FT-IR, TGA, VSM and UV, which indicated that TMMIPs showed thermo-responsiveness [lower critical solution temperature (LCST) at 33.71°C] and rapid magnetic separation (5s). The polymerization, adsorption and release conditions were optimized in detail to obtain the highest binding capacity, selectivity and release ratio. We found that the adopted thermo-responsive monomer [N-isopropylacrylamide (NIPAm)] could be considered not only as inert polymer backbone for thermo-responsiveness but also as functional co-monomers combination with basic monomer (4-VP) for more specific binding sites when ethanol was added in binding solution. The maximum adsorption capacity with highest selectivity of curcumin was 440.3μg/g (1.93 times that on MMIPs with no thermosensitivity) at 45°C (above LCST) in 20% (v/v) ethanol solution on shrunk TMMIPs, and the maximum release proportion was about 98% at 20°C (below LCST) in methanol-acetic acid (9/1, v/v) solution on swelled TMMIPs. The adsorption process between curcumin and TMMIPs followed Langumuir adsorption isotherm and pseudo-first-order reaction kinetics. The prepared TMMIPs also showed high reproducibility (RSD<6% for batch-to-batch evaluation) and stability (only 7% decrease after five cycles). Subsequently, the TMMIPs were successfully applied for selective extraction of curcuminoids from complex natural product, Curcuma longa. Copyright © 2014 Elsevier B.V. All rights reserved.

Learning from Past Classification Errors: Exploring Methods for Improving the Performance of a Deep Learning-based Building Extraction Model through Quantitative Analysis of Commission Errors for Optimal Sample Selection

NASA Astrophysics Data System (ADS)

Swan, B.; Laverdiere, M.; Yang, L.

2017-12-01

In the past five years, deep Convolutional Neural Networks (CNN) have been increasingly favored for computer vision applications due to their high accuracy and ability to generalize well in very complex problems; however, details of how they function and in turn how they may be optimized are still imperfectly understood. In particular, their complex and highly nonlinear network architecture, including many hidden layers and self-learned parameters, as well as their mathematical implications, presents open questions about how to effectively select training data. Without knowledge of the exact ways the model processes and transforms its inputs, intuition alone may fail as a guide to selecting highly relevant training samples. Working in the context of improving a CNN-based building extraction model used for the LandScan USA gridded population dataset, we have approached this problem by developing a semi-supervised, highly-scalable approach to select training samples from a dataset of identified commission errors. Due to the large scope this project, tens of thousands of potential samples could be derived from identified commission errors. To efficiently trim those samples down to a manageable and effective set for creating additional training sample, we statistically summarized the spectral characteristics of areas with rates of commission errors at the image tile level and grouped these tiles using affinity propagation. Highly representative members of each commission error cluster were then used to select sites for training sample creation. The model will be incrementally re-trained with the new training data to allow for an assessment of how the addition of different types of samples affects the model performance, such as precision and recall rates. By using quantitative analysis and data clustering techniques to select highly relevant training samples, we hope to improve model performance in a manner that is resource efficient, both in terms of training process and in sample creation.

Automation of ⁹⁹Tc extraction by LOV prior ICP-MS detection: application to environmental samples.

PubMed

Rodríguez, Rogelio; Leal, Luz; Miranda, Silvia; Ferrer, Laura; Avivar, Jessica; García, Ariel; Cerdà, Víctor

2015-02-01

A new, fast, automated and inexpensive sample pre-treatment method for (99)Tc determination by inductively coupled plasma-mass spectrometry (ICP-MS) detection is presented. The miniaturized approach is based on a lab-on-valve (LOV) system, allowing automatic separation and preconcentration of (99)Tc. Selectivity is provided by the solid phase extraction system used (TEVA resin) which retains selectively pertechnetate ion in diluted nitric acid solution. The proposed system has some advantages such as minimization of sample handling, reduction of reagents volume, improvement of intermediate precision and sample throughput, offering a significant decrease of both time and cost per analysis in comparison to other flow techniques and batch methods. The proposed LOV system has been successfully applied to different samples of environmental interest (water and soil) with satisfactory recoveries, between 94% and 98%. The detection limit (LOD) of the developed method is 0.005 ng. The high durability of the resin and its low amount (32 mg), its good intermediate precision (RSD 3.8%) and repeatability (RSD 2%) and its high extraction frequency (up to 5 h(-1)) makes this method an inexpensive, high precision and fast tool for monitoring (99)Tc in environmental samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Deep sequencing in library selection projects: what insight does it bring?

PubMed

Glanville, J; D'Angelo, S; Khan, T A; Reddy, S T; Naranjo, L; Ferrara, F; Bradbury, A R M

2015-08-01

High throughput sequencing is poised to change all aspects of the way antibodies and other binders are discovered and engineered. Millions of available sequence reads provide an unprecedented sampling depth able to guide the design and construction of effective, high quality naïve libraries containing tens of billions of unique molecules. Furthermore, during selections, high throughput sequencing enables quantitative tracing of enriched clones and position-specific guidance to amino acid variation under positive selection during antibody engineering. Successful application of the technologies relies on specific PCR reagent design, correct sequencing platform selection, and effective use of computational tools and statistical measures to remove error, identify antibodies, estimate diversity, and extract signatures of selection from the clone down to individual structural positions. Here we review these considerations and discuss some of the remaining challenges to the widespread adoption of the technology. Copyright © 2015 Elsevier Ltd. All rights reserved.

Deep sequencing in library selection projects: what insight does it bring?

PubMed Central

Glanville, J; D’Angelo, S; Khan, T.A.; Reddy, S. T.; Naranjo, L.; Ferrara, F.; Bradbury, A.R.M.

2015-01-01

High throughput sequencing is poised to change all aspects of the way antibodies and other binders are discovered and engineered. Millions of available sequence reads provide an unprecedented sampling depth able to guide the design and construction of effective, high quality naïve libraries containing tens of billions of unique molecules. Furthermore, during selections, high throughput sequencing enables quantitative tracing of enriched clones and position-specific guidance to amino acid variation under positive selection during antibody engineering. Successful application of the technologies relies on specific PCR reagent design, correct sequencing platform selection, and effective use of computational tools and statistical measures to remove error, identify antibodies, estimate diversity, and extract signatures of selection from the clone down to individual structural positions. Here we review these considerations and discuss some of the remaining challenges to the widespread adoption of the technology. PMID:26451649

Progress on lipid extraction from wet algal biomass for biodiesel production.

PubMed

Ghasemi Naghdi, Forough; González González, Lina M; Chan, William; Schenk, Peer M

2016-11-01

Lipid recovery and purification from microalgal cells continues to be a significant bottleneck in biodiesel production due to high costs involved and a high energy demand. Therefore, there is a considerable necessity to develop an extraction method which meets the essential requirements of being safe, cost-effective, robust, efficient, selective, environmentally friendly, feasible for large-scale production and free of product contamination. The use of wet concentrated algal biomass as a feedstock for oil extraction is especially desirable as it would avoid the requirement for further concentration and/or drying. This would save considerable costs and circumvent at least two lengthy processes during algae-based oil production. This article provides an overview on recent progress that has been made on the extraction of lipids from wet algal biomass. The biggest contributing factors appear to be the composition of algal cell walls, pre-treatments of biomass and the use of solvents (e.g. a solvent mixture or solvent-free lipid extraction). We compare recently developed wet extraction processes for oleaginous microalgae and make recommendations towards future research to improve lipid extraction from wet algal biomass. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

[Determination by high performance chromatography, steroid saponins in a biologically active food supplements containing the extract of Tribulus terrestris].

PubMed

Kozlova, O I; Perederiaev, O I; Ramenskaia, G V

2011-01-01

Steroidal saponins are bioactive substances of Tribulus terrestris and can be used to assess the quality of raw materials and processed products from them. For this purpose has been developed the method of qualitative and quantitative determination of steroidal saponins by high performance liquid chromatography with spectrophotometric and mass-selective detection and optimal conditions of sample preparation (70% methanol extraction with sonication and heating); also has been studied steroidal saponins composition of Tribulus terrestris (protodioscin, tribulosaponin B, metilprotodiostsin, terrestrozin H, prototribestin, gracillin and others were found).

Advanced functional materials in solid phase extraction for ICP-MS determination of trace elements and their species - A review.

PubMed

He, Man; Huang, Lijin; Zhao, Bingshan; Chen, Beibei; Hu, Bin

2017-06-22

For the determination of trace elements and their species in various real samples by inductively coupled plasma mass spectrometry (ICP-MS), solid phase extraction (SPE) is a commonly used sample pretreatment technique to remove complex matrix, pre-concentrate target analytes and make the samples suitable for subsequent sample introduction and measurements. The sensitivity, selectivity/anti-interference ability, sample throughput and application potential of the methodology of SPE-ICP-MS are greatly dependent on SPE adsorbents. This article presents a general overview of the use of advanced functional materials (AFMs) in SPE for ICP-MS determination of trace elements and their species in the past decade. Herein the AFMs refer to the materials featuring with high adsorption capacity, good selectivity, fast adsorption/desorption dynamics and satisfying special requirements in real sample analysis, including nanometer-sized materials, porous materials, ion imprinting polymers, restricted access materials and magnetic materials. Carbon/silica/metal/metal oxide nanometer-sized adsorbents with high surface area and plenty of adsorption sites exhibit high adsorption capacity, and porous adsorbents would provide more adsorption sites and faster adsorption dynamics. The selectivity of the materials for target elements/species can be improved by using physical/chemical modification, ion imprinting and restricted accessed technique. Magnetic adsorbents in conventional batch operation offer unique magnetic response and high surface area-volume ratio which provide a very easy phase separation, greater extraction capacity and efficiency over conventional adsorbents, and chip-based magnetic SPE provides a versatile platform for special requirement (e.g. cell analysis). The performance of these adsorbents for the determination of trace elements and their species in different matrices by ICP-MS is discussed in detail, along with perspectives and possible challenges in the future development. Copyright © 2017 Elsevier B.V. All rights reserved.

Combination of counterpropagation artificial neural networks and antioxidant activities for comprehensive evaluation of associated-extraction efficiency of various cyclodextrins in the traditional Chinese formula Xue-Zhi-Ning.

PubMed

Sun, Lili; Yang, Jianwen; Wang, Meng; Zhang, Huijie; Liu, Yanan; Ren, Xiaoliang; Qi, Aidi

2015-11-10

Xue-Zhi-Ning (XZN) is a widely used traditional Chinese medicine formula to treat hyperlipidemia. Recently, cyclodextrins (CDs) have been extensively used to minimize problems relative to medicine bioavailability, such as low solubility and poor stability. The objective of this study was to determine the associated-extraction efficiency of various CDs in XZN. Three various type CDs were evaluated, including native CDs (α-CD, β-CD), hydrophilic CD derivatives (HP-β-CD and Me-β-CD), and ionic CD derivatives (SBE-β-CD and CM-β-CD). An ultra high-performance liquid chromatography (UHPLC) fingerprint was applied to determine the components in CD extracts and original aqueous extract (OAE). A counterpropagation artificial neural network (CP-ANN) was used to analyze the components in different extracts and compare the selective extraction of various CDs. Extraction efficiencies of the various CDs in terms of extracted components follow the ranking, ionic CD derivatives>hydrophilic CD derivatives>native CDs>OAE. Besides, different types of CDs have their own selective extraction and ionic CD derivatives present the strongest associated-extraction efficiency. Antioxidant potentials of various extracts were evaluated by determining the inhibition of spontaneous, H2O2-induced, CCl4-induced and Fe(2+)/ascorbic acid-induced lipid peroxidation (LPO) and analyzing the scavenging capacity for DPPH and hydroxyl radicals. The order of extraction efficiencies of the various CDs relative to antioxidant activities is as follows: SBE-β-CD>CM-β-CD>HP-β-CD>Me-β-CD>β-CD>α-CD. It can be demonstrated that all of the CDs studied increase the extraction efficiency and that ionic CD derivatives (SBE-β-CD and CM-β-CD) present the highest extraction capability in terms of amount extracted and antioxidant activities of extracts. Copyright © 2015 Elsevier B.V. All rights reserved.

Mechanism of herpes simplex virus type 2 suppression by propolis extracts.

PubMed

Nolkemper, Silke; Reichling, Jürgen; Sensch, Karl Heinz; Schnitzler, Paul

2010-02-01

Genital herpes caused by herpes simplex virus type 2 (HSV-2) is a chronic, persistent infection spreading efficiently and silently as sexually transmitted disease through the population. Antiviral agents currently applied for the treatment of herpesvirus infections include acyclovir and derivatives. Aqueous and ethanolic extracts of propolis were phytochemically analysed, different polyphenols, flavonoids and phenylcarboxylic acids were identified as major constituents. The aqueous propolis extract revealed a relatively high amount of phenylcarboxylic acids and low concentrations flavonoids when compared to the ethanolic special extract GH 2002. The cytotoxic and antiherpetic effect of propolis extracts against HSV-2 was analysed in cell culture, and revealed a moderate cytotoxicity on RC-37 cells. The 50% inhibitory concentration (IC(50)) of aqueous and ethanolic GH 2002 propolis extracts for HSV-2 plaque formation was determined at 0.0005% and 0.0004%, respectively. Both propolis extracts exhibited high levels of antiviral activity against HSV-2 in viral suspension tests, infectivity was significantly reduced by >99% and a direct concentration- and time-dependent antiherpetic activity could be demonstrated for both extracts. In order to determine the mode of virus suppression by propolis, the extracts were added at different times during the viral infection cycle. Addition of these drugs to uninfected cells prior to infection or to herpesvirus-infected cells during intracellular replication had no effect on virus multiplication. However both propolis extracts exhibited high anti-herpetic activity when viruses were pretreated with these drugs prior to infection. Selectivity indices were determined at 80 and 42.5 for the aqueous and ethanolic extract, respectively, thus propolis extracts might be suitable for topical therapy in recurrent herpetic infection. Copyright 2009 Elsevier GmbH. All rights reserved.

Advanced solvent based methods for molecular characterization of soil organic matter by high-resolution mass spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tfaily, Malak M.; Chu, Rosalie K.; Tolic, Nikola

2015-05-19

Soil organic matter (SOM) a complex, heterogeneous mixture of above and belowground plant litter and animal and microbial residues at various degrees of decomposition, is a key reservoir for carbon (C) and nutrient biogeochemical cycling in soil based ecosystems. A limited understanding of the molecular composition of SOM limits the ability to routinely decipher chemical processes within soil and predict accurately how terrestrial carbon fluxes will response to changing climatic conditions and land use. To elucidate the molecular-level structure of SOM, we selectively extracted a broad range of intact SOM compounds by a combination of different organic solvents from soilsmore » with a wide range of C content. Our use of Electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and a suite of solvents with varying polarity significantly expands the inventory of the types of organic molecules present in soils. Specifically, we found that hexane is selective for lipid-like compounds with very low O:C ratios; water was selective for carbohydrates with high O:C ratios; acetonitrile preferentially extracts lignin, condensed structures, and tannin poly phenolic compounds with O:C > 0.5; methanol has higher selectivity towards compounds characterized with low O:C < 0.5; and hexane, MeOH, ACN and water solvents increase the number and types of organic molecules extracted from soil for a broader range of chemically diverse soil types. Our study of SOM molecules by ESI-FTICR MS revealed new insight into the molecular-level complexity of organics contained in soils.« less

Efficient Removal of Arsenic and Antimony During Blast Furnace Smelting of Lead-Containing Materials

NASA Astrophysics Data System (ADS)

Dosmukhamedov, Nurlan; Kaplan, Valery

2017-02-01

The efficient removal of impurities, As and Sb, from recycled lead-containing materials is a key issue in the selection of the appropriate smelting technology for projects involving metal reuse. Volatilization of impurities such as As and Sb should occur as early as possible in the process, and preferably within the smelting furnace, so that they do not contaminate the industrial environment nor interfere with the operation of downstream equipment. Using of copper-zinc concentrates in the blast furnace process for recycling lead-containing materials achieves: (1) high copper extraction to matte; (2) high lead extraction to lead bullion; and (3) high zinc extraction to slag, while at the same time producing a more efficient volatilization of As and Sb. Based on both laboratory and industrial data and thermodynamic considerations, the advantages of this blast furnace process for the treatment of recycled lead-containing materials are discussed.

Quality of reporting and risk of bias in therapeutic otolaryngology publications.

PubMed

Kaper, N M; Swart, K M A; Grolman, W; Van Der Heijden, G J M G

2018-01-01

High-quality trials have the potential to influence clinical practice. Ten otolaryngology journals with the highest 2011 impact factors were selected and publications from 2010 were extracted. From all medical journals, the 20 highest impact factor journals were selected, and publications related to otolaryngology for 2010 and 2011 were extracted. For all publications, the reporting quality and risk of bias were assessed. The impact factor was 1.8-2.8 for otolaryngology journals and 6.0-101.8 for medical journals. Of 1500 otolaryngology journal articles, 262 were therapeutic studies; 94 had a high reporting quality and 5 a low risk of bias. Of 10 967 medical journal articles, 76 were therapeutic studies; 57 had a high reporting quality and 8 a low risk of bias. Reporting quality was high for 45 per cent of otolaryngology-related publications and 9 per cent met quality standards. General journals had higher impact factors than otolaryngology journals. Reporting quality was higher and risk of bias lower in general journals than in otolaryngology journals. Nevertheless, 76 per cent of articles in high impact factor journals carried a high risk of bias. Better reported and designed studies are the goal, with less risk of bias, especially in otolaryngology journals.

Molecularly imprinted microspheres synthesized by a simple, fast, and universal suspension polymerization for selective extraction of the topical anesthetic benzocaine in human serum and fish tissues.

PubMed

Sun, Hui; Lai, Jia-Ping; Chen, Fang; Zhu, De-Rong

2015-02-01

A simple, fast, and universal suspension polymerization method was used to synthesize the molecularly imprinted microspheres (MIMs) for the topical anesthetic benzocaine (BZC). The desired diameter (10-20 μm) and uniform morphology of the MIMs were obtained easily by changing one or more of the synthesis conditions, including type and amount of surfactant, stirring rate, and ratio of organic to water phase. The MIMs obtained were used as a molecular-imprinting solid-phase-extraction (MISPE) material for extraction of BZC in human serum and fish tissues. The MISPE results revealed that the BZC in these biosamples could be enriched effectively after the MISPE operation. The recoveries of BZC on MIMs cartridges were higher than 90% (n = 3). Finally, an MISPE-HPLC method with UV detection was developed for highly selective extraction and fast detection of trace BZC in human serum and fish tissues. The developed method could also be used for the enrichment and detection of BZC in other complex biosamples.

Pharmacokinetics and Tissue Distribution Study of Chlorogenic Acid from Lonicerae Japonicae Flos Following Oral Administrations in Rats

PubMed Central

Zhou, Yulu; Zhou, Ting; Pei, Qi; Liu, Shikun; Yuan, Hong

2014-01-01

Chlorogenic acid (ChA) is proposed as the major bioactive compounds of Lonicerae Japonicae Flos (LJF). Forty-two Wistar rats were randomly divided into seven groups to investigate the pharmacokinetics and tissue distribution of ChA, via oral administration of LJF extract, using ibuprofen as internal standard, employing a high performance liquid chromatography in conjunction with tandem mass spectrometry. Analytes were extracted from plasma samples and tissue homogenate by liquid–liquid extraction with acetonitrile, separated on a C 18 column by linear gradient elution, and detected by electrospray ionization mass spectrometry in negative selected multiple reaction monitoring mode. Our results successfully demonstrate that the method has satisfactory selectivity, linearity, extraction recovery, matrix effect, precision, accuracy, and stability. Using noncompartment model to study pharmacokinetics, profile revealed that ChA was rapidly absorbed and eliminated. Tissue study indicated that the highest level was observed in liver, followed by kidney, lung, heart, and spleen. In conclusion, this method was suitable for the study on pharmacokinetics and tissue distribution of ChA after oral administration. PMID:25140190

Development of Novel Sorbents for Uranium Extraction from Seawater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Wenbin; Taylor-Pashow, Kathryn

2014-01-08

As the uranium resource in terrestrial ores is limited, it is difficult to ensure a long-term sustainable nuclear energy technology. The oceans contain approximately 4.5 billion tons of uranium, which is one thousand times the amount of uranium in terrestrial ores. Development of technologies to recover the uranium from seawater would greatly improve the uranium resource availability, sustaining the fuel supply for nuclear energy. Several methods have been previously evaluated including solvent extraction, ion exchange, flotation, biomass collection, and adsorption; however, none have been found to be suitable for reasons such as cost effectiveness, long term stability, and selectivity. Recentmore » research has focused on the amidoxime functional group as a promising candidate for uranium sorption. Polymer beads and fibers have been functionalized with amidoxime functional groups, and uranium adsorption capacities as high as 1.5 g U/kg adsorbent have recently been reported with these types of materials. As uranium concentration in seawater is only ~3 ppb, great improvements to uranium collection systems must be made in order to make uranium extraction from seawater economically feasible. This proposed research intends to develop transformative technologies for economic uranium extraction from seawater. The Lin group will design advanced porous supports by taking advantage of recent breakthroughs in nanoscience and nanotechnology and incorporate high densities of well-designed chelators into such nanoporous supports to allow selective and efficient binding of uranyl ions from seawater. Several classes of nanoporous materials, including mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), meta-organic frameworks (MOFs), and covalent-organic frameworks (COFs), will be synthesized. Selective uranium-binding liagnds such as amidoxime will be incorporated into the nanoporous materials to afford a new generation of sorbent materials that will be evaluated for their uranium extraction efficiency. The initial testing of these materials for uranium binding will be carried out in the Lin group, but more detailed sorption studies will be carried out by Dr. Taylor-Pashow of Savannah River National Laboratory in order to obtain quantitative uranyl sorption selectivity and kinetics data for the proposed materials. The proposed nanostructured sorbent materials are expected to have higher binding capacities, enhanced extraction kinetics, optimal stripping efficiency for uranyl ions, and enhanced mechanical and chemical stabilities. This transformative research will significantly impact uranium extraction from seawater as well as benefit DOE’s efforts on environmental remediation by developing new materials and providing knowledge for enriching and sequestering ultralow concentrations of other metals.« less

Allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala on three selected weed species

NASA Astrophysics Data System (ADS)

Ishak, Muhamad Safwan; Sahid, Ismail

2014-09-01

A laboratory experiment was conducted to study the allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala. The aqueous extracts were individually tested on three selected weed species, namely goatweed (Ageratum conyzoides), coat buttons (Tridax procumbens) and lilac tasselflower (Emilia sonchifolia). The allelopathic effects of the leaf and seed extracts on germination, shoot length, root length and fresh weight of each of the selected weed species were determined. Germination of goatweed, coat buttons and lilac tasselflower were inhibited by the aqueous extracts of both the leaf and seed of L. leucocephala and was concentration dependent. Different concentrations of the aqueous extracts showed various germination patterns on the selected weeds species. Seedling length and fresh weight of goatweed, coat buttons and lilac tasselflower were reduced in response to respective increasing concentrations of the seed extracts. Maximum inhibition by the aqueous seed extract was observed more on the root rather than the shoot growth. The aqueous seed extract at T3 concentration reduced root length of goatweed, coat buttons and lilac tasselflower by 95%, 86% and 91% (of the control) respectively. The aqueous seed extract showed greater inhibitory effects than that of the aqueous leaf extract.

ON-SITE SOLID-PHASE EXTRACTION AND LABORATORY ...

EPA Pesticide Factsheets

Fragrance materials such as synthetic musks in aqueous samples, are normally determined by gas chromatography/mass spectrometry in the selected ion monitoring (SIM) mode to provide maximum sensitivity after liquid-liquid extraction of I -L samples. Full-scan mass spectra are required to verify that a target analyte has been found by comparison with the mass spectra of fragrance compounds in the NIST mass spectral library. A I -L sample usually provides insufficient analyte for full scan data acquisition. This paper describes an on-site extraction method developed at the U.S. Environmental Protection Agency (USEPA)- Las Vegas Nevada - for synthetic musks from 60 L of wastewater effluent. Such a large sample volume permits high-quality, full-scan mass spectra to be obtained for a wide array of synthetic musks. Quantification of these compounds was achieved from the full-scan data directly, without the need to acquire SIM data. The detection limits obtained with this method are an order of magnitude lower than those obtained from liquid-liquid and other solid phase extraction methods. This method is highly reproducible, and recoveries ranged from 80 to 97% in spiked sewage treatment plant effluent. The high rate of sorbent-sample mass transfer eliminated the need for a methanolic activation step, which reduced extraction time, labor, and solvent use, More samples could be extracted in the field at lower cost. After swnple extraction, the light- weight cartridges ar

Selectivity mapping of the binding sites of (E)-resveratrol imprinted polymers using structurally diverse polyphenolic compounds present in Pinot noir grape skins.

PubMed

Hashim, Shima N N S; Schwarz, Lachlan J; Danylec, Basil; Potdar, Mahesh K; Boysen, Reinhard I; Hearn, Milton T W

2016-12-01

This investigation describes a general procedure for the selectivity mapping of molecularly imprinted polymers, using (E)-resveratrol-imprinted polymers as the exemplar, and polyphenolic compounds present in Pinot noir grape skin extracts as the test compounds. The procedure is based on the analysis of samples generated before and after solid-phase extraction of (E)-resveratrol and other polyphenols contained within the Pinot noir grape skins using (E)-resveratrol-imprinted polymers. Capillary reversed-phase high-performance liquid chromatography (RP-HPLC) and electrospray ionisation tandem mass spectrometry (ESI MS/MS) was then employed for compound analysis and identification. Under optimised solid-phase extraction conditions, the (E)-resveratrol-imprinted polymer showed high binding affinity and selectivity towards (E)-resveratrol, whilst no resveratrol was bound by the corresponding non-imprinted polymer. In addition, quercetin-3-O-glucuronide and a dimer of catechin-methyl-5-furfuraldehyde, which share some structural features with (E)-resveratrol, were also bound by the (E)-resveratrol-imprinted polymer. Polyphenols that were non-specifically retained by both the imprinted and non-imprinted polymer were (+)-catechin, a B-type procyanidin and (-)-epicatechin. The compounds that did not bind to the (E)-resveratrol molecularly imprinted polymer had at least one of the following molecular characteristics in comparison to the (E)-resveratrol template: (i) different spatial arrangements of their phenolic hydroxyl groups, (ii) less than three or more than four phenolic hydroxyl groups, or (iii) contained a bulky substituent moiety. The results show that capillary RP-HPLC in conjunction with ESI MS/MS represent very useful techniques for mapping the selectivity of the binding sites of imprinted polymer. Moreover, this procedure permits performance monitoring of the characteristics of molecularly imprinted polymers intended for solid-phase extraction of bioactive and nutraceutical molecules from diverse agricultural waste sources. Copyright © 2016 Elsevier B.V. All rights reserved.

Determination of N-vinyl-2-pyrrolidone and N-methyl-2-pyrrolidone in drugs using polypyrrole-based headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection.

PubMed

Mehdinia, Ali; Ghassempour, Alireza; Rafati, Hasan; Heydari, Rouhollah

2007-03-21

A headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection (HS-SPME-GC-NPD) method using polypyrrole (PPy) fibers has been introduced to determine two derivatives of pyrrolidone; N-vinyl-2-pyrrolidone (NVP) and N-methyl-2-pyrrolidone (NMP). Two types of PPy fibers, prepared using organic and aqueous media, were compared in terms of extraction efficiency and thermal stability. It was found that PPy film prepared using organic medium (i.e. acetonitrile) had higher extraction efficiency and more thermal stability compared to the film prepared in aqueous medium. To enhance the sensitivity of HS-SPME, the effects of pH, ionic strength, extraction time, extraction temperature and the headspace volume on the extraction efficiency were optimized. Using the results of this research, high sensitivity and selectivity had been achieved due to the combination of the high extraction efficiency of PPy film prepared in organic medium and the high sensitivity and selectivity of nitrogen-phosphorous detection. Linear range of the analytes was found to be between 1.0 and 1000 microg L(-1) with regression coefficients (R(2)) of 0.998 and 0.997 for NVP and NMP, consequently. Limits of detection (LODs) were 0.074 and 0.081 microg L(-1) for NVP and NMP, respectively. Relative standard deviation (R.S.D.) for five replications of analyses was found to be less than 6.0%. In real samples the mean recoveries were 94.81% and 94.15% for NVP and NMP, respectively. The results demonstrated the suitability of the HS-SPME technique for analyzing NVP and NMP in two different pharmaceutical matrices. In addition, the method was used for simultaneous detection of NVP, 2-pyrrolidone (2-Pyr), gamma-butyrolactone (GBL) and ethanolamine (EA) compounds.

Effective traffic features selection algorithm for cyber-attacks samples

NASA Astrophysics Data System (ADS)

Li, Yihong; Liu, Fangzheng; Du, Zhenyu

2018-05-01

By studying the defense scheme of Network attacks, this paper propose an effective traffic features selection algorithm based on k-means++ clustering to deal with the problem of high dimensionality of traffic features which extracted from cyber-attacks samples. Firstly, this algorithm divide the original feature set into attack traffic feature set and background traffic feature set by the clustering. Then, we calculates the variation of clustering performance after removing a certain feature. Finally, evaluating the degree of distinctiveness of the feature vector according to the result. Among them, the effective feature vector is whose degree of distinctiveness exceeds the set threshold. The purpose of this paper is to select out the effective features from the extracted original feature set. In this way, it can reduce the dimensionality of the features so as to reduce the space-time overhead of subsequent detection. The experimental results show that the proposed algorithm is feasible and it has some advantages over other selection algorithms.

Evaluation of entropy and JM-distance criterions as features selection methods using spectral and spatial features derived from LANDSAT images

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator); Dutra, L. V.; Mascarenhas, N. D. A.; Mitsuo, Fernando Augusta, II

1984-01-01

A study area near Ribeirao Preto in Sao Paulo state was selected, with predominance in sugar cane. Eight features were extracted from the 4 original bands of LANDSAT image, using low-pass and high-pass filtering to obtain spatial features. There were 5 training sites in order to acquire the necessary parameters. Two groups of four channels were selected from 12 channels using JM-distance and entropy criterions. The number of selected channels was defined by physical restrictions of the image analyzer and computacional costs. The evaluation was performed by extracting the confusion matrix for training and tests areas, with a maximum likelihood classifier, and by defining performance indexes based on those matrixes for each group of channels. Results show that in spatial features and supervised classification, the entropy criterion is better in the sense that allows a more accurate and generalized definition of class signature. On the other hand, JM-distance criterion strongly reduces the misclassification within training areas.

Reinforcement of the bio-gas conversion from pyrolysis of wheat straw by hot caustic pre-extraction.

PubMed

Zhang, Lilong; Chen, Keli; He, Liang; Peng, Lincai

2018-01-01

Pyrolysis has attracted growing interest as a versatile means to convert biomass into valuable products. Wheat straw has been considered to be a promising biomass resource due to its low price and easy availability. However, most of the products obtained from wheat straw pyrolysis are usually of low quality. Hot soda extraction has the advantage of selective dissolution of lignin whilst retaining the carbohydrates. This can selectively convert biomass into high-quality desired products and suppress the formation of undesirable products. The aim of this study was to investigate the pyrolysis properties of wheat straw under different hot caustic pretreatment conditions. Compared with the untreated straw, a greater amount of gas was released and fewer residues were retained in the extracted wheat straw, which was caused by an increase in porosity. When the NaOH loading was 14%, the average pore size of the extracted straw increased by 12% and the cumulative pore volume increased by 157% compared with the untreated straw. The extracted straw obtained from the 14% NaOH extraction was clearly selective for pyrolysis products. On one hand, many lignin pyrolysis products disappeared, and only four main lignin-unit-pyrolysis products were retained. On the other hand, polysaccharide pyrolysis products were enriched. Both propanone and furfural have outstanding peak intensities that could account for approximately 30% of the total pyrolysis products. However, with the excessive addition of NaOH (i.e. > 22% w/w) during pretreatment, the conversion of bio-gas products decreased. Thermogravimetric and low-temperature nitrogen-adsorption analysis showed that the pore structure had been seriously destroyed, leading to the closing of the release paths of the bio-gas and thus increasing the re-polymerisation of small bio-gas molecules. After suitable extraction (14% NaOH loading extraction), a considerable amount (25%) of the soluble components dissolved out of the straw. This resulted in an increase in both pore size and volume. This condition appeared to be optimally selective for the release of value-added pyrolysis products such as furfural, ketones and lignin monomer units. However, excessive addition of alkali (22%) for extraction could change the original interior structure, resulting in a decrease in both pore size and volume. This interior structure modification limited the release of pyrolysis products, and greater carbonisation occurred.

Extraction of SelectSecure leads compared to conventional pacing leads in patients with congenital heart disease and congenital atrioventricular block.

PubMed

Shepherd, Emma; Stuart, Graham; Martin, Rob; Walsh, Mark A

2015-06-01

SelectSecure™ pacing leads (Medtronic Inc) are increasingly being used in pediatric patients and adults with structural congenital heart disease. The 4Fr lead is ideal for patients who may require lifelong pacing and can be advantageous for patients with complex anatomy. The purpose of this study was to compare the extraction of SelectSecure leads with conventional (stylette-driven) pacing leads in patients with structural congenital heart disease and congenital atrioventricular block. The data on lead extractions from pediatric and adult congenital heart disease (ACHD) patients from August 2004 to July 2014 at Bristol Royal Hospital for Children and the Bristol Heart Institute were reviewed. Multivariable regression analysis was used to determine whether conventional pacing leads were associated with a more difficult extraction process. A total of 57 patients underwent pacemaker lead extractions (22 SelectSecure, 35 conventional). No deaths occurred. Mean age at the time of extraction was 17.6 ± 10.5 years, mean weight was 47 ± 18 kg, and mean lead age was 5.6 ± 2.6 years (range 1-11 years). Complex extraction (partial extraction/femoral extraction) was more common in patients with conventional pacing leads at univariate (P < .01) and multivariate (P = .04) levels. Lead age was also a significant predictor of complex extraction (P < .01). SelectSecure leads can be successfully extracted using techniques that are used for conventional pacing leads. They are less likely to be partially extracted and are less likely to require extraction using a femoral approach compared with conventional pacing leads. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

19.2% Efficient InP Heterojunction Solar Cell with Electron-Selective TiO2 Contact

PubMed Central

2015-01-01

We demonstrate an InP heterojunction solar cell employing an ultrathin layer (∼10 nm) of amorphous TiO2 deposited at 120 °C by atomic layer deposition as the transparent electron-selective contact. The TiO2 film selectively extracts minority electrons from the conduction band of p-type InP while blocking the majority holes due to the large valence band offset, enabling a high maximum open-circuit voltage of 785 mV. A hydrogen plasma treatment of the InP surface drastically improves the long-wavelength response of the device, resulting in a high short-circuit current density of 30.5 mA/cm2 and a high power conversion efficiency of 19.2%. PMID:25679010

Selective removal of natural caries lesions from dentin and tooth occlusal surfaces using a diode-pumped Er:YAG laser

NASA Astrophysics Data System (ADS)

Jew, Jamison; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

2017-02-01

Selective removal of caries lesions with high precision is best accomplished using lasers operating at high pulse repetition rates utilizing small spot sizes. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped solid-state (DPSS) Er:YAG lasers have become available operating at high pulse repetition rates. Microradiography was used to determine the mineral content of the demineralized dentin of 200-μm thick sections with natural caries lesions prior to laser ablation. The purpose of this study was to explore the use of a DPSS Er:YAG laser for the selective removal of demineralized dentin and natural occlusal lesions on extracted teeth.

19.2% Efficient InP Heterojunction Solar Cell with Electron-Selective TiO2 Contact.

PubMed

Yin, Xingtian; Battaglia, Corsin; Lin, Yongjing; Chen, Kevin; Hettick, Mark; Zheng, Maxwell; Chen, Cheng-Ying; Kiriya, Daisuke; Javey, Ali

2014-12-17

We demonstrate an InP heterojunction solar cell employing an ultrathin layer (∼10 nm) of amorphous TiO 2 deposited at 120 °C by atomic layer deposition as the transparent electron-selective contact. The TiO 2 film selectively extracts minority electrons from the conduction band of p-type InP while blocking the majority holes due to the large valence band offset, enabling a high maximum open-circuit voltage of 785 mV. A hydrogen plasma treatment of the InP surface drastically improves the long-wavelength response of the device, resulting in a high short-circuit current density of 30.5 mA/cm 2 and a high power conversion efficiency of 19.2%.

Enhanced and green extraction polyphenols and furanocoumarins from Fig (Ficus carica L.) leaves using deep eutectic solvents.

PubMed

Wang, Tong; Jiao, Jiao; Gai, Qing-Yan; Wang, Peng; Guo, Na; Niu, Li-Li; Fu, Yu-Jie

2017-10-25

Nowadays, green extraction of bioactive compounds from medicinal plants has gained increasing attention. As green solvent, deep eutectic solvent (DES) have been highly rated to replace toxic organic solvents in extraction process. In present study, to simultaneous extraction five main bioactive compounds from fig leaves, DES was tailor-made. The tailor-made DES composed of a 3:3:3 molar ratio of glycerol, xylitol and D-(-)-Fructose showed enhanced extraction yields for five target compounds simultaneously compared with traditional methanol and non-tailor DESs. Then, the tailor-made DES based extraction methods have compared and microwave-assisted extraction was selected and optimized due to its high extraction yields with lower time consumption. The influencing parameters including extraction temperature, liquid-solid ratio, and extraction time were optimized using response surface methodology (RSM). Under optimal conditions the extraction yield of caffeoylmalic acid, psoralic acid-glucoside, rutin, psoralen and bergapten was 6.482mg/g, 16.34mg/g, 5.207mg/g, 15.22mg/g and 2.475mg/g, respectively. Macroporous resin D101 has been used to recovery target compounds with recovery yields of 79.2%, 83.4%, 85.5%, 81.2% and 75.3% for caffeoylmalic acid, psoralic acid-glucoside, rutin, psoralen and bergapten, respectively. The present study suggests that DESs are truly designer and efficient solvents and the method we developed was efficient and sustainable for extraction main compounds from Fig leaves.mg/g. Copyright © 2017 Elsevier B.V. All rights reserved.

Feature Extraction and Selection Strategies for Automated Target Recognition

NASA Technical Reports Server (NTRS)

Greene, W. Nicholas; Zhang, Yuhan; Lu, Thomas T.; Chao, Tien-Hsin

2010-01-01

Several feature extraction and selection methods for an existing automatic target recognition (ATR) system using JPLs Grayscale Optical Correlator (GOC) and Optimal Trade-Off Maximum Average Correlation Height (OT-MACH) filter were tested using MATLAB. The ATR system is composed of three stages: a cursory region of-interest (ROI) search using the GOC and OT-MACH filter, a feature extraction and selection stage, and a final classification stage. Feature extraction and selection concerns transforming potential target data into more useful forms as well as selecting important subsets of that data which may aide in detection and classification. The strategies tested were built around two popular extraction methods: Principal Component Analysis (PCA) and Independent Component Analysis (ICA). Performance was measured based on the classification accuracy and free-response receiver operating characteristic (FROC) output of a support vector machine(SVM) and a neural net (NN) classifier.

