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Sample records for assisted sequential extraction

  1. Speciation of heavy metals in untreated sewage sludge by using microwave assisted sequential extraction procedure

    International Nuclear Information System (INIS)

    A fast microwave assisted extraction procedure was developed and optimized for their eventual exploitation in the three-stage sequential extraction procedure proposed by modified BCR protocol (the community Bureau of Reference now the European Union 'Measurement and Testing Programme'). The effects of the microwave treatment on the extraction of Cd, Cr, Cu, Ni, Pb and Zn from untreated sewage sludge collected from Hyderabad city (Pakistan) were compared with those obtained from sequential BCR extraction procedure. In sequential BCR method, each extraction step takes 16 h, where as with the use of compromised microwave conditions, extraction steps could be completed in about 120 s, for each step, respectively. Extractable Cd, Cr, Pb and Ni obtained by both comparable methodologies were measured by electrothermal atomic absorption spectrometry (ETAAS), while for Cu and Zn flame atomic absorption spectrometry (FAAS) was used. The validations of both extraction techniques were compared by the analysis of certified reference material of soil amended with sewage sludge (BCR 483). The results of the partitioning study of untreated waste water sewage sludge, indicate that more easily mobilized forms (step 1) were predominant for Cd, Ni and Zn (28.3, 28.4 and 43.7%), in contrast, the largest amount of Cd and Pb (66.4 and 72.8%) was associated with the iron/manganese oxide while Cr and Ni (71.2 and 38.7%) in organic matter/sulphide fractions. The overall metal recoveries in steps 1-3 (excluding residual step) were 95.3-104% of those obtained with the sequential BCR protocol. The accuracy of the proposed microwave extraction method (expressed as %R.S.D.) was lower than 10% for all metals

  2. Instant controlled pressure drop technology and ultrasound assisted extraction for sequential extraction of essential oil and antioxidants.

    Science.gov (United States)

    Allaf, Tamara; Tomao, Valérie; Ruiz, Karine; Chemat, Farid

    2013-01-01

    The instant controlled pressure drop (DIC) technology enabled both the extraction of essential oil and the expansion of the matrix itself which improved solvent extraction. The sequential use of DIC and Ultrasound Assisted Extraction (UAE) triggered complementary actions materialized by supplementary effects. We visualized these combination impacts by comparing them to standard techniques: Hydrodistillation (HD) and Solvent Extraction (SE). First, the extraction of orange peel Essential Oils (EO) was achieved by HD during 4h and DIC process (after optimization) during 2 min; EO yields was 1.97 mg/g dry material (dm) with HD compared to 16.57 mg/g d m with DIC. Second, the solid residue was recovered to extract antioxidant compounds (naringin and hesperidin) by SE and UAE. Scanning electron microscope showed that after HD the recovered solid shriveled as opposite to DIC treatment which expanded the product structure. HPLC analyses showed that the best kinetics and yields of naringin and hesperidin extraction was when DIC and UAE are combined. Indeed, after 1h of extraction, DIC treated orange peels with UAE were 0.825 ± 1.6 × 10(-2)g/g of dry material (dm) for hesperidin and 6.45 × 10(-2) ± 2.3 × 10(-4)g/g d m for naringin compared to 0.64 ± 2.7 × 10(-2)g/g of dry material (dm) and 5.7 × 10(-2) ± 1.6 × 10(-3)g/g d m, respectively with SE. By combining DIC to UAE, it was possible to enhance kinetics and yields of antioxidant extraction.

  3. Sequential microwave-assisted extraction of oil from layer poultry feeds and GC-MS quantification of the fatty acids

    International Nuclear Information System (INIS)

    The present study reports the effect of sequential microwave-assisted extraction (SeMAE) on fatty acids composition (FAC) of layer poultry feed oil as compared to conventional Soxhlet extraction (SE) method. The FAC of extracted oil was determined by gas chromatography - mass spectrometry (GC-MS). There was no significant difference found in the amount of total extracted oil and FAC by SeMAE and SE. However, slightly greater content of trans fat in the samples revealed that SE lead to the formation of a little higher level of trans fat as compare to SeMAE. Therefore, the SeMAE could be used as a remarkable substitute to conventional SE for extraction of oil from the poultry feeds due to its faster speed, lesser solvent consumption, more environmental friendly. (author)

  4. Speciation of heavy metals in sediment by conventional, ultrasound and microwave assisted single extraction methods: A comparison with modified sequential extraction procedure

    International Nuclear Information System (INIS)

    Sequential extraction procedure proposed by the European Standards, Measurements and Testing (SM and T) Program, formerly the Community Bureau of Reference (BCR), has been applied for the heavy metals (HMs) partitioning in fresh water lake sediment samples. The results obtained by conventional sequential extraction BCR method (SEB) for Cd, Cu, Cr, Ni, Pb and Zn were compared with those estimated from three alternative single extractions, conventional (CSE), ultrasonic (USE) and microwave assisted (MSE), using identical operating conditions applied in each individual BCR fraction and validated by the CRM BCR 701. Extractable HMs contents obtained by all compared methodologies were measured by atomic absorption spectrometery. With the use of compromised sonication and microwave conditions, steps 1-3 of the sequential extraction (excluding the hydrogen peroxide digestion in step 3) could be completed between 15-30 min using ultrasonic bath, while 60-120 s were required for MSE. The total extractable metal contents obtained by three single extractions ranged from 75.1% to 114.0% except Cr in first step, which was extracted (125.3%) by MSE method as compared to those obtained by SEB procedure. The precision of the proposed BCR single extraction methods (expressed as RSD%) was found in the range of (3.99-9.6%) for all metals

  5. Fractionation of trace elements in agricultural soils using ultrasound assisted sequential extraction prior to inductively coupled plasma mass spectrometric determination.

    Science.gov (United States)

    Matong, Joseph M; Nyaba, Luthando; Nomngongo, Philiswa N

    2016-07-01

    The main objectives of this study were to determine the concentration of fourteen trace elements and to investigate their distribution as well as a contamination levels in selected agricultural soils. An ultrasonic assisted sequential extraction procedure derived from three-step BCR method was used for fractionation of trace elements. The total concentration of trace elements in soil samples was obtained by total digestion method in soil samples with aqua regia. The results of the extractable fractions revealed that most of the target trace elements can be transferred to the human being through the food chain, thus leading to serious human health. Enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF), risk assessment code (RAC) and individual contamination factors (ICF) were used to assess the environmental impacts of trace metals in soil samples. The EF revealed that Cd was enriched by 3.1-7.2 (except in Soil 1). The Igeo results showed that the soils in the study area was moderately contaminated with Fe, and heavily to extremely polluted with Cd. The soil samples from the unplanted field was found to have highest contamination factor for Cd and lowest for Pb. Soil 3 showed a high risk for Tl and Cd with RAC values of greater than or equal to 50%. In addition, Fe, Ni, Cu, V, As, Mo (except Soil 2), Sb and Pb posed low environmental risk. The modified BCR sequential extraction method provided more information about mobility and environmental implication of studied trace