Feature extraction and selection strategies for automated target recognition

NASA Astrophysics Data System (ADS)

Greene, W. Nicholas; Zhang, Yuhan; Lu, Thomas T.; Chao, Tien-Hsin

2010-04-01

Several feature extraction and selection methods for an existing automatic target recognition (ATR) system using JPLs Grayscale Optical Correlator (GOC) and Optimal Trade-Off Maximum Average Correlation Height (OT-MACH) filter were tested using MATLAB. The ATR system is composed of three stages: a cursory regionof- interest (ROI) search using the GOC and OT-MACH filter, a feature extraction and selection stage, and a final classification stage. Feature extraction and selection concerns transforming potential target data into more useful forms as well as selecting important subsets of that data which may aide in detection and classification. The strategies tested were built around two popular extraction methods: Principal Component Analysis (PCA) and Independent Component Analysis (ICA). Performance was measured based on the classification accuracy and free-response receiver operating characteristic (FROC) output of a support vector machine(SVM) and a neural net (NN) classifier.

Platform construction and extraction mechanism study of magnetic mixed hemimicelles solid-phase extraction

NASA Astrophysics Data System (ADS)

Xiao, Deli; Zhang, Chan; He, Jia; Zeng, Rong; Chen, Rong; He, Hua

2016-12-01

Simple, accurate and high-throughput pretreatment method would facilitate large-scale studies of trace analysis in complex samples. Magnetic mixed hemimicelles solid-phase extraction has the power to become a key pretreatment method in biological, environmental and clinical research. However, lacking of experimental predictability and unsharpness of extraction mechanism limit the development of this promising method. Herein, this work tries to establish theoretical-based experimental designs for extraction of trace analytes from complex samples using magnetic mixed hemimicelles solid-phase extraction. We selected three categories and six sub-types of compounds for systematic comparative study of extraction mechanism, and comprehensively illustrated the roles of different force (hydrophobic interaction, π-π stacking interactions, hydrogen-bonding interaction, electrostatic interaction) for the first time. What’s more, the application guidelines for supporting materials, surfactants and sample matrix were also summarized. The extraction mechanism and platform established in the study render its future promising for foreseeable and efficient pretreatment under theoretical based experimental design for trace analytes from environmental, biological and clinical samples.

High-Throughput Screening of Australian Marine Organism Extracts for Bioactive Molecules Affecting the Cellular Storage of Neutral Lipids

PubMed Central

Rae, James; Fontaine, Frank; Salim, Angela A.; Lo, Harriet P.; Capon, Robert J.; Parton, Robert G.; Martin, Sally

2011-01-01

Mammalian cells store excess fatty acids as neutral lipids in specialised organelles called lipid droplets (LDs). Using a simple cell-based assay and open-source software we established a high throughput screen for LD formation in A431 cells in order to identify small bioactive molecules affecting lipid storage. Screening an n-butanol extract library from Australian marine organisms we identified 114 extracts that produced either an increase or a decrease in LD formation in fatty acid-treated A431 cells with varying degrees of cytotoxicity. We selected for further analysis a non-cytotoxic extract derived from the genus Spongia (Heterofibria). Solvent partitioning, HPLC fractionation and spectroscopic analysis (NMR, MS) identified a family of related molecules within this extract with unique structural features, a subset of which reduced LD formation. We selected one of these molecules, heterofibrin A1, for more detailed cellular analysis. Inhibition of LD biogenesis by heterofibrin A1 was observed in both A431 cells and AML12 hepatocytes. The activity of heterofibrin A1 was dose dependent with 20 µM inhibiting LD formation and triglyceride accumulation by ∼50% in the presence of 50 µM oleic acid. Using a fluorescent fatty acid analogue we found that heterofibrin A1 significantly reduces the intracellular accumulation of fatty acids and results in the formation of distinct fatty acid metabolites in both cultured cells and in embryos of the zebrafish Danio rerio. In summary we have shown using readily accessible software and a relatively simple assay system that we can identify and isolate bioactive molecules from marine extracts, which affect the formation of LDs and the metabolism of fatty acids both in vitro and in vivo. PMID:21857959

High-performance thin-layer chromatography linked with (bio)assays and mass spectrometry - a suited method for discovery and quantification of bioactive components? Exemplarily shown for turmeric and milk thistle extracts.

PubMed

Taha, Mahmoud N; Krawinkel, Michael B; Morlock, Gertrud E

2015-05-15

Extraction parameters, chemical fingerprint, and the single compounds' activity levels were considered for the selection of active botanicals. For an initial survey, the total bioactivity (i.e., total reducing capacity, total flavonoids contents and free radical scavenging capacity) of 21 aqueous and 21 ethanolic plant extracts was investigated. Ethanolic extracts showed a higher yield and were further analyzed by HPTLC in detail to obtain fingerprints of single flavonoids and further bioactive components. Exemplarily shown for turmeric (Curcuma longa) and milk thistle (Silybum marianum), effect-directed analysis (EDA) was performed using three selected (bio)assays, the Aliivibrio fischeri bioassay, the Bacillus subtilis bioassay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH*) assay. As a proof of principle, the bioactive components found in the extracts were confirmed by HPTLC-MS. Bioassays in combination with planar chromatography directly linked to the known, single effective compounds like curcumin and silibinin. However, also some unknown bioactive components were discovered and exemplarily characterized, which demonstrated the strength of this kind of EDA. HPTLC-UV/Vis/FLD-EDA-MS could become a useful tool for selection of active botanicals and for the activity profiling of the active ingredients therein. The flexibility in effect-directed detections allows a comprehensive survey of effective ingredients in samples. This streamlined methodology comprised a non-targeted, effect-directed screening first, followed by a highly targeted characterization of the discovered bioactive compounds. HPTLC-EDA-MS can also be recommended for bioactivity profiling of food on the food intake side, as not only effective phytochemicals, but also unknown bioactive degradation products during food processing or contamination products or residues or metabolites can be detected. Thus, an efficient survey on potential food intake effects on wellness could be obtained. Having performed both, sum parameter assays and HPTLC analysis, a comparison of both approaches was made and discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

An efficient approach to selective electromembrane extraction of naproxen by means of molecularly imprinted polymer-coated multi-walled carbon nanotubes-reinforced hollow fibers.

PubMed

Tahmasebi, Zeinab; Davarani, Saied Saeed Hosseiny; Asgharinezhad, Ali Akbar

2016-10-28

In this work, a novel microextraction technique using molecularly imprinted polymer-coated multi-walled carbon nanotubes (MIP-MWCNTs) in electromembrane extraction (EME) procedure is described. The method in combination with HPLC-UV was utilized to determine naproxen, as an acidic model drug, in urine, plasma and wastewater samples. For this purpose, MIP-MWCNTs were placed in the pores of polypropylene hollow fiber. The MIP-MWCNTs-EME method has the advantages of high selectivity and cleanup of MIP along with high enrichment ability of the EME in a single step extraction. Continuing with the research, optimization of the factors affecting the migration of naproxen from sample solutions to MIP-MWCNTs sites and then into the lumen of hollow fiber was explored. Under the optimized conditions, the limit of detection (LOD) of the developed method was calculated to be 0.3μgL -1 . All relative standard deviations (RSDs) were lower than 3%. Linearity of the method was obtained within the range of 1-1000μgL -1 with the coefficient of determination (r 2 ) being higher than 0.999. Under the optimized conditions, an extraction recovery of 66% was obtained, which corresponded to a preconcentration factor of 88. Finally, the developed method was satisfactorily used to determine naproxen in urine, plasma and wastewater samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Capillary electrophoresis coupled with chloroform-acetonitrile extraction for rapid and highly selective determination of cysteine and homocysteine levels in human blood plasma and urine.

PubMed

Ivanov, Alexander Vladimirovich; Bulgakova, Polina Olegovna; Virus, Edward Danielevich; Kruglova, Maria Petrovna; Alexandrin, Valery Vasil'evich; Gadieva, Viktoriya Aleksandrovna; Luzyanin, Boris Petrovich; Kushlinskii, Nikolai Evgen'evich; Fedoseev, Anatolij Nikolaevich; Kubatiev, Aslan Amirkhanovich

2017-10-01

A rapid and selective method has been developed for highly sensitive determination of total cysteine and homocysteine levels in human blood plasma and urine by capillary electrophoresis (CE) coupled with liquid-liquid extraction. Analytes were first derivatized with 1,1'-thiocarbonyldiimidazole and then samples were purified by chloroform-ACN extraction. Electrophoretic separation was performed using 0.1 M phosphate with 30 mM triethanolamine, pH 2, containing 25 μM CTAB, 2.5 μM SDS, and 2.5% polyethylene glycol 600. Samples were injected into the capillary (with total length 32 cm and 50 μm id) at 2250 mbar*s and subsequent injection was performed for 30 s with 0.5 M KОН. The total analysis time was less than 9 min, accuracy was 98%, and precision was <2.6%. The LOD was 0.2 μM for homocysteine and 0.5 μM for cysteine. The use of liquid-liquid extraction allowed the precision and sensitivity of the CE method to be significantly increased. The validated method was applied to determine total cysteine and homocysteine content in human blood plasma and urine samples obtained from healthy volunteers and patients with kidney disorders. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Xiangping; Chen, Yongbin; Zhou, Tao, E-mail: zhoutao@csu.edu.cn

2015-04-15

Highlights: • Selective precipitation and solvent extraction were adopted. • Nickel, cobalt and lithium were selectively precipitated. • Co-D2EHPA was employed as high-efficiency extraction reagent for manganese. • High recovery percentages could be achieved for all metal values. - Abstract: Environmentally hazardous substances contained in spent Li-ion batteries, such as heavy metals and nocuous organics, will pose a threat to the environment and human health. On the other hand, the sustainable recycling of spent lithium-ion batteries may bring about environmental and economic benefits. In this study, a hydrometallurgical process was adopted for the comprehensive recovery of nickel, manganese, cobalt andmore » lithium from sulfuric acid leaching liquor from waste cathode materials of spent lithium-ion batteries. First, nickel ions were selectively precipitated and recovered using dimethylglyoxime reagent. Recycled dimethylglyoxime could be re-used as precipitant for nickel and revealed similar precipitation performance compared with fresh dimethylglyoxime. Then the separation of manganese and cobalt was conducted by solvent extraction method using cobalt loaded D2EHPA. And McCabe–Thiele isotherm was employed for the prediction of the degree of separation and the number of extraction stages needed at specific experimental conditions. Finally, cobalt and lithium were sequentially precipitated and recovered as CoC{sub 2}O{sub 4}⋅2H{sub 2}O and Li{sub 2}CO{sub 3} using ammonium oxalate solution and saturated sodium carbonate solution, respectively. Recovery efficiencies could be attained as follows: 98.7% for Ni; 97.1% for Mn, 98.2% for Co and 81.0% for Li under optimized experimental conditions. This hydrometallurgical process may promise a candidate for the effective separation and recovery of metal values from the sulfuric acid leaching liquor.« less

Environmental geochemistry of a highly polluted area: the Mazarambroz Pb-Zn mine (Castilla-La Mancha region, Spain)

NASA Astrophysics Data System (ADS)

González-Corrochano, Beatriz; Higueras, Pablo; Jurado, Verónica; María Esbrí, José; Martínez-Coronado, Alba; Alonso-Azcárate, Jacinto

2013-04-01

Human activities, as mining, can alter the concentrations of metals in the environmental compartments and facilitate their dispersion (Moreno Grau, 2003). Total concentrations are usually evaluated, but they do not provide information about the bioavailability and toxicity of metals, since changes in the environmental conditions cause selective release of the total metal content (Sahuquillo et al., 2003). Thus, the bioavailability or toxic effects of the metals can only be studied by determining their chemical partitioning (Quevauviller, 1998). Leaching by selective chemical extracts is the conventional method for evaluating the availability of elements. The Mazarambroz Pb-Zn mine, located in the Castilla-La Mancha region (central Spain), is an important case of abandoned Pb-Zn sulphide mine, with high concentrations of other highly toxic heavy metals such as Cu, As and Cd. The objectives of this work were to determine the extent of the heavy metal contamination and to study the heavy metal bioavailability, by the application of selective chemical extractions, in the Mazarambroz mine area. Soil and sediment samples were taken from the studied area according to a systematic sampling type (regular grid). Soil main parameters (reactivity and conductivity) were determined. Chemical extractions were made using two different selective reagents: i) CaCl2 (0.01M) (Novozamsky et al., 1993) and; ii) EDTA (0.05 M) (Quevauviller, 1996). The contents of heavy metals in the extracts were measured by inductively coupled plasma-mass spectroscopy (ICP-MS). The compounds extracted with the CaCl2 solution represent the water soluble and exchangeable fractions, so they can be considered as the metal concentration that can be absorbed by plants. EDTA solution extracts metals on exchange sites of both inorganic and organic complexes. Additionally, it can dissolve calcareous materials through complexation of calcium and magnesium (Chao, 1984; Sahuquillo et al., 2003). Total geochemical analyses of the samples were carried out using a Field Portable X-Ray Fluorescence Spectroscopy analyser (EDXRF). Results were statistically processed with Minitab 15.0 and mapped with Surfer 9. The mean concentrations of the studied heavy metals are significantly higher than the world average, the Castilla-La Mancha region mean and the local reference value for soils, so the studied area can be considered a polluted area as consequence of the mining process carried out in the Mazarambroz Pb-Zn mine. The total affected area by high concentrations of heavy metals differs depending on the studied element, reaching the maximum extension and importance for lead and zinc. In the studied area, soil and sediments are also affected by very low pH and high conductivity, which indicates the presence of soluble salts, likely sulfates, products of the sulfide oxidation. These results would imply an increase in the heavy metal mobility and transference to the plants and, as a consequence, an increase in the environmental damage since the area close to the mine is used for the cultivation of cereals and rabbit hutting. The results of the extractions show that the highest extracted concentrations are obtained from the sediment samples due to the influence of the stream in the weathering of this type of materials. References - Chao, T.T., 1984. Use of partial dissolution techniques in geochemical exploration. Journal of Geochemical Exploration, 20, 101-135. - Moreno Grau, M.D., 2003. Environmental Toxicology: Risk Assessment to Human Health. Mc Graw Hill, Madrid. - Novozamsky, I., Lexmond, T.M., Houba, V.J.G., 1993. A single extraction procedure of soil for evaluation of uptake f some heavy metals by plants. International Journal of Environmental Analytical Chemistry, 51, 47-58. - Quevauviller, P., Lachica, M., Barahona, E., Rauret, G., Ure, A., Gomez, A., Muntau, H., 1996. Interlaboratory comparison of EDTA and DTPA procedures prior to certification of extractable trace elements in calcareous soil. Science of the Total Environment, 178, 137-132. - Quevauviller, Ph., 1998. Operationally defined extraction procedures for soil and sediment analysis I. Standardization. Trac-Trends in Analytical Chemistry, 17 (5), 289-298. - Sahuquillo, A., Rigol, A., Rauret, G., 2003. Overview of the use of leaching/extraction tests for risk assessment of trace metals in contaminated soils and sediments. Trac-Trends in Analytical Chemistry, 22 (3), 152-159.

Preparation of ellagic acid molecularly imprinted polymeric microspheres based on distillation-precipitation polymerization for the efficient purification of a crude extract.

PubMed

Zhang, Hua; Zhao, Shangge; Zhang, Lu; Han, Bo; Yao, Xincheng; Chen, Wen; Hu, Yanli

2016-08-01

Molecularly imprinted polymeric microspheres with a high recognition ability toward the template molecule, ellagic acid, were synthesized based on distillation-precipitation polymerization. The as-obtained polymers were characterized by scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. Static, dynamic, and selective binding tests were adopted to study the binding properties and the molecular recognition ability of the prepared polymers for ellagic acid. The results indicated that the maximum static adsorption capacity of the prepared polymers toward ellagic acid was 37.07 mg/g and the adsorption equilibrium time was about 100 min when the concentration of ellagic acid was 40 mg/mL. Molecularly imprinted polymeric microspheres were also highly selective toward ellagic acid compared with its analogue quercetin. It was found that the content of ellagic acid in the pomegranate peel extract was enhanced from 23 to 86% after such molecularly imprinted solid-phase extraction process. This work provides an efficient way for effective separation and enrichment of ellagic acid from complex matrix, which is especially valuable in industrial production. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Peroxyoxalate chemiluminescence detection for the highly sensitive determination of fluorescence-labeled chlorpheniramine with Suzuki coupling reaction.

PubMed

Adutwum, Lawrence Asamoah; Kishikawa, Naoya; Ohyama, Kaname; Harada, Shiro; Nakashima, Kenichiro; Kuroda, Naotaka

2010-09-01

A sensitive and selective high performance liquid chromatography-peroxyoxalate chemiluminescence (PO-CL) method has been developed for the simultaneous determination of chlorpheniramine (CPA) and monodesmethyl chlorpheniramine (MDCPA) in human serum. The method combines fluorescent labeling with 4-(4,5-diphenyl-1H-imidazole-2-yl)phenyl boronic acid using Suzuki coupling reaction with PO-CL detection. CPA and MDCPA were extracted from human serum by liquid-liquid extraction with n-hexane. Excess labeling reagent, which interfered with trace level determination of analytes, was removed by solid-phase extraction using a C18 cartridge. Separation of derivatives of both analytes was achieved isocratically on a silica column with a mixture of acetonitrile and 60 mM imidazole-HNO(3) buffer (pH 7.2; 85:15, v/v) containing 0.015% triethylamine. The proposed method exhibited a good linearity with a correlation coefficient of 0.999 for CPA and MDCPA within the concentration range of 0.5-100 ng/mL. The limits of detection (S/N = 3) were 0.14 and 0.16 ng/mL for CPA and MDCPA, respectively. Using the proposed method, CPA could be selectively determined in human serum after oral administration.

Aptamer-conjugated nanoparticles for cancer cell detection.

PubMed

Medley, Colin D; Bamrungsap, Suwussa; Tan, Weihong; Smith, Joshua E

2011-02-01

Aptamer-conjugated nanoparticles (ACNPs) have been used for a variety of applications, particularly dual nanoparticles for magnetic extraction and fluorescent labeling. In this type of assay, silica-coated magnetic and fluorophore-doped silica nanoparticles are conjugated to highly selective aptamers to detect and extract targeted cells in a variety of matrixes. However, considerable improvements are required in order to increase the selectivity and sensitivity of this two-particle assay to be useful in a clinical setting. To accomplish this, several parameters were investigated, including nanoparticle size, conjugation chemistry, use of multiple aptamer sequences on the nanoparticles, and use of multiple nanoparticles with different aptamer sequences. After identifying the best-performing elements, the improvements made to this assay's conditional parameters were combined to illustrate the overall enhanced sensitivity and selectivity of the two-particle assay using an innovative multiple aptamer approach, signifying a critical feature in the advancement of this technique.

Fast Extraction and Detection of 4-Methylimidazole in Soy Sauce Using Magnetic Molecularly Imprinted Polymer by HPLC.

PubMed

Feng, Zufei; Lu, Yan; Zhao, Yingjuan; Ye, Helin

2017-11-02

On the basis of magnetic molecularly imprinted polymer (MMIP) solid-phase extraction coupled with high performance liquid chromatography, we established a new method for the determination of the 4-methylimidazole (4-MEI) in soy sauce. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) were used to characterize the synthesized MMIPs. To evaluate the polymers, batch rebinding experiments were carried out. The binding strength and capacity were determined from the derived Freundlich isotherm (FI) equation. The selective recognition capability of MMIPs was investigated with a reference compound and a structurally similar compound. As a selective pre-concentration sorbents for 4-methylimidazole in soy sauce, the MMIPs showed a satisfied recoveries rate of spiked samples, ranged from 97% to 105%. As a result, the prepared MMIPs could be applied to selectively pre-concentrate and determine 4-methylimidazole in soy sauce samples.

Classification of high-resolution multispectral satellite remote sensing images using extended morphological attribute profiles and independent component analysis

NASA Astrophysics Data System (ADS)

Wu, Yu; Zheng, Lijuan; Xie, Donghai; Zhong, Ruofei

2017-07-01

In this study, the extended morphological attribute profiles (EAPs) and independent component analysis (ICA) were combined for feature extraction of high-resolution multispectral satellite remote sensing images and the regularized least squares (RLS) approach with the radial basis function (RBF) kernel was further applied for the classification. Based on the major two independent components, the geometrical features were extracted using the EAPs method. In this study, three morphological attributes were calculated and extracted for each independent component, including area, standard deviation, and moment of inertia. The extracted geometrical features classified results using RLS approach and the commonly used LIB-SVM library of support vector machines method. The Worldview-3 and Chinese GF-2 multispectral images were tested, and the results showed that the features extracted by EAPs and ICA can effectively improve the accuracy of the high-resolution multispectral image classification, 2% larger than EAPs and principal component analysis (PCA) method, and 6% larger than APs and original high-resolution multispectral data. Moreover, it is also suggested that both the GURLS and LIB-SVM libraries are well suited for the multispectral remote sensing image classification. The GURLS library is easy to be used with automatic parameter selection but its computation time may be larger than the LIB-SVM library. This study would be helpful for the classification application of high-resolution multispectral satellite remote sensing images.

Hollow fiber-based liquid-liquid-liquid micro-extraction with osmosis: II. Application to quantification of endogenous gibberellins in rice plant.

PubMed

Wu, Qian; Wu, Dapeng; Duan, Chunfeng; Shen, Zheng; Guan, Yafeng

2012-11-23

The phenomenon and benefits of osmosis in hollow fiber-based liquid-liquid-liquid micro-extraction (HF-LLLME) were theoretically discussed in part I of this study. In this work, HF-LLLME with osmosis was coupled with high performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-triple quadrupole MS/MS) to analyze eight gibberellins (gibberellin A(1), gibberellin A(3), gibberellin A(4), gibberellin A(7), gibberellin A(8), gibberellin A(9), gibberellin A(19) and gibberellin A(20)) in rice plant samples. According to the theory of HF-LLLME with osmosis, single factor experiments, orthogonal design experiments and mass transfer simulation of extraction process were carried out to select the optimal conditions. Cyclohexanol - n-octanol (1:3, v/v) was selected as organic membrane. Donor phase of 12 mL was adjusted to pH 2 and 20% NaCl (w/v) was added. Acceptor phase with an initial volume of 20 μL was the solution of 0.12 mol L(-1) Na(2)CO(3)-NaHCO(3) buffer (pH 9). Temperature was chosen to be 30 °C and extraction time was selected to be 90 min. Under optimized conditions, this method provided good linearity (r, 0.99552-0.99991) and low limits of detection (0.0016-0.061 ng mL(-1)). Finally, this method was applied to the analysis of endogenous gibberellins from plant extract which was obtained with traditional solvent extraction of rice plant tissues, and the relative recoveries were from 62% to 166%. Copyright © 2012 Elsevier B.V. All rights reserved.

Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate-coated nano-magnets for selective adsorption and enrichment of illegal cationic dyes in food matrices prior to high-performance liquid chromatography-diode array detection detection.

PubMed

Qi, Ping; Liang, Zhi-An; Wang, Yu; Xiao, Jian; Liu, Jia; Zhou, Qing-Qiong; Zheng, Chun-Hao; Luo, Li-Ni; Lin, Zi-Hao; Zhu, Fang; Zhang, Xue-Wu

2016-03-11

In this study, mixed hemimicelles solid-phase extraction (MHSPE) based on sodium dodecyl sulfate (SDS) coated nano-magnets Fe3O4 was investigated as a novel method for the extraction and separation of four banned cationic dyes, Auramine O, Rhodamine B, Basic orange 21 and Basic orange 22, in condiments prior to HPLC detection. The main factors affecting the extraction of analysts, such as pH, surfactant and adsorbent concentrations and zeta potential were studied and optimized. Under optimized conditions, the proposed method was successful applied for the analysis of banned cationic dyes in food samples such as chili sauce, soybean paste and tomato sauce. Validation data showed the good recoveries in the range of 70.1-104.5%, with relative standard deviations less than 15%. The method limits of determination/quantification were in the range of 0.2-0.9 and 0.7-3μgkg(-1), respectively. The selective adsorption and enrichment of cationic dyes were achieved by the synergistic effects of hydrophobic interactions and electrostatic attraction between mixed hemimicelles and the cationic dyes, which also resulted in the removal of natural pigments interferences from sample extracts. When applied to real samples, RB was detected in several positive samples (chili powders) within the range from 0.042 to 0.177mgkg(-1). These results indicate that magnetic MHSPE is an efficient and selective sample preparation technique for the extraction of banned cationic dyes in a complex matrix. Copyright © 2016 Elsevier B.V. All rights reserved.

Equilibrium of molybdenum in selected extraction systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tkac, Peter; Paulenova, Alena

2007-07-01

The concentration of molybdenum(VI) in dissolved irradiated nuclear fuel is comparable with the concentrations of Tc, Am and Np. Therefore it is of big interest to understand its behavior under conditions related to the UREX/TRUEX process. The effect of the poly-speciation of molybdenum in aqueous solution on its extraction by neutral solvents TBP and CMPO/TBP was studied. Extraction yields of molybdenum decreased significantly when AHA was added to aqueous phase. Our investigation confirmed a strong ability of the aceto-hydroxamic acid to form complexes with Mo in high acidic solutions. Spectroscopic data (UV-Vis) confirmed that a fraction of the Mo(VI)-AHA complexmore » is present in the organic phase after extraction. (authors)« less

Encapsulation of biological active phenolic compounds extracted from wine wastes in alginate-chitosan microbeads.

PubMed

Moschona, Alexandra; Liakopoulou-Kyriakides, Maria

2018-04-23

Grapes (Vitis vinifera) are produced in large amounts worldwide and mostly are used for winemaking. Their untreated wastes are rich in valuable secondary metabolites, such as phenolics. Thus, in this study, white and red wine wastes (Malagouzia and Syrah variety) were investigated for their added value phenolics, which were analysed by high performance liquid chromatography (HPLC) and electrospray ionisation-mass spectrometry (ESI/MS) and subsequently encapsulated in several polymers. Extracts from all wastes gave high amounts of total phenolics (13 ± 2.72-22 ± 2.69 mg g -1 ) and possessed high antioxidant activity (67-97%). In addition to their significant antibacterial activity against gram-negative and gram-positive bacteria, interesting results were also obtained from their anti-inflammatory and antiplatelet activity, in vitro. Encapsulation of the extracts was selective, leaving out most of sugars and other organic compounds when alginate-chitosan was used. Encapsulation efficiency recorded for all extracts ranged from 55% to 79%. Release studies were also performed in several solutions aiming in their commercial use in food and pharmaceutical industries.

Techno-economic analysis of extraction-based separation systems for acetone, butanol, and ethanol recovery and purification.

PubMed

Grisales Díaz, Víctor Hugo; Olivar Tost, Gerard

2017-01-01

Dual extraction, high-temperature extraction, mixture extraction, and oleyl alcohol extraction have been proposed in the literature for acetone, butanol, and ethanol (ABE) production. However, energy and economic evaluation under similar assumptions of extraction-based separation systems are necessary. Hence, the new process proposed in this work, direct steam distillation (DSD), for regeneration of high-boiling extractants was compared with several extraction-based separation systems. The evaluation was performed under similar assumptions through simulation in Aspen Plus V7.3 ® software. Two end distillation systems (number of non-ideal stages between 70 and 80) were studied. Heat integration and vacuum operation of some units were proposed reducing the energy requirements. Energy requirement of hybrid processes, substrate concentration of 200 g/l, was between 6.4 and 8.3 MJ-fuel/kg-ABE. The minimum energy requirements of extraction-based separation systems, feeding a water concentration in the substrate equivalent to extractant selectivity, and ideal assumptions were between 2.6 and 3.5 MJ-fuel/kg-ABE, respectively. The efficiencies of recovery systems for baseline case and ideal evaluation were 0.53-0.57 and 0.81-0.84, respectively. The main advantages of DSD were the operation of the regeneration column at atmospheric pressure, the utilization of low-pressure steam, and the low energy requirements of preheating. The in situ recovery processes, DSD, and mixture extraction with conventional regeneration were the approaches with the lowest energy requirements and total annualized costs.

Integrating dimension reduction and out-of-sample extension in automated classification of ex vivo human patellar cartilage on phase contrast X-ray computed tomography.

PubMed

Nagarajan, Mahesh B; Coan, Paola; Huber, Markus B; Diemoz, Paul C; Wismüller, Axel

2015-01-01

Phase contrast X-ray computed tomography (PCI-CT) has been demonstrated as a novel imaging technique that can visualize human cartilage with high spatial resolution and soft tissue contrast. Different textural approaches have been previously investigated for characterizing chondrocyte organization on PCI-CT to enable classification of healthy and osteoarthritic cartilage. However, the large size of feature sets extracted in such studies motivates an investigation into algorithmic feature reduction for computing efficient feature representations without compromising their discriminatory power. For this purpose, geometrical feature sets derived from the scaling index method (SIM) were extracted from 1392 volumes of interest (VOI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. The extracted feature sets were subject to linear and non-linear dimension reduction techniques as well as feature selection based on evaluation of mutual information criteria. The reduced feature set was subsequently used in a machine learning task with support vector regression to classify VOIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver-operating characteristic (ROC) curve (AUC). Our results show that the classification performance achieved by 9-D SIM-derived geometric feature sets (AUC: 0.96 ± 0.02) can be maintained with 2-D representations computed from both dimension reduction and feature selection (AUC values as high as 0.97 ± 0.02). Thus, such feature reduction techniques can offer a high degree of compaction to large feature sets extracted from PCI-CT images while maintaining their ability to characterize the underlying chondrocyte patterns.

Extractions of isoquinoline alkaloids with butanol and octanol.

PubMed

Gregorová, Jana; Babica, Jan; Marek, Radek; Paulová, Hana; Táborská, Eva; Dostál, Jirí

2010-09-01

Six different isoquinoline alkaloids (sanguinarine, chelerythrine, berberine, coptisine, allocryptopine, and protopine) were extracted by butanol and octanol from aqueous solution, pH 4.5. The samples were analyzed by HPLC. Butanol extraction was non-selective, alkaloids passed into organic phase in 83-98%. Octanol extraction provided more selective yields: sanguinarine 99%, chelerythrine 94%, berberine 18%, coptisine 16%, allocryptopine 7.5%, protopine 7%. Further, we tested octanol treatment of extract from Dicranostigma lactucoides. The octanol extraction yields were also selective: sanguinarine 98%, chelerythrine 92%, chelirubine 92.5%, protopine 6% and allocryptopine 3.5%. 6-Butoxy-5,6-dihydrosanguinarine and 6-butoxy-5,6-dihydrochelerythrine were prepared and their NMR and MS data are reported and discussed. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Antibacterial Activity of Hawaiian Corals: Possible Protection from Disease?

NASA Astrophysics Data System (ADS)

Gochfeld, D. J.; Aeby, G. S.; Miller, J. D.

2006-12-01

Reports of coral diseases in the Caribbean have appeared with increasing frequency over the past two decades; however, records of coral diseases in the Pacific have lagged far behind. Recent surveys of coral disease in the Hawaiian Islands indicate relatively low, but consistent, levels of disease throughout the inhabited Main and uninhabited Northwestern Hawaiian Islands, and demonstrate variation in levels of disease among the major genera of Hawaiian corals. Although little is known about immune defense to disease in corals, one potential mechanism of defense is the production of antimicrobial compounds that protect corals from pathogens. A preliminary survey of antibacterial chemical defenses among three dominant species of Hawaiian corals was undertaken. Crude aqueous extracts of Porites lobata, Pocillopora meandrina and Montipora capitata were tested against nine strains of bacteria in a growth inhibition assay. Inhibitory extracts were further tested to determine whether their effects were cytostatic or cytotoxic. The bacteria selected included known coral pathogens, potential marine pathogens found in human waste and strains previously identified from the surfaces of Hawaiian corals. Extracts from all three species of coral exhibited a high degree of antibacterial activity, but also a high degree of selectivity against different bacterial strains. In addition, some extracts were stimulatory to some bacteria. In addition to interspecific variability, extracts also exhibited intraspecific variability, both within and between sites. Hawaiian corals have significant antibacterial activity, which may explain the relatively low prevalence of disease in these corals; however, further characterization of pathogens specifically responsible for disease in Hawaiian corals is necessary before we can conclude that antibacterial activity protects Hawaiian corals from disease.

Polydimethylsiloxane rod extraction, a novel technique for the determination of organic micropollutants in water samples by thermal desorption-capillary gas chromatography-mass spectrometry.

PubMed

Montero, L; Popp, P; Paschke, A; Pawliszyn, J

2004-01-30

A novel, simple and inexpensive approach to absorptive extraction of organic compounds from environmental samples is presented. It consists of a polydimethylsiloxane rod used as an extraction media, enriched with analytes during shaking, then thermally desorbed and analyzed by GC-MS. Its performance was illustrated and evaluated for the enrichment of sub- to ng/l of selected chlorinated compounds (chlorobenzenes and polychlorinated biphenyls) in water samples. The new approach was compared to the stir bar sorptive extraction performance. A natural ground water sample from Bitterfeld, Germany, was also extracted using both methods, showing good agreement. The proposed approach presented good linearity, high sensitivity, good blank levels and recoveries comparable to stir bars, together with advantages such as simplicity, lower cost and higher feasibility.

A new molecularly imprinted polymer (MIP)-based electrochemical sensor for monitoring 2,4,6-trinitrotoluene (TNT) in natural waters and soil samples.

PubMed

Alizadeh, Taher; Zare, Mashaalah; Ganjali, Mohamad Reza; Norouzi, Parviz; Tavana, Babak

2010-01-15

A high selective voltammetric sensor for 2,4,6-trinitrotoluene (TNT) was introduced. TNT selective MIP and non-imprinted polymer (NIP) were synthesized and then used for carbon paste (CP) electrode preparation. The MIP, incorporated in the carbon paste electrode, functioned as selectively recognition element and pre-concentrator agent for TNT determination. The prepared electrode was used for TNT measurement by the three steps procedure, including analyte extraction in the electrode, electrode washing and electrochemical measurement of TNT. The MIP-CP electrode showed very high recognition ability in comparison to NIP-CP. It was shown that electrode washing after TNT extraction led to enhanced selectivity. The response of square wave voltammetry for TNT determination by proposed electrode was higher than that of differential pulse voltammetry. Some parameters affecting sensor response were optimized and then a calibration curve plotted. A dynamic linear range of 5x10(-9) to 1x10(-6) mol l(-1) was obtained. The detection limit of the sensor was calculated equal to 1.5x10(-9) mol l(-1). This sensor was used successfully for TNT determination in different water and soil samples. Copyright 2009 Elsevier B.V. All rights reserved.

Highly selective solid-phase extraction and large volume injection for the robust gas chromatography-mass spectrometric analysis of TCA and TBA in wines.

PubMed

Insa, S; Anticó, E; Ferreira, V

2005-09-30

A reliable solid-phase extraction (SPE) method for the simultaneous determination of 2,4,6-trichloroanisole (TCA) and 2,4,6-tribromoanisole (TBA) in wines has been developed. In the proposed procedure 50 mL of wine are extracted in a 1 mL cartridge filled with 50 mg of LiChrolut EN resins. Most wine volatiles are washed up with 12.5 mL of a water:methanol solution (70%, v/v) containing 1% of NaHCO3. Analytes are further eluted with 0.6 mL of dichloromethane. A 40 microL aliquot of this extract is directly injected into a PTV injector operated in the solvent split mode, and analysed by gas chromatography (GC)-ion trap mass spectrometry using the selected ion storage mode. The solid-phase extraction, including sample volume and rinsing and elution solvents, and the large volume GC injection have been carefully evaluated and optimized. The resulting method is precise (RSD (%) < 6% at 100 ng L(-1)), sensitive (LOD were 0.2 and 0.4 ng/L for TCA and TBA, respectively), robust (the absolute recoveries of both analytes are higher than 80% and consistent wine to wine) and friendly to the GC-MS system (the extract is clean, simple and free from non-volatiles).

Comparison of extraction methods for the analysis of natural dyes in historical textiles by high-performance liquid chromatography.

PubMed

Valianou, Lemonia; Karapanagiotis, Ioannis; Chryssoulakis, Yannis

2009-12-01

Different methods for the extraction of Dactylopius coccus Costa, Rubia tinctorum L., Isatis tinctoria L., Reseda luteola L., Curcuma longa L. and Cotinus coggygria Scop. from wool fibres are investigated using high-performance liquid chromatography with diode array detector (HPLC-DAD). The efficiencies of five extraction methods which include the use of HCl (widely used extraction method), citric acid, oxalic acid, TFA and a combination of HCOOH and EDTA are compared on the basis of the (a) number, (b) relative quantities, measured as HPLC peak areas and (c) signal-to-noise ratios (S/N) of the compounds extracted from the wool substrates. Flavonoid glycosides and curcuminoids contained in R. luteola L. and C. longa L., respectively, according to liquid chromatography with mass spectrometry (LC-MS) identifications, are not detected after treating the fibres with HCl. All the other milder methods are successful in extracting these compounds. Experiments are performed using HPLC-DAD to compare the HPLC peak areas and the S/N of the following extracted compounds: indigotin, indirubin, curcumin, demethoxycurcumin, bisdemethoxycurcumin, fisetin, sulfuretin, luteolin, luteolin-7-O-glucoside, apigenin, carminic acid, alizarin, puruprin and rubiadin. It is shown that the TFA method provides overall the best results as it gives elevated extraction yields except for fisetin, luteolin, apigenin and luteolin-7-O-glucoside and highest S/N except for fisetin and luteolin-7-O-glucoside. It is noteworthy that treatment of the fibres with the typical HCl extraction method results overall in very low S/N. The TFA method is selected for further studies, as follows. First, it is applied on silk dyed samples and compared with the HCl method. The same relative differences of the TFA and HCl methods observed for the wool dyed samples are reported for the silk dyed samples too, except for rubiadin, luteolin and apigenin. Thus, in most cases, the nature of the substrate (wool or silk) appears to have negligible effects on the relative difference of the two extraction methods. Second, the selected TFA method is applied to treat wool and silk historical samples extracted from textiles of the Mamluk period, resulting in the identification of several colouring compounds. In all extraction methods mentioned above, DMSO is used to dissolve the dyes, after acid treatment.

Feature Selection Method Based on Neighborhood Relationships: Applications in EEG Signal Identification and Chinese Character Recognition

PubMed Central

Zhao, Yu-Xiang; Chou, Chien-Hsing

2016-01-01

In this study, a new feature selection algorithm, the neighborhood-relationship feature selection (NRFS) algorithm, is proposed for identifying rat electroencephalogram signals and recognizing Chinese characters. In these two applications, dependent relationships exist among the feature vectors and their neighboring feature vectors. Therefore, the proposed NRFS algorithm was designed for solving this problem. By applying the NRFS algorithm, unselected feature vectors have a high priority of being added into the feature subset if the neighboring feature vectors have been selected. In addition, selected feature vectors have a high priority of being eliminated if the neighboring feature vectors are not selected. In the experiments conducted in this study, the NRFS algorithm was compared with two feature algorithms. The experimental results indicated that the NRFS algorithm can extract the crucial frequency bands for identifying rat vigilance states and identifying crucial character regions for recognizing Chinese characters. PMID:27314346

Metal separation from mixed types of batteries using selective precipitation and liquid-liquid extraction techniques.

PubMed

Provazi, Kellie; Campos, Beatriz Amaral; Espinosa, Denise Crocce Romano; Tenório, Jorge Alberto Soares

2011-01-01

The purpose of this paper is to study metal separation from a sample composed of a mixture of the main types of spent household batteries, using a hydrometallurgical route, comparing selective precipitation and liquid-liquid extraction separation techniques. The preparation of the solution consisted of: grinding the waste of mixed batteries, reduction and volatile metals elimination using electric furnace and acid leaching. From this solution two different routes were studied: selective precipitation with sodium hydroxide and liquid-liquid extraction using Cyanex 272 [bis(2,4,4-trimethylpentyl) phosphoric acid] as extracting agent. The best results were obtained from liquid-liquid extraction in which Zn had a 99% extraction rate at pH 2.5. More than 95% Fe was extracted at pH 7.0, the same pH at which more than 90% Ce was extracted. About 88% Mn, Cr and Co was extracted at this pH. At pH 3.0, more than 85% Ni was extracted, and at pH 3.5 more than 80% of Cd and La was extracted. Copyright © 2010 Elsevier Ltd. All rights reserved.

Selection of propolis Tetragonula sp. extract solvent with flavonoids and polyphenols concentration and antioxidant activity parameters

NASA Astrophysics Data System (ADS)

Christina, Daisy; Hermansyah, Heri; Wijanarko, Anondho; Rohmatin, Etin; Sahlan, Muhamad; Pratami, Diah Kartika; Mun'im, Abdul

2018-02-01

Antioxidants are inhibitory compounds that can inhibit auto oxidation reaction by binding to free radicals and highly reactive molecules. The human body needs antioxidant. Antioxidants can be obtained from a variety of natural ingredients, including propolis. Propolis is the natural sap of the bees, obtained from the herbs around the honeycomb. Ethanol is the solvent that often used to extract propolis. Although it has many advantages, ethanol also has weaknesses such as intolerance to alcohol by some people. Therefore, this research was to extract propolis Tetragonula sp. coarse (C) and soft (S) using four varieties of organic solvent, i.e. olive oil (OO), virgin coconut oil (VCO), propylene glycol (PG), and lecithin (L). It was expected to get the best solvent in extracting propolis. The selection of the best solvent was determined by total flavonoids and polyphenols content assay and antioxidant activity. At each test, the absorbance value read by a microplate reader. Flavonoids content assay is using AlCl3 method with best result on rough-VCO propolis extract of 2509,767 ± 615,02 µg/mL. Polyphenols content assay was using Folin Ciocalteu method with the best results on soft-VCO propolis extract of 1391 ± 171.47 µg/mL. Antioxidant activity assay is using DPPH method with best result on soft-VCO propolis extract with IC50 value of 1,559 ± 0,222 µg/mL.

Evaluation of the effect of extraction solvent and organ selection on the chemical profile of Astragalus spinosus using HPTLC- multivariate image analysis.

PubMed

Shawky, Eman; Selim, Dina A

2017-09-01

The evaluation of extraction protocols for untargeted and targeted metabolomics was implemented for root and aerial organs of Astragalus spinosus in this work. The efficiency and complementarity of commonly used extraction solvents, namely petroleum ether, methylene chloride, ethyl acetate and n-butanol were considered for method evaluation using chemometric techniques in conjunction with new, simple, and fast high performance thin layer chromatography (HPTLC) method for fingerprint analysis by extracting information from a digitalized HPTLC plate using ImageJ software. A targeted approach was furtherly implemented by developing and validating an HPTLC method allowing the quantification of three saponin glycosides. The results of untargeted and targeted principle component analysis (PCA) and hierarchical cluster analysis (HCA) revealed that the apparent saponins profile seems to depend on a combined effect of matrix composition and the properties of the selected solvent for extraction, where both the biological matrix of the investigated plant organs, as well as the extraction solvent can influence the precision of metabolite abundances. Although, the aerial part is frequently discarded as waste, it is shown hereby that it has similar chemical profile compared to the medicinal part, roots, yet a different extraction solvents pattern is recognized between the two organs which can be attributed to the differences in the composition, permeability or accessibility of the sample matrix/organ tissues, rather than the chemical structures of the detected metabolites. Copyright © 2017 Elsevier B.V. All rights reserved.

Extraction of a single Stokes line from a Brillouin fibre laser using a silicon oxynitride microring filter

NASA Astrophysics Data System (ADS)

Zulkifli, M. Z.; Chong, W. Y.; Melloni, A.; Morichetti, F.; Harun, S. W.; Ahmad, H.

2013-09-01

Extraction of a single channel Brillouin Stokes line generated by pumping a length of single mode fibre is demonstrated using a silicon oxynitride microring resonator. The high Q-factor microring resonator has a steep slope transmission profile with an extinction ratio of 20 dB and a free spectral range of 0.4 nm. Experimental results show that extraction of a single Brillouin Stokes line can be achieved with a side mode suppression ratio of more than 12 dB. Additionally, Brillouin Stokes line selection can be achieved by controlling the microring resonance wavelength by thermal tuning.

Separation and purification of thymopentin with molecular imprinting membrane by solid phase extraction disks.

PubMed

Wang, Chaoli; Hu, Xiaoling; Guan, Ping; Wu, Danfeng; Qian, Liwei; Li, Ji; Song, Renyuan

2015-01-01

The synthesis and performance of molecularly imprinted membranes (MIMs) as a solid phase extraction packing materials for the separation and purification of thymopentin from crude samples was described. In order to increase structural selectivity and imprinting efficiency, surface-initiated ATRP and ionic liquid (1-vinyl-3-ethyl acetate imidazolium chloride) were used to prepare molecularly imprinting membranes. The results demonstrated that solid phase extraction disks stuffed by MIMs with ionic liquids as functional monomer demonstrated high isolation and purification of performance to the thymopentin. The molecular recognition of thymopentin was analyzed by using molecular modeling software. Copyright © 2014 Elsevier B.V. All rights reserved.

Selective isolation of hydrophobin SC3 by solid-phase extraction with polytetrafluoroethylene microparticles and subsequent mass spectrometric analysis.

PubMed

Kupčík, Rudolf; Zelená, Miroslava; Řehulka, Pavel; Bílková, Zuzana; Česlová, Lenka

2016-02-01

Hydrophobins are small proteins that play a role in a number of processes during the filamentous fungi growth and development. These proteins are characterized by the self-assembly of their molecules into an amphipathic membrane at hydrophilic-hydrophobic interfaces. Isolation and purification of hydrophobins generally present a challenge in their analysis. Hydrophobin SC3 from Schizophyllum commune was selected as a representative of class I hydrophobins in this work. A novel procedure for selective and effective isolation of hydrophobin SC3 based on solid-phase extraction with polytetrafluoroethylene microparticles loaded in a small self-made microcolumn is reported. The tailored binding of hydrophobins to polytetrafluoroethylene followed by harsh elution conditions resulted in a highly specific isolation of hydrophobin SC3 from the model mixture of ten proteins. The presented isolation protocol can have a positive impact on the analysis and utilization of these proteins including all class I hydrophobins. Hydrophobin SC3 was further subjected to reduction of its highly stable disulfide bonds and to chymotryptic digestion followed by mass spectrometric analysis. The isolation and digestion protocols presented in this work make the analysis of these highly hydrophobic and compact proteins possible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Construction of uniformly sized pseudo template imprinted polymers coupled with HPLC-UV for the selective extraction and determination of trace estrogens in chicken tissue samples.

PubMed

Wang, Shu; Li, Yun; Wu, Xiaoli; Ding, Meijuan; Yuan, Lihua; Wang, Ruoyu; Wen, Tingting; Zhang, Jun; Chen, Lina; Zhou, Xuemin; Li, Fei

2011-02-28

To assess the potential risks associated with the environmental exposure of steroid estrogens, a novel highly efficient and selective estrogen enrichment procedure based on the use of molecularly imprinted polymer has been developed and evaluated. Herein, analogue of estrogens, namely 17-ethyl estradiol (EE(2)) was used as the pseudo template, to avoid the leakage of a trace amount of the target analytes. The resulting pseudo molecularly imprinted polymers (PMIPs) showed large sorption capacity, high recognition ability and fast binding kinetics for estrogens. Moreover, using these imprinted particles as dispersive solid-phase extraction (DSPE) materials, the amounts of three estrogens (E(1), E(2) and E(3)) which were detected by HPLC-UV from the chicken tissue samples were 0.28, 0.31 and 0.17 μg g(-1), and the recoveries were 72.5-78.7%, 90.3-95.2% and 80.5-83.6% in spiked chicken tissue samples with RSD <7%, respectively. All these results reveal that EE(2)-PMIPs as DSPE materials coupled with HPLC-UV could be applied to the highly selective separation and sensitive determination of trace estrogens in chicken tissue samples. Copyright © 2010 Elsevier B.V. All rights reserved.

BMAA extraction of cyanobacteria samples: which method to choose?

PubMed

Lage, Sandra; Burian, Alfred; Rasmussen, Ulla; Costa, Pedro Reis; Annadotter, Heléne; Godhe, Anna; Rydberg, Sara

2016-01-01

β-N-Methylamino-L-alanine (BMAA), a neurotoxin reportedly produced by cyanobacteria, diatoms and dinoflagellates, is proposed to be linked to the development of neurological diseases. BMAA has been found in aquatic and terrestrial ecosystems worldwide, both in its phytoplankton producers and in several invertebrate and vertebrate organisms that bioaccumulate it. LC-MS/MS is the most frequently used analytical technique in BMAA research due to its high selectivity, though consensus is lacking as to the best extraction method to apply. This study accordingly surveys the efficiency of three extraction methods regularly used in BMAA research to extract BMAA from cyanobacteria samples. The results obtained provide insights into possible reasons for the BMAA concentration discrepancies in previous publications. In addition and according to the method validation guidelines for analysing cyanotoxins, the TCA protein precipitation method, followed by AQC derivatization and LC-MS/MS analysis, is now validated for extracting protein-bound (after protein hydrolysis) and free BMAA from cyanobacteria matrix. BMAA biological variability was also tested through the extraction of diatom and cyanobacteria species, revealing a high variance in BMAA levels (0.0080-2.5797 μg g(-1) DW).

Molecularly imprinted sol-gel nanofibers based solid phase microextraction coupled on-line with high performance liquid chromatography for selective determination of acesulfame.

PubMed

Moein, Mohammad Mahdi; Javanbakht, Mehran; Karimi, Mohammad; Akbari-Adergani, Behrouz

2015-03-01

Sol-gel based molecularly imprinted polymer (MIP) nanofiber was successfully fabricated by electrospinning technique on the surface of a stainless steel bar. The manufactured tool was applied for on-line selective solid phase microextraction (SPME) and determination of acesulfame (ACF) as an artificial sweetener with high performance liquid chromatography (HPLC). The selective ability of method for the extraction of ACF was investigated in the presence of some selected sweeteners such as saccharine (SCH), aspartame (ASP) and caffeine (CAF). Electrospinning of MIP sol-gel solution on the stainless steel bar provided an unbreakable sorbent with high thermal, mechanical, and chemical stability. Moreover, application of the MIP-SPME tool revealed a unique approach for the selective microextraction of the analyte in beverage samples. In this work, 3-(triethoxysilyl)-propylamine (TMSPA) was chosen as a precursor due to its ability to imprint the analyte by hydrogen bonding, Van der Walls, and dipole-dipole interactions. Nylon 6 was also added as a backbone and support for the precursor in which sol could greatly growth during the sol-gel process and makes the solution electrospinable. Various effective parameters in the extraction efficiency of the MIP-SPME tool such as loading time, flow rate, desorption time, selectivity, and the sample volume were evaluated. The linearity for the ACF in beverage sample was in the range of 0.78-100.5 ng mL(-1). Limit of detection (LOD) and quantification (LOQ) were 0.23 and 0.78 ng mL(-1) respectively. The RSD values (n=5) were all below 3.5%at the 20 ng mL(-1) level. Copyright © 2014 Elsevier B.V. All rights reserved.

Hybrid genetic algorithm-neural network: feature extraction for unpreprocessed microarray data.

PubMed

Tong, Dong Ling; Schierz, Amanda C

2011-09-01

Suitable techniques for microarray analysis have been widely researched, particularly for the study of marker genes expressed to a specific type of cancer. Most of the machine learning methods that have been applied to significant gene selection focus on the classification ability rather than the selection ability of the method. These methods also require the microarray data to be preprocessed before analysis takes place. The objective of this study is to develop a hybrid genetic algorithm-neural network (GANN) model that emphasises feature selection and can operate on unpreprocessed microarray data. The GANN is a hybrid model where the fitness value of the genetic algorithm (GA) is based upon the number of samples correctly labelled by a standard feedforward artificial neural network (ANN). The model is evaluated by using two benchmark microarray datasets with different array platforms and differing number of classes (a 2-class oligonucleotide microarray data for acute leukaemia and a 4-class complementary DNA (cDNA) microarray dataset for SRBCTs (small round blue cell tumours)). The underlying concept of the GANN algorithm is to select highly informative genes by co-evolving both the GA fitness function and the ANN weights at the same time. The novel GANN selected approximately 50% of the same genes as the original studies. This may indicate that these common genes are more biologically significant than other genes in the datasets. The remaining 50% of the significant genes identified were used to build predictive models and for both datasets, the models based on the set of genes extracted by the GANN method produced more accurate results. The results also suggest that the GANN method not only can detect genes that are exclusively associated with a single cancer type but can also explore the genes that are differentially expressed in multiple cancer types. The results show that the GANN model has successfully extracted statistically significant genes from the unpreprocessed microarray data as well as extracting known biologically significant genes. We also show that assessing the biological significance of genes based on classification accuracy may be misleading and though the GANN's set of extra genes prove to be more statistically significant than those selected by other methods, a biological assessment of these genes is highly recommended to confirm their functionality. Copyright © 2011 Elsevier B.V. All rights reserved.

Dual-wavelength phase-shifting digital holography selectively extracting wavelength information from wavelength-multiplexed holograms.

PubMed

Tahara, Tatsuki; Mori, Ryota; Kikunaga, Shuhei; Arai, Yasuhiko; Takaki, Yasuhiro

2015-06-15

Dual-wavelength phase-shifting digital holography that selectively extracts wavelength information from five wavelength-multiplexed holograms is presented. Specific phase shifts for respective wavelengths are introduced to remove the crosstalk components and extract only the object wave at the desired wavelength from the holograms. Object waves in multiple wavelengths are selectively extracted by utilizing 2π ambiguity and the subtraction procedures based on phase-shifting interferometry. Numerical results show the validity of the proposed technique. The proposed technique is also experimentally demonstrated.

A fully automated method for simultaneous determination of aflatoxins and ochratoxin A in dried fruits by pressurized liquid extraction and online solid-phase extraction cleanup coupled to ultra-high-pressure liquid chromatography-tandem mass spectrometry.

PubMed

Campone, Luca; Piccinelli, Anna Lisa; Celano, Rita; Russo, Mariateresa; Valdés, Alberto; Ibáñez, Clara; Rastrelli, Luca

2015-04-01

According to current demands and future perspectives in food safety, this study reports a fast and fully automated analytical method for the simultaneous analysis of the mycotoxins with high toxicity and wide spread, aflatoxins (AFs) and ochratoxin A (OTA) in dried fruits, a high-risk foodstuff. The method is based on pressurized liquid extraction (PLE), with aqueous methanol (30%) at 110 °C, of the slurried dried fruit and online solid-phase extraction (online SPE) cleanup of the PLE extracts with a C18 cartridge. The purified sample was directly analysed by ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for sensitive and selective determination of AFs and OTA. The proposed analytical procedure was validated for different dried fruits (vine fruit, fig and apricot), providing method detection and quantification limits much lower than the AFs and OTA maximum levels imposed by EU regulation in dried fruit for direct human consumption. Also, recoveries (83-103%) and repeatability (RSD < 8, n = 3) meet the performance criteria required by EU regulation for the determination of the levels of mycotoxins in foodstuffs. The main advantage of the proposed method is full automation of the whole analytical procedure that reduces the time and cost of the analysis, sample manipulation and solvent consumption, enabling high-throughput analysis and highly accurate and precise results.

Trace analysis of selected hormones and sterols in river sediments by liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

PubMed

Matić, Ivana; Grujić, Svetlana; Jauković, Zorica; Laušević, Mila

2014-10-17

In this paper, development and optimization of new LC-MS method for determination of twenty selected hormones, human/animal and plant sterols in river sediments were described. Sediment samples were prepared using ultrasonic extraction and clean up with silica gel/anhydrous sodium sulphate cartridge. Extracts were analyzed by liquid chromatography-linear ion trap-tandem mass spectrometry, with atmospheric pressure chemical ionization. The optimized extraction parameters were extraction solvent (methanol), weight of the sediment (2 g) and time of ultrasonic extraction (3× 10 min). Successful chromatographic separation of hormones (estriol and estrone, 17α- and 17β-estradiol) and four human/animal sterols (epicoprostanol, coprostanol, α-cholestanol and β-cholestanol) that have identical fragmentation reactions was achieved. The developed and optimized method provided high recoveries (73-118%), low limits of detection (0.8-18 ng g(-1)) and quantification (2.5-60 ng g(-1)) with the RSDs generally lower than 20%. Applicability of the developed method was confirmed by analysis of six river sediment samples. A widespread occurrence of human/animal and plant sterols was found. The only detected hormone was mestranol in just one sediment sample. Copyright © 2014 Elsevier B.V. All rights reserved.

The use of fibrous ion exchangers in gold hydrometallurgy

NASA Astrophysics Data System (ADS)

Kautzmann, R. M.; Sampaio, C. H.; Cortina, J. L.; Soldatov, V.; Shunkevich, A.

2002-10-01

This article examines a family of ion-exchange fibers, FIBAN, containing primary and secondary amine groups. These ion exchangers have a fiber diameter of 20 40 Μm, high osmotic and mechanic stability, a high rate of adsorption and regeneration, and excellent dynamic characteristics as filtering media. Inparticular, this article discusses the use of FIBAN fibrous ion exchangers in the recovery of gold cyanide andbase-metal cyanides (copper and mercury) from mineral-leaching solutions. The influence of polymer structure and water content on their extraction ability is described, along with key parameters of gold hydrometallurgy such as extraction efficiency, selectivity, pH dependence, gold cyanide loading, kinetics, and stripping.

Recovery of uranium values

DOEpatents

Brown, K. B.; Crouse, Jr., D. J.; Moore, J. G.

1959-03-10

A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine fn the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected anine dissolved in a nonpolar waterimmiscible organfc solvent such as kerosene. The uranium which is substantially completely extracted by the organic phase may be stripped therefrom by water, and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

Speciation of mercury in sludge solids: washed sludge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bannochie, C. J.; Lourie, A. P.

2017-10-24

The objective of this applied research task was to study the type and concentration of mercury compounds found within the contaminated Savannah River Site Liquid Waste System (SRS LWS). A method of selective sequential extraction (SSE), developed by Eurofins Frontier Global Sciences1,2 and adapted by SRNL, utilizes an extraction procedure divided into seven separate tests for different species of mercury. In the SRNL’s modified procedure four of these tests were applied to a washed sample of high level radioactive waste sludge.

Imprinted magnetic graphene oxide for the mini-solid phase extraction of Eu (III) from coal mine area

NASA Astrophysics Data System (ADS)

Patra, Santanu; Roy, Ekta; Madhuri, Rashmi; Sharma, Prashant K.

2017-05-01

The present work represents the preparation of imprinted magnetic reduced graphene oxide and applied it for the selective removal of Eu (III) from local coal mines area. A simple solid phase extraction method was used for this purpose. The material shows a very high adsorption as well as removal efficiency towards Eu (III), which suggest that the material have potential to be used in future for their real time applications in removal of Eu (III) from complex matrices.

Human Gongylonema pulchrum Infection: Esophageal Symptoms and Need for Prolonged Albendazole Therapy.

PubMed

Libertin, Claudia R; Reza, Mohammed; Peterson, Joy H; Lewis, Jason; Hata, D Jane

2017-04-01

AbstractWe describe a case of human infection with Gongylonema pulchrum acquired in southeast Georgia. The patient presented with intermittent yet persistent nausea and vomiting for months. This case describes the need for extraction of worms on two occasions each followed by courses of albendazole treatment. Gongylonema pulchrum infections with high worm burden may relapse after extraction of the worm and a 3-day short course of albendazole therapy. Longer courses of albendazole may be indicated in selected circumstances.

Thermospray ionization liquid chromatography-mass spectrometry and chemical ionization gas chromatography- mass spectrometry of hexazinone metabolites in soil and vegetation extracts

Treesearch

Joseph B. Fischer; Jerry L. Michael

1995-01-01

We have used thermospray LC-MS to confirm three highly polar metabolites (A, B. and G) of the herbicide hexazinone [3-cyclohexyl-6-(dimethylamino)-l-methyl-1,3,5-triazine-2,4(1H,3H)-dione]. and chemical ionization GC-MS to confirm two other metabolites (D and E) in extracts of soil and vegetation from a forest in the Central Alabama Piedmont. Selected-ion monitoring (...

Comparison of three different dispersive liquid-liquid microextraction modes performed on their most usual configurations for the extraction of phenolic, neutral aromatic, and amino compounds from waters.

PubMed

Saraji, Mohammad; Ghambari, Hoda

2018-06-21

In this work we seek clues to select the appropriate dispersive liquid-liquid microextraction mode for extracting three categories of compounds. For this purpose, three common dispersive liquid-liquid microextraction modes were compared under optimized conditions. Traditional dispersive liquid-liquid microextraction, in situ ionic liquid dispersive liquid-liquid microextraction and conventional ionic liquid dispersive liquid-liquid microextraction using chloroform, 1-butyl-3-methylimidazolium tetrafluoroborate, and 1-hexyl-3-methylimidazolium hexafluorophosphate as the extraction solvent, respectively, were considered in this work. Phenolic, neutral aromatic and amino compounds (each category included six members) were studied as analytes. The analytes in the extracts were determined by high-performance liquid chromatography with UV detection. For the analytes with polar functionalities, the in situ ionic liquid dispersive liquid-liquid microextraction mode mostly led to better results. In contrast, for neutral hydrocarbons without polar functionalities, traditional dispersive liquid-liquid microextraction using chloroform produced better results. In this case, where dispersion forces were the dominant interactions in the extraction, the refractive index of solvent and analyte predicted the extraction performance better than the octanol-water partition coefficient. It was also revealed that none of the methods were successful in extracting very hydrophilic analytes (compounds with the log octanol-water partition coefficient < 2). The results of this study could be helpful in selecting a dispersive liquid-liquid microextraction mode for the extraction of various groups of compounds. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Evaluation of Radical Scavenging Activity of Sempervivum tectorum and Corylus avellana Extracts with Different Phenolic Composition.

PubMed

Alberti, Ágnes; Riethmüller, Eszter; Béni, Szabolcs; Kéry, Ágnes

2016-04-01

Semnpervivum tectorum L. and Corylus avellana L. are traditional herbal remedies exhibiting antioxidant activity and representing diverse phenolic composition. The aim of this study was to reveal the contribution of certain compounds to total radical scavenging activity by studying S. tectorum and C. avellana extracts prepared with solvents of different selectivity for diverse classes of phenolics. Antioxidant activity of S. tectorum and C. avellana samples was determined in the ABTS and DPPH radical scavenging assays, and phenolic composition was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Correlations between antioxidant activity and phenolic content of houseleek extracts have been revealed. Significant differences regarding antioxidant activity have been shown between S. tectorum 80% (v/v) methanol extract and its fractions. Additionally, synergism among the constituents present together in the whole extract was assumed. Significantly higher radical scavenging activity of hazel extracts has been attributed to the differences in phenolic composition compared with houseleek extracts.

Method of simultaneous stir bar sorptive extraction of phenethylamines and THC metabolite from urine.

PubMed

Goto, Yoshiyuki; Takeda, Shiho; Araki, Toshinori; Fuchigami, Takayuki

2011-10-01

Stir bar sorptive extraction is a technique used for extracting target substances from various aqueous matrixes such as environmental water, food, and biological samples. This type of extraction is carried out by rotating a coated stir bar is rotated in the sample solution. In particular, Twister bar is a commercial stir bar that is coated with polydimethylsiloxane (PDMS) and used to perform sorptive extraction. In this study, we developed a method for simultaneous detection of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and a Δ(9)-tetrahydrocannabiniol (THC) metabolite in human urine. For extracting the target analytes, the Twister bar was simply stirred in the sample in the presence of a derivatizing agent. Using this technique, phenethylamines and the acidic THC metabolite can be simultaneously extracted from human urine. This method also enables the extraction of trace amounts of these substances with good reproducibility and high selectivity. The proposed method offers many advantages over other extraction-based approaches and is therefore well suited for screening psychoactive substances in urine specimens.

Extraction of carotenoids and chlorophyll from microalgae with supercritical carbon dioxide and ethanol as cosolvent.

PubMed

Macías-Sánchez, Maria Dolores; Mantell Serrano, Casimiro; Rodríguez Rodríguez, Miguel; Martínez de la Ossa, Enrique; Lubián, Luís M; Montero, Olimpio

2008-05-01

The extraction of carotenoids and chlorophylls using carbon dioxide modified with ethanol as a cosolvent is an alternative to solvent extraction because it provides a high-speed extraction process. In the study described here, carotenoid and chlorophyll extraction with supercritical CO(2 )+ ethanol was explored using freeze-dried powders of three microalgae (Nannochloropsis gaditana, Synechococcus sp. and Dunaliella salina) as the raw materials. The operation conditions were as follows: pressures of 200, 300, 400 and 500 bar, temperatures of 40, 50 and 60 degrees C. Analysis of the extracts was performed by measuring the absorbance and by using empirical correlations. The results demonstrate that it is necessary to work at a temperature of 50-60 degrees C and a pressure range of 300-500 bar, depending on the type of microalgae, in order to obtain the highest yield of pigments. The best carotenoid/chlorophyll ratios were obtained by using supercritical fluid extraction + cosolvent instead of using conventional extraction. The higher selectivity of the former process should facilitate the separation and purification of the two extracted pigments.

Evaluation of DNA extraction methods for the analysis of microbial community in biological activated carbon.

PubMed

Zheng, Lu; Gao, Naiyun; Deng, Yang

2012-01-01

It is difficult to isolate DNA from biological activated carbon (BAC) samples used in water treatment plants, owing to the scarcity of microorganisms in BAC samples. The aim of this study was to identify DNA extraction methods suitable for a long-term, comprehensive ecological analysis of BAC microbial communities. To identify a procedure that can produce high molecular weight DNA, maximizes detectable diversity and is relatively free from contaminants, the microwave extraction method, the cetyltrimethylammonium bromide (CTAB) extraction method, a commercial DNA extraction kit, and the ultrasonic extraction method were used for the extraction of DNA from BAC samples. Spectrophotometry, agarose gel electrophoresis and polymerase chain reaction (PCR)-restriction fragment length polymorphisms (RFLP) analysis were conducted to compare the yield and quality of DNA obtained using these methods. The results showed that the CTAB method produce the highest yield and genetic diversity of DNA from BAC samples, but DNA purity was slightly less than that obtained with the DNA extraction-kit method. This study provides a theoretical basis for establishing and selecting DNA extraction methods for BAC samples.

Validated semiquantitative/quantitative screening of 51 drugs in whole blood as silylated derivatives by gas chromatography-selected ion monitoring mass spectrometry and gas chromatography electron capture detection.

PubMed

Gunnar, Teemu; Mykkänen, Sirpa; Ariniemi, Kari; Lillsunde, Pirjo

2004-07-05

A comprehensively validated procedure is presented for simultaneous semiquantitative/quantitative screening of 51 drugs of abuse or drugs potentially hazardous for traffic safety in serum, plasma or whole blood. Benzodiazepines (12), cannabinoids (3), opioids (8), cocaine, antidepressants (13), antipsychotics (5) and antiepileptics (2) as well as zolpidem, zaleplon, zopiclone, meprobamate, carisoprodol, tizanidine and orphenadrine and internal standard flurazepam, were isolated by high-yield liquid-liquid extraction (LLE). The dried extracts were derivatized by two-step silylation and analyzed by the combination of two different gas chromatographic (GC) separations with both electron capture detection (ECD) and mass spectrometry (MS) operating in a selected ion-monitoring (SIM) mode. Quantitative or semiquantitative results were obtained for each substance based on four-point calibration. In the validation tests, accuracy, reproducibility, linearity, limit of detection (LOD) and limit of quantitation (LOQ), selectivity, as well as extraction efficiency and stability of standard stock solutions were tested, and derivatization was optimized in detail. Intra- and inter-day precisions were within 2.5-21.8 and 6.0-22.5%, and square of correlation coefficients of linearity ranged from 0.9896 to 0.9999. The limit of quantitation (LOQ) varied from 2 to 2000 ng/ml due to a variety of the relevant concentrations of the analyzed substances in blood. The method is feasible for highly sensitive, reliable and possibly routinely performed clinical and forensic toxicological analyses.

Selective and rapid determination of tadalafil and finasteride using solid phase extraction by high performance liquid chromatography and tandem mass spectrometry.

PubMed

Pappula, Nagaraju; Kodali, Balaji; Datla, Peda Varma

2018-04-15

Highly selective and fast liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for simultaneous determination of tadalafil (TDL) and finasteride (FNS) in human plasma. The method was successfully applied for analysis of TDL and FNS samples in clinical study. The method was validated as per USFDA (United States Food and Drug Administration), EMA (European Medicines Agency), and ANVISA (Agência Nacional de Vigilância Sanitária-Brazil) bio analytical method validation guidelines. Glyburide (GLB) was used as common internal standard (ISTD) for both analytes. The selected multiple reaction monitoring (MRM) transitions for mass spectrometric analysis were m/z 390.2/268.2, m/z 373.3/305.4 and m/z 494.2/369.1 for TDL, FNS and ISTD respectively. The extraction of analytes and ISTD was accomplished by a simple solid phase extraction (SPE) procedure. Rapid analysis time was achieved on Zorbax Eclipse C18 column (50 × 4.6 mm, 5 μm). The calibration ranges for TDL and FNS were 5-800 ng/ml and 0.2-30 ng/ml respectively. The results of precision and accuracy, linearity, recovery and matrix effect of the method are acceptable. The accuracy was in the range of 92.9%-106.4% and method precision was also good; %CV was less than 8.1%. Copyright © 2018 Elsevier B.V. All rights reserved.

Synthesis of Quercetin-imprinted Polymer Spherical Particles with Improved Ability to Capture Quercetin Analogues.

PubMed

Pardo, Antonelle; Josse, Thomas; Mespouille, Laetitia; Blankert, Bertrand; Dubois, Philippe; Duez, Pierre

2017-07-01

Molecularly imprinted polymers (MIPs) are composed of specific cavities able to selectively recognise a template molecule. Used as chromatographic sorbents, MIPs may not trap related structures due to the high rigidity of their cross-linking. To improve the capture of quercetin analogues by modulating the synthesis strategy for a quercetin-imprinted polymer (Qu MIP). An additional comonomer bearing a short oligoethylene glycol (OEG) unit was used to prepare a Qu MIP that was compared to a traditional one formulated in a similar fashion, but without the OEG-comonomer. The Qu MIPs were prepared in bead form through fluorocarbon suspension polymerisation. After solid phase extraction (SPE) assessment of their imprinted cavities, the MIPs were evaluated by HPLC for their recognition properties towards quercetin and other polyphenols, including flavonoids, phenolic acids and curcumin. The Qu MIPs were finally SPE-tested on a white onion extract. The incorporation of OEG units modulated the selectivity of the Qu MIP by improving the recognition of quercetin related structures (12-61% increase in the imprinting effect for distant analogues). It also allowed limiting or suppressing non-specific hydrophobic interactions (decrease of about 10% in the rate of quercetin retention on the non-imprinted polymer). The SPE application of the MIP to a white onion extract indicates its interest for the selective extraction of quercetin and its analogues. The OEG-modified Qu MIP appears to be an attractive tool to discover new drug candidates from natural sources by extracting, amongst interfering compounds, structural analogues of quercetin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Selective extraction and recovery of rare earth metals from phosphor powders in waste fluorescent lamps using an ionic liquid system.

PubMed

Yang, Fan; Kubota, Fukiko; Baba, Yuzo; Kamiya, Noriho; Goto, Masahiro

2013-06-15

The recycling of rare earth metals from phosphor powders in waste fluorescent lamps by solvent extraction using ionic liquids was studied. Acid leaching of rare earth metals from the waste phosphor powder was examined first. Yttrium (Y) and europium (Eu) dissolved readily in the acid solution; however, the leaching of other rare earth metals required substantial energy input. Ionization of target rare earth metals from the waste phosphor powders into the leach solution was critical for their successful recovery. As a high temperature was required for the complete leaching of all rare earth metals, ionic liquids, for which vapor pressure is negligible, were used as an alternative extracting phase to the conventional organic diluent. An extractant, N, N-dioctyldiglycol amic acid (DODGAA), which was recently developed, showed a high affinity for rare earth metal ions in liquid-liquid extraction although a conventional commercial phosphonic extractant did not. An effective recovery of the rare earth metals, Y, Eu, La and Ce, from the metal impurities, Fe, Al and Zn, was achieved from the acidic leach solution of phosphor powders using an ionic liquid containing DODGAA as novel extractant system. Copyright © 2013 Elsevier B.V. All rights reserved.

Glacier Frontal Line Extraction from SENTINEL-1 SAR Imagery in Prydz Area

NASA Astrophysics Data System (ADS)

Li, F.; Wang, Z.; Zhang, S.; Zhang, Y.

2018-04-01

Synthetic Aperture Radar (SAR) can provide all-day and all-night observation of the earth in all-weather conditions with high resolution, and it is widely used in polar research including sea ice, sea shelf, as well as the glaciers. For glaciers monitoring, the frontal position of a calving glacier at different moments of time is of great importance, which indicates the estimation of the calving rate and flux of the glaciers. In this abstract, an automatic algorithm for glacier frontal extraction using time series Sentinel-1 SAR imagery is proposed. The technique transforms the amplitude imagery of Sentinel-1 SAR into a binary map using SO-CFAR method, and then frontal points are extracted using profile method which reduces the 2D binary map to 1D binary profiles, the final frontal position of a calving glacier is the optimal profile selected from the different average segmented profiles. The experiment proves that the detection algorithm for SAR data can automatically extract the frontal position of glacier with high efficiency.

Experimental laboratory measurement of thermophysical properties of selected coal types

NASA Technical Reports Server (NTRS)

Lloyd, W. G.

1979-01-01

A number of bituminous coals of moderate to high plasticity were examined, along with portions of their extrudates from the JPL 1.5-inch 850 F screw extruder. Portions of the condensed pyrolysis liquids released during extrusion, and of the gaseous products formed during extrusion were also analyzed. In addition to the traditional determinations, the coals and extrudates were examined in terms of microstructure (especially extractable fractions), thermal analysis (especially that associated with the plastic state), and reactivity towards thermal and catalyzed hydroliquefaction. The process of extrusion increases the fixed carbon content of coals by about 5% and tends to increase the surface area. Coals contaning 25% or more DMF-extractable material show an increase in extractables as a result of extrusion; those initially containing less than 20% extractables show a decrease as a result of extrusion. Both the raw and extruded samples of Kentucky #9 coal are highly reactive towards hydroliquefaction, undergoing conversions of 75 to 80% in 15 min and 85-94% in 60 min in a stirred clave.

Nelumbo nucifera leaves extracts inhibit mouse airway smooth muscle contraction.

PubMed

Yang, Xiao; Xue, Lu; Zhao, Qingyang; Cai, Congli; Liu, Qing-Hua; Shen, Jinhua

2017-03-20

Alkaloids extracted from lotus leaves (AELL) can relax vascular smooth muscle. However, whether AELL has a similar relaxant role on airway smooth muscle (ASM) remains unknown. This study aimed to explore the relaxant property of AELL on ASM and the underlying mechanism. Alkaloids were extracted from dried lotus leaves using the high temperature rotary evaporation extraction method. The effects of AELL on mouse ASM tension were studied using force measuring and patch-clamp techniques. It was found that AELL inhibited the high K + or acetylcholine chloride (ACh)-induced precontraction of mouse tracheal rings by 64.8 ± 2.9%, or 48.8 ± 4.7%, respectively. The inhibition was statistically significant and performed in a dose-dependent manner. Furthermore, AELL-induced smooth muscle relaxation was partially mediated by blocking voltage-dependent Ca 2+ channels (VDCC) and non-selective cation channels (NSCC). AELL, which plays a relaxant role in ASM, might be a new complementary treatment to treat abnormal contractions of the trachea and asthma.

Process for the extraction of strontium from acidic solutions

DOEpatents

Horwitz, E.P.; Dietz, M.L.

1994-09-06

The invention is a process for selectively extracting strontium values from aqueous nitric acid waste solutions containing these and other fission product values. The extractant solution is a macrocyclic polyether in an aliphatic hydrocarbon diluent containing a phase modifier. The process will selectively extract strontium values from nitric acid solutions which are up to 6 molar in nitric acid. 4 figs.

Process for the extraction of strontium from acidic solutions

DOEpatents

Horwitz, E. Philip; Dietz, Mark L.

1994-01-01

The invention is a process for selectively extracting strontium values from aqueous nitric acid waste solutions containing these and other fission product values. The extractant solution is a macrocyclic polyether in an aliphatic hydrocarbon diluent containing a phase modifier. The process will selectively extract strontium values from nitric acid solutions which are up to 6 molar in nitric acid.

Process for the extraction of strontium from acidic solutions

DOEpatents

Horwitz, E.P.; Dietz, M.L.

1993-01-01

The invention is a process for selectively extracting strontium values from aqueous nitric acid waste solutions containing these and other fission product values. The extractant solution is a macrocyclic polyether in an aliphatic hydrocarbon diluent containing a phase modifier. The process will selectively extract strontium values from nitric acid solutions which are up to 6 molar in nitric acid.

Composition and Molecular Weight Distribution of Carob Germ Proteins Fractions

USDA-ARS?s Scientific Manuscript database

Biochemical properties of carob germ proteins were analyzed using a combination of selective extraction, reversed-phase high performance liquid chromatography (RP-HPLC), size exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALS) and electrophoretic analysis. Using a mo...

Immunologically-based methods for detecting masked mycotoxins

USDA-ARS?s Scientific Manuscript database

Masked mycotoxins are generally described as including unknown mycotoxins, non-extractable forms of known mycotoxins, or untargeted forms of known mycotoxins. Immunoassays can be developed with either broad cross-reaction to mycotoxin congeners or with high selectivity for a particular toxin. The re...

Regulation of cytochrome P450 mRNA expression in primary porcine hepatocytes by selected secondary plant metabolites from chicory (Cichorium intybus L.).

PubMed

Rasmussen, Martin Krøyer; Klausen, Christina Lindgaard; Ekstrand, Bo

2014-03-01

Chicory (Cichorium intybus) has been shown to induce enzymes of pharmacokinetic relevance (cytochrome P450; CYP). The aim of this study was to investigate the effects of selected secondary plant metabolites with a global extract of chicory root, on the expression of hepatic CYP mRNA (1A2, 2A19, 2C33, 2D25, 2E1 and 3A29), using primary porcine hepatocytes. Of the tested secondary plant metabolites, artemisinin, scoparone, lactucin and esculetin all induced increased expression of specific CYPs, while esculin showed no effect. In contrast, a global extract of chicory root decreased the expression of CYP1A2, 2C33, 2D25 and 3A29 at high concentrations. The results suggest that purified secondary metabolites from chicory affect CYP expression and thereby might affect detoxification in general, and that global extracts of plants can have effects different from individual components. Copyright © 2013 Elsevier Ltd. All rights reserved.

Matrine- and oxymatrine-imprinted monodisperse polymers prepared by precipitation polymerization and their applications for the selective extraction of matrine-type alkaloids from Sophora flavescens Aiton.

PubMed

Funaya, Noriko; Haginaka, Jun

2012-07-27

Matrine (MT)- and oxymatrine (OMT)-imprinted monodisperse polymers have been prepared by precipitation polymerization. The prepared molecularly imprinted polymers (MIPs) for MT and OMT, MIP(MT) and MIP(OMT), were monodispersed microspheres of 3.3 and 3.9 μm in diameter, respectively. Binding experiments and Scatchard analyses revealed that two classes of binding sites were formed on MIP(MT) and MIP(OMT). In addition to shape recognition, ionic and hydrophobic interactions seemed to affect the retention and recognition of MT and OMT on MIP(MT) and MIP(OMT), respectively, in low acetonitrile content, and ionic and hydrophilic interactions affected these properties in high acetonitrile content. MIP(MT) was used to selectively extract MT and sophocarpine (13,14-dehydromatrine) from Sophora flavescens root, while MIP(OMT) was used to extract OMT and oxysophocarpine (13,14-dehydrooxymatrine). Copyright © 2012 Elsevier B.V. All rights reserved.

Rapid determination of anti-estrogens by gas chromatography/mass spectrometry in urine: Method validation and application to real samples.

PubMed

Gerace, E; Salomone, A; Abbadessa, G; Racca, S; Vincenti, M

2012-02-01

A fast screening protocol was developed for the simultaneous determination of nine anti-estrogenic agents (aminoglutethimide, anastrozole, clomiphene, drostanolone, formestane, letrozole, mesterolone, tamoxifen, testolactone) plus five of their metabolites in human urine. After an enzymatic hydrolysis, these compounds can be extracted simultaneously from urine with a simple liquid-liquid extraction at alkaline conditions. The analytes were subsequently analyzed by fast-gas chromatography/mass spectrometry (fast-GC/MS) after derivatization. The use of a short column, high-flow carrier gas velocity and fast temperature ramping produced an efficient separation of all analytes in about 4 min, allowing a processing rate of 10 samples/h. The present analytical method was validated according to UNI EN ISO/IEC 17025 guidelines for qualitative methods. The range of investigated parameters included the limit of detection, selectivity, linearity, repeatability, robustness and extraction efficiency. High MS-sampling rate, using a benchtop quadrupole mass analyzer, resulted in accurate peak shape definition under both scan and selected ion monitoring modes, and high sensitivity in the latter mode. Therefore, the performances of the method are comparable to the ones obtainable from traditional GC/MS analysis. The method was successfully tested on real samples arising from clinical treatments of hospitalized patients and could profitably be used for clinical studies on anti-estrogenic drug administration.

Rapid determination of anti-estrogens by gas chromatography/mass spectrometry in urine: Method validation and application to real samples

PubMed Central

Gerace, E.; Salomone, A.; Abbadessa, G.; Racca, S.; Vincenti, M.

2011-01-01

A fast screening protocol was developed for the simultaneous determination of nine anti-estrogenic agents (aminoglutethimide, anastrozole, clomiphene, drostanolone, formestane, letrozole, mesterolone, tamoxifen, testolactone) plus five of their metabolites in human urine. After an enzymatic hydrolysis, these compounds can be extracted simultaneously from urine with a simple liquid–liquid extraction at alkaline conditions. The analytes were subsequently analyzed by fast-gas chromatography/mass spectrometry (fast-GC/MS) after derivatization. The use of a short column, high-flow carrier gas velocity and fast temperature ramping produced an efficient separation of all analytes in about 4 min, allowing a processing rate of 10 samples/h. The present analytical method was validated according to UNI EN ISO/IEC 17025 guidelines for qualitative methods. The range of investigated parameters included the limit of detection, selectivity, linearity, repeatability, robustness and extraction efficiency. High MS-sampling rate, using a benchtop quadrupole mass analyzer, resulted in accurate peak shape definition under both scan and selected ion monitoring modes, and high sensitivity in the latter mode. Therefore, the performances of the method are comparable to the ones obtainable from traditional GC/MS analysis. The method was successfully tested on real samples arising from clinical treatments of hospitalized patients and could profitably be used for clinical studies on anti-estrogenic drug administration. PMID:29403714

Rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection.

PubMed

Yang, Xiao; Diao, Chun-Peng; Sun, Ai-Ling; Liu, Ren-Min

2014-10-01

A method for the rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection was proposed in this paper. A simple apparatus consisting of a test tube and a cut-glass dropper was designed and applied to collect the floating extraction drop in liquid-liquid microextraction when low-density organic solvent was used as the extraction solvent. Solidification and melting steps that were tedious but necessary once the low-density organic solvent used as extraction solvent could be avoided by using this apparatus. Bisphenol A was selected as model pollutant and vortex-assisted liquid-liquid microextraction was employed to investigate the usefulness of the apparatus. High-performance liquid chromatography with fluorescence detection was selected as the analytical tool for the detection of bisphenol A. The linear dynamic range was from 0.10 to 100 μg/L for bisphenol A, with good squared regression coefficient (r(2) = 0.9990). The relative standard deviation (n = 7) was 4.7% and the limit of detection was 0.02 μg/L. The proposed method had been applied to the determination of bisphenol A in natural water samples and was shown to be economical, fast, and convenient. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation of magnetic molecularly imprinted polymers by atom transfer radical polymerization for the rapid extraction of avermectin from fish samples.

PubMed

You, Xiaoxiao; Gao, Lei; Qin, Dongli; Chen, Ligang

2017-01-01

A novel and highly efficient approach to obtain magnetic molecularly imprinted polymers is described to detect avermectin in fish samples. The magnetic molecularly imprinted polymers were synthesized by surface imprinting polymerization using magnetic multiwalled carbon nanotubes as the support materials, atom transfer radical polymerization as the polymerization method, avermectin as template, acrylamide as functional monomer, and ethylene glycol dimethacrylate as crosslinker. The characteristics of the magnetic molecularly imprinted polymers were assessed by using transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, vibrating sample magnetometry, X-ray diffraction, and thermogravimetric analysis. The binding characteristics of magnetic molecularly imprinted polymers were researched through isothermal adsorption experiment, kinetics adsorption experiment, and the selectivity experiment. Coupled with ultra high performance liquid chromatography and tandem mass spectrometry, the extraction conditions of the magnetic molecularly imprinted polymers as adsorbents for avermectin were investigated in detail. The recovery of avermectin was 84.2-97.0%, and the limit of detection was 0.075 μg/kg. Relative standard deviations of intra- and inter-day precisions were in the range of 1.7-2.9% and 3.4-5.6%, respectively. The results demonstrated that the extraction method not only has high selectivity and accuracy, but also is convenient for the determination of avermectin in fish samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

19.2% Efficient InP Heterojunction Solar Cell with Electron-Selective TiO 2 Contact

DOE PAGES

Yin, Xingtian; Battaglia, Corsin; Lin, Yongjing; ...

2014-09-25

We demonstrate an InP heterojunction solar cell employing an ultrathin layer (~10 nm) of amorphous TiO 2 deposited at 120°C by atomic layer deposition as the transparent electron-selective contact. The TiO 2 film selectively extracts minority electrons from the conduction band of p-type InP while blocking the majority holes due to the large valence band offset, enabling a high maximum open-circuit voltage of 785 mV. Lastly, a hydrogen plasma treatment of the InP surface drastically improves the long-wavelength response of the device, resulting in a high short-circuit current density of 30.5 mA/cm 2 and a high power conversion efficiency ofmore » 19.2%.« less

The use of chemometrics to study multifunctional indole alkaloids from Psychotria nemorosa (Palicourea comb. nov.). Part I: Extraction and fractionation optimization based on metabolic profiling.

PubMed

Klein-Júnior, Luiz C; Viaene, Johan; Salton, Juliana; Koetz, Mariana; Gasper, André L; Henriques, Amélia T; Vander Heyden, Yvan

2016-09-09

Extraction methods evaluation to access plants metabolome is usually performed visually, lacking a truthful method of data handling. In the present study the major aim was developing reliable time- and solvent-saving extraction and fractionation methods to access alkaloid profiling of Psychotria nemorosa leaves. Ultrasound assisted extraction was selected as extraction method. Determined from a Fractional Factorial Design (FFD) approach, yield, sum of peak areas, and peak numbers were rather meaningless responses. However, Euclidean distance calculations between the UPLC-DAD metabolic profiles and the blank injection evidenced the extracts are highly diverse. Coupled with the calculation and plotting of effects per time point, it was possible to indicate thermolabile peaks. After screening, time and temperature were selected for optimization, while plant:solvent ratio was set at 1:50 (m/v), number of extractions at one and particle size at ≤180μm. From Central Composite Design (CCD) results modeling heights of important peaks, previously indicated by the FFD metabolic profile analysis, time was set at 65min and temperature at 45°C, thus avoiding degradation. For the fractionation step, a solid phase extraction method was optimized by a Box-Behnken Design (BBD) approach using the sum of peak areas as response. Sample concentration was consequently set at 150mg/mL, % acetonitrile in dichloromethane at 40% as eluting solvent, and eluting volume at 30mL. Summarized, the Euclidean distance and the metabolite profiles provided significant responses for accessing P. nemorosa alkaloids, allowing developing reliable extraction and fractionation methods, avoiding degradation and decreasing the required time and solvent volume. Copyright © 2016 Elsevier B.V. All rights reserved.

Criteria to Extract High-Quality Protein Data Bank Subsets for Structure Users.

PubMed

Carugo, Oliviero; Djinović-Carugo, Kristina

2016-01-01

It is often necessary to build subsets of the Protein Data Bank to extract structural trends and average values. For this purpose it is mandatory that the subsets are non-redundant and of high quality. The first problem can be solved relatively easily at the sequence level or at the structural level. The second, on the contrary, needs special attention. It is not sufficient, in fact, to consider the crystallographic resolution and other feature must be taken into account: the absence of strings of residues from the electron density maps and from the files deposited in the Protein Data Bank; the B-factor values; the appropriate validation of the structural models; the quality of the electron density maps, which is not uniform; and the temperature of the diffraction experiments. More stringent criteria produce smaller subsets, which can be enlarged with more tolerant selection criteria. The incessant growth of the Protein Data Bank and especially of the number of high-resolution structures is allowing the use of more stringent selection criteria, with a consequent improvement of the quality of the subsets of the Protein Data Bank.

Simultaneous determination of sulfonamides, tetracyclines and tiamulin in swine wastewater by solid-phase extraction and liquid chromatography-mass spectrometry.

PubMed

Ben, Weiwei; Qiang, Zhimin; Adams, Craig; Zhang, Heqing; Chen, Liping

2008-08-22

Little is known about the contamination level of antibiotics in swine wastewater in China. The highly complex matrix of swine wastewater, which generally has a chemical oxygen demand (COD) concentration as high as 15,000 mg/L, makes it difficult to detect antibiotics at trace levels. In this work, a highly selective and sensitive analytical method was developed for simultaneous determination of three classes of commonly used veterinary antibiotics including five sulfonamides, three tetracyclines and one macrolide in swine wastewater using solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS). The method detection limits (MDL) in the swine wastewater were determined to be between 5 and 91 ng/L, depending on specific antibiotics. Except sulfamethizole, all the other eight antibiotics were detected in the swine wastewaters collected from three concentrated swine feeding plants located in the Beijing (China) area, showing a concentration range of 0.62-32.67 microg/L. These results reveal the representative concentration levels of selected antibiotics in the swine wastewaters of Beijing area.

Wide-Scope Screening Method for Multiclass Veterinary Drug Residues in Fish, Shrimp, and Eel Using Liquid Chromatography-Quadrupole High-Resolution Mass Spectrometry.

PubMed

Turnipseed, Sherri B; Storey, Joseph M; Lohne, Jack J; Andersen, Wendy C; Burger, Robert; Johnson, Aaron S; Madson, Mark R

2017-08-30

A screening method for veterinary drug residues in fish, shrimp, and eel using LC with a high-resolution MS instrument has been developed and validated. The method was optimized for over 70 test compounds representing a variety of veterinary drug classes. Tissues were extracted by vortex mixing with acetonitrile acidified with 2% acetic acid and 0.2% p-toluenesulfonic acid. A centrifuged portion of the extract was passed through a novel solid phase extraction cartridge designed to remove interfering matrix components from tissue extracts. The eluent was then evaporated and reconstituted for analysis. Data were collected with a quadrupole-Orbitrap high-resolution mass spectrometer using both nontargeted and targeted acquisition methods. Residues were detected on the basis of the exact mass of the precursor and a product ion along with isotope pattern and retention time matching. Semiquantitative data analysis compared MS 1 signal to a one-point extracted matrix standard at a target testing level. The test compounds were detected and identified in salmon, tilapia, catfish, shrimp, and eel extracts fortified at the target testing levels. Fish dosed with selected analytes and aquaculture samples previously found to contain residues were also analyzed. The screening method can be expanded to monitor for an additional >260 veterinary drugs on the basis of exact mass measurements and retention times.

Extraction of nobiletin from Citrus Unshiu peels by supercritical fluid and its CRE-mediated transcriptional activity.

PubMed

Oba, Chisato; Ota, Masaki; Nomura, Koichiro; Fujiwara, Hironori; Takito, Jiro; Sato, Yoshiyuki; Ohizumi, Yasushi; Inomata, Hiroshi

2017-04-15

Polymethoxyflavone (PMF) is one of bioactive compounds in Citrus Unshiu and included mainly in the peels rather than the fruits, seeds and leaves. Supercritical CO 2 extraction is one candidate for selective extraction of polymethoxyflavone and in this study, supercritical CO 2 extraction with/without ethanol entrainer from Citrus Unshiu peels was examined at a temperature of 333K and a pressure of 30MPa. CRE (cyclic AMP response element)-mediated transcriptional assay was examined by using the extracts from supercritical fluid extraction. The results showed that extracts including nobiletin increased with increasing ethanol concentration in supercritical CO 2 and the elapsed extraction time. Extracts at ethanol concentration of 5 mol% showed high CRE-mediated transcription activity. This can be caused by activity of the extract including nobiletin in addition to the other methoxylated flavonoid species such as tangeretin. Extracts at ethanol concentration of 50% showed the highest CRE-mediated transcription activity, which can be attributed to flavonoid glycoside such as hesperidin. From our investigations, flavonoid glycoside can be one of promoters of CRE-mediated transcription activity. Copyright © 2017 Elsevier GmbH. All rights reserved.

Effects of band selection on endmember extraction for forestry applications

NASA Astrophysics Data System (ADS)

Karathanassi, Vassilia; Andreou, Charoula; Andronis, Vassilis; Kolokoussis, Polychronis

2014-10-01

In spectral unmixing theory, data reduction techniques play an important role as hyperspectral imagery contains an immense amount of data, posing many challenging problems such as data storage, computational efficiency, and the so called "curse of dimensionality". Feature extraction and feature selection are the two main approaches for dimensionality reduction. Feature extraction techniques are used for reducing the dimensionality of the hyperspectral data by applying transforms on hyperspectral data. Feature selection techniques retain the physical meaning of the data by selecting a set of bands from the input hyperspectral dataset, which mainly contain the information needed for spectral unmixing. Although feature selection techniques are well-known for their dimensionality reduction potentials they are rarely used in the unmixing process. The majority of the existing state-of-the-art dimensionality reduction methods set criteria to the spectral information, which is derived by the whole wavelength, in order to define the optimum spectral subspace. These criteria are not associated with any particular application but with the data statistics, such as correlation and entropy values. However, each application is associated with specific land c over materials, whose spectral characteristics present variations in specific wavelengths. In forestry for example, many applications focus on tree leaves, in which specific pigments such as chlorophyll, xanthophyll, etc. determine the wavelengths where tree species, diseases, etc., can be detected. For such applications, when the unmixing process is applied, the tree species, diseases, etc., are considered as the endmembers of interest. This paper focuses on investigating the effects of band selection on the endmember extraction by exploiting the information of the vegetation absorbance spectral zones. More precisely, it is explored whether endmember extraction can be optimized when specific sets of initial bands related to leaf spectral characteristics are selected. Experiments comprise application of well-known signal subspace estimation and endmember extraction methods on a hyperspectral imagery that presents a forest area. Evaluation of the extracted endmembers showed that more forest species can be extracted as endmembers using selected bands.

Eggshell membrane-based biotemplating of mixed hemimicelle/admicelle as a solid-phase extraction adsorbent for carcinogenic polycyclic aromatic hydrocarbons.

PubMed

Wang, Weidong; Chen, Bo; Huang, Yuming

2014-08-13

A new solid-phase extraction (SPE) format was demonstrated, based on eggshell membrane (ESM) templating of the mixed hemimicelle/admicelle of linear alkylbenzenesulfonates (LAS) as an adsorbent for the enrichment of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in environmental aqueous samples. The LAS mixed hemimicelle/admicelle formation and SPE of the target PAHs were conducted simultaneously by adding the organic target and LAS through a column filled with 500 mg of ESM. The effect of various factors, including LAS concentration, solution pH, ionic strength, and humic acid concentration on the recoveries of PAHs were investigated and optimized. The results showed that LAS concentration and solution pH had obvious effect on extraction of PAHs, and the recoveries of PAHs compounds decreased in the presence of salt and humic acid. Under the optimized analytical conditions, the present method could respond down to 0.1-8.6 ng/L PAHs with a linear calibration ranging from 0.02 to 10 μg/L, showing a good PAHs enrichment ability with high sensitivity. The developed method was used satisfactorily for the detection of PAHs in environmental water samples. The mixed hemimicelle/admicelle adsorbent exhibited high extraction efficiency to PAHs and good selectivity with respect to natural organic matter and was advantageous over commercial C₁₈ adsorbent, for example, high extraction yield, high breakthrough volume, and easy regeneration.

Quercetin-imprinted chromatographic sorbents revisited: optimization of synthesis and rebinding protocols for application to natural resources.

PubMed

Pardo, Antonelle; Mespouille, Laetitia; Blankert, Bertrand; Trouillas, Patrick; Surin, Mathieu; Dubois, Philippe; Duez, Pierre

2014-10-17

Molecularly imprinted polymers (MIPs) based on quercetin and synthesized by either bulk, precipitation or suspension polymerization were characterized in terms of size and shape by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After a study of rebinding protocols, the optimal materials were evaluated as sorbents for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) to confirm the presence of imprinted cavities and to assess their selectivity. Besides quercetin, other structurally related natural compounds, naringenin, daidzein and curcumin, were employed for selectivity tests of MIPs. Although rebinding protocols previously described for such MIPs are typically based on binding, washing and eluting methanol-based solutions, we show that this highly polar solvent leads to weak specific interactions (imprinting factor<1) and poor sorbent properties, most probably because of hydrogen-bonding interferences between the MIP and MeOH. Similar experiments performed in tetrahydrofuran yield to much more improved properties (imprinting factor>2.4). This calls for reviewing most of previously published data on quercetin-MIPs; in proper binding conditions, published MIPs may prove more performing than initially assessed. As expected, tested MIPs exhibited the highest selective rebinding towards quercetin template (imprinting effect, quercetin, 3.41; naringenin, 1.54; daidzein, 1.38; curcumin, 1.67); the differences in selectivity between quercetin analogues were explained by the ligand geometries and H-bonding patterns obtained from quantum-chemical calculations. The evaluation of MIPs under identical analytical conditions allowed investigating the effect of the production method on chromatographic performances. The MIPs in bead materials (for quercetin, peak width, 0.69; number of theoretical plates, 143; symmetry factor, 2.22) provided a significant improvement in chromatographic efficiency over the bulk materials (for quercetin, peak width, 1.25; number of theoretical plates, 115; symmetry factor, 2.92). Using the quercetin-beaded MIP as SPE sorbent, quercetin was selectively extracted from Allium cepa L. extract. The MIP developed in this work therefore appears highly promising for the enrichment and determination of quercetin in natural products. Copyright © 2014 Elsevier B.V. All rights reserved.

Selection on worker honeybee responses to queen pheromone (Apis mellifera L.)

NASA Astrophysics Data System (ADS)

Pankiw, T.; Winston, Mark L.; Fondrk, M. Kim; Slessor, Keith N.

Disruptive selection for responsiveness to queen mandibular gland pheromone (QMP) in the retinue bioassay resulted in the production of high and low QMP responding strains of honeybees (Apis mellifera L.). Strains differed significantly in their retinue response to QMP after one generation of selection. By the third generation the high strain was on average at least nine times more responsive than the low strain. The strains showed seasonal phenotypic plasticity such that both strains were more responsive to the pheromone in the spring than in the fall. Directional selection for low seasonal variation indicated that phenotypic plasticity was an additional genetic component to retinue response to QMP. Selection for high and low retinue responsiveness to QMP was not an artifact of the synthetic blend because both strains were equally responsive or non-responsive to whole mandibular gland extracts compared with QMP. The use of these strains clearly pointed to an extra-mandibular source of retinue pheromones (Pankiw et al. 1995; Slessor et al. 1998; Keeling et al. 1999).

Wavelet Packet Feature Assessment for High-Density Myoelectric Pattern Recognition and Channel Selection toward Stroke Rehabilitation.

PubMed

Wang, Dongqing; Zhang, Xu; Gao, Xiaoping; Chen, Xiang; Zhou, Ping

2016-01-01

This study presents wavelet packet feature assessment of neural control information in paretic upper limb muscles of stroke survivors for myoelectric pattern recognition, taking advantage of high-resolution time-frequency representations of surface electromyogram (EMG) signals. On this basis, a novel channel selection method was developed by combining the Fisher's class separability index and the sequential feedforward selection analyses, in order to determine a small number of appropriate EMG channels from original high-density EMG electrode array. The advantages of the wavelet packet features and the channel selection analyses were further illustrated by comparing with previous conventional approaches, in terms of classification performance when identifying 20 functional arm/hand movements implemented by 12 stroke survivors. This study offers a practical approach including paretic EMG feature extraction and channel selection that enables active myoelectric control of multiple degrees of freedom with paretic muscles. All these efforts will facilitate upper limb dexterity restoration and improved stroke rehabilitation.

Employee Choice of a High-Deductible Health Plan across Multiple Employers

PubMed Central

Lave, Judith R; Men, Aiju; Day, Brian T; Wang, Wei; Zhang, Yuting

2011-01-01

Objective To determine factors associated with selecting a high-deductible health plan (HDHP) rather than a preferred provider plan (PPO) and to examine switching and market segmentation after initial selection. Data Sources/Study Setting Claims and benefit information for 2005–2007 from nine employers in western Pennsylvania first offering HDHP in 2006. Study Design We examined plan growth over time, used logistic regression to determine factors associated with choosing an HDHP, and examined the distribution of healthy and sick members across plan types. Data Extraction We linked employees with their dependents to determine family-level variables. We extracted risk scores, covered charges, employee age, and employee gender from claims data. We determined census-level race, education, and income information. Principal Findings Health status, gender, race, and education influenced the type of individual and family policies chosen. In the second year the HDHP was offered, few employees changed plans. Risk segmentation between HDHPs and PPOs existed, but it did not increase. Conclusions When given a choice, those who are healthier are more likely to select an HDHP leading to risk segmentation. Risk segmentation did not increase in the second year that HDHPs were offered. PMID:20849558

Characterization by high-performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry of the lipid fraction of Spirulina platensis pressurized ethanol extract.

PubMed

Herrero, Miguel; Vicente, María J; Cifuentes, Alejandro; Ibáñez, Elena

2007-01-01

Microalgae have been suggested as a potential source for new functional ingredients, making possible the development of new functional foods from natural origin. Among the natural ingredients, polyunsaturated fatty acids (PUFAs) have generally been identified as an interesting group of compounds with biological activity, mainly related to their anti-inflammatory properties. In this regard, the use of environmentally friendly extraction procedures (e.g. pressurized liquid extraction, PLE) to obtain such natural ingredients is also becoming necessary. In this work, an exhaustive characterization of the lipid fraction of a pressurized ethanolic extract of the microalga Spirulina platensis is carried out. To achieve this objective high-performance liquid chromatography (HPLC) coupled to quadrupole time-of-flight mass spectrometry (QTOF-MS) is employed. The use of the QTOF analyzer allows the selection and isolation of precursor ions as well as providing the high efficiency, sensitivity and mass accuracy required. By means of this powerful hyphenated technique, it was possible to identify several polar lipids in an extract of S. platensis (some of them, to our knowledge, described for the first time in this work), including four free fatty acids, four monogalactosyl monoacylglycerols, three phosphatidylglycerols and two sulfoquinovosyl diacylglycerols.

Extraction of nucleic acids from yeast cells and plant tissues using ethanol as medium for sample preservation and cell disruption.

PubMed

Linke, Bettina; Schröder, Kersten; Arter, Juliane; Gasperazzo, Tatiana; Woehlecke, Holger; Ehwald, Rudolf

2010-09-01

Here we report that dehydrated ethanol is an excellent medium for both in situ preservation of nucleic acids and cell disruption of plant and yeast cells. Cell disruption was strongly facilitated by prior dehydration of the ethanol using dehydrated zeolite. Following removal of ethanol, nucleic acids were extracted from the homogenate pellet using denaturing buffers. The method provided DNA and RNA of high yield and integrity. Whereas cell wall disruption was essential for extraction of DNA and large RNA molecules, smaller molecules such as tRNAs could be selectively extracted from undisrupted, ethanol-treated yeast cells. Our results demonstrate the utility of absolute ethanol for sample fixation, cell membrane and cell wall disruption, as well as preservation of nucleic acids during sample storage.

Simultaneous isolation of high-quality DNA, RNA, miRNA and proteins from tissues for genomic applications

PubMed Central

Peña-Llopis, Samuel; Brugarolas, James

2014-01-01

Genomic technologies have revolutionized our understanding of complex Mendelian diseases and cancer. Solid tumors present several challenges for genomic analyses, such as tumor heterogeneity and tumor contamination with surrounding stroma and infiltrating lymphocytes. We developed a protocol to (i) select tissues of high cellular purity on the basis of histological analyses of immediately flanking sections and (ii) simultaneously extract genomic DNA (gDNA), messenger RNA (mRNA), noncoding RNA (ncRNA; enriched in microRNA (miRNA)) and protein from the same tissues. After tissue selection, about 12–16 extractions of DNA/RNA/protein can be obtained per day. Compared with other similar approaches, this fast and reliable methodology allowed us to identify mutations in tumors with remarkable sensitivity and to perform integrative analyses of whole-genome and exome data sets, DNA copy numbers (by single-nucleotide polymorphism (SNP) arrays), gene expression data (by transcriptome profiling and quantitative PCR (qPCR)) and protein levels (by western blotting and immunohistochemical analysis) from the same samples. Although we focused on renal cell carcinoma, this protocol may be adapted with minor changes to any human or animal tissue to obtain high-quality and high-yield nucleic acids and proteins. PMID:24136348

Method for efficient recovery of high-purity polycarbonates from electronic waste.

PubMed

Weeden, George S; Soepriatna, Nicholas H; Wang, Nien-Hwa Linda

2015-02-17

More than one million tons of polycarbonates from waste electrical and electronic equipment are consigned to landfills at an increasing rate of 3-5% per year. Recycling the polymer waste should have a major environmental impact. Pure solvents cannot be used to selectively extract polycarbonates from mixtures of polymers with similar properties. In this study, selective mixed solvents are found using guidelines from Hansen solubility parameters, gradient polymer elution chromatography, and solubility tests. A room-temperature sequential extraction process using two mixed solvents is developed to recover polycarbonates with high yield (>95%) and a similar purity and molecular weight distribution as virgin polycarbonates. The estimated cost of recovery is less than 30% of the cost of producing virgin polycarbonates from petroleum. This method would potentially reduce raw materials from petroleum, use 84% less energy, reduce emission by 1-6 tons of CO2 per ton of polycarbonates, and reduce polymer accumulation in landfills and associated environmental hazards.

Recovery of high purity precious metals from printed circuit boards.

PubMed

Park, Young Jun; Fray, Derek J

2009-05-30

Waste printed circuit boards (WPCB) have an inherent value because of the precious metal content. For an effective recycling of WPCB, it is essential to recover the precious metals. This paper reports a promising method to recover the precious metals. Aqua regia was used as a leachant and the ratio between metals and leachant was fixed at 1/20 (g/ml). Silver is relatively stable so the amount of about 98 wt.% of the input was recovered without an additional treatment. Palladium formed a red precipitate during dissolution, which were consisted of Pd(NH(4))(2)Cl(6). The amount precipitated was 93 wt.% of the input palladium. A liquid-liquid extraction with toluene was used to extract gold selectively. Also, dodecanethiol and sodium borohydride solution were added to make gold nanoparticles. Gold of about 97 wt.% of the input was recovered as nanoparticles which was identified with a high-resolution transmission electron microscopy through selected area electron diffraction and nearest-neighbor lattice spacing.

Synthesis of molecular imprinting polymers for extraction of gallic acid from urine.

PubMed

Bhawani, Showkat Ahmad; Sen, Tham Soon; Ibrahim, Mohammad Nasir Mohammad

2018-02-21

The molecularly imprinted polymers for gallic acid were synthesized by precipitation polymerization. During the process of synthesis a non-covalent approach was used for the interaction of template and monomer. In the polymerization process, gallic acid was used as a template, acrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker and 2,2'-azobisisobutyronitrile as an initiator and acetonitrile as a solvent. The synthesized imprinted and non-imprinted polymer particles were characterized by using Fourier-transform infrared spectroscopy and scanning electron microscopy. The rebinding efficiency of synthesized polymer particles was evaluated by batch binding assay. The highly selective imprinted polymer for gallic acid was MIPI1 with a composition (molar ratio) of 1:4:20, template: monomer: cross-linker, respectively. The MIPI1 showed highest binding efficiency (79.50%) as compared to other imprinted and non-imprinted polymers. The highly selective imprinted polymers have successfully extracted about 80% of gallic acid from spiked urine sample.

Whole-body tissue stabilization and selective extractions via tissue-hydrogel hybrids for high-resolution intact circuit mapping and phenotyping.

PubMed

Treweek, Jennifer B; Chan, Ken Y; Flytzanis, Nicholas C; Yang, Bin; Deverman, Benjamin E; Greenbaum, Alon; Lignell, Antti; Xiao, Cheng; Cai, Long; Ladinsky, Mark S; Bjorkman, Pamela J; Fowlkes, Charless C; Gradinaru, Viviana

2015-11-01

To facilitate fine-scale phenotyping of whole specimens, we describe here a set of tissue fixation-embedding, detergent-clearing and staining protocols that can be used to transform excised organs and whole organisms into optically transparent samples within 1-2 weeks without compromising their cellular architecture or endogenous fluorescence. PACT (passive CLARITY technique) and PARS (perfusion-assisted agent release in situ) use tissue-hydrogel hybrids to stabilize tissue biomolecules during selective lipid extraction, resulting in enhanced clearing efficiency and sample integrity. Furthermore, the macromolecule permeability of PACT- and PARS-processed tissue hybrids supports the diffusion of immunolabels throughout intact tissue, whereas RIMS (refractive index matching solution) grants high-resolution imaging at depth by further reducing light scattering in cleared and uncleared samples alike. These methods are adaptable to difficult-to-image tissues, such as bone (PACT-deCAL), and to magnified single-cell visualization (ePACT). Together, these protocols and solutions enable phenotyping of subcellular components and tracing cellular connectivity in intact biological networks.

Comparison of methods for the extraction of DNA from formalin-fixed, paraffin-embedded archival tissues.

PubMed

Sengüven, Burcu; Baris, Emre; Oygur, Tulin; Berktas, Mehmet

2014-01-01

Discussing a protocol involving xylene-ethanol deparaffinization on slides followed by a kit-based extraction that allows for the extraction of high quality DNA from FFPE tissues. DNA was extracted from the FFPE tissues of 16 randomly selected blocks. Methods involving deparaffinization on slides or tubes, enzyme digestion overnight or for 72 hours and isolation using phenol chloroform method or a silica-based commercial kit were compared in terms of yields, concentrations and the amplifiability. The highest yield of DNA was produced from the samples that were deparaffinized on slides, digested for 72 hours and isolated with a commercial kit. Samples isolated with the phenol-chloroform method produced DNA of lower purity than the samples that were purified with kit. The samples isolated with the commercial kit resulted in better PCR amplification. Silica-based commercial kits and deparaffinized on slides should be considered for DNA extraction from FFPE.

Evaluation of antimicrobial activity of selected plant extracts by rapid XTT colorimetry and bacterial enumeration.

PubMed

Al-Bakri, Amal G; Afifi, Fatma U

2007-01-01

The aim of this study was to screen and evaluate the antimicrobial activity of indigenous Jordanian plant extracts, dissolved in dimethylsulfoxide, using the rapid XTT assay and viable count methods. XTT rapid assay was used for the initial screening of antimicrobial activity for the plant extracts. Antimicrobial activity of potentially active plant extracts was further assessed using the "viable plate count" method. Four degrees of antimicrobial activity (high, moderate, weak and inactive) against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, respectively, were recorded. The plant extracts of Hypericum triquetrifolium, Ballota undulata, Ruta chalepensis, Ononis natrix, Paronychia argentea and Marrubium vulgare had shown promising antimicrobial activity. This study showed that while both XTT and viable count methods are comparable when estimating the overall antimicrobial activity of experimental substances, there is no strong linear correlation between the two methods.

Characterization of the key aroma compounds in beef extract using aroma extract dilution analysis.

PubMed

Takakura, Yukiko; Sakamoto, Tomohiro; Hirai, Sachi; Masuzawa, Takuya; Wakabayashi, Hidehiko; Nishimura, Toshihide

2014-05-01

Aroma extract dilution analysis (AEDA) of an ether extract prepared from beef extract (BE) and subsequent identification experiments led to the determination of seven aroma-active compounds in the flavor dilution (FD) factor range of 32-128. Omission experiments to select the most aroma-active compounds from the seven aroma compounds suggested that 2,3,5-trimethyl pyrazine, 1-octen-3-ol, 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were the main active compounds contributing to the aroma of BE. Aroma recombination, addition, and omission experiments of the four aroma compounds in taste-reconstituted BE showed that each compound had an individual aroma profile. A comparison of the overall aroma between this recombination mixture and BE showed a high similarity, suggesting that the key aroma compounds had been identified successfully. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of agronomic variables on the composition of mate tea leaves (Ilex paraguariensis) extracts obtained from CO2 extraction at 30 degrees C and 175 bar.

PubMed

Esmelindro, Angela Aquino; Girardi, Jonathan Dos Santos; Mossi, Altemir; Jacques, Rosângela Assis; Dariva, Cláudio

2004-04-07

The aim of this work is to assess the influence of light intensity (plants with direct sun exposure and in a controlled light intensity) and age of leaves (6-24 months) on the characteristics of the extracts of mate tea leaves obtained from carbon dioxide at high pressures. Samples of mate were collected in an experiment conducted under agronomic control at Industria e Comercio de Erva-Mate Barão LTDA, Brazil. The content of selected organic compounds of the extracts was evaluated by gas chromatography together with mass spectrometry. Quantitative analysis of caffeine, theobromine, phytol, vitamin E, squalene, and stigmasterol was performed, and the results showed that field variables exert a strong influence on the liquid yield and on the chemical distribution of the extracts.

Fabric phase sorptive extraction followed by UHPLC-MS/MS for the analysis of benzotriazole UV stabilizers in sewage samples.

PubMed

Montesdeoca-Esponda, Sarah; Sosa-Ferrera, Zoraida; Kabir, Abuzar; Furton, Kenneth G; Santana-Rodríguez, José Juan

2015-10-01

A fast and sensitive sample preparation strategy using fabric phase sorptive extraction followed by ultra-high-performance liquid chromatography and tandem mass spectrometry detection has been developed to analyse benzotriazole UV stabilizer compounds in aqueous samples. Benzotriazole UV stabilizer compounds are a group of compounds added to sunscreens and other personal care products which may present detrimental effects to aquatic ecosystems. Fabric phase sorptive extraction is a novel solvent minimized sample preparation approach that integrates the advantages of sol-gel derived hybrid inorganic-organic nanocomposite sorbents and the flexible, permeable and hydrophobic surface chemistry of polyester fabric. It is a highly sensitive, fast, efficient and inexpensive device that can be reused and does not suffer from coating damage, unlike SPME fibres or stir bars. In this paper, we optimized the extraction of seven benzotriazole UV filters evaluating the majority of the parameters involved in the extraction process, such as sorbent chemistry selection, extraction time, back-extraction solvent, back-extraction time and the impact of ionic strength. Under the optimized conditions, fabric phase sorptive extraction allows enrichment factors of 10 times with detection limits ranging from 6.01 to 60.7 ng L(-1) and intra- and inter-day % RSDs lower than 11 and 30 % for all compounds, respectively. The optimized sample preparation technique followed by ultra-high-performance liquid chromatography and tandem mass spectrometry detection was applied to determine the target analytes in sewage samples from wastewater treatment plants with different purification processes of Gran Canaria Island (Spain). Two UV stabilizer compounds were measured in ranges 17.0-60.5 ng mL(-1) (UV 328) and 69.3-99.2 ng mL(-1) (UV 360) in the three sewage water samples analysed.

Platform construction and extraction mechanism study of magnetic mixed hemimicelles solid-phase extraction

PubMed Central

Xiao, Deli; Zhang, Chan; He, Jia; Zeng, Rong; Chen, Rong; He, Hua

2016-01-01

Simple, accurate and high-throughput pretreatment method would facilitate large-scale studies of trace analysis in complex samples. Magnetic mixed hemimicelles solid-phase extraction has the power to become a key pretreatment method in biological, environmental and clinical research. However, lacking of experimental predictability and unsharpness of extraction mechanism limit the development of this promising method. Herein, this work tries to establish theoretical-based experimental designs for extraction of trace analytes from complex samples using magnetic mixed hemimicelles solid-phase extraction. We selected three categories and six sub-types of compounds for systematic comparative study of extraction mechanism, and comprehensively illustrated the roles of different force (hydrophobic interaction, π-π stacking interactions, hydrogen-bonding interaction, electrostatic interaction) for the first time. What’s more, the application guidelines for supporting materials, surfactants and sample matrix were also summarized. The extraction mechanism and platform established in the study render its future promising for foreseeable and efficient pretreatment under theoretical based experimental design for trace analytes from environmental, biological and clinical samples. PMID:27924944

Reversibility of radiocaesium sorption on illite

NASA Astrophysics Data System (ADS)

de Koning, Arjan; Comans, Rob N. J.

2004-07-01

Adsorption of trace amounts of radiocaesium on NH 4-, K-, and Na-saturated Fithian illite and subsequent desorption by 1 M NH 4 showed that a substantial amount of radiocaesium (44%, 46%, and 91% for NH 4-, K-, and Na-illite, respectively) cannot be desorbed after only 5 min of adsorption. Our results suggest that this instantaneous fixation is caused by the collapse of the frayed edges of the clay mineral and the relatively high concentration of radiocaesium building up in solution in the batch desorption experiments. Consequently, commonly applied high-NH 4 extractions underestimate truly exchangeable amounts of radiocaesium in soils and sediments containing illitic clay minerals. The rate of desorption of trace amounts of radiocaesium from the solids using high NH 4 or Cs concentrations has a half-life of about 2 yr, reflecting radiocaesium desorption from (partially) collapsed interlayers. Extraction of radiocaesium from illite after 5 min of contact time with a Cs-selective adsorbent or a 1 × 10 -6 M CsCl solution shows that 100% of the bound radiocaesium is readily available. The desorption rate in the presence of a Cs-selective adsorbent has a half-life of about 0.2 yr. Desorption of radiocaesium from illite using different ammonium concentrations shows that radiocaesium partitioning follows reversible ion-exchange theory if the NH 4 concentration is below 1 × 10 -4 M, and sufficient time (weeks) is allowed for the reaction to proceed. Thus, radiocaesium sorption reversibility in the natural environment is much higher than generally assumed, and equilibrium solid/liquid partitioning may be assumed for the long-term modelling of radiocaesium mobility in the natural environment. In the particular case of anoxic freshwater sediments with very high NH 4 concentrations in the pore waters (up to several mmol.L -1), collapse of the frayed edges of illite may occur, influencing radiocaesium partitioning. If collapse occurs before radiocaesium adsorbs to illite, high caesium sorption reversibility as measured by high-NH 4 extraction can be expected because further collapse of the frayed edges during the extraction procedure will be limited. This effect has indeed been observed earlier in the extraction of radiocaesium from anoxic freshwater sediments with high-NH 4 solutions and was as yet unexplained.

Kruskal-Wallis-based computationally efficient feature selection for face recognition.

PubMed

Ali Khan, Sajid; Hussain, Ayyaz; Basit, Abdul; Akram, Sheeraz

2014-01-01

Face recognition in today's technological world, and face recognition applications attain much more importance. Most of the existing work used frontal face images to classify face image. However these techniques fail when applied on real world face images. The proposed technique effectively extracts the prominent facial features. Most of the features are redundant and do not contribute to representing face. In order to eliminate those redundant features, computationally efficient algorithm is used to select the more discriminative face features. Extracted features are then passed to classification step. In the classification step, different classifiers are ensemble to enhance the recognition accuracy rate as single classifier is unable to achieve the high accuracy. Experiments are performed on standard face database images and results are compared with existing techniques.

Ionic liquids: solvents and sorbents in sample preparation.

PubMed

Clark, Kevin D; Emaus, Miranda N; Varona, Marcelino; Bowers, Ashley N; Anderson, Jared L

2018-01-01

The applications of ionic liquids (ILs) and IL-derived sorbents are rapidly expanding. By careful selection of the cation and anion components, the physicochemical properties of ILs can be altered to meet the requirements of specific applications. Reports of IL solvents possessing high selectivity for specific analytes are numerous and continue to motivate the development of new IL-based sample preparation methods that are faster, more selective, and environmentally benign compared to conventional organic solvents. The advantages of ILs have also been exploited in solid/polymer formats in which ordinarily nonspecific sorbents are functionalized with IL moieties in order to impart selectivity for an analyte or analyte class. Furthermore, new ILs that incorporate a paramagnetic component into the IL structure, known as magnetic ionic liquids (MILs), have emerged as useful solvents for bioanalytical applications. In this rapidly changing field, this Review focuses on the applications of ILs and IL-based sorbents in sample preparation with a special emphasis on liquid phase extraction techniques using ILs and MILs, IL-based solid-phase extraction, ILs in mass spectrometry, and biological applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Production and New Extraction Method of Polyketide Red Pigments Produced by Ascomycetous Fungi from Terrestrial and Marine Habitats

PubMed Central

Lebeau, Juliana; Venkatachalam, Mekala; Fouillaud, Mireille; Petit, Thomas; Vinale, Francesco; Dufossé, Laurent; Caro, Yanis

2017-01-01

The use of ascomycetous fungi as pigment producers opens the way to an alternative to synthetic dyes, especially in the red-dye industries, which have very few natural pigment alternatives. The present paper aimed to bio-prospect and screen out 15 selected ascomycetous fungal strains, originating from terrestrial and marine habitats belonging to seven different genera (Penicillium, Talaromyces, Fusarium, Aspergillus, Trichoderma, Dreschlera, and Paecilomyces). We identified four strains, Penicillium purpurogenum rubisclerotium, Fusarium oxysporum, marine strains identified as Talaromyces spp., and Trichoderma atroviride, as potential red pigment producers. The extraction of the pigments is a crucial step, whereby the qualitative and quantitative compositions of each fungal extract need to be respected for reliable identification, as well as preserving bioactivity. Furthermore, there is a growing demand for more sustainable and cost-effective extraction methods. Therefore, a pressurized liquid extraction technique was carried out in this study, allowing a greener and faster extraction step of the pigments, while preserving their chemical structures and bioactivities in comparison to conventional extraction processes. The protocol was illustrated with the production of pigment extracts from P. purpurogenum rubisclerotium and Talaromyces spp. Extracts were analyzed by high-performance liquid-chromatography combined with photodiode array-detection (HPLC-DAD) and high-resolution mass spectrometry (UHPLC-HRMS). The more promising strain was the isolate Talaromyces spp. of marine origin. The main polyketide pigment produced by this strain has been characterized as N-threoninerubropunctamine, a non-toxic red Monascus-like azaphilone pigment. PMID:29371552

Focused microwave-assisted extraction combined with solid-phase microextraction and gas chromatography-mass spectrometry for the selective analysis of cocaine from coca leaves.

PubMed

Bieri, Stefan; Ilias, Yara; Bicchi, Carlo; Veuthey, Jean-Luc; Christen, Philippe

2006-04-21

An effective combination of focused microwave-assisted extraction (FMAE) with solid-phase microextraction (SPME) prior to gas chromatography (GC) is described for the selective extraction and quantitative analysis of cocaine from coca leaves (Erythroxylum coca). This approach required switching from an organic extraction solvent to an aqueous medium more compatible with SPME liquid sampling. SPME was performed in the direct immersion mode with a universal 100 microm polydimethylsiloxane (PDMS) coated fibre. Parameters influencing this extraction step, such as solution pH, sampling time and temperature are discussed. Furthermore, the overall extraction process takes into account the stability of cocaine in alkaline aqueous solutions at different temperatures. Cocaine degradation rate was determined by capillary electrophoresis using the short end injection procedure. In the selected extraction conditions, less than 5% of cocaine was degraded after 60 min. From a qualitative point of view, a significant gain in selectivity was obtained with the incorporation of SPME in the extraction procedure. As a consequence of SPME clean-up, shorter columns could be used and analysis time was reduced to 6 min compared to 35 min with conventional GC. Quantitative results led to a cocaine content of 0.70 +/- 0.04% in dry leaves (RSD <5%) which agreed with previous investigations.

Characterization of the aroma profile of novel Brazilian wines by solid-phase microextraction using polymeric ionic liquid sorbent coatings.

PubMed

Crucello, Juliana; Miron, Luiz F O; Ferreira, Victor H C; Nan, He; Marques, Marcia O M; Ritschel, Patricia S; Zanus, Mauro C; Anderson, Jared L; Poppi, Ronei J; Hantao, Leandro W

2018-05-28

In this study, a series of polymeric ionic liquid (PIL) sorbent coatings is evaluated for the extraction of polar volatile organic compounds (VOCs) from Brazilian wines using headspace solid-phase microextraction (HS-SPME), including samples from 'Isabella' and 'BRS Magna' cultivars-the latter was recently introduced by the Brazilian Agricultural Research Corporation - National Grape & Wine Research Center. The structurally tuned SPME coatings were compared to the commercial SPME phases, namely poly(acrylate) (PA) and divinylbenzene/carboxen/poly(dimethylsiloxane) (DVB/CAR/PDMS). The separation, detection and identification of the aroma profiles were obtained using comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). The best performing PIL-based SPME fiber, namely 1-hexadecyl-3-vinylimidazolium bis[(trifluoromethyl)sulfonyl]imide with 1,12-di(3-vinylimidazolium)dodecane dibis[(trifluoromethyl)sulfonyl]imide incorporated cross-linker supported on an elastic nitinol wire, exhibited superior performance to DVB/CAR/PDMS regarding the average number of extracted peaks and extracted more polar analytes providing additional insight into the aroma profile of 'BRS Magna' wines. Four batches of wine were evaluated, namely 'Isabella' and 'BRS Magna' vintages 2015 and 2016, using highly selective PIL-based SPME coatings and enabled the detection of 350+ peaks. Furthermore, this is the first report evaluating the aroma of 'BRS Magna' wines. A hybrid approach that combined pixel-based Fisher ratio and peak table-based data comparison was used for data handling. This proof-of-concept experiment provided reliable and statistically valid distinction of wines that may guide regulation agencies to create high sample throughput protocols to screen wines exported by Brazilian vintners. Graphical abstract Highly selective extraction of wine aroma using polymeric ionic liquid.

Integrating Dimension Reduction and Out-of-Sample Extension in Automated Classification of Ex Vivo Human Patellar Cartilage on Phase Contrast X-Ray Computed Tomography

PubMed Central

Nagarajan, Mahesh B.; Coan, Paola; Huber, Markus B.; Diemoz, Paul C.; Wismüller, Axel

2015-01-01

Phase contrast X-ray computed tomography (PCI-CT) has been demonstrated as a novel imaging technique that can visualize human cartilage with high spatial resolution and soft tissue contrast. Different textural approaches have been previously investigated for characterizing chondrocyte organization on PCI-CT to enable classification of healthy and osteoarthritic cartilage. However, the large size of feature sets extracted in such studies motivates an investigation into algorithmic feature reduction for computing efficient feature representations without compromising their discriminatory power. For this purpose, geometrical feature sets derived from the scaling index method (SIM) were extracted from 1392 volumes of interest (VOI) annotated on PCI-CT images of ex vivo human patellar cartilage specimens. The extracted feature sets were subject to linear and non-linear dimension reduction techniques as well as feature selection based on evaluation of mutual information criteria. The reduced feature set was subsequently used in a machine learning task with support vector regression to classify VOIs as healthy or osteoarthritic; classification performance was evaluated using the area under the receiver-operating characteristic (ROC) curve (AUC). Our results show that the classification performance achieved by 9-D SIM-derived geometric feature sets (AUC: 0.96 ± 0.02) can be maintained with 2-D representations computed from both dimension reduction and feature selection (AUC values as high as 0.97 ± 0.02). Thus, such feature reduction techniques can offer a high degree of compaction to large feature sets extracted from PCI-CT images while maintaining their ability to characterize the underlying chondrocyte patterns. PMID:25710875

Highly selective stir bar coated with dummy molecularly imprinted polymers for trace analysis of bisphenol A in milk.

PubMed

Zhan, Wen; Wei, Fangdi; Xu, Guanhong; Cai, Zheng; Du, Shuhu; Zhou, Xuemin; Li, Fei; Hu, Qin

2012-04-01

A water compatible molecularly imprinted polymers (MIPs) coated stir bar for bisphenol A(BPA) was prepared with 3,3',5,5'-tetrabromobisphenol A as the dummy template molecule in this study. The dummy molecularly imprinted polymers coated stir bar (DMIPs-SB) showed better selectivity than the bars coated with polydimethylsiloxane or non-imprinted polymers when used to extract BPA and its three analogues. The saturated adsorption amount of the DMIPs coating was 3.0 times over that of the non-imprinted polymers coating. To achieve the optimum extraction performance, several parameters, including extraction and desorption time, pH value, adsorption temperature and stirring speed were investigated. The high-performance liquid chromatography combined with the DMIPs-SB was employed in the analysis of BPA in aqueous solution. The linear range of BPA concentration in aqueous medium was 0.0228-2.28 ng/mL with correlation coefficient of 0.9994 and the detection limit was about 6.84 × 10(-3) ng/mL based on three times ratio of signal to noise. This method was directly applied to the determination of trace BPA in milk with satisfactory results. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of novel molecularly imprinted solid-phase microextraction fiber and its application for the determination of triazines in complicated samples coupled with high-performance liquid chromatography.

PubMed

Hu, Xiaogang; Hu, Yuling; Li, Gongke

2007-04-13

A novel molecularly imprinted polymer (MIP) coated solid-phase microextraction (SPME) fiber that could be coupled directly to high-performance liquid chromatography (HPLC) was prepared with prometryn as the template molecule. The characteristics and application of this fiber were investigated. Electron microscope photographs indicated that the MIP coating with average thickness of 25.0 microm was homogeneous and porous. The extraction yield of prometryn with the MIP-coated fibers was 10 times as much as that with the non-imprinted polymer (NIP) coated fibers. And special selectivity to other triazines which have similar structure to prometryn was discovered with the MIP-coated fibers. A method for the determination of triazines by the MIP-coated SPME coupled with HPLC was developed. The optimized extraction conditions were studied. Detection limits for the triazines studied were within the range of 0.012-0.090 microg/L. The method was applied to five triazines determination in the spiked soybean, corn, lettuce, and soil samples with the recoveries of 78.0-103.5%, 82.4-113.4%, 75.5-83.4%, and 81.0-106.1%, respectively. The MIP-coated fibers are suitable for the selective extraction of trace triazines in complicated samples.

A new efficient method for color image compression based on visual attention mechanism

NASA Astrophysics Data System (ADS)

Shao, Xiaoguang; Gao, Kun; Lv, Lily; Ni, Guoqiang

2010-11-01

One of the key procedures in color image compression is to extract its region of interests (ROIs) and evaluate different compression ratios. A new non-uniform color image compression algorithm with high efficiency is proposed in this paper by using a biology-motivated selective attention model for the effective extraction of ROIs in natural images. When the ROIs have been extracted and labeled in the image, the subsequent work is to encode the ROIs and other regions with different compression ratios via popular JPEG algorithm. Furthermore, experiment results and quantitative and qualitative analysis in the paper show perfect performance when comparing with other traditional color image compression approaches.

Dispersive admicelle solid-phase extraction based on sodium dodecyl sulfate coated Fe3 O4 nanoparticles for the selective adsorption of three alkaloids in Gegen-Qinlian oral liquid before high-performance liquid chromatography.

PubMed

Shi, Zhihong; Xu, Dan; Zhao, Xuan; Li, Xinghong; Shen, Huimin; Yang, Bing; Zhang, Hongyi

2017-12-01

A novel dispersive admicelle solid-phase extraction method based on sodium dodecyl sulfate-coated Fe 3 O 4 nanoparticles was developed for the selective adsorption of berberine, coptisine, and palmatine in Gegen-Qinlian oral liquid before high-performance liquid chromatography. Fe 3 O 4 nanoparticles were synthesized by a chemical coprecipitation method and characterized by using transmission electron microscopy. Under acidic conditions, the surface of Fe 3 O 4 nanoparticles was coated with sodium dodecyl sulfate to form a nano-sized admicelle magnetic sorbent. Owing to electrostatic interaction, the alkaloids were adsorbed onto the oppositely charged admicelle magnetic nanoparticles. The quick separation of the analyte-adsorbed nanoparticles from the sample solution was performed by using Nd-Fe-B magnet. Best extraction efficiency was achieved under the following conditions: 800 μL Fe 3 O 4 nanoparticles suspension (20 mg/mL), 150 μL sodium dodecyl sulfate solution (10 mg/mL), pH 2, and vortexing time 2 min for the extraction of alkaloids from 10 mL of diluted sample. Four hundred microliters of methanol was used to desorb the alkaloids by vortexing for 1 min. Satisfactory extraction recoveries were obtained in the range of 85.9-120.3%, relative standard deviations for intra- and interday precisions were less than 6.3 and 10.0%, respectively. Finally, the established method was successfully applied to analyze the alkaloids in two batches of Gegen-Qinlian oral liquids. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spectral characterization of a pteridine derivative from cyanide-utilizing bacterium Bacillus subtilis - JN989651.

PubMed

Durairaju Nisshanthini, S; Teresa Infanta S, Antony K; Raja, Duraisamy Senthil; Natarajan, Karuppannan; Palaniswamy, M; Angayarkanni, Jayaraman

2015-04-01

Soil and water samples were collected from various regions of SIPCOT and nearby Vanappadi Lake, Ranipet, Tamilnadu, India. Based on their colony morphology and their stability during subculturing, 72 bacteria were isolated, of which 14 isolates were actinomycetes. Preliminary selection was carried out to exploit the ability of the microorganisms to utilize sodium cyanate as nitrogen source. Those organisms that were able to utilize cyanate were subjected to secondary screening viz., utilization of sodium cyanide as the nitrogen source. The oxygenolytic cleavage of cyanide is dependent on cyanide monooxygenase which obligately requires pterin cofactor for its activity. Based on this, the organisms capable of utilizing sodium cyanide were tested for the presence of pterin. Thin layer chromatography (TLC) of the cell extracts using n-butanol: 5 N glacial acetic acid (4:1) revealed that 10 out of 12 organisms that were able to utilize cyanide had the pterin-related blue fluorescent compound in the cell extract. The cell extracts of these 10 organisms were subjected to high performance thin layer chromatography (HPTLC) for further confirmation using a pterin standard. Based on the incubation period, cell biomass yield, peak height and area, strain VPW3 was selected and was identified as Bacillus subtilis. The Rf value of the cell extract was 0.73 which was consistent with the 0.74 Rf value of the pterin standard when scanned at 254 nm. The compound was extracted and purified by preparative High Performance Liquid Chromatography (HPLC). Characterization of the compound was performed by ultraviolet spectrum, fluorescence spectrum, Electrospray Ionization-Mass Spectrometry (ESI-MS), and Nuclear Magnetic Resonance spectroscopy (NMR). The compound is proposed to be 6-propionyl pterin (2-amino-6-propionyl-3H-pteridin-4-one).

A novel extracellular glycosidase activity from Rhodotorula mucilaginosa: its application potential in wine aroma enhancement.

PubMed

Hu, K; Zhu, X L; Mu, H; Ma, Y; Ullah, N; Tao, Y S

2016-02-01

The aim of the work was to evaluate the application potential of a glycosidase extract of one indigenous non-Saccharomyces strain in wine aroma enhancement. The isolate was selected from a local winemaking region in China for its high β-glucosidase level and was identified as Rhodotorula mucilaginosa. The tolerance of the glycosidase extract to the typical winemaking conditions was assessed using the activity of its β-glucosidase. After that, the hydrolysis capacity of R. mucilaginosa glycosidase for liberation of grape aroma glycosides was characterized in comparison to commercial enzyme preparations. Results of this work revealed that glycosidase extract from R. mucilaginosa proved to be active in the presence of 0-20% (w/v) glucose, 0-20% (v/v) ethanol and at pH 3·0-5·0. In the hydrolysis of aroma precursors, enzymes obtained from different origins possessed various levels of specificity and activity, showing high origin dependence (α = 0·05). Compared to commercial enzymes, the indigenous R. mucilaginosa glycosidase extract presented better catalytic preference for the 'fruity and floral' glycosides of benzenic compounds and C13 -norisoprenoids, but less sensitivity to the glycosides of C6 compounds and volatile phenols. This work presents a novel extracellular glycosidase preparation from an indigenous Rhodotorula mucilaginosa strain selected from a local winemaking region in China. This enzyme extract exhibits strong tolerance towards winemaking conditions. It shows hydrolysis specificity for glycosides of benzenic compounds and C13 -norisoprenoids, proving a potential candidate for improving floral and fruity aroma characteristics of wine. © 2015 The Society for Applied Microbiology.

Antimicrobial, antiplasmodial, haemolytic and antioxidant activities of crude extracts from three selected Togolese medicinal plants.

PubMed

Karou, Simplice D; Tchacondo, Tchadjobo; Ouattara, Lassina; Anani, Kokou; Savadogo, Aly; Agbonon, Amegnona; Attaia, Mossaclok Ben; de Souza, Comlan; Sakly, Mohsen; Simpore, Jacques

2011-10-01

To investigate the antioxidant, antimicrobial, antiplasmodial, acute toxicity and haemolytic activities of methanolic extracts of three plants. Phytochemical analysis to determine the phenolic contents was also carried out. The 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free radical scavenging, NCCLS broth microdilution and Plasmodium Lactate Dehydrogenase (pLDH) assays were used to determine antioxidant, antimicrobial and antiplasmodial activities, respectively. Haemolysis assay was conducted on A(+) human red blood cells and acute toxicity on male Swiss albino mice. Phenolics were quantitatively determined using spectrophotometric methods. The DPPH assay yielded interesting antioxidant activities of methanolic extract of Parinari curatellifolia (P. curatellifolia) and Entada africana (E. africana) (IC(50) were 0.20±0.01 μg/mL and 0.47±0.01 μg/mL, respectively). This activity was highly correlated with phenolic contents of extracts. The antimicrobial tests displayed minimal inhibitory concentrations (MICs) values ranging from 0.90 to 1.80 mg/mL for Serratia marcescens (S. marcescens) the most susceptible bacterial strain. MIC value was 1.20 mg/mL for susceptible fungal strains including Mucor rouxi (M. rouxi), Fusarium oxyporum (F. oxyporum) and Rhizopus nigricans (R. nigricans). pLDH assay showed moderate antiplasmodial activity of Balanites aegyptiaca (B. aegyptiaca) (IC(50) = 24.56±3.45 μg/mL), however this extract was highly haemolytic and toxic in mice (LD(50) = 625±128 mg/kg). Our results support in part the use of the selected plants in the treatment of microbial infections. In addition the plant showed interesting antioxidant activity that could be useful in the management of oxidative stress. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Phenolic composition, antioxidant capacity and antibacterial activity of selected Irish Brassica vegetables.

PubMed

Jaiswal, Amit Kumar; Rajauria, Gaurav; Abu-Ghannam, Nissreen; Gupta, Shilpi

2011-09-01

Vegetables belonging to the Brassicaceae family are rich in polyphenols, flavonoids and glucosinolates, and their hydrolysis products, which may have antibacterial, antioxidant and anticancer properties. In the present study, phenolic composition, antibacterial activity and antioxidant capacity of selected Brassica vegetables, including York cabbage, Brussels sprouts, broccoli and white cabbage were evaluated after extraction with aqueous methanol. Results obtained showed that York cabbage extract had the highest total phenolic content, which was 33.5, followed by 23.6, 20.4 and 18.4 mg GAE/g of dried weight (dw) of the extracts for broccoli, Brussels sprouts and white cabbage, respectively. All the vegetable extracts had high flavonoid contents in the order of 21.7, 17.5, 15.4 and 8.75 mg QE/g of extract (dw) for York cabbage, broccoli, Brussels sprouts and white cabbage, respectively. HPLC-DAD analysis showed that different vegetables contain a mixture of distinct groups of phenolic compounds. All the extracts studied showed a rapid and concentration dependent antioxidant capacity in diverse antioxidant systems. The antibacterial activity was determined against Gram-positive and Gram-negative bacteria. York cabbage extract exhibited significantly higher antibacterial activity against Listeria monocytogenes (100%) and Salmonella abony (94.3%), being the most susceptible at a concentration of 2.8%, whereas broccoli, Brussels sprouts and white cabbage had moderate to weak activity against all the test organisms. Good correlation (r2 0.97) was found between total phenolic content obtained by spectrophotometric analysis and the sum of the individual polyphenols monitored by HPLC-DAD.

Identification of HSP70-inducing activity in Arnica montana extract and purification and characterization of HSP70-inducers.

PubMed

Usui, Keiko; Ikeda, Tsuyoshi; Horibe, Yuumi; Nakao, Mitsuyoshi; Hoshino, Tatsuya; Mizushima, Tohru

2015-04-01

The expression of heat shock proteins (HSPs), particularly HSP70, is receiving considerable attention in the field of cosmetics, particularly given our recent report that ultraviolet-induced melanin production, skin damage and wrinkle formation were all suppressed in transgenic mice expressing HSP70. In the present study, we searched for HSP70-inducers from a library of herbal extracts that have already been approved as quasi-pharmaceutical products in Japan. We selected an ethanol extract of Arnica montana (A. montana), based on its high HSP70-inducing activity and low cytotoxicity. Cell viability was determined by MTT method and expression of HPS70 was monitored by immunoblotting analysis. From the extract, we purified and identified eight sesquiterpene lactones (AM1-8) as HSP70-inducers, among which AM-2 (helenalin 2-methylbutyrate) was selected due to its good HSP70-inducing properties and low cytotoxicity. Treatment of cultured mouse melanoma cells with AM-2 or A. montana extract up-regulated the expression of HSP70 in a dose-dependent manner. This treatment also activated heat shock factor-1, a transcription factor for hsp genes. Furthermore, pre-treatment of cells with AM-2 or A. montana extract decreased melanin production and expression and activity of tyrosinase. These results suggest that AM-2 and A. montana extract could be beneficial for use in hypopigmenting cosmetics as a consequence of their stimulatory effects on HSP70 expression. Copyright © 2015 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Text feature extraction based on deep learning: a review.

PubMed

Liang, Hong; Sun, Xiao; Sun, Yunlei; Gao, Yuan

2017-01-01

Selection of text feature item is a basic and important matter for text mining and information retrieval. Traditional methods of feature extraction require handcrafted features. To hand-design, an effective feature is a lengthy process, but aiming at new applications, deep learning enables to acquire new effective feature representation from training data. As a new feature extraction method, deep learning has made achievements in text mining. The major difference between deep learning and conventional methods is that deep learning automatically learns features from big data, instead of adopting handcrafted features, which mainly depends on priori knowledge of designers and is highly impossible to take the advantage of big data. Deep learning can automatically learn feature representation from big data, including millions of parameters. This thesis outlines the common methods used in text feature extraction first, and then expands frequently used deep learning methods in text feature extraction and its applications, and forecasts the application of deep learning in feature extraction.

Extraction of saponifiable lipids from wet microalgal biomass for biodiesel production.

PubMed

Jiménez Callejón, María J; Robles Medina, Alfonso; Macías Sánchez, María D; Hita Peña, Estrella; Esteban Cerdán, Luis; González Moreno, Pedro A; Molina Grima, Emilio

2014-10-01

Saponifiable lipids (SLs) were extracted with hexane from wet biomass (86 wt% water) of the microalga Nannochloropsis gaditana in order to transform them into fatty acid methyl esters (FAMEs, biodiesel). The influence of homogenization pressure on SL extraction yield at low temperature (20-22 °C) was studied. Homogenization at 1700 bar tripled the SL extraction yield. Two biomass batches with similar total lipid content but different lipidic compositions were used. Batch 1 contained fewer SLs (12.0 wt%) and neutral saponifiable lipids (NSLs, 7.9 wt%) than batch 2 (21.6 and 17.2 wt%, respectively). For this reason, and due to the selectivity of hexane toward NSLs, high SL yield (69.1 wt%) and purity (71.0 wt%) were obtained from batch 2. Moreover, this extract contains a small percentage of polyunsaturated fatty acids (16.9 wt%), thereby improving the biodiesel quality. Finally, up to 97.0% of extracted SLs were transformed to FAMEs by acid catalyzed transesterification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ion extraction capabilities of two-grid accelerator systems. [for spacecraft propulsion

NASA Technical Reports Server (NTRS)

Rovang, D. C.; Wilbur, P. J.

1984-01-01

An experimental investigation into the ion extraction capabilities of two-grid accelerator systems common to electrostatic ion thrusters is described. A large body of experimental data which facilitates the selection of the accelerator system geometries and operating parameters necessary to maximize the extracted ion current is presented. Results suggest that the impingement-limited perveance is not dramatically affected by reductions in screen hole diameter to 0.5 mm. Impingement-limited performance is shown to depend most strongly on grid separation distance, accelerator hole diameter ratio, the discharge-to-total accelerating voltage ratio, and the net-to-total accelerating voltage ratio. Results obtained at small grid separation ratios suggest a new grid operating condition where high beam current per hole levels are achieved at a specified net accelerating voltage. It is shown that this operating condition is realized at an optimum ratio of net-to-total accelerating voltage ratio which is typically quite high.

The TRUSPEAK Concept: Combining CMPO and HDEHP for Separating Trivalent Lanthanides from the Transuranic Elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lumetta, Gregg J.; Gelis, Artem V.; Braley, Jenifer C.

2013-04-08

Combining octyl(phenyl)-N,N-diisobutyl-carbamoylmethyl-phosphine oxide (CMPO) and bis-(2-ethylhexyl) phosphoric acid (HDEHP) into a single process solvent for separating transuranic elements from liquid high-level waste is explored. Co-extraction of americium and the lanthanide elements from nitric acid solution is possible with a solvent mixture consisting of 0.1-M CMPO plus 1-M HDEHP in n-dodecane. Switching the aqueous-phase chemistry to a citrate-buffered solution of diethylene triamine pentaacetic acid (DTPA) allows for selective stripping of americium, separating it from the lanthanide elements. Potential strategies for managing molybdenum and zirconium (both of which co-extract with americium and the lanthanides) have been developed. The work presented here demonstratesmore » the feasibility of combining CMPO and HDEHP into a single extraction solvent for recovering americium from high-level waste and its separation from the lanthanides.« less

Employment of High-Performance Thin-Layer Chromatography for the Quantification of Oleuropein in Olive Leaves and the Selection of a Suitable Solvent System for Its Isolation with Centrifugal Partition Chromatography.

PubMed

Boka, Vasiliki-Ioanna; Argyropoulou, Aikaterini; Gikas, Evangelos; Angelis, Apostolis; Aligiannis, Nektarios; Skaltsounis, Alexios-Leandros

2015-11-01

A high-performance thin-layer chromatographic methodology was developed and validated for the isolation and quantitative determination of oleuropein in two extracts of Olea europaea leaves. OLE_A was a crude acetone extract, while OLE_AA was its defatted residue. Initially, high-performance thin-layer chromatography was employed for the purification process of oleuropein with fast centrifugal partition chromatography, replacing high-performance liquid-chromatography, in the stage of the determination of the distribution coefficient and the retention volume. A densitometric method was developed for the determination of the distribution coefficients, KC = CS/CM. The total concentrations of the target compound in the stationary phase (CS) and in the mobile phase (CM) were calculated by the area measured in the high-performance thin-layer chromatogram. The estimated Kc was also used for the calculation of the retention volume, VR, with a chromatographic retention equation. The obtained data were successfully applied for the purification of oleuropein and the experimental results confirmed the theoretical predictions, indicating that high-performance thin-layer chromatography could be an important counterpart in the phytochemical study of natural products. The isolated oleuropein (purity > 95%) was subsequently used for the estimation of its content in each extract with a simple, sensitive and accurate high-performance thin-layer chromatography method. The best fit calibration curve from 1.0 µg/track to 6.0 µg/track of oleuropein was polynomial and the quantification was achieved by UV detection at λ 240 nm. The method was validated giving rise to an efficient and high-throughput procedure, with the relative standard deviation % of repeatability and intermediate precision not exceeding 4.9% and accuracy between 92% and 98% (recovery rates). Moreover, the method was validated for robustness, limit of quantitation, and limit of detection. The amount of oleuropein for OLE_A, OLE_AA, and an aqueous extract of olive leaves was estimated to be 35.5% ± 2.7, 51.5% ± 1.4, and 12.5% ± 0.12, respectively. Statistical analysis proved that the method is repeatable and selective, and can be effectively applied for the estimation of oleuropein in olive leaves' extracts, and could potentially replace high-performance liquid chromatography methodologies developed so far. Thus, the phytochemical investigation of oleuropein could be based on high-performance thin-layer chromatography coupled with separation processes, such as fast centrifugal partition chromatography, showing efficacy and credibility. Georg Thieme Verlag KG Stuttgart · New York.

"Bligh and Dyer" and Folch Methods for Solid-Liquid-Liquid Extraction of Lipids from Microorganisms. Comprehension of Solvatation Mechanisms and towards Substitution with Alternative Solvents.

PubMed

Breil, Cassandra; Abert Vian, Maryline; Zemb, Thomas; Kunz, Werner; Chemat, Farid

2017-03-27

Bligh and Dyer (B & D) or Folch procedures for the extraction and separation of lipids from microorganisms and biological tissues using chloroform/methanol/water have been used tens of thousands of times and are "gold standards" for the analysis of extracted lipids. Based on the Conductor-like Screening MOdel for realistic Solvatation (COSMO-RS), we select ethanol and ethyl acetate as being potentially suitable for the substitution of methanol and chloroform. We confirm this by performing solid-liquid extraction of yeast ( Yarrowia lipolytica IFP29 ) and subsequent liquid-liquid partition-the two steps of routine extraction. For this purpose, we consider similar points in the ternary phase diagrams of water/methanol/chloroform and water/ethanol/ethyl acetate, both in the monophasic mixtures and in the liquid-liquid miscibility gap. Based on high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes, and gas chromatography coupled with a flame ionisation detector (GC/FID) to obtain fatty acid profiles, this greener solvents pair is found to be almost as effective as the classic methanol-chloroform couple in terms of efficiency and selectivity of lipids and non-lipid material. Moreover, using these bio-sourced solvents as an alternative system is shown to be as effective as the classical system in terms of the yield of lipids extracted from microorganism tissues, independently of their apparent hydrophilicity.

“Bligh and Dyer” and Folch Methods for Solid–Liquid–Liquid Extraction of Lipids from Microorganisms. Comprehension of Solvatation Mechanisms and towards Substitution with Alternative Solvents

PubMed Central

Breil, Cassandra; Abert Vian, Maryline; Zemb, Thomas; Kunz, Werner; Chemat, Farid

2017-01-01

Bligh and Dyer (B & D) or Folch procedures for the extraction and separation of lipids from microorganisms and biological tissues using chloroform/methanol/water have been used tens of thousands of times and are “gold standards” for the analysis of extracted lipids. Based on the Conductor-like Screening MOdel for realistic Solvatation (COSMO-RS), we select ethanol and ethyl acetate as being potentially suitable for the substitution of methanol and chloroform. We confirm this by performing solid–liquid extraction of yeast (Yarrowia lipolytica IFP29) and subsequent liquid–liquid partition—the two steps of routine extraction. For this purpose, we consider similar points in the ternary phase diagrams of water/methanol/chloroform and water/ethanol/ethyl acetate, both in the monophasic mixtures and in the liquid–liquid miscibility gap. Based on high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes, and gas chromatography coupled with a flame ionisation detector (GC/FID) to obtain fatty acid profiles, this greener solvents pair is found to be almost as effective as the classic methanol–chloroform couple in terms of efficiency and selectivity of lipids and non-lipid material. Moreover, using these bio-sourced solvents as an alternative system is shown to be as effective as the classical system in terms of the yield of lipids extracted from microorganism tissues, independently of their apparent hydrophilicity. PMID:28346372

Mining natural variation for maize improvement: Selection on phenotypes and genes

USDA-ARS?s Scientific Manuscript database

Maize is highly genetically and phenotypically diverse. Tropical maize and teosinte are important genetic resources that harbor unique alleles not found in temperate maize hybrids. To access these resources, breeders must be able to extract favorable unique alleles from tropical maize and teosinte f...

Selective leaching of Zn from spent alkaline batteries using environmentally friendly approaches.

PubMed

Maryam Sadeghi, S; Vanpeteghem, Guillaumme; Neto, Isabel F F; Soares, Helena M V M

2017-02-01

The main aim of this work was to evaluate the possibility of using microwave or ultrasound to assist the efficient and selective leaching of Zn from spent alkaline batteries and compare the results with those obtained using the conventional method. Two different strategies were applied: acid leaching of a washed residue and alkaline leaching of the original residue. In both (acid and alkaline) approaches, the use of microwave- or ultrasound-assisted leaching increased the extraction of Zn compared with the best results obtained using conventional leaching [acid leaching (1.5mol/L H 2 SO 4 , 3h, 80°C), 90% of Zn extracted; alkaline leaching (6mol/L NaOH, 3h, 80°C), 42% of Zn extracted]. With acid leaching, 94% of the Zn was extracted using microwave-assisted leaching (1 cycle, 30s, 1mol/L H 2 SO 4 ), and 92% of the Zn was extracted using ultrasound-assisted leaching (2min, 0.1p, 20% amplitude, 1mol/L H 2 SO 4 ). Ultrasound-assisted leaching resulted in a more selective (Zn/Mn ratio of 5.1) Zn extraction than microwave-assisted leaching (Zn/Mn ratio of 3.5); both processes generated a concentrated Zn solution (⩾18.7g/L) with a purity (83.3% and 77.7%, respectively) that was suitable for electrowinning. With alkaline leaching, microwave- (1 cycle, 3 min, 4mol/L NaOH) and ultrasound-assisted (14min, 0.1p, 20% amplitude, 4mol/L NaOH) leaching extracted about 80% of the Zn and less than 0.01% of the Mn, which resulted in lesser concentrated Zn solutions (approximately 16.5g/L) but with high purity (>99.5%) that was suitable for the recovery of Zn by precipitation. The microwave- and ultrasound-assisted leaching strategies used in this work proved to be efficient and environmentally-friendly approaches for the extraction of Zn from spent alkaline residues since a concentrated Zn solution with adequate purity for subsequent Zn recovery was obtained using significantly decreased leaching times and concentrations of chemicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Carrier mediated hollow fiber liquid phase microextraction combined with HPLC-UV for preconcentration and determination of some tetracycline antibiotics.

PubMed

Shariati, Shahab; Yamini, Yadollah; Esrafili, Ali

2009-02-01

In the present study, a simple and efficient preconcentration method was developed using carrier mediated three phase liquid phase microextraction prior to HPLC-UV for simultaneous extraction and determination of trace amounts of highly hydrophilic tetracycline antibiotics including tetracycline (TCN), oxytetracycline (OTCN) and doxycycline (DCN) in bovine milk, human plasma and water samples. For extraction, 11.0 mL of the aqueous sample containing TCNs and 0.05 M Na(2)HPO(4) (9.10.995). Finally, applicability of the proposed method was successfully confirmed by extraction and determination of the drugs in water and plasma samples as well as in bovine milk samples with low and high fat contents. Comparing to the traditional methods, the proposed method exhibits high sensitivity and high preconcentration factors as well as good precision. The extraction setup is simple and due to active transport of analytes, high cleanup effect and good selectivity are obtained in extraction process.

Extraction of methylxanthines from guaraná seeds, maté leaves, and cocoa beans using supercritical carbon dioxide and ethanol.

PubMed

Saldaña, Marleny D A; Zetzl, Carsten; Mohamed, Rahoma S; Brunner, G

2002-08-14

New experimental data on the extraction of caffeine from guaraná seeds and maté tea leaves, and theobromine from cocoa beans, with supercritical CO2 were obtained using a high-pressure extraction apparatus. The effect of the addition of ethanol to carbon dioxide on the extraction efficiency was also investigated. Caffeine extraction yields of 98% of the initial caffeine content in both wet ground guaraná seeds and maté tea leaves were obtained. Extractions of caffeine from guaraná seeds and maté tea leaves also exhibited a retrograde behavior for the two temperatures considered in this work. In the removal of theobromine from cocoa beans, a much smaller extraction yield was obtained with longer extraction periods and consequently larger solvent requirements. The results of this study confirm the higher selectivity of CO2 for caffeine in comparison with that for theobromine, and also the influence of other components in each particular natural product on the extraction of methylxanthines. The effect of the addition of ethanol to carbon dioxide on the extraction of methylxanthines was significant, particularly in the extraction of theobromine from cocoa beans. In general, the use of ethanol results in lower solvent and energy requirements and thereby improved extraction efficiency.

Quantification of polychlorinated dibenzo-p-dioxins and dibenzofurans by direct injection of sample extract into the comprehensive multidimensional gas chromatograph/high-resolution time-of-flight mass spectrometer.

PubMed

Shunji, Hashimoto; Yoshikatsu, Takazawa; Akihiro, Fushimi; Hiroyasu, Ito; Kiyoshi, Tanabe; Yasuyuki, Shibata; Masa-aki, Ubukata; Akihiko, Kusai; Kazuo, Tanaka; Hideyuki, Otsuka; Katsunori, Anezaki

2008-01-18

Polychlorinated dibenzo-p-dioxins and dibenzofurans in crude extracts of fly ash and flue gas from municipal waste incinerators were quantified using a comprehensive multidimensional gas chromatograph (GC x GC) coupled to a high-resolution time-of-flight mass spectrometer (HR-TOFMS). For identification and quantification, we developed our own program to prepare 3D chromatograms of selected mass numbers from the data of the GC x GC/HR-TOFMS. Isolation of all congeners with a TCDD toxic equivalency factor from the other isomers by only one injection was confirmed. The instrumental detection limit of TCDD on the GC x GC/HR-TOFMS was 0.9 pg by the relative calibration method. Quantification of these substances in the crude extracts was achieved by direct injection to the GC x GC/HR-TOFMS. The results agree with the values obtained using a generic gas chromatography/high-resolution mass spectrometry (GC/HRMS) system. It was confirmed that measurement by high-resolution TOFMS and GC x GC effectively reduces interference from other chemicals.

Anti-plasmodial activity of Dicoma tomentosa (Asteraceae) and identification of urospermal A-15-O-acetate as the main active compound

PubMed Central

2012-01-01

Background Natural products could play an important role in the challenge to discover new anti-malarial drugs. In a previous study, Dicoma tomentosa (Asteraceae) was selected for its promising anti-plasmodial activity after a preliminary screening of several plants traditionally used in Burkina Faso to treat malaria. The aim of the present study was to further investigate the anti-plasmodial properties of this plant and to isolate the active anti-plasmodial compounds. Methods Eight crude extracts obtained from D. tomentosa whole plant were tested in vitro against two Plasmodium falciparum strains (3D7 and W2) using the p-LDH assay (colorimetric method). The Peters’ four-days suppressive test model (Plasmodium berghei-infected mice) was used to evaluate the in vivo anti-plasmodial activity. An in vitro bioguided fractionation was undertaken on a dichloromethane extract, using preparative HPLC and TLC techniques. The identity of the pure compound was assessed using UV, MS and NMR spectroscopic analysis. In vitro cytotoxicity against WI38 human fibroblasts (WST-1 assay) and haemolytic activity were also evaluated for extracts and pure compounds in order to check selectivity. Results The best in vitro anti-plasmodial results were obtained with the dichloromethane, diethylether, ethylacetate and methanol extracts, which exhibited a high activity (IC50 ≤ 5 μg/ml). Hot water and hydroethanolic extracts also showed a good activity (IC50 ≤ 15 μg/ml), which confirmed the traditional use and the promising anti-malarial potential of the plant. The activity was also confirmed in vivo for all tested extracts. However, most of the active extracts also exhibited cytotoxic activity, but no extract was found to display any haemolytic activity. The bioguided fractionation process allowed to isolate and identify a sesquiterpene lactone (urospermal A-15-O-acetate) as the major anti-plasmodial compound of the plant (IC50 < 1 μg/ml against both 3D7 and W2 strains). This was also found to be the main cytotoxic compound (SI = 3.3). While this melampolide has already been described in the plant, this paper is the first report on the biological properties of this compound. Conclusions The present study highlighted the very promising anti-plasmodial activity of D. tomentosa and enabled to identify its main active compound, urospermal A-15-O-acetate. The high anti-plasmodial activity of this compound merits further study about its anti-plasmodial mechanism of action. The active extracts of D. tomentosa, as well as urospermal A 15-O-acetate, displayed only a moderate selectivity, and further studies are needed to assess the safety of the use of the plant by the local population. PMID:22909422

[The determination of molecular sulphur in Matsesta mineral water and its analog Novonukutskaya mineral water].

PubMed

Khutorianskiĭ, V A; Smirnov, A I; Matveev, D A

2014-01-01

The method of microcolumn reversed phase high performance liquid chromatography (rp-HPLC) was employed to determine the content of elemental sulphur in mineral waters. The study envisaged the analysis of the samples of sulphide-containing mineral waters Novonukutskaya and Matsesta obtained by the solid phase extraction technique. Based on these data, the authors discuss the origin and the circulation of sulphur in the hydrogen sulphide sources. The elution conditions selected in this study ensured the high-resolution separation of the octasulphur peak from the peaks of allotropic components of the extract whereas the two-wave detection technique allowed to identify the peaks of molecular sulphur.

Hollow porous ionic liquids composite polymers based solid phase extraction coupled online with high performance liquid chromatography for selective analysis of hydrophilic hydroxybenzoic acids from complex samples.

PubMed

Dai, Xingping; Wang, Dongsheng; Li, Hui; Chen, Yanyi; Gong, Zhicheng; Xiang, Haiyan; Shi, Shuyun; Chen, Xiaoqing

2017-02-10

Polar and hydrophilic properties of hydroxybenzoic acids usually made them coelute with interferences in high performance liquid chromatography (HPLC) analysis. Then selective analysis of them was necessary. Herein, hollow porous ionic liquids composite polymers (PILs) based solid phase extraction (SPE) was firstly fabricated and coupled online with HPLC for selective analysis of hydroxybenzoic acids from complex matrices. Hollow porous PILs were firstly synthesized using Mobil Composition of Matter No. 48 (MCM-48) spheres as sacrificial support, 1-vinyl-3-methylimidazolium chloride (VMIM + Cl - ) as monomer, and ethylene glycol dimethacrylate (EGDMA) as cross-linker. Various parameters affecting synthesis, adsorption and desorption behaviors were investigated and optimized. Steady-state adsorption studies showed the resulting hollow porous PILs exhibited high adsorption capacity, fast adsorption kinetics, and excellent specific adsorption. Subsequently, the application of online SPE system was studied by selective analysis of protocatechuic acid (PCA), 4-hydroxybenzoic acid (4-HBA), and vanillic acid (VA) from Pollen Typha angustifolia. The obtained limit of detection (LOD) varied from 0.002 to 0.01μg/mL, the linear range (0.05-5.0μg/mL) was wide with correlation coefficient (R) from 0.9982 to 0.9994, and the average recoveries at three spiking levels ranged from 82.7 to 102.4%, with column-to-column relative standard deviation (RSD) below 8.1%. The proposed online method showed good accuracy, precision, specificity and convenience, which opened up a universal and efficient route for selective analysis of hydroxybenzoic acids from complex samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of sulfonylurea herbicides in water and food samples using sol-gel glass-based immunoaffinity extraction and liquid chromatography-ultraviolet/diode array detection or liquid chromatography-tandem mass spectrometry.

PubMed

Degelmann, Petra; Egger, Sebastian; Jürling, Heinrich; Müller, Josef; Niessner, Reinhard; Knopp, Dietmar

2006-03-22

Immunoaffinity supports (IAS) were prepared using broad specific polyclonal anti-sulfonylurea (SU) antibodies immobilized in sol-gel glass. Two different kinds of supports were applied, crushed sol-gel monoliths and sol-gel-coated highly porous silica particles. Both were used for the quantitative enrichment of SUs in natural water and food samples followed by high-performance liquid chromatography-ultraviolet/diode array detection (HPLC-UV/DAD) and tandem mass spectrometry (LC-MS/MS), respectively. Loading, washing, and elution conditions of IAS were optimized. The capacity of supports was determined for 30 SUs and compared with the cross-reactivity pattern of the direct competitive enzyme-linked immunosorbent assay. The capacities correlated well with the affinity to individual SU compounds. Even analytes to which the polyclonal antibodies showed only a lower cross-reactivity could be enriched to a certain degree, if a sufficient capacity of IAS was provided. The IAS could be reused at least 10 times without a loss of effectiveness. Recovery of 16 selected SUs extracted from spiked water and food samples was dependent on the affinity of both immobilized antibodies to single compounds and matrix interferences. In water, 13 SUs showed recoveries higher than 80% when immunoaffinity extraction was used in combination with LC-UV/DAD. On the basis of the enrichment of 200 mL of aqueous sample, corresponding limit of detection (LOD) values ranged between 20 and 100 ng/L. The recoveries of 10 SUs, which were extracted from 10 g of potato spiked at a 10 microg/kg level, were higher than 75%. For grain samples, recoveries were at the same order for at least five SU herbicides. The LOD of LC-MS/MS measurements was about 1 order of magnitude higher, i.e., gave LODs between 1.1 and 6.9 microg/kg of food sample, depending on the compound and extraction procedure. These LODs provide evidence that the main advantage of the prepared IAS is their high selectivity for group specific recognition of SUs as compared to other nonspecific solid phase extraction materials.

Rapid and automated analysis of aflatoxin M1 in milk and dairy products by online solid phase extraction coupled to ultra-high-pressure-liquid-chromatography tandem mass spectrometry.

PubMed

Campone, Luca; Piccinelli, Anna Lisa; Celano, Rita; Pagano, Imma; Russo, Mariateresa; Rastrelli, Luca

2016-01-08

This study reports a fast and automated analytical procedure for the analysis of aflatoxin M1 (AFM1) in milk and dairy products. The method is based on the simultaneous protein precipitation and AFM1 extraction, by salt-induced liquid-liquid extraction (SI-LLE), followed by an online solid-phase extraction (online SPE) coupled to ultra-high-pressure-liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis to the automatic pre-concentration, clean up and sensitive and selective determination of AFM1. The main parameters affecting the extraction efficiency and accuracy of the analytical method were studied in detail. In the optimal conditions, acetonitrile and NaCl were used as extraction/denaturant solvent and salting-out agent in SI-LLE, respectively. After centrifugation, the organic phase (acetonitrile) was diluted with water (1:9 v/v) and purified (1mL) by online C18 cartridge coupled with an UHPLC column. Finally, selected reaction monitoring (SRM) acquisition mode was applied to the detection of AFM1. Validation studies were carried out on different dairy products (whole and skimmed cow milk, yogurt, goat milk, and powder infant formula), providing method quantification limits about 25 times lower than AFM1 maximum levels permitted by EU regulation 1881/2006 in milk and dairy products for direct human consumption. Recoveries (86-102%) and repeatability (RSD<3, n=6) meet the performance criteria required by EU regulation N. 401/2006 for the determination of the levels of mycotoxins in foodstuffs. Moreover, no matrix effects were observed in the different milk and dairy products studied. The proposed method improves the performance of AFM1 analysis in milk samples as AFM1 determination is performed with a degree of accuracy higher than the conventional methods. Other advantages are the reduction of sample preparation procedure, time and cost of the analysis, enabling high sample throughput that meet the current concerns of food safety and the public health protection. Copyright © 2015 Elsevier B.V. All rights reserved.

Packed in-tube solid phase microextraction with graphene oxide supported on aminopropyl silica: Determination of target triazines in water samples.

PubMed

De Toffoli, Ana L; Fumes, Bruno H; Lanças, Fernando M

2018-02-22

On-line in-tube solid phase microextraction (in-tube SPME) coupled to high performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) was successfully applied to the determination of selected triazines in water samples. The method based on the employment of a packed column containing graphene oxide (GO) supported on aminopropyl silica (Si) showed that the extraction phase has a high potential for triazines extraction aiming to its physical-chemical properties including ultrahigh specific surface area, good mechanical and thermal stability and high fracture strength. Injection volume and loading time were both investigated and optimized. The method validation using Si-GO to extract and concentrate the analytes showed satisfactory results, good sensitivity, good linearity (0.2-4.0 µg L -1 ) and low detection limits (1.1-2.9 ng L -1 ). The high extraction efficiency was determined with enrichment factors ranging from 1.2-2.9 for the lowest level, 1.3-4.9 intermediate level and 1.2-3.0 highest level (n = 3). Although the analytes were not detected in the real samples evaluated, the method has demonstrated to be efficient through its application in the analysis of spiked triazines in ground and mineral water samples.

Preparation of molecularly imprinted solid-phase microextraction fiber for the selective removal and extraction of the antiviral drug abacavir in environmental and biological matrices.

PubMed

Terzopoulou, Zoi; Papageorgiou, Myrsini; Kyzas, George Z; Bikiaris, Dimitrios N; Lambropoulou, Dimitra A

2016-03-24

In the present study, a molecularly imprinted solid-phase microextraction fiber (MIP-SPMEf) was synthesized and applied for the selective removal and extraction of the antiviral drug, abacavir (ABA). Morphology and structure characterization of fibers were performed by scanning electron microscopy and Fourier transform infrared spectra, respectively. The effects on the adsorption behavior of the process parameters were studied and the equilibrium data were fitted by the Langmuir, Freundlich and Langmuir-Freundlich models. The maximum adsorption capability (Qmax) was determined by Langmuir- Freundlich model and was 149 mg/g for MIP-SPMEf. In the next step, SPME methodology followed by liquid desorption and liquid chromatography with mass spectrometry (LC/MS) has been developed and evaluated for the determination of the target compound in environmental and biological matrices (surface waters, wastewaters and urine). Parameters that could influence SPME efficiency were investigated. Then, optimization of stirring speed, extraction time and salt content was carried out by using a central composite design (CCD) and response surface methodology (RSM). A quadratic model between dependent and independent variables was built. Under the optimum conditions (extraction time 40 min, stirring rate 650 rpm and salt content 0.3% NaCl w/v) the validated method presented a high sensitivity and selectivity with LODs and LOQs in the range of 10.1-13.6 and 33.3-43.9 ng/L, respectively. The developed method was successfully applied to the analysis of ABA in real samples. The percentage extraction efficiency ranged from 88 to 99% revealing good accuracy and absence of matrix effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Antimicrobial agents from selected medicinal plants in Libya.

PubMed

Muhaisen, Hasan M H; Ab-Mous, Miftah Mailoud; Ddeeb, Fadel A; Rtemi, Aboclaid Ali; Taba, Omer M; Parveen, Mehtab

2016-03-01

To test the in vitro antimicrobial efficacy of water and methanol extracts of 23 plant species that are commonly used in Libyan folk medicine. The antimicrobial activity was determined using the well-diffusion method. Four test microorganisms were used namely, Escherichia coli, Salmonella species, Staphylococcus aureus and Bacillus subtilis. The minimum inhibitory concentration (MIC) was determined for the high biologically active crude plant extracts. Among 23 medicinal plants used in the study, only 5 methanolic extracts [Rosmarinus offcinalis L., Carduus marianium L., Lantana camara L., Rhus tripartite (ueria) Grande, and Thymus capitatus (L.) Hoffm (link)] showed the highest antimicrobial activity against Staphylococcus aureus, Bacillus subtilis and Salmonella species, while 22 methanolic and aqueous extracts showed moderate to weak antimicrobial activity on all tested organisms. However 19 of the extracts showed no activity at all against Gram-ve and Gram +ve microorganisms. MIC was found to be 1.25 mg/mL (Thymus capitatus), 3 mg/mL (Rhus tripartite), 4 mg/mL (Carduus marianium), 5 mg/mL (Rosamarinus officinalis) and 5 mg/mL (Lantana camara), respectively. The present results revealed that, crude methanolic extracts of the investigated Libyan folk medicinal plants exhibited mild to high in vitro antibacterial activities against Gram-positive and Gram-negative microorganisms.

Solid-phase extraction of galloyl- and caffeoylquinic acids from natural sources (Galphimia glauca and Arnicae flos) using pure zirconium silicate and bismuth citrate powders as sorbents inside micro spin columns.

PubMed

Hussain, Shah; Schönbichler, Stefan A; Güzel, Yüksel; Sonderegger, Harald; Abel, Gudrun; Rainer, Matthias; Huck, Christian W; Bonn, Günther K

2013-10-01

Galloyl- and caffeoylquinic acids are among the most important pharmacological active groups of natural compounds. This study describes a pre-step in isolation of some selected representatives of these groups from biological samples. A selective solid-phase extraction (SPE) method for these compounds may help assign classes and isomer designations within complex mixtures. Pure zirconium silicate and bismuth citrate powders (325 mesh) were employed as two new sorbents for optimized SPE of phenolic acids. These sorbents possess electrostatic interaction sites which accounts for additional interactions for carbon acid moieties as compared to hydrophilic and hydrophobic sorbents alone. Based on this principle, a selective SPE method for 1,3,4,5-tetragalloylquinic acid (an anti-HIV and anti-asthamatic agent) as a starting compound was developed and then deployed upon other phenolic acids with success. The recoveries and selectivities of both sorbents were compared to most commonly applied and commercially available sorbents by using high performance liquid chromatography. The nature of interaction between the carrier sorbent and the acidic target molecules was investigated by studying hydrophilic (silica), hydrophobic (C18), mixed-mode (ionic and hydrophobic: Oasis(®) MAX) and predominantly electrostatic (zirconium silicate) materials. The newly developed zirconium silicate and bismuth citrate stationary phases revealed promising results for the selective extraction of galloyl- and caffeoylquinic acids from natural sources. It was observed that zirconium silicate exhibited maximum recovery and selectivity for tetragalloylquinic acid (84%), chlorogenic acid (82%) and dicaffeoylquinic acid (94%) among all the tested sorbents. Copyright © 2013 Elsevier B.V. All rights reserved.

A new method based on supercritical fluid extraction for polyacetylenes and polyenes from Echinacea pallida (Nutt.) Nutt. roots.

PubMed

Tacchini, Massimo; Spagnoletti, Antonella; Brighenti, Virginia; Prencipe, Francesco Pio; Benvenuti, Stefania; Sacchetti, Gianni; Pellati, Federica

2017-11-30

The genus Echinacea (Asteraceae) includes species traditionally used in phytotherapy. Among them, Echinacea pallida (Nutt.) Nutt. root extracts are characterized by a representative antiproliferative activity, due to the presence of acetylenic compounds. In this study, supercritical fluid extraction (SFE) was applied and compared with conventional Soxhlet extraction (SE) in order to obtain a bioactive extract highly rich in polyacetylenes and polyenes from E. pallida roots. The composition of the extracts was monitored by means of HPLC-UV/DAD and HPLC-ESI-MS n by using an Ascentis Express C 18 column (150mm×3.0mm I.D., 2.7μm, Supelco, Bellefonte, PA, USA) with a mobile phase composed of (A) water and (B) acetonitrile, under gradient elution. By keeping SFE time at the threshold of 1h (15min static and 45min dynamic for 1 cycle) with the oven temperature set at 40-45°C and 90bar of pressure, an overall extraction yield of 1.18-1.21% (w/w) was obtained, with a high selectivity for not oxidized lipophilic compounds. The biological activity of the extracts was evaluated against human non-small lung A549 and breast carcinoma MCF-7 cancer cell lines. The cytotoxic effect of the SFE extract was more pronounced towards the MCF-7 than the A549 cancer cells, with IC 50 values ranging from 21.01±2.89 to 31.11±2.l4μg/mL; cell viability was affected mainly between 24 and 48h of exposure. The results show the possibility of a new "green" approach to obtain extracts highly rich in genuine polyacetylenes and polyenes from E. pallida roots. The bioactivity evaluation confirmed the cytotoxicity of E. pallida extracts against the considered cancer cell lines, especially against MCF-7 cells, thus suggesting to represent a valuable tool for applicative purposes in cancer prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantitative analysis of benzodiazepines in vitreous humor by high-performance liquid chromatography

PubMed Central

Bazmi, Elham; Behnoush, Behnam; Akhgari, Maryam; Bahmanabadi, Leila

2016-01-01

Objective: Benzodiazepines are frequently screened drugs in emergency toxicology, drugs of abuse testing, and in forensic cases. As the variations of benzodiazepines concentrations in biological samples during bleeding, postmortem changes, and redistribution could be biasing forensic medicine examinations, hence selecting a suitable sample and a validated accurate method is essential for the quantitative analysis of these main drug categories. The aim of this study was to develop a valid method for the determination of four benzodiazepines (flurazepam, lorazepam, alprazolam, and diazepam) in vitreous humor using liquid–liquid extraction and high-performance liquid chromatography. Methods: Sample preparation was carried out using liquid–liquid extraction with n-hexane: ethyl acetate and subsequent detection by high-performance liquid chromatography method coupled to diode array detector. This method was applied to quantify benzodiazepines in 21 authentic vitreous humor samples. Linear curve for each drug was obtained within the range of 30–3000 ng/mL with coefficient of correlation higher than 0.99. Results: The limit of detection and quantitation were 30 and 100 ng/mL respectively for four drugs. The method showed an appropriate intra- and inter-day precision (coefficient of variation < 10%). Benzodiazepines recoveries were estimated to be over 80%. The method showed high selectivity; no additional peak due to interfering substances in samples was observed. Conclusion: The present method was selective, sensitive, accurate, and precise for the quantitative analysis of benzodiazepines in vitreous humor samples in forensic toxicology laboratory. PMID:27635251

Aqueous two-phase based on ionic liquid liquid-liquid microextraction for simultaneous determination of five synthetic food colourants in different food samples by high-performance liquid chromatography.

PubMed

Sha, Ou; Zhu, Xiashi; Feng, Yanli; Ma, Weixing

2015-05-01

A rapid and effective method of aqueous two-phase systems based on ionic liquid microextraction for the simultaneous determination of five synthetic food colourants (tartrazine, sunset yellow, amaranth, ponceau 4R and brilliant blue) in food samples was established. High-performance liquid chromatography coupled with an ultraviolet detector of variable wavelength was used for the determinations. 1-alkyl-3-methylimidazolium bromide was selected as the extraction reagent. The extraction efficiency of the five colourants in the proposed system is influenced by the types of salts, concentrations of salt and [CnMIM]Br, as well as the extracting time. Under the optimal conditions, the extraction efficiencies for these five colourants were above 95%. The phase behaviours of aqueous two-phase system and extraction mechanism were investigated by UV-vis spectroscopy. This method was applied to the analysis of the five colourants in real food samples with the detection limit of 0.051-0.074 ng/mL. Good spiked recoveries from 93.2% to 98.9% were obtained. Copyright © 2014 Elsevier Ltd. All rights reserved.

Graphene oxide: an adsorbent for the extraction and quantification of aflatoxins in peanuts by high-performance liquid chromatography.

PubMed

Yu, Li; Li, Peiwu; Zhang, Qi; Zhang, Wen; Ding, Xiaoxia; Wang, Xiupin

2013-11-29

In this paper, graphene oxide (GO) was synthesized and specifically selected by centrifugation to extract four aflatoxins (B1, B2, G1, and G2) as an effective adsorbent. Then, the amount of aflatoxins was quantitatively measured by high-performance liquid chromatography (HPLC). The GO was characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), and ultraviolet (UV) spectrophotometer. Several parameters that could affect the extraction efficiency, including the GO amount, methanol concentration in the extraction solvent, spiked amount, extraction time, and elution cycle, were also investigated and optimized in this work. Under optimal conditions, good linear relationships were achieved with the correlation coefficient (r) ranging from 0.99217 to 0.99995. The detection limit of this method for the four aflatoxins ranged from 0.08 to 0.65ng/g. Finally, the proposed method has been successfully applied to determine aflatoxins in peanut samples. The results show that the recoveries of the four aflatoxins range from 85.1% to 100.8% with the relative standard deviations between 2.1% and 7.9%. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimization and Scale-up of Inulin Extraction from Taraxacum kok-saghyz roots.

PubMed

Hahn, Thomas; Klemm, Andrea; Ziesse, Patrick; Harms, Karsten; Wach, Wolfgang; Rupp, Steffen; Hirth, Thomas; Zibek, Susanne

2016-05-01

The optimization and scale-up of inulin extraction from Taraxacum kok-saghyz Rodin was successfully performed. Evaluating solubility investigations, the extraction temperature was fixed at 85 degrees C. The inulin stability regarding degradation or hydrolysis could be confirmed by extraction in the presence of model inulin. Confirming stability at the given conditions the isolation procedure was transferred from a 1 L- to a 1 m3-reactor. The Reynolds number was selected as the relevant dimensionless number that has to remain constant in both scales. The stirrer speed in the large scale was adjusted to 3.25 rpm regarding a 300 rpm stirrer speed in the 1 L-scale and relevant physical and process engineering parameters. Assumptions were confirmed by approximately homologous extraction kinetics in both scales. Since T. kok-saghyz is in the focus of research due to its rubber content side-product isolation from residual biomass it is of great economic interest. Inulin is one of these additional side-products that can be isolated in high quantity (- 35% of dry mass) and with a high average degree of polymerization (15.5) in large scale with a purity of 77%.

Selective enrichment in bioactive compound from Kniphofia uvaria by super/subcritical fluid extraction and centrifugal partition chromatography.

PubMed

Duval, Johanna; Destandau, Emilie; Pecher, Virginie; Poujol, Marion; Tranchant, Jean-François; Lesellier, Eric

2016-05-20

Nowadays, a large portion of synthetic products (active cosmetic and therapeutic ingredients) have their origin in natural products. Kniphofia uvaria is a plant from Africa which has proved in the past by in-vivo tests an antioxidant activity due to compounds present in roots. Recently, we have observed anthraquinones in K. uvaria seeds extracts. These derivatives are natural colorants which could have interesting bioactive potential. The aim of this study was to obtain an extract enriched in anthraquinones from K. uvaria seeds which mainly contains glycerides. First, the separation of the seed compounds was studied by using supercritical fluid chromatography (SFC) in the goal to provide a rapid quantification method of these bioactive compounds. A screening of numerous polar stationary phases was achieved for selecting the most suited phase to the separation of the four anthraquinones founded in the seeds. A gradient elution was optimized for improving the separation of the bioactive compounds from the numerous other families of major compounds of the extracts (fatty acids, di- and triglycerides). Besides, a non-selective and green Supercritical Fluid Extraction (SFE) with pure CO2 was applied to seeds followed by a Centrifugal Partition Chromatography (CPC). The CPC system was optimized by using the Arizona phase system, to enrich the extract in anthraquinones. Two systems were selected to isolate the bioactive compounds from the oily extract with varied purity target. The effect of the injection mode for these very viscous samples was also studied. Finally, in order to directly apply a selective process of extraction to the seeds, the super/subcritical fluid extraction was optimized to increase the anthraquinone yield in the final extract, by studying varied modifier compositions and nature, as well as different temperatures and backpressures. Conditions suited to favour an enrichment factor bases on the ratio of anthraquinone and trilycerides extracted are described. Copyright © 2016 Elsevier B.V. All rights reserved.

ANTIOXIDANT AND ANTIFUNGAL ACTIVITY OF SELECTED MEDICINAL PLANT EXTRACTS AGAINST PHYTOPATHOGENIC FUNGI

PubMed Central

Mahlo, Salome Mamokone; Chauke, Hasani Richard; McGaw, Lyndy; Eloff, Jacobus

2016-01-01

Background: Medicinal plants are used by many ethnic groups as a source of medicine for the treatment of various ailments in both humans and domestic animals. These plants produce secondary metabolites that have antimicrobial properties, thus screening of medicinal plants provide another alternative for producing chemical fungicides that are relatively non-toxic and cost-effective. Materials and methods: Leaf extracts of selected South African plant species (Bucida buceras, Breonadia salicina, Harpephyllum caffrum, Olinia ventosa, Vangueria infausta and Xylotheca kraussiana) were investigated for activity against selected phytopathogenic fungi (Aspergillus niger, Aspergillus parasiticus, Colletotricum gloeosporioides, Penicillium janthinellum, P. expansum, Trichoderma harzianum and Fusarium oxysporum). These plant fungal pathogens causes major economic losses in fruit industry such as blue rot on nectaries and postharvest disease in citrus. Plant species were selected from 600 evaluated inter alia, against two animal fungal pathogens (Candida albicans and Cryptococcus neoformans). Antioxidant activity of the selected plant extracts were investigated using a qualitative assay (2, 2-diphenyl-1-picrylhydrazyl (DPPH)). Bioautography assay was used to determine the number of antifungal compounds in plant extracts. Results: All plant extracts were active against the selected plant phytopathogenic fungi. Moreover, Bucida buceras had the best antifungal activity against four of the fungi, with minimum inhibitory concentration (MIC) values as low as 0.02 mg/ml and 0.08 mg/ml against P. expansum, P. janthinellum, T. harzianum and F. oxysporum. The plant extracts of five plant species did not possess strong antioxidant activity. However, methanol extract of X. kraussiana was the most active radical scavenger in the DPPH assay amongst the six medicinal plants screened. No antifungal compounds were observed in some of the plant extracts with good antifungal activity as shown in the microdilution assay, indicating possible synergism between the separated metabolites. Conclusion: The results showed that acetone was the best extractant. Furthermore, our findings also confirm the traditional use of Breonadia salicina and demonstrate the potential value of developing biopesticides from plants. PMID:28852739

ANTIOXIDANT AND ANTIFUNGAL ACTIVITY OF SELECTED MEDICINAL PLANT EXTRACTS AGAINST PHYTOPATHOGENIC FUNGI.

PubMed

Mahlo, Salome Mamokone; Chauke, Hasani Richard; McGaw, Lyndy; Eloff, Jacobus

2016-01-01

Medicinal plants are used by many ethnic groups as a source of medicine for the treatment of various ailments in both humans and domestic animals. These plants produce secondary metabolites that have antimicrobial properties, thus screening of medicinal plants provide another alternative for producing chemical fungicides that are relatively non-toxic and cost-effective. Leaf extracts of selected South African plant species ( Bucida buceras, Breonadia salicina, Harpephyllum caffrum, Olinia ventosa, Vangueria infausta and Xylotheca kraussiana ) were investigated for activity against selected phytopathogenic fungi ( Aspergillus niger, Aspergillus parasiticus, Colletotricum gloeosporioides, Penicillium janthinellum, P. expansum, Trichoderma harzianum and Fusarium oxysporum ). These plant fungal pathogens causes major economic losses in fruit industry such as blue rot on nectaries and postharvest disease in citrus. Plant species were selected from 600 evaluated inter alia, against two animal fungal pathogens ( Candida albicans and Cryptococcus neoformans ). Antioxidant activity of the selected plant extracts were investigated using a qualitative assay (2, 2-diphenyl-1-picrylhydrazyl (DPPH)). Bioautography assay was used to determine the number of antifungal compounds in plant extracts. All plant extracts were active against the selected plant phytopathogenic fungi. Moreover, Bucida buceras had the best antifungal activity against four of the fungi, with minimum inhibitory concentration (MIC) values as low as 0.02 mg/ml and 0.08 mg/ml against P. expansum, P. janthinellum, T. harzianum and F. oxysporum . The plant extracts of five plant species did not possess strong antioxidant activity. However, methanol extract of X. kraussiana was the most active radical scavenger in the DPPH assay amongst the six medicinal plants screened. No antifungal compounds were observed in some of the plant extracts with good antifungal activity as shown in the microdilution assay, indicating possible synergism between the separated metabolites. The results showed that acetone was the best extractant. Furthermore, our findings also confirm the traditional use of Breonadia salicina and demonstrate the potential value of developing biopesticides from plants.

Optimization of a sensitive method for the determination of nitro musk fragrances in waters by solid-phase microextraction and gas chromatography with micro electron capture detection using factorial experimental design.

PubMed

Polo, Maria; Garcia-Jares, Carmen; Llompart, Maria; Cela, Rafael

2007-08-01

A solid-phase microextraction method (SPME) followed by gas chromatography with micro electron capture detection for determining trace levels of nitro musk fragrances in residual waters was optimized. Four nitro musks, musk xylene, musk moskene, musk tibetene and musk ketone, were selected for the optimization of the method. Factors affecting the extraction process were studied using a multivariate approach. Two extraction modes (direct SPME and headspace SPME) were tried at different extraction temperatures using two fiber coatings [Carboxen-polydimethylsiloxane (CAR/PDMS) and polydimethylsiloxane-divinylbenzene (PDMS/DVB)] selected among five commercial tested fibers. Sample agitation and the salting-out effect were also factors studied. The main effects and interactions between the factors were studied for all the target compounds. An extraction temperature of 100 degrees C and sampling the headspace over the sample, using either CAR/PDMS or PDMS/DVB as fiber coatings, were found to be the experimental conditions that led to a more effective extraction. High sensitivity, with detection limits in the low nanogram per liter range, and good linearity and repeatability were achieved for all nitro musks. Since the method proposed performed well for real samples, it was applied to different water samples, including wastewater and sewage, in which some of the target compounds (musk xylene and musk ketone) were detected and quantified.

Selective recovery of cobalt, nickel and lithium from sulfate leachate of cathode scrap of Li-ion batteries using liquid-liquid extraction

NASA Astrophysics Data System (ADS)

Nguyen, Viet Tu; Lee, Jae-chun; Jeong, Jinki; Kim, Byung-Su; Pandey, B. D.

2014-03-01

This paper focuses on the extractive separation and selective recovery of cobalt, nickel and lithium from the sulfate leachate of cathode scrap generated during manufacture of lithium ion batteries (LIBs). The conditions for extraction, scrubbing and stripping of cobalt from nickel and lithium are optimized with an aqueous feed containing 25.1 g·dm-3 cobalt, 2.54 g·dm-3 nickel and 6.2 g·dm-3 lithium using Na-PC-88A. 99.8% Co is extracted with 60% Na-0.56 mol·dm-3 PC-88A in two counter-current stages at an O/A phase ratio of 3/1 and an equilibrium pH of 4.5. The "crowding effect" shown for the first time provides effective scrubbing of impurities (Ni and Li) with 2.0 g·dm-3 CoSO4 solution. The McCabe-Thiele diagram predicts the scrubbing of 99.9% Ni and 99.9% Li at an equilibrium pH of 4.75 and O/A of 2/1 in two stages. High purity (99.9%) cobalt sulfate along with Ni and Li from the leach liquor of cathode scrap is recovered by solvent extraction. The proposed process ensures complete recycling of the waste of the manufacturing process of LIBs.

ON-SITE SOLID PHRASE EXTRACTION AND LABORATORY ...

EPA Pesticide Factsheets

Fragrance materials, such as synthetic musks in aqueous samples, are normally analyzed by GC/MS in the selected ion monitoring (SIM) mode to provide maximum sensitivity after liquid-liquid extraction of I -L samples. A I -L sample, however, usually provides too little analyte for full-scan data acquisition. An on-site extraction method for extracting synthetic musks from 60 L of wastewater effluent has been developed. Such a large sample volume permits high-quality, full-scan mass spectra to be obtained for various synthetic musk compounds. Quantification of these compounds was conveniently achieved from the full-scan data directly, without preparing SIM descriptors for each compound to acquire SIM data. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-sol

IN SITU SOLID-PHASE EXTRACTION AND ANALYSIS OF ...

EPA Pesticide Factsheets

Fragrance materials, such as synthetic musks in aqueous samples, are normally analyzed by GC/MS in the selected ion monitoring (SIM) mode to provide maximum sensitivity after liquid-liquid extraction of 1-L samples. A 1-L sample, however, usually provides too little analyte for full-scan data acquisition.We have developed an on-site extraction method for extracting synthetic musks from 60 L of wastewater effluent. Such a large sample volume permits high-quality, full-scan mass spectra to be obtained for various synthetic musk compounds. Quantification of these compounds was conveniently achieved from the full-scan data directly, without preparing SIM descriptors for each compound to acquire SIM data. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-s

In vitro activities of plant extracts on human Loa loa isolates and cytotoxicity for eukaryotic cells.

PubMed

Mengome, Line-Edwige; Akue, Jean Paul; Souza, Alain; Feuya Tchoua, Guy Raymond; Nsi Emvo, Edouard

2010-08-01

Loa loa, a filarial worm, can cause fatal encephalitis in humans. In an attempt to find alternatives to the standard treatments (ivermectin and diethylcarbamazine citrate), we tested 12 methanolic extracts of nine traditional plant remedies. The extracts (100-0.09 microg/ml) were incubated with 20 Loa loa microfilariae isolated from patients at 37 degrees C with 5% CO(2) in modified Eagle's medium supplemented with 10% fetal serum and antibiotics. Activity was evaluated 120 h later by counting live microfilariae under a microscope. Cytotoxicity for eukaryotic cells was estimated by measuring 3-[4,5-dimethylthiazol-2-yl]-2-5 diphenyl tetrazolium bromide transformation to formazan at 450 nM in a spectrophotometer. The plants tested were Lophira alata, Greenwayodendron suaveolens, Uapaca togoensis, Zanthoxylum heitzii, Peperomia pellucida, Piptadeniastrum africanum, Petersianthus macrocarpus, Vernonia conferta, and Vernonia hymenolepis. Chemical screening showed that most of the extracts contained reducing sugars, tannin or polyphenols, sterols or triterpenes, saponosides, and alkaloids. None contained carotinoids and few contained flavonoids. The 50% lethal concentration ranged from 0.22 to 70.28 microg/ml, while the 50% inhibitory concentration for eukaryotic cells (IC(50)) ranged from 8.52 to 119.52 microg/ml. Extracts of P. macrocarpus (selectivity index = 72.16), P. africanum (13.69), Z. heitzii (12.11), and L. alata (9.26) were highly selective for L. loa.

Mode of occurrence of arsenic in feed coal and its derivative fly ash, Black Warrior Basin, Alabama

USGS Publications Warehouse

Zielinski, R.A.; Foster, A.L.; Meeker, G.P.; Brownfield, I.K.

2007-01-01

An arsenic-rich (As = 55 ppm) bituminous feed coal from the Black Warrior Basin, Alabama and its derivative fly ash (As = 230 ppm) were selected for detailed investigation of arsenic residence and chemical forms. Analytical techniques included microbeam analysis, selective extraction, and As K-edge X-ray absorption fine-structure (XAFS) spectroscopy. Most As in the coal is contained in a generation of As-bearing pyrite (FeS2) that formed in response to epigenetic introduction of hydrothermal fluids. XAFS results indicate that approximately 50% of the As in the coal sample occurs as the oxidized As(V) species, possibly the result of incipient oxidation of coal and pyrite prior to our analysis. Combustion of pyrite and host coal produced fly ash in which 95% of As is present as As(V). Selective extraction of the fly ash with a carbonate buffer solution (pH = 10) removed 49% of the As. A different extraction with an HCl-NH2OH mixture, which targets amorphous and poorly crystalline iron oxides, dissolved 79% of the As. XAFS spectroscopy of this highly acidic (pH = 3.0) fly ash indicated that As is associated with some combination of iron oxide, oxyhydroxide, or sulfate. In contrast, a highly alkaline (pH = 12.7) fly ash from Turkey shows most As associated with a phase similar to calcium orthoarsenate (Ca3(AsO4)2). The combined XAFS results indicate that fly ash acidity, which is determined by coal composition and combustion conditions, may serve to predict arsenic speciation in fly ash.

Photoelectrochemical detection of benzaldehyde in foodstuffs

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaCourse, W.R.; Krull, I.S.

Photoelectrochemical detection (PED) coupled with high performance liquid chromatography was used to quantitatively determine benzaldehyde in extracts, beverages, and foodstuffs. Photoelectrochemical detection is responsive to alkyl and aryl ketones and aldehydes and offers the advantages of 2-3 orders of magnitude linearity, 5-1-ng limits of detection, and a high degree of selectivity without chemical derivatization. This is the first application of the PED to sample analysis.

Boronate affinity-based surface molecularly imprinted polymers using glucose as fragment template for excellent recognition of glucosides.

PubMed

Peng, Mijun; Xiang, Haiyan; Hu, Xin; Shi, Shuyun; Chen, Xiaoqing

2016-11-25

Rapid and efficient extraction of bioactive glycosides from complex natural origins poses a difficult challenge, and then is often inherent bottleneck for their highly utilization. Herein, we propose a strategy to fabricate boronate affinity based surface molecularly imprinted polymers (MIPs) for excellent recognition of glucosides. d-glucose was used as fragment template. Boronic acid, dynamic covalent binding with d-glucose under different pH conditions, was selected as functional monomer to improve specificity. Fe 3 O 4 solid core for surface imprinting using tetraethyl orthosilicate (TEOS) as crosslinker could control imprinted shell thickness for favorable adsorption capacity and satisfactory mass transfer rate, improve hydrophilicity, separate easily by a magnet. Model adsorption studies showed that the resulting MIPs show specific recognition of glucosides. The equilibrium data fitted well to Langmuir equation and the adsorption process could be described by pseudo-second order model. Furthermore, the MIPs were successfully applied for selective extraction of three flavonoid glucosides (daidzin, glycitin, and genistin) from soybean. Results indicated that selective extraction of glucosides from complex aqueous media based on the prepared MIPs is simple, rapid, efficient and specific. Moreover, this method opens up a universal route for imprinting saccharide with cis-diol group for glycosides recognition. Copyright © 2016 Elsevier B.V. All rights reserved.

Oriented modulation for watermarking in direct binary search halftone images.

PubMed

Guo, Jing-Ming; Su, Chang-Cheng; Liu, Yun-Fu; Lee, Hua; Lee, Jiann-Der

2012-09-01

In this paper, a halftoning-based watermarking method is presented. This method enables high pixel-depth watermark embedding, while maintaining high image quality. This technique is capable of embedding watermarks with pixel depths up to 3 bits without causing prominent degradation to the image quality. To achieve high image quality, the parallel oriented high-efficient direct binary search (DBS) halftoning is selected to be integrated with the proposed orientation modulation (OM) method. The OM method utilizes different halftone texture orientations to carry different watermark data. In the decoder, the least-mean-square-trained filters are applied for feature extraction from watermarked images in the frequency domain, and the naïve Bayes classifier is used to analyze the extracted features and ultimately to decode the watermark data. Experimental results show that the DBS-based OM encoding method maintains a high degree of image quality and realizes the processing efficiency and robustness to be adapted in printing applications.

Analysis of protein phosphorylation by monolithic extraction columns based on poly(divinylbenzene) containing embedded titanium dioxide and zirconium dioxide nano-powders.

PubMed

Rainer, Matthias; Sonderegger, Harald; Bakry, Rania; Huck, Christian W; Morandell, Sandra; Huber, Lukas A; Gjerde, Douglas T; Bonn, Günther K

2008-11-01

The potential of an organic monolith with incorporated titanium dioxide (TiO(2)) and zirconium dioxide (ZrO(2)) nanoparticles was evaluated for the selective enrichment of phosphorylated peptides from tryptic digests. A pipette tip was fitted with a monolith based on divinylbenzene (DVB) of highly porous structure, which allows sample to pass through the monolithic bed. The enrichment of phosphopeptides was enhanced by increasing the pipetting cycles during the sample preparation and a higher recovery could be achieved with adequate buffer systems. A complete automated process was developed for enrichment of phosphopeptides leading to high reproducibility and resulting in a robust method designed to minimize analytical variance while providing high sensitivity at high sample throughput. The effect of particle size on the selectivity of phosphopeptides was investigated by comparative studies with nano- and microscale TiO(2) and ZrO(2) powders. Eleven phosphopeptides from alpha-casein digest could be recovered by an optimized mixture of microscale TiO(2)/ZrO(2) particles, whereas nine additional phosphopeptides could be retained by the same mixture of nano-structured material. When compared to conventional immobilized metal-ion affinity chromatography and commercial phosphorylation-enrichment kits, higher selectivity was observed in case of self fabricated tips. About 20 phosphopeptides could be retained from alpha-casein and five from beta-casein digests by using TiO(2) and ZrO(2) based extraction tips. Further selectivity for phosphopeptides was demonstrated by enriching a digest of in vitro phosphorylated extracellular signal regulated kinase 1 (ERK1). Two phosphorylated peptides of ERK1 could be identified by MALDI-MS/MS measurements and a following MASCOT database search.

3D-printed, TiO2 NP-incorporated minicolumn coupled with ICP-MS for speciation of inorganic arsenic and selenium in high-salt-content samples.

PubMed

Su, Cheng-Kuan; Chen, Wei-Cheng

2018-04-25

To extend the applicability of solid phase extraction devices manufactured using 3D printing technologies, a stereolithographic 3D printer and resins incorporating titanium dioxide nanoparticles (TiO 2 NPs) were employed to fabricate a demountable minicolumn with TiO 2 NP-incorporated packing as a sample pretreatment device for the selective extraction of inorganic As and Se species from high-salt-content samples, and to facilitate their analyses when coupled to an inductively coupled plasma mass spectrometer. After optimization, the automatic system enabled highly sensitive determinations of As and Se species with detection limits as low as 0.004-0.033 μg L -1 for As and 0.061-0.128 μg L -1 for Se. Reliability was confirmed through analyses of the reference materials 1643f, SLEW-3, CASS-4, and 2670a, as well as spike analyses of samples of water and human urine. These 3D-printed minicolumns appear to be very useful for multi-elemental speciation of these elements from high-salt-content samples. Thus, the incorporation of active nanomaterials into raw printing resins can enable 3D printing technologies-not only to fabricate functionalized devices for diverse sample pretreatment applications but also to encourage the future development of multifunctional devices for analytical science. Graphical abstract Schematic presentation of a demountable minicolumn fabricated using a stereolithographic 3D printer and the resins incorporating with TiO 2 NPs. They were used to selectively extract As and Se species through controlling the sample acidities.

Evaluating bis(2-ethylhexyl) methanediphosphonic acid (H 2DEH[MDP]) based polymer ligand film (PLF) for plutonium and uranium extraction

DOE PAGES

Rim, Jung H.; Armenta, Claudine E.; Gonzales, Edward R.; ...

2015-09-12

This paper describes a new analyte extraction medium called polymer ligand film (PLF) that was developed to rapidly extract radionuclides. PLF is a polymer medium with ligands incorporated in its matrix that selectively and quickly extracts analytes. The main focus of the new technique is to shorten and simplify the procedure for chemically isolating radionuclides for determination through alpha spectroscopy. The PLF system was effective for plutonium and uranium extraction. The PLF was capable of co-extracting or selectively extracting plutonium over uranium depending on the PLF composition. As a result, the PLF and electrodeposited samples had similar alpha spectra resolutions.

Evaluation of methods for the extraction of DNA from drinking water distribution system biofilms.

PubMed

Hwang, Chiachi; Ling, Fangqiong; Andersen, Gary L; LeChevallier, Mark W; Liu, Wen-Tso

2012-01-01

While drinking water biofilms have been characterized in various drinking water distribution systems (DWDS), little is known about the impact of different DNA extraction methods on the subsequent analysis of microbial communities in drinking water biofilms. Since different DNA extraction methods have been shown to affect the outcome of microbial community analysis in other environments, it is necessary to select a DNA extraction method prior to the application of molecular tools to characterize the complex microbial ecology of the DWDS. This study compared the quantity and quality of DNA yields from selected DWDS bacteria with different cell wall properties using five widely used DNA extraction methods. These were further selected and evaluated for their efficiency and reproducibility of DNA extraction from DWDS samples. Terminal restriction fragment length analysis and the 454 pyrosequencing technique were used to interpret the differences in microbial community structure and composition, respectively, from extracted DNA. Such assessments serve as a concrete step towards the determination of an optimal DNA extraction method for drinking water biofilms, which can then provide a reliable comparison of the meta-analysis results obtained in different laboratories.

Molecularly Imprinted Polymers for Ochratoxin A Extraction and Analysis

PubMed Central

Yu, Jorn C. C.; Lai, Edward P. C.

2010-01-01

Molecularly imprinted polymers (MIPs) are considered as polymeric materials that mimic the functionality of antibodies. MIPs have been utilized for a wide variety of applications in chromatography, solid phase extraction, immunoassays, and sensor recognition. In this article, recent advances of MIPs for the extraction and analysis of ochratoxins are discussed. Selection of functional monomers to bind ochratoxin A (OTA) with high affinities, optimization of extraction procedures, and limitations of MIPs are compared from different reports. The most relevant examples in the literature are described to clearly show how useful these materials are. Strategies on MIP preparation and schemes of analytical methods are also reviewed in order to suggest the next step that would make better use of MIPs in the field of ochratoxin research. The review ends by outlining the remaining issues and impediments. PMID:22069649

On-site comprehensive analysis of explosives using HPLC-UV-PAED

NASA Astrophysics Data System (ADS)

Marple, Ronita L.; LaCourse, William R.

2004-03-01

High-performance liquid chromatography with ultra violet and photo-assisted electrochemical detection (HPLC-UV-PAED) has been developed for the sensitive and selective detection of explosives in ground water and soil extracts. Fractionation and preconcentration of explosives is accomplished with on-line solid phase extraction (SPE), which minimizes sample pretreatment and enables faster and more accurate on-site assessment of a contaminated site. Detection limits are equivalent or superior (i.e., <1 part-per-trillion for HMX) to those achieved using the Environmental Protection Agency (EPA) Method 8330. This approach is more broadly applicable, as it is capable of determining a wider range of organic nitro compounds. Soil samples are extracted using pressurized fluid extraction (PFE), and this technique is automatable, field-compatible, and environmentally friendly, adding to the overall efficiency of the methodology.

Enhanced extraction of butyric acid under high-pressure CO2 conditions to integrate chemical catalysis for value-added chemicals and biofuels.

PubMed

Chun, Jaesung; Choi, Okkyoung; Sang, Byoung-In

2018-01-01

Extractive fermentation with the removal of carboxylic acid requires low pH conditions because acids are better partitioned into the solvent phase at low pH values. However, this requirement conflicts with the optimal near-neutral pH conditions for microbial growth. CO 2 pressurization was used, instead of the addition of chemicals, to decrease pH for the extraction of butyric acid, a fermentation product of Clostridium tyrobutyricum , and butyl butyrate was selected as an extractant. CO 2 pressurization (50 bar) improved the extraction efficiency of butyric acid from a solution at pH 6, yielding a distribution coefficient ( D ) 0.42. In situ removal of butyric acid during fermentation increased the production of butyric acid by up to 4.10 g/L h, an almost twofold increase over control without the use of an extraction process. In situ extraction of butyric acid using temporal CO 2 pressurization may be applied to an integrated downstream catalytic process for upgrading butyric acid to value-added chemicals in an organic solvent.

Antioxidant properties and phenolic profile characterization by LC-MS/MS of selected Tunisian pomegranate peels.

PubMed

Abid, Mouna; Yaich, Héla; Cheikhrouhou, Salma; Khemakhem, Ibtihel; Bouaziz, Mohamed; Attia, Hamadi; Ayadi, M A

2017-08-01

Antioxidant contents and activities of different extracts from four Tunisian pomegranate peels, locally called "Acide", "Gabsi", "Nebli" and "Tounsi", were studied. Peels samples were extracted with three solvents (water, ethanol and acetone). For each extract, the total phenol contents and antioxidant activity were evaluated. The highest values of polyphenol, tannins, flavonoids and anthocyanins were recorded in the acetone extract of Acide ecotype with 304.6 mg gallic acid equivalent/g; 292.23 mg gallic acid equivalent/g; 15.46 mg Quercetin/g and 54.51 mg cy-3-glu/100 g, respectively. The acetone extract of Acide ecotype also showed the highest free radical-scavenging and reducing power activity compared to other extracts. Besides, the phytochemical analysis by LC-MS/MS revealed a high content of ellagitannins with punicalagin and punicalagin derivatives as the major compounds that might be responsible for promising antioxidant activity of pomegranate peel extracts. Two compounds (Castalagin derivative and Galloyl-bis-HHDP-hex derivative) were detected only in "Acide" ecotype in important contents.

High-resolution gas chromatography/mass spectrometry method for characterization and quantitative analysis of ginkgolic acids in Ginkgo biloba plants, extracts, and dietary supplements.

PubMed

Wang, Mei; Zhao, Jianping; Avula, Bharathi; Wang, Yan-Hong; Avonto, Cristina; Chittiboyina, Amar G; Wylie, Philip L; Parcher, Jon F; Khan, Ikhlas A

2014-12-17

A high-resolution gas chromatography/mass spectrometry (GC/MS) with selected ion monitor method focusing on the characterization and quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba L. plant materials, extracts, and commercial products was developed and validated. The method involved sample extraction with (1:1) methanol and 10% formic acid, liquid-liquid extraction with n-hexane, and derivatization with trimethylsulfonium hydroxide (TMSH). Separation of two saturated (C13:0 and C15:0) and six unsaturated ginkgolic acid methyl esters with different positional double bonds (C15:1 Δ8 and Δ10, C17:1 Δ8, Δ10, and Δ12, and C17:2) was achieved on a very polar (88% cyanopropyl) aryl-polysiloxane HP-88 capillary GC column. The double bond positions in the GAs were determined by ozonolysis. The developed GC/MS method was validated according to ICH guidelines, and the quantitation results were verified by comparison with a standard high-performance liquid chromatography method. Nineteen G. biloba authenticated and commercial plant samples and 21 dietary supplements purported to contain G. biloba leaf extracts were analyzed. Finally, the presence of the marker compounds, terpene trilactones and flavonol glycosides for Ginkgo biloba in the dietary supplements was determined by UHPLC/MS and used to confirm the presence of G. biloba leaf extracts in all of the botanical dietary supplements.

Alkaline-side extraction of technetium from tank waste using crown ethers and other extractants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bonnesen, P.V.; Moyer, B.A.; Presley, D.J.

The chemical development of a new crown-ether-based solvent-extraction process for the separation of (Tc) from alkaline tank-waste supernate is ready for counter-current testing. The process addresses a priority need in the proposed cleanup of Hanford and other tank wastes. This need has arisen from concerns due to the volatility of Tc during vitrification, as well as {sup 99}Tc`s long half-life and environmental mobility. The new process offers several key advantages that direct treatability--no adjustment of the waste composition is needed; economical stripping with water; high efficiency--few stages needed; non-RCRA chemicals--no generation of hazardous or mixed wastes; co-extraction of {sup 90}Sr;more » and optional concentration on a resin. A key concept advanced in this work entails the use of tandem techniques: solvent extraction offers high selectivity, while a subsequent column sorption process on the aqueous stripping solution serves to greatly concentrate the Tc. Optionally, the stripping solution can be evaporated to a small volume. Batch tests of the solvent-extraction and stripping components of the process have been conducted on actual melton Valley Storage Tank (MVST) waste as well as simulants of MVST and Hanford waste. The tandem process was demonstrated on MVST waste simulants using the three solvents that were selected the final candidates for the process. The solvents are 0.04 M bis-4,4{prime}(5{prime})[(tert-butyl)cyclohexano]-18-crown-6 (abbreviated di-t-BuCH18C6) in a 1:1 vol/vol blend of tributyl phosphate and Isopar{reg_sign} M (an isoparaffinic kerosene); 0.02 M di-t-BuCH18C6 in 2:1 vol/vol TBP/Isopar M and pure TBP. The process is now ready for counter-current testing on actual Hanford tank supernates.« less

Some Modest Proposals

ERIC Educational Resources Information Center

Wrigley, Terry

2017-01-01

This text represents two extracts from a submission to the House of Commons Select Committee's investigation into primary school tests. The first part is a critique of the 2016 tests, particularly the Reading and Grammar tests for 11-year-olds and also the highly regulated "teacher assessment" of Writing. The second part is a set of…

Selected castorbean genotypes evaluated for morphological traits, seed yield, fatty acids, and oil content

USDA-ARS?s Scientific Manuscript database

Castorbean, Ricinus communis, contains oil used in pharmaceutics, cosmetics, soap, shampoo, and as a lubricant. Castorbean is rapidly becoming a biodiesel crop because of its high oil content which ranges between 30 and 60% depending upon extraction proceedures. Two hundred and three castorbean acce...

Graphene oxide-based composite monolith as new sorbent for the on-line solid phase extraction and high performance liquid chromatography determination of ß-sitosterol in food samples.

PubMed

Cui, Beijiao; Guo, Bin; Wang, Huimin; Zhang, Doudou; Liu, Haiyan; Bai, Ligai; Yan, Hongyuan; Han, Dandan

2018-08-15

A composite monolithic column was prepared by redox initiation method for the on-line purification and enrichment of β-sitosterol, in which graphene oxide (GO) was embedded. The obtained monolithic column was characterized by scanning electron microscopy (SEM) and nitrogen adsorption-desorption isotherm measurement, which indicated that the monolith possessed characteristics of porous structure and high permeability. Under the optimum conditions for extraction and determination, the calibration equation was y = 47.92 × -0.1391; the linear range was 0.008-1.0 mg mL -1 ; the linear regression coefficient was 0.998; the limit of detection (LOD) is 2.4 μg mL -1 ; the limit of quantitation (LOQ) was 8 μg mL -1 ; precisions for intra-day and inter-day assays presented as relative standard deviations were less than 4.3% and 6.8%, respectively. Under the selective conditions, the enrichment factor of the method was 119. The recovery was in the range of 80.40-98.00%. Moreover, the adsorption amount of the monolith was compared with silica gel-C18 adsorbent and the monolith without graphene oxide being embedded. The polymerization monolithic column showed high selectivity and good permeability, and it was successfully used as on-line solid-phase extraction (SPE) column for determination of β-sitosterol in edible oil. Copyright © 2018 Elsevier B.V. All rights reserved.

Computational and experimental investigation of molecular imprinted polymers for selective extraction of dimethoate and its metabolite omethoate from olive oil.

PubMed

Bakas, Idriss; Oujji, Najwa Ben; Moczko, Ewa; Istamboulie, Georges; Piletsky, Sergey; Piletska, Elena; Ait-Addi, Elhabib; Ait-Ichou, Ihya; Noguer, Thierry; Rouillon, Régis

2013-01-25

This work presents the development of molecularly imprinted polymers (MIPs) for the selective extraction of dimethoate from olive oil. Computational simulations allowed selecting itaconic acid as the monomer showing the highest affinity towards dimethoate. Experimental validation confirmed modelling predictions and showed that the polymer based on IA as functional monomer and omethoate as template molecule displays the highest selectivity for the structurally similar pesticides dimethoate, omethoate and monocrotophos. Molecularly imprinted solid phase extraction (MISPE) method was developed and applied to the clean-up of olive oil extracts. It was found that the most suitable solvents for loading, washing and elution step were respectively hexane, hexane-dichloromethane (85:15%) and methanol. The developed MIPSE was successfully applied to extraction of dimethoate from olive oil, with recovery rates up to 94%. The limits of detection and quantification of the described method were respectively 0.012 and 0.05 μg g(-1). Copyright © 2012 Elsevier B.V. All rights reserved.

Classification Influence of Features on Given Emotions and Its Application in Feature Selection

NASA Astrophysics Data System (ADS)

Xing, Yin; Chen, Chuang; Liu, Li-Long

2018-04-01

In order to solve the problem that there is a large amount of redundant data in high-dimensional speech emotion features, we analyze deeply the extracted speech emotion features and select better features. Firstly, a given emotion is classified by each feature. Secondly, the recognition rate is ranked in descending order. Then, the optimal threshold of features is determined by rate criterion. Finally, the better features are obtained. When applied in Berlin and Chinese emotional data set, the experimental results show that the feature selection method outperforms the other traditional methods.

Selective probing of mRNA expression levels within a living cell.

PubMed

Nawarathna, D; Turan, T; Wickramasinghe, H Kumar

2009-08-24

We report on a selective and nondestructive measurement of mRNA (messenger ribonucleic acid) expression levels within a living cell. We first modify an atomic force microscope tip to create a tapered nanoscale coaxial cable. Application of an ac (alternating potential) between the inner and outer electrodes of this cable creates a dielectrophoretic force attracting mRNA molecules toward the tip-end which is pretreated with gene specific primers. We selectively extracted and analyzed both high ( approximately 2500) and extremely low (11 0) copy number mRNA from a living cell mRNA in less than 10 s.

Solvent extraction of gold using ionic liquid based process

NASA Astrophysics Data System (ADS)

Makertihartha, I. G. B. N.; Zunita, Megawati; Rizki, Z.; Dharmawijaya, P. T.

2017-01-01

In decades, many research and mineral processing industries are using solvent extraction technology for metal ions separation. Solvent extraction technique has been used for the purification of precious metals such as Au and Pd, and base metals such as Cu, Zn and Cd. This process uses organic compounds as solvent. Organic solvents have some undesired properties i.e. toxic, volatile, excessive used, flammable, difficult to recycle, low reusability, low Au recovery, together with the problems related to the disposal of spent extractants and diluents, even the costs associated with these processes are relatively expensive. Therefore, a lot of research have boosted into the development of safe and environmentally friendly process for Au separation. Ionic liquids (ILs) are the potential alternative for gold extraction because they possess several desirable properties, such as a the ability to expanse temperature process up to 300°C, good solvent properties for a wide range of metal ions, high selectivity, low vapor pressures, stability up to 200°C, easy preparation, environmentally friendly (commonly called as "green solvent"), and relatively low cost. This review paper is focused in investigate of some ILs that have the potentials as solvent in extraction of Au from mineral/metal alloy at various conditions (pH, temperature, and pressure). Performances of ILs extraction of Au are studied in depth, i.e. structural relationship of ILs with capability to separate Au from metal ions aggregate. Optimal extraction conditon in order to gain high percent of Au in mineral processing is also investigated.

An improved strategy for skin lesion detection and classification using uniform segmentation and feature selection based approach.

PubMed

Nasir, Muhammad; Attique Khan, Muhammad; Sharif, Muhammad; Lali, Ikram Ullah; Saba, Tanzila; Iqbal, Tassawar

2018-02-21

Melanoma is the deadliest type of skin cancer with highest mortality rate. However, the annihilation in early stage implies a high survival rate therefore, it demands early diagnosis. The accustomed diagnosis methods are costly and cumbersome due to the involvement of experienced experts as well as the requirements for highly equipped environment. The recent advancements in computerized solutions for these diagnoses are highly promising with improved accuracy and efficiency. In this article, we proposed a method for the classification of melanoma and benign skin lesions. Our approach integrates preprocessing, lesion segmentation, features extraction, features selection, and classification. Preprocessing is executed in the context of hair removal by DullRazor, whereas lesion texture and color information are utilized to enhance the lesion contrast. In lesion segmentation, a hybrid technique has been implemented and results are fused using additive law of probability. Serial based method is applied subsequently that extracts and fuses the traits such as color, texture, and HOG (shape). The fused features are selected afterwards by implementing a novel Boltzman Entropy method. Finally, the selected features are classified by Support Vector Machine. The proposed method is evaluated on publically available data set PH2. Our approach has provided promising results of sensitivity 97.7%, specificity 96.7%, accuracy 97.5%, and F-score 97.5%, which are significantly better than the results of existing methods available on the same data set. The proposed method detects and classifies melanoma significantly good as compared to existing methods. © 2018 Wiley Periodicals, Inc.

Question analysis for Indonesian comparative question

NASA Astrophysics Data System (ADS)

Saelan, A.; Purwarianti, A.; Widyantoro, D. H.

2017-01-01

Information seeking is one of human needs today. Comparing things using search engine surely take more times than search only one thing. In this paper, we analyzed comparative questions for comparative question answering system. Comparative question is a question that comparing two or more entities. We grouped comparative questions into 5 types: selection between mentioned entities, selection between unmentioned entities, selection between any entity, comparison, and yes or no question. Then we extracted 4 types of information from comparative questions: entity, aspect, comparison, and constraint. We built classifiers for classification task and information extraction task. Features used for classification task are bag of words, whether for information extraction, we used lexical, 2 previous and following words lexical, and previous label as features. We tried 2 scenarios: classification first and extraction first. For classification first, we used classification result as a feature for extraction. Otherwise, for extraction first, we used extraction result as features for classification. We found that the result would be better if we do extraction first before classification. For the extraction task, classification using SMO gave the best result (88.78%), while for classification, it is better to use naïve bayes (82.35%).

Organomineral Complexation at the Nanoscale: Iron Speciation and Soil Carbon Stabilization

NASA Astrophysics Data System (ADS)

Coward, E.; Thompson, A.; Plante, A. F.

2016-12-01

Much of the uncertainty in the biogeochemical behavior of soil carbon (C) in tropical ecosystems derives from an incomplete understanding of soil C stabilization processes. The 2:1 phyllosilicate clays often associated with temperate organomineral complexation are largely absent in tropical soils due to extensive weathering. In contrast, these soils contain an abundance of Fe- and Al-containing short-range-order (SRO) mineral phases capable of C stabilization through sorption or co-precipitation, largely enabled by high specific surface area (SSA). SRO-mediated organomineral associations may thus prove a critical, yet matrix-selective, driver of the long-term C stabilization capacity observed in tropical soils. Characterizing the interactions between inherently heterogeneous organic matter and amorphous mineralogy presses the limits of current analytical techniques. This work pairs inorganic selective dissolution with high-resolution assessment of Fe speciation to determine the contribution of extracted mineral phases to the mineral matrix, and to C stabilization capacity. Surface (0-20 cm) samples were taken from 20 quantitative soil pits within the Luquillo Critical Zone Observatory in northeast Puerto Rico stratified across granodioritic and volcaniclastic parent materials. 57Fe-Mössbauer spectroscopy (MBS) and x-ray diffraction (XRD) before and after Fe-SOM extraction were used to assess changes in the mineralogical matrix associated with SOM dissolution, while N2-BET sorption was used to determine the contributions of the extractable phases to SSA. Results indicate (1) selective extraction of soil C produces significant shifts in Fe phase distribution, (2) SRO minerals contribute substantially to SSA, and (3) SRO minerals appear protected by more crystalline phases via physical mechanisms, rather than dissolution-dependent chemical bonds. This nanoscale characterization of Fe-C complexes thus provides evidence for both anticipated mineral-organic and unexpected mineral-mineral associations, which may dynamically impact the temporal fate of tropical soil C.

Highly Efficient Extraction of Phenolic Compounds by Use of Magnetic Room Temperature Ionic Liquids for Environmental Remediation

PubMed Central

Deng, Ning; Li, Min; Zhao, Lijie; Lu, Chengfei; de Rooy, Sergio L.; Warner, Isiah M.

2011-01-01

A hydrophobic magnetic room temperature ionic liquid (MRTIL), trihexyltetradecylphosphonium tetrachloroferrate(III) ([3C6PC14][FeCl4]), was synthesized from trihexyltetradecylphosphonium chloride and FeCl3·6H2O. This MRTIL was investigated as a possible separation agent for solvent extraction of phenolic compounds from aqueous solution. Due to its strong paramagnetism, [3C6PC14][FeCl4] responds to an external neodymium magnet, which was employed in the design of a novel magnetic extraction technique. The conditions for extraction, including extraction time, volume ratio between MRTIL and aqueous phase, pH of aqueous solution, and structures of phenolic compounds were investigated and optimized. The magnetic extraction of phenols achieved equilibrium in 20 min and the phenolic compounds were found to have higher distribution ratios under acidic conditions. In addition, it was observed that phenols containing a greater number of chlorine or nitro substitutents exhibited higher distribution ratios. For example, the distribution ratio of phenol (DPh) was 107. In contrast, 3,5-dichlorophenol distribution ratio (D3,5-DCP) had a much higher value of 6372 under identical extraction conditions. When compared with four selected traditional non-magnetic room temperature ionic liquids, our [3C6PC14][FeCl4] exhibited significantly higher extraction efficiency under the same experimental conditions used in this work. Pentachlorophenol, a major component in the contaminated soil sample obtained from a superfund site, was successfully extracted and removed by use of [3C6PC14][FeCl4] with high extraction efficiency. Pentachlorophenol concentration was dramatically reduced from 7.8 μg.mL−1 to 0.2 μg.mL−1 after the magnetic extraction by use of [3C6PC14][FeCl4]. PMID:21783320

The effect of St John’s wort extracts on CYP3A: a systematic review of prospective clinical trials

PubMed Central

Whitten, D L; Myers, S P; Hawrelak, J A; Wohlmuth, H

2006-01-01

Aim The aim of this systematic review was to assess the quality and outcomes of clinical trials investigating the effect of St John’s wort extracts on the metabolism of drugs by CYP3A. Methods Prospective clinical trials assessing the effect of St John’s wort (SJW) extracts on metabolism by CYP3A were identified through computer-based searches (from their inception to May 2005) of Medline, Cinahl, PsycINFO, AMED, Current Contents and Embase, hand-searches of bibliographies of relevant papers and consultation with manufacturers and researchers in the field. Two reviewers selected trials for inclusion, independently extracted data and recorded details on study design. Results Thirty-one studies met the eligibility criteria. More than two-thirds of the studies employed a before-and-after design, less than one-third of the studies used a crossover design, and only three studies were double-blind and placebo controlled. In 12 studies the SJW extract had been assayed, and 14 studies stated the specific SJW extract used. Results from 26 studies, including all of the 19 studies that used high-dose hyperforin extracts (>10 mg day−1), had outcomes consistent with CYP3A induction. The three studies using low-dose hyperforin extracts (<4 mg day−1) demonstrated no significant effect on CYP3A. Conclusion There is reasonable evidence to suggest that high-dose hyperforin SJW extracts induce CYP3A. More studies are required to determine whether decreased CYP3A induction occurs after low-dose hyperforin extracts. Future studies should adopt study designs with a control phase or control group, identify the specific SJW extract employed and provide quantitative analyses of key constituents. PMID:17010103

Development of a flat membrane based device for electromembrane extraction: a new approach for exhaustive extraction of basic drugs from human plasma.

PubMed

Huang, Chuixiu; Eibak, Lars Erik Eng; Gjelstad, Astrid; Shen, Xiantao; Trones, Roger; Jensen, Henrik; Pedersen-Bjergaard, Stig

2014-01-24

In this work, a single-well electromembrane extraction (EME) device was developed based on a thin (100μm) and flat porous membrane of polypropylene supporting a liquid membrane. The new EME device was operated with a relatively large acceptor solution volume to promote a high recovery. Using this EME device, exhaustive extraction of the basic drugs quetiapine, citalopram, amitriptyline, methadone and sertraline was investigated from both acidified water samples and human plasma. The volume of acceptor solution, extraction time, and extraction voltage were found to be important factors for obtaining exhaustive extraction. 2-Nitrophenyl octyl ether was selected as the optimal organic solvent for the supported liquid membrane. From spiked acidified water samples (600μl), EME was carried out with 600μl of 20mM HCOOH as acceptor solution for 15min and with an extraction voltage of 250V. Under these conditions, extraction recoveries were in the range 89-112%. From human plasma samples (600μl), EME was carried out with 600μl of 20mM HCOOH as acceptor solution for 30min and with an extraction voltage of 300V. Under these conditions, extraction recoveries were in the range of 83-105%. When combined with LC-MS, the new EME device provided linearity in the range 10-1000ng/ml for all analytes (R(2)>0.990). The repeatability at low (10ng/ml), medium (100ng/ml), and high (1000ng/ml) concentration level for all five analytes were less than 10% (RSD). The limits of quantification (S/N=10) were found to be in the range 0.7-6.4ng/ml. Copyright © 2013 Elsevier B.V. All rights reserved.

Molecular docking and ex vivo and in vitro anticholinesterase activity studies of Salvia sp. and highlighted rosmarinic acid.

PubMed

Demirezer, Lütfiye Ömür; Gürbüz, Perihan; Kelicen Uğur, Emine Pelin; Bodur, Mine; Özenver, Nadire; Uz, Ayse; Güvenalp, Zühal

2015-01-01

To evaluate acetylcholinesterase (AChE) inhibitory activity and antioxidant capacity of the major molecule from Salvia sp., rosmarinic acid, as a drug candidate molecule for treatment of Alzheimer disease (AD). The AChE inhibitory activity of different extracts from Salvia trichoclada, Salvia verticillata, and Salvia fruticosa was determined by the Ellman and isolated guinea pig ileum methods, and the antioxidant capacity was determined with DPPH. The AChE inhibitory activity of the major molecule rosmarinic acid was determined by in silico docking and isolated guinea pig ileum methods. The methanol extract of Salvia trichoclada showed the highest inhibition on AChE. The same extract and rosmarinic acid showed significant contraction responses on isolated guinea pig ileum. All the extracts and rosmarinic acid showed high radical scavenging capacities. Docking results of rosmarinic acid showed high affinity to the selected target, AChE. In this study in vitro and ex vivo studies and in silico docking research of rosmarinic acid were used simultaneously for the first time. Rosmarinic acid showed promising results in all the methods tested.

Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica papaya Leaf Extracts.

PubMed

Nguyen, Thao T; Parat, Marie-Odile; Hodson, Mark P; Pan, Jenny; Shaw, Paul N; Hewavitharana, Amitha K

2015-12-24

In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer.

Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica Papaya Leaf Extracts

PubMed Central

Nguyen, Thao T.; Parat, Marie-Odile; Hodson, Mark P.; Pan, Jenny; Shaw, Paul N.; Hewavitharana, Amitha K.

2015-01-01

In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer. PMID:26712788

Graphene oxide-coated stir bar sorptive extraction of trace aflatoxins from soy milk followed by high performance liquid chromatography-laser-induced fluorescence detection.

PubMed

Ma, Haiyan; Ran, Congcong; Li, Mengjiao; Gao, Jinglin; Wang, Xinyu; Zhang, Lina; Bian, Jing; Li, Junmei; Jiang, Ye

2018-04-01

Mycotoxins are potential food pollutants produced by fungi. Among them, aflatoxins (AFs) are the most toxic. Therefore, AFs were selected as models, and a sensitive, simple and green graphene oxide (GO)-based stir bar sorptive extraction (SBSE) method was developed for extraction and determination of AFs with high performance liquid chromatography-laser-induced fluorescence detector (HPLC-LIF). This method improved the sensitivity of AFs detection and solved the deposition difficulty of the direct use of GO as adsorbent. Several parameters including a spiked amount of NaCl, stirring rate, extraction time and desorption time were investigated. Under optimal conditions, the quantitative method had low limits of detection of 2.4-8.0 pg/mL, which were better than some reported AFs analytical methods. The developed method has been applied to soy milk samples with good recoveries ranging from 80.5 to 102.3%. The prepared GO-based SBSE can be used as a sensitive screening technique for detecting AFs in soy milk.

Bis-lactam-1,10-phenanthroline (BLPhen), a New Type of Preorganized Mixed N,O-Donor Ligand That Separates Am(III) over Eu(III) with Exceptionally High Efficiency

DOE PAGES

Jansone-Popova, Santa; Ivanov, Alexander S.; Bryantsev, Vyacheslav S.; ...

2017-05-04

Here, we report a new family of preorganized bislactam- 1,10-phenanthroline (BLPhen) complexants that possess both hard and soft donor atoms within a convergent cavity and show unprecedented extraction strength for the trivalent fblock metal ions. BLPhen ligands with saturated and unsaturated δ-lactam rings have notable differences in their affinity and selectivity for Am(III) over Eu(III), with the latter being the most selective mixed N,O-donor extractant of Am(III) reported to date. Saturated BLPhen was crystallized with five Ln(III) nitrates to form charge-neutral 1:1 complexes in the solid state. DFT calculations further elaborate on the variety of effects that dictate the performancemore » of these preorganized compounds.« less

An improved discriminative filter bank selection approach for motor imagery EEG signal classification using mutual information.

PubMed

Kumar, Shiu; Sharma, Alok; Tsunoda, Tatsuhiko

2017-12-28

Common spatial pattern (CSP) has been an effective technique for feature extraction in electroencephalography (EEG) based brain computer interfaces (BCIs). However, motor imagery EEG signal feature extraction using CSP generally depends on the selection of the frequency bands to a great extent. In this study, we propose a mutual information based frequency band selection approach. The idea of the proposed method is to utilize the information from all the available channels for effectively selecting the most discriminative filter banks. CSP features are extracted from multiple overlapping sub-bands. An additional sub-band has been introduced that cover the wide frequency band (7-30 Hz) and two different types of features are extracted using CSP and common spatio-spectral pattern techniques, respectively. Mutual information is then computed from the extracted features of each of these bands and the top filter banks are selected for further processing. Linear discriminant analysis is applied to the features extracted from each of the filter banks. The scores are fused together, and classification is done using support vector machine. The proposed method is evaluated using BCI Competition III dataset IVa, BCI Competition IV dataset I and BCI Competition IV dataset IIb, and it outperformed all other competing methods achieving the lowest misclassification rate and the highest kappa coefficient on all three datasets. Introducing a wide sub-band and using mutual information for selecting the most discriminative sub-bands, the proposed method shows improvement in motor imagery EEG signal classification.

Residues of selected antibiotics in the South Moravian Rivers, Czech Republic.

PubMed

Jarova, Katerina; Vavrova, Milada; Koleckarova, Alice

2015-01-01

The aim of this study was to assess the contamination level of aquatic ecosystems of the Oslava and the Jihlava Rivers, and of the Nove Mlyny Water Reservoir, situated in the South Moravian Region (Czech Republic), by residues of selected veterinary pharmaceuticals. We isolated and determined 10 sulfonamide antibiotics in samples of surface water and bottom sediments using optimized analytical methods. A representative number of sampling sites in the entire basin of selected waters were chosen. Samples were collected particularly near the larger cities in order to assess their possible impact to the aquatic ecosystems. Extraction, pre-concentration and purification of samples were performed using optimized methods of solid phase extraction and pressurized solvent extraction. Final identification and quantification were carried out by high-performance liquid chromatography coupled with diode array detector. The concentration of sulfonamides in water samples were all under the limit of detection. Regarding sediment samples, sulfadimidine was found at most sampling sites; its highest values were recorded in the Jihlava River (up to 979.8 µg.kg(-1) dry matter). Other frequently detected sulfonamides were sulfamethoxazole and sulfamerazine. Most other sulfonamides were under the limit of detection or limit of quantification. Monitoring of antibiotic residues in the environment, especially in the aquatic ecosystem, is a current topic due to the growing worldwide use in both human and veterinary medicine. According to obtained results, we document the pollution of selected rivers and water reservoir by particular sulfonamides which basically reflects their application in veterinary medicine.

Evaluation of the In Vitro Antiplasmodial, Antileishmanial, and Antitrypanosomal Activity of Medicinal Plants Used in Saudi and Yemeni Traditional Medicine

PubMed Central

Mothana, Ramzi A.; Al-Musayeib, Nawal M.; Al-Ajmi, Mohamed F.; Cos, Paul; Maes, Louis

2014-01-01

The antiplasmodial, antileishmanial, and antitrypanosomal activity of twenty-five medicinal plants distributed in Saudi Arabia and Yemen was evaluated. The plants were extracted with methanol and screened in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi, and free trypomastigotes of T. brucei. To assess selectivity, cytotoxicity was determined on MRC-5 cells. Criteria for activity were an IC50 < 10 μg/mL and high selectivity (SI). Seven plants showed interesting antiprotozoal activity in one or more models. Extracts of Caralluma penicillata and Acalypha ciliata showed fairly good activity against P. falciparum with IC50 of 6.7 and 10.8 μg/mL and adequate selectivity (SI > 9.6 and >5.9). Interesting activity against L. infantum was obtained with Verbascum bottae (IC50 of 3.2 μg/mL, SI 10.2) and Solanum glabratum (IC50 8.1 μg/mL, SI 3.4). The extracts of C. penicillata, Leucas virgata, Loranthus regularis, and V. bottae exhibited moderate activity against T. brucei (IC50 8.5, 8.1, 8.3, and 2.3 μg/mL; SI > 7.6, 7.7, 4.3, and >14.1). These results partly support the traditional use of some of the selected medicinal plants and warrant further investigations into the putative active constituents. PMID:24963330

An effective placental cotyledons proteins extraction method for 2D gel electrophoresis.

PubMed

Tan, Niu J; Daim, Leona D J; Jamil, Amilia A M; Mohtarrudin, Norhafizah; Thilakavathy, Karuppiah

2017-03-01

Effective protein extraction is essential especially in producing a well-resolved proteome on 2D gels. A well-resolved placental cotyledon proteome, with good reproducibility, have allowed researchers to study the proteins underlying the physiology and pathophysiology of pregnancy. The aim of this study is to determine the best protein extraction protocol for the extraction of protein from placental cotyledons tissues for a two-dimensional gel electrophoresis (2D-GE). Based on widely used protein extraction strategies, 12 different extraction methodologies were carefully selected, which included one chemical extraction, two mechanical extraction coupled protein precipitations, and nine chemical extraction coupled protein precipitations. Extracted proteins were resolved in a one-dimensional gel electrophoresis and 2D-GE; then, it was compared with set criteria: extraction efficacy, protein resolution, reproducibility, and recovery efficiency. Our results revealed that a better profile was obtained by chemical extraction in comparison to mechanical extraction. We further compared chemical extraction coupled protein precipitation methodologies, where the DNase/lithium chloride-dense sucrose homogenization coupled dichloromethane-methanol precipitation (DNase/LiCl-DSH-D/MPE) method showed good protein extraction efficiency. This, however, was carried out with the best protein resolution and proteome reproducibility on 2D-gels. DNase/LiCl-DSH-D/MPE was efficient in the extraction of proteins from placental cotyledons tissues. In addition, this methodology could hypothetically allow the protein extraction of any tissue that contains highly abundant lipid and glycogen. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inhibitory activities of selected Sudanese medicinal plants on Porphyromonas gingivalis and matrix metalloproteinase-9 and isolation of bioactive compounds from Combretum hartmannianum (Schweinf) bark.

PubMed

Mohieldin, Ebtihal Abdalla M; Muddathir, Ali Mahmoud; Mitsunaga, Tohru

2017-04-20

Periodontal diseases are one of the major health problems and among the most important preventable global infectious diseases. Porphyromonas gingivalis is an anaerobic Gram-negative bacterium which has been strongly implicated in the etiology of periodontitis. Additionally, matrix metalloproteinases-9 (MMP-9) is an important factor contributing to periodontal tissue destruction by a variety of mechanisms. The purpose of this study was to evaluate the selected Sudanese medicinal plants against P. gingivalis bacteria and their inhibitory activities on MMP-9. Sixty two methanolic and 50% ethanolic extracts from 24 plants species were tested for antibacterial activity against P. gingivalis using microplate dilution assay method to determine the minimum inhibitory concentration (MIC). The inhibitory activity of seven methanol extracts selected from the 62 extracts against MMP-9 was determined by Colorimetric Drug Discovery Kit. In search of bioactive lead compounds, Combretum hartmannianum bark which was found to be within the most active plant extracts was subjected to various chromatographic (medium pressure liquid chromatography, column chromatography on a Sephadex LH-20, preparative high performance liquid chromatography) and spectroscopic methods (liquid chromatography-mass spectrometry, Nuclear Magnetic Resonance (NMR)) to isolate and characterize flavogalonic acid dilactone and terchebulin as bioactive compounds. About 80% of the crude extracts provided a MIC value ≤4 mg/ml against bacteria. The extracts which revealed the highest potency were: methanolic extracts of Terminalia laxiflora (wood; MIC = 0.25 mg/ml) followed by Acacia totrtilis (bark), Ambrosia maritima (aerial part), Argemone mexicana (seed), C. hartmannianum (bark), Terminalia brownii (wood) and 50% ethanolic extract of T. brownii (bark) with MIC values of 0.5 mg/ml. T. laxiflora (wood) and C. hartmannianum (bark) which belong to combretaceae family showed an inhibitory activity over 50% at the concentration of 10 μg/ml against MMP-9. Additionally, MMP-9 was significantly inhibited by terchebulin with IC 50 value of 6.7 μM. To the best of our knowledge, flavogalonic acid dilactone and terchebulin were isolated from C. hartmannianium bark for the first time in this study. Because of terchebulin and some crude extracts acting on P. gingivalis bacteria and MMP-9 enzyme that would make them promising natural preference for preventing and treating periodontal diseases.

Analysis of alternariol and alternariol monomethyl ether in foodstuffs by molecularly imprinted solid-phase extraction and ultra-high-performance liquid chromatography tandem mass spectrometry.

PubMed

Rico-Yuste, A; Walravens, J; Urraca, J L; Abou-Hany, R A G; Descalzo, A B; Orellana, G; Rychlik, M; De Saeger, S; Moreno-Bondi, M C

2018-03-15

Molecularly imprinted porous polymer microspheres selective to Alternaria mycotoxins, alternariol (AOH) and alternariol monomethyl ether (AME), were synthesized and applied to the extraction of both mycotoxins in food samples. The polymer was prepared using 4-vinylpiridine (VIPY) and methacrylamide (MAM) as functional monomers, ethylene glycol dimethacrylate (EDMA) as cross-linker and 3,8,9-trihydroxy-6H-dibenzo[b,d]pyran-6-one (S2) as AOH surrogate template. A molecularly imprinted solid phase extraction (MISPE) method has been optimized for the selective isolation of the mycotoxins from aqueous samples coupled to HPLC with fluorescence (λ ex =258nm; λ em =440nm) or MS/MS analysis. The MISPE method was validated by UPLC-MS/MS for the determination of AOH and AME in tomato juice and sesame oil based on the European Commission Decision 2002/657/EC. Method performance was satisfactory with recoveries from 92.5% to 106.2% and limits of quantification within the 1.1-2.8µgkg -1 range in both samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiresidue analysis of multiclass pesticides and polyaromatic hydrocarbons in fatty fish by gas chromatography tandem mass spectrometry and evaluation of matrix effect.

PubMed

Chatterjee, Niladri S; Utture, Sagar; Banerjee, Kaushik; Ahammed Shabeer, T P; Kamble, Narayan; Mathew, Suseela; Ashok Kumar, K

2016-04-01

This paper reports a selective and sensitive method for multiresidue determination of 119 chemical residues including pesticides and polyaromatic hydrocarbons (PAH) in high fatty fish matrix. The novel sample preparation method involved extraction of the target analytes from homogenized fish meat (5 g) in acetonitrile (15 mL, 1% acetic acid) after three-phase partitioning with hexane (2 mL) and the remaining aqueous layer. An aliquot (1.5 mL) of the acetonitrile layer was aspirated and subjected to two-stage dispersive solid phase extraction (dSPE) cleanup and the residues were finally estimated by gas chromatography mass spectrometry with selected reaction monitoring (GC-MS/MS). The co-eluted matrix components were identified on the basis of their accurate mass by GC with quadrupole time of flight MS. Addition of hexane during extraction and optimized dSPE cleanup significantly minimized the matrix effects. Recoveries at 10, 25 and 50 μg/kg were within 60-120% with associated precision, RSD<11%. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coupling alkaline pre-extraction with alkaline-oxidative post-treatment of corn stover to enhance enzymatic hydrolysis and fermentability.

PubMed

Liu, Tongjun; Williams, Daniel L; Pattathil, Sivakumar; Li, Muyang; Hahn, Michael G; Hodge, David B

2014-04-03

A two-stage chemical pretreatment of corn stover is investigated comprising an NaOH pre-extraction followed by an alkaline hydrogen peroxide (AHP) post-treatment. We propose that conventional one-stage AHP pretreatment can be improved using alkaline pre-extraction, which requires significantly less H2O2 and NaOH. To better understand the potential of this approach, this study investigates several components of this process including alkaline pre-extraction, alkaline and alkaline-oxidative post-treatment, fermentation, and the composition of alkali extracts. Mild NaOH pre-extraction of corn stover uses less than 0.1 g NaOH per g corn stover at 80°C. The resulting substrates were highly digestible by cellulolytic enzymes at relatively low enzyme loadings and had a strong susceptibility to drying-induced hydrolysis yield losses. Alkaline pre-extraction was highly selective for lignin removal over xylan removal; xylan removal was relatively minimal (~20%). During alkaline pre-extraction, up to 0.10 g of alkali was consumed per g of corn stover. AHP post-treatment at low oxidant loading (25 mg H2O2 per g pre-extracted biomass) increased glucose hydrolysis yields by 5%, which approached near-theoretical yields. ELISA screening of alkali pre-extraction liquors and the AHP post-treatment liquors demonstrated that xyloglucan and β-glucans likely remained tightly bound in the biomass whereas the majority of the soluble polymeric xylans were glucurono (arabino) xylans and potentially homoxylans. Pectic polysaccharides were depleted in the AHP post-treatment liquor relative to the alkaline pre-extraction liquor. Because the already-low inhibitor content was further decreased in the alkaline pre-extraction, the hydrolysates generated by this two-stage pretreatment were highly fermentable by Saccharomyces cerevisiae strains that were metabolically engineered and evolved for xylose fermentation. This work demonstrates that this two-stage pretreatment process is well suited for converting lignocellulose to fermentable sugars and biofuels, such as ethanol. This approach achieved high enzymatic sugars yields from pretreated corn stover using substantially lower oxidant loadings than have been reported previously in the literature. This pretreatment approach allows for many possible process configurations involving novel alkali recovery approaches and novel uses of alkaline pre-extraction liquors. Further work is required to identify the most economical configuration, including process designs using techno-economic analysis and investigating processing strategies that economize water use.

Nootropic activity of lipid-based extract of Bacopa monniera Linn. compared with traditional preparation and extracts.

PubMed

Lohidasan, Sathiyanarayanan; Paradkar, Anant R; Mahadik, Kakasaheb R

2009-11-01

The aim was to design an alternative solvent-free extraction method using the hydrophilic lipid Gelucire (polyethylene glycol glycerides) for herbal extraction and to confirm the efficacy of extraction using biological screening. Bacopa monniera Linn. (BM) was selected for the study. Conventional methanolic extract (MEBM), Ayurvedic ghrita (AGBM) and lipid extracts (LEBM) were prepared and standardised by high-performance thin-layer chromatography (HPTLC). Nootropic activity in rats was evaluated using the two-trial Y-maze test and the anterograde amnesia induced by scopolamine (1 mg/kg i.p.) determined by the conditioned avoidance response. The extracts were administered daily at doses of 100, 200 and 400 mg/kg orally. At the end of the conditioned avoidance response test, brain monoamine levels were estimated by HPLC. The LEBM, MEBM and AGBM contained 3.56%, 4.10% and 0.005% bacoside A, respectively. Significantly greater spatial recognition was observed with LEBM (P < 0.001 at 400 and 200 mg/kg) and MEBM (P < 0.001 at 400 mg/kg, P < 0.01 at 200 mg/kg) than AGBM. The conditioned avoidance response was significantly higher in the groups treated with high doses of LEBM and MEBM than AGBM. There were significant decreases in brain noradrenaline (P < 0.001) and 5-hydroxytryptamine (P < 0.01) levels and an increase in dopamine levels (P < 0.05) in the LEBM-treated groups compared with the stress control group. The proposed LEBM is solvent free, does not have the shortcomings associated with conventional extraction, and had comparable nootropic activity to the MEBM.

Improved selectivity for high-performance liquid chromatographic determination of clonazepam in plasma of epileptic patients.

PubMed

Le Guellec, C; Gaudet, M L; Breteau, M

1998-11-20

We report a high-performance liquid chromatography method for clonazepam determination in plasma. The use of a synthetic silica-based stationary phase markedly improved clonazepam resolution compared to standard reversed-phase columns. A liquid-liquid extraction was used, associated with reversed-phase chromatography, gradient elution and ultraviolet detection. Accuracy and precision were satisfactory at therapeutic concentrations. Selectivity was studied for benzodiazepines or other antiepileptic drugs, with particular attention to newly marketed drugs i.e., gabapentine and vigabatrin. No interfering substance was evidenced. Under the conditions described, it was possible to quantify clonazepam at nanogram level even when carbamazepine was present at therapeutic concentrations.

Hydride Generation for Headspace Solid-Phase Extraction with CdTe Quantum Dots Immobilized on Paper for Sensitive Visual Detection of Selenium.

PubMed

Huang, Ke; Xu, Kailai; Zhu, Wei; Yang, Lu; Hou, Xiandeng; Zheng, Chengbin

2016-01-05

A low-cost, simple, and highly selective analytical method was developed for sensitive visual detection of selenium in human urine both outdoors and at home, by coupling hydride generation with headspace solid-phase extraction using quantum dots (QDs) immobilized on paper. The visible fluorescence from the CdTe QDs immobilized on paper was quenched by H2Se from hydride generation reaction and headspace solid-phase extraction. The potential mechanism was investigated by using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) as well as Density Functional Theory (DFT). Potential interferences from coexisting ions, particularly Ag(+), Cu(2+), and Zn(2+), were eliminated. The selectivity was significantly increased because the selenium hydride was effectively separated from sample matrices by hydride generation. Moreover, due to the high sampling efficiency of hydride generation and headspace solid phase extraction, the sensitivity and the limit of detection (LOD) were significantly improved compared to conventional methods. A LOD of 0.1 μg L(-1) and a relative standard deviation (RSD, n = 7) of 2.4% at a concentration of 20 μg L(-1) were obtained when using a commercial spectrofluorometer as the detector. Furthermore, a visual assay based on the proposed method was developed for the detection of Se, 5 μg L(-1) of selenium in urine can be discriminated from the blank solution with the naked eye. The proposed method was validated by analysis of certified reference materials and human urine samples with satisfactory results.

Extraction of maxillary canines: Esthetic perceptions of patient smiles among dental professionals and laypeople.

PubMed

Thiruvenkatachari, Badri; Javidi, Hanieh; Griffiths, Sarah Elizabeth; Shah, Anwar A; Sandler, Jonathan

2017-10-01

Maxillary canines are generally considered important both cosmetically and functionally. Most claims on the importance of maxillary canines, however, have been based on expert opinions and clinician-based studies. There are no scientific studies in the literature reporting on their cosmetic importance or how laypeople perceive a smile treated by maxillary canine extractions. Our objective was to investigate whether there is any difference in the perceptions of patients' smiles treated by extracting either maxillary canines or first premolars, as judged by orthodontists, dentists, and laypeople. This retrospective study included 24 participants who had unilateral or bilateral extraction of maxillary permanent canines and fixed appliances in the maxillary and mandibular arches to comprehensively correct the malocclusion, selected from orthodontic patients treated at Chesterfield Royal Hospital NHS trust in the United Kingdom over the last 20 years. The control group of patients had extraction of maxillary first premolars followed by fixed appliances and finished to an extremely high standard judged by the requirement that they had been submitted for the Membership in Orthodontics examination. The finished Peer Assessment Rating scores for this group were less than 5. The end-of-treatment frontal extraoral smiling and frontal intraoral views were presented for both groups. The photographs were blinded for extraction choice and standardized for size and brightness using computer software (Adobe Photoshop CC version 14.0; Adobe Systems, San Jose, Calif). The work file was converted to an editable pdf file and e-mailed to the assessors. The assessor panel consisted of 30 members (10 orthodontists, 10 dentists, and 10 laypeople), who were purposely selected. The measures were rated on a 10-point Likert scale. The attractiveness ratings were not statistically significantly different between the canine extraction and premolar extraction groups, with a mean difference of 0.33 (SD, 0.29) points. A 1-way repeated-measures analysis of variance to test the difference in scores among the laypeople, orthodontists, and dentists (n = 30) showed no statistically significant difference (Wilks lambda = 0.835; P = 0.138), and the Bonferroni test indicated that no pair-wise difference was statistically significant. No statistically significant difference was found in the smile attractiveness between canine extraction and premolar extraction patients as assessed by general dentists, laypeople, and orthodontists. Further high-quality studies are required to evaluate the effect of canine extraction and premolar substitution on functional occlusion. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Immunoglobulin E antibodies to pollens augmented in dogs by virus vaccines.

PubMed

Frick, O L; Brooks, D L

1983-03-01

An inbred "atopic dog colony" was established to study the effect of viruses on immunoregulation of immunoglobulin (Ig) E antibodies. Dogs were selected for high skin reactivity to grass and weed pollens. Their offspring were inoculated with pollen extracts in alum immediately after routine vaccinations (attenuated live-virus vaccines for canine distemper and infectious canine hepatitis, and a killed bacterin for Leptospira). Heat labile antipollen IgE antibodies were measured by passive cutaneous anaphylaxis. Pups vaccinated for canine distemper before being given pollen extracts had many more IgE antibodies than did their control littermates who were not vaccinated until after the last pollen extract injection. This may be a natural example of the "allergic break-through phenomenon."

Antioxidant and anti-inflammatory activities of selected medicinal plants and fungi containing phenolic and flavonoid compounds

PubMed Central

2012-01-01

Background This study aims to determine the relationship between the antioxidant and anti-inflammatory activities of the thirteen herbs and two fungi extracts, and their total phenolic and flavonoid contents. Methods Antioxidant activities were evaluated by four assays: an antioxidant activity assay using Saccharomyces cerevisiae, a DPPH ((2, 2-diphenyl-1-picrylhydrazyl) assay to assess free radical scavenging, an assay assessing ferrous ions or iron (II) chelating ability, and a ferric reducing antioxidant power (FRAP) assay. Total phenolic and flavonoid contents were determined using the Folin-Ciocalteu and aluminium chloride methods, respectively. Anti-inflammatory activities were determined by measuring the inhibition of nitric oxide and TNF-α production in lipopolysaccharide- and interferon-γ-activated J774A.1 macrophages. Their cytotoxicities against macrophages were determined by MTT assay. Results A positive linear correlation between antioxidant activities and the total phenolic and flavonoid content of the plant extracts was found. The plant extracts with high phenolic and flavonoid content also exhibited significant anti-inflammatory activity with good cell viability. Conclusion The selected herbs could be a rich source of antioxidants and free radical scavenging compounds. The levels of phenolic and flavonoid compounds were correlated with the antioxidant and anti-inflammatory activities of the extracts from the herbs. PMID:23176585

Antioxidant and anti-inflammatory activities of selected medicinal plants and fungi containing phenolic and flavonoid compounds.

PubMed

Diaz, Patricia; Jeong, Sang Chul; Lee, Samiuela; Khoo, Cheang; Koyyalamudi, Sundar Rao

2012-11-24

This study aims to determine the relationship between the antioxidant and anti-inflammatory activities of the thirteen herbs and two fungi extracts, and their total phenolic and flavonoid contents. Antioxidant activities were evaluated by four assays: an antioxidant activity assay using Saccharomyces cerevisiae, a DPPH ((2, 2-diphenyl-1-picrylhydrazyl) assay to assess free radical scavenging, an assay assessing ferrous ions or iron (II) chelating ability, and a ferric reducing antioxidant power (FRAP) assay. Total phenolic and flavonoid contents were determined using the Folin-Ciocalteu and aluminium chloride methods, respectively. Anti-inflammatory activities were determined by measuring the inhibition of nitric oxide and TNF-α production in lipopolysaccharide- and interferon-γ-activated J774A.1 macrophages. Their cytotoxicities against macrophages were determined by MTT assay. A positive linear correlation between antioxidant activities and the total phenolic and flavonoid content of the plant extracts was found. The plant extracts with high phenolic and flavonoid content also exhibited significant anti-inflammatory activity with good cell viability. The selected herbs could be a rich source of antioxidants and free radical scavenging compounds. The levels of phenolic and flavonoid compounds were correlated with the antioxidant and anti-inflammatory activities of the extracts from the herbs.

Characterising Tidal Flow Within AN Energetic Tidal Environment

NASA Astrophysics Data System (ADS)

Neill, S. P.; Goward Brown, A.; Lewis, M. J.

2016-02-01

The Pentland Firth is a highly energetic and complex tidal strait separating the north of Scotland with the Orkney Islands and is a key location for tidal energy exploitation. Topographic features including islands and headlands, combined with bathymetric complexities within the Pentland Firth create turbulent hydrodynamic flows which are difficult to observe. Site selection in tidal energy environments historically focuses on tidal current magnitude. Without consideration for the more complex hydrodynamics of tidal energy environments tidal energy developers may miss the opportunity to tune their devices or create environment specific tidal energy converters in order to harness the greatest potential from site. Fully characterising these tidal energy environments ensures economic energy extraction. Understanding the interaction of energy extraction with the environment will reduce uncertainty in site selection and allow mitigation of any potential environmental concerns. We apply the 3D ROMS model to the Pentland Firth with the aim of resolving uncertainties within tidal energy resource assessment. Flow magnitudes and directions are examined with a focus on tidal phasing and asymmetry and application to sediment dynamics. Using the ROMS model, it is possible to determine the extent to which the tidal resource varies temporally and spatially with tidal energy extraction. Accurately modelling the tidal dynamics within this environment ensures that potential consequences of tidal energy extraction on the surrounding environment are better understood.

Selective solid-phase extraction based on molecularly imprinted technology for the simultaneous determination of 20 triazole pesticides in cucumber samples using high-performance liquid chromatography-tandem mass spectrometry.

PubMed

Zhao, Fengnian; She, Yongxin; Zhang, Chao; Cao, Xiaolin; Wang, Shanshan; Zheng, Lufei; Jin, Maojun; Shao, Hua; Jin, Fen; Wang, Jing

2017-10-01

A selective analytical method for the simultaneous determination of 20 triazole fungicides and plant growth regulators in cucumber samples was developed using solid-phase extraction with specific molecularly imprinted polymers (MIPs) as adsorbents. The MIPs were successfully prepared by precipitation polymerization using triadimefon as the template molecule, methacrylic acid as the functional monomer, trimethylolpropane trimethacrylate as the crosslinker, and acetonitrile as the porogen. The performance and recognition mechanism for both the MIPs and non-molecularly imprinted polymers were evaluated using adsorption isotherms and adsorption kinetics. Liquid chromatography-tandem quadrupole mass spectrometry was used to identify and quantify the target analytes. The solid-phase extraction using the MIPs was rapid, convenient, and efficient for extraction and enrichment of the 20 triazole pesticides from cucumber samples. The recoveries obtained at three concentration levels (1, 2, and 10μgL -1 ) ranged from 82.3% to 117.6% with relative standard deviations of less than 11.8% (n=5) for all analytes. The limits of detection for the 20 triazole pesticides were all less than 0.4μgL -1 , and were sufficient to meet international standards. Copyright © 2017 Elsevier B.V. All rights reserved.

HPLC-ED Analysis of Phenolic Compounds in Three Bosnian Crataegus Species.

PubMed

Čulum, Dušan; Čopra-Janićijević, Amira; Vidic, Danijela; Klepo, Lejla; Tahirović, Azra; Bašić, Neđad; Maksimović, Milka

2018-04-24

The aim of this work was the qualitative and quantitative determination of selected phenolic compounds in three Crataegus species grown in Bosnia. Crataegus plants are consumed for medicinal purposes and as foodstuff in the form of canned fruit, jam, jelly, tea, and wine. Two samples of plant material, dry leaves with flowers, and berries of three Crataegus species— Crataegus rhipidophylla Gand., Crataegus x subsphaericea Gand., and Crataegus x macrocarpa Hegetschw.—were analyzed. Twelve ethanolic extracts were isolated from the selected plant material using Soxhlet and ultrasound extraction, respectively. Soxhlet extraction proved to be more effective than ultrasound extraction. A simple and sensitive method, high-performance liquid chromatography with electrochemical detection, HPLC-ED, was used for the simultaneous determination of phenolic acids and flavonoids in Crataegus species. The content of gallic acid in the extracts ranged from 0.001 to 0.082 mg/g dry weight (DW), chlorogenic acid from 0.19 to 8.70 mg/g DW, and rutin from 0.03 to 13.49 mg/g DW. Two flavonoids, vitexin and hyperoside, commonly found in chemotaxonomic investigations of Crataegus species, were not detected in the examined extracts. In general, leaves with flowers samples are richer in gallic acid and rutin, whereas the berries samples are richer in chlorogenic acid. Distinct similarities were found in the relative distribution of gallic acid among the three species. Extracts of C. x macrocarpa had the highest content of all detected compounds, while significant differences were found in rutin content, depending on the plant organ. To the best of our knowledge, this is the first study reporting content of phenolic compounds in Crataegus rhipidophylla Gand., Crataegus x subsphaericea , and Crataegus x macrocarpa from Bosnia.

HPLC-ED Analysis of Phenolic Compounds in Three Bosnian Crataegus Species

PubMed Central

Čulum, Dušan; Vidic, Danijela; Klepo, Lejla; Tahirović, Azra; Bašić, Neđad; Maksimović, Milka

2018-01-01

The aim of this work was the qualitative and quantitative determination of selected phenolic compounds in three Crataegus species grown in Bosnia. Crataegus plants are consumed for medicinal purposes and as foodstuff in the form of canned fruit, jam, jelly, tea, and wine. Two samples of plant material, dry leaves with flowers, and berries of three Crataegus species—Crataegus rhipidophylla Gand., Crataegus x subsphaericea Gand., and Crataegus x macrocarpa Hegetschw.—were analyzed. Twelve ethanolic extracts were isolated from the selected plant material using Soxhlet and ultrasound extraction, respectively. Soxhlet extraction proved to be more effective than ultrasound extraction. A simple and sensitive method, high-performance liquid chromatography with electrochemical detection, HPLC-ED, was used for the simultaneous determination of phenolic acids and flavonoids in Crataegus species. The content of gallic acid in the extracts ranged from 0.001 to 0.082 mg/g dry weight (DW), chlorogenic acid from 0.19 to 8.70 mg/g DW, and rutin from 0.03 to 13.49 mg/g DW. Two flavonoids, vitexin and hyperoside, commonly found in chemotaxonomic investigations of Crataegus species, were not detected in the examined extracts. In general, leaves with flowers samples are richer in gallic acid and rutin, whereas the berries samples are richer in chlorogenic acid. Distinct similarities were found in the relative distribution of gallic acid among the three species. Extracts of C. x macrocarpa had the highest content of all detected compounds, while significant differences were found in rutin content, depending on the plant organ. To the best of our knowledge, this is the first study reporting content of phenolic compounds in Crataegus rhipidophylla Gand., Crataegus x subsphaericea, and Crataegus x macrocarpa from Bosnia. PMID:29695058

Application of an aqueous two-phase micellar system to extract bromelain from pineapple (Ananas comosus) peel waste and analysis of bromelain stability in cosmetic formulations.

PubMed

Spir, Lívia Genovez; Ataide, Janaína Artem; De Lencastre Novaes, Letícia Celia; Moriel, Patrícia; Mazzola, Priscila Gava; De Borba Gurpilhares, Daniela; Silveira, Edgar; Pessoa, Adalberto; Tambourgi, Elias Basile

2015-01-01

Bromelain is a set of proteolytic enzymes found in pineapple (Ananas comosus) tissues such as stem, fruit and leaves. Because of its proteolytic activity, bromelain has potential applications in the cosmetic, pharmaceutical, and food industries. The present study focused on the recovery of bromelain from pineapple peel by liquid-liquid extraction in aqueous two-phase micellar systems (ATPMS), using Triton X-114 (TX-114) and McIlvaine buffer, in the absence and presence of electrolytes CaCl2 and KI; the cloud points of the generated extraction systems were studied by plotting binodal curves. Based on the cloud points, three temperatures were selected for extraction: 30, 33, and 36°C for systems in the absence of salts; 40, 43, and 46°C in the presence of KI; 24, 27, and 30°C in the presence of CaCl2 . Total protein and enzymatic activities were analyzed to monitor bromelain. Employing the ATPMS chosen for extraction (0.5 M KI with 3% TX-114, at pH 6.0, at 40°C), the bromelain extract stability was assessed after incorporation into three cosmetic bases: an anhydrous gel, a cream, and a cream-gel formulation. The cream-gel formulation presented as the most appropriate base to convey bromelain, and its optimal storage conditions were found to be 4.0 ± 0.5°C. The selected ATPMS enabled the extraction of a biomolecule with high added value from waste lined-up in a cosmetic formulation, allowing for exploration of further cosmetic potential. © 2015 American Institute of Chemical Engineers.

High-performance liquid chromatographic determination of the beta2-selective adrenergic agonist fenoterol in human plasma after fluorescence derivatization.

PubMed

Kramer, S; Blaschke, G

2001-02-10

A sensitive high-performance liquid chromatographic method has been developed for the determination of the beta2-selective adrenergic agonist fenoterol in human plasma. To improve the sensitivity of the method, fenoterol was derivatized with N-(chloroformyl)-carbazole prior to HPLC analysis yielding highly fluorescent derivatives. The assay involves protein precipitation with acetonitrile, liquid-liquid-extraction of fenoterol from plasma with isobutanol under alkaline conditions followed by derivatization with N-(chloroformyl)-carbazole. Reversed-phase liquid chromatographic determination of the fenoterol derivative was performed using a column-switching system consisting of a LiChrospher 100 RP 18 and a LiChrospher RP-Select B column with acetonitrile, methanol and water as mobile phase. The limit of quantitation in human plasma was 376 pg fenoterol/ml. The method was successfully applied for the assay of fenoterol in patient plasma.

Tracing Asian Seabass Individuals to Single Fish Farms Using Microsatellites

PubMed Central

Yue, Gen Hua; Xia, Jun Hong; Liu, Peng; Liu, Feng; Sun, Fei; Lin, Grace

2012-01-01

Traceability through physical labels is well established, but it is not highly reliable as physical labels can be easily changed or lost. Application of DNA markers to the traceability of food plays an increasingly important role for consumer protection and confidence building. In this study, we tested the efficiency of 16 polymorphic microsatellites and their combinations for tracing 368 fish to four populations where they originated. Using the maximum likelihood and Bayesian methods, three most efficient microsatellites were required to assign over 95% of fish to the correct populations. Selection of markers based on the assignment score estimated with the software WHICHLOCI was most effective in choosing markers for individual assignment, followed by the selection based on the allele number of individual markers. By combining rapid DNA extraction, and high-throughput genotyping of selected microsatellites, it is possible to conduct routine genetic traceability with high accuracy in Asian seabass. PMID:23285169

Detection of biomarkers for Hepatocellular Carcinoma using a hybrid univariate gene selection methods

PubMed Central

2012-01-01

Background Discovering new biomarkers has a great role in improving early diagnosis of Hepatocellular carcinoma (HCC). The experimental determination of biomarkers needs a lot of time and money. This motivates this work to use in-silico prediction of biomarkers to reduce the number of experiments required for detecting new ones. This is achieved by extracting the most representative genes in microarrays of HCC. Results In this work, we provide a method for extracting the differential expressed genes, up regulated ones, that can be considered candidate biomarkers in high throughput microarrays of HCC. We examine the power of several gene selection methods (such as Pearson’s correlation coefficient, Cosine coefficient, Euclidean distance, Mutual information and Entropy with different estimators) in selecting informative genes. A biological interpretation of the highly ranked genes is done using KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, ENTREZ and DAVID (Database for Annotation, Visualization, and Integrated Discovery) databases. The top ten genes selected using Pearson’s correlation coefficient and Cosine coefficient contained six genes that have been implicated in cancer (often multiple cancers) genesis in previous studies. A fewer number of genes were obtained by the other methods (4 genes using Mutual information, 3genes using Euclidean distance and only one gene using Entropy). A better result was obtained by the utilization of a hybrid approach based on intersecting the highly ranked genes in the output of all investigated methods. This hybrid combination yielded seven genes (2 genes for HCC and 5 genes in different types of cancer) in the top ten genes of the list of intersected genes. Conclusions To strengthen the effectiveness of the univariate selection methods, we propose a hybrid approach by intersecting several of these methods in a cascaded manner. This approach surpasses all of univariate selection methods when used individually according to biological interpretation and the examination of gene expression signal profiles. PMID:22867264

[Study on extraction process of available components of tea].

PubMed

Bai, Qing-Qing; Liu, Yong-Feng; Guo, Mei; Zhao, Jian-Xi; Zhang, Tian-Cai; Di, Duo-Long

2011-09-01

To investigate the optimum ethanol extraction process conditions for the available components in the tea - Catechines (CT) including Epigallo catechin gallate (EGCG) and Caffeine (CF). The content of EGCG, CT and CF, extraction rate, DPPH * Free radical scavenging capacity were chosen as the assessment indexes. With the alcohol ratio (A), solid-liquid ratio (B) and reflux time (C) as investigation factors, the optimum ethanol extraction process of the available components from tea was determined by L9 (3(4)) orthogonal experimental design. It would obtain different extraction conditions to analyze the assessment indexes depending on the different extraction purposes. For the purpose of CT, the contents of EGCG and CT, extraction rate and DPPH * Free radical scavenging capacity were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 75% alcohol was 1: 12, the reflux time was 30 minutes and extraction times were three; For the purpose of CF, the content of CF and extraction rate were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 60% alcohol was 1: 12, the reflux time was 30 minutes and extraction times were three; For the purpose of integrated extraction, the contents of CT and CF, extraction rate and DPPH * Free radical scavenging capacity were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 60% alcohol was 1: 8, the reflux time was 30 minutes and extraction times were three. The optimum extraction process in order to attain different purposes can give a reference to the research of a new medicine and industry production.

Selective extraction of bisphenol A from water by one-monomer molecularly imprinted magnetic nanoparticles.

PubMed

Lin, Zhenkun; Zhang, Yanfang; Su, Yu; Qi, Jinxia; Jia, Yinhang; Huang, Changjiang; Dong, Qiaoxiang

2018-01-15

One-monomer molecularly imprinted magnetic nanoparticles were prepared as adsorbents for selective extraction of bisphenol A from water in this study. A single bi-functional monomer was adopted for preparation of the molecularly imprinted polymer, avoiding the tedious trial-and-error optimizations as traditional strategy. Moreover, bisphenol F was used as the dummy template for bisphenol A to avoid the interference from residual template molecules. These nanoparticles showed not only large adsorption capacity and good selectivity to the bisphenol A but also outstanding magnetic response performance. Furthermore, they were successfully used as magnetic solid-phase extraction adsorbents of bisphenol A from various water samples, including tap water, river water, and seawater. The developed method was found to be much more efficient, convenient, and economical for selective extraction of bisphenol A compared with the traditional solid-phase extraction. Separation of these nanoparticles can be easily achieved with an external magnetic field, and the optimized adsorption time was only 15 min. The recoveries of bisphenol A in different water samples ranged from 85.38 to 93.75%, with relative standard deviation lower than 7.47%. These results showed that one-monomer molecularly imprinted magnetic nanoparticles had the potential to be popular adsorbents for selective extraction of pollutants from water. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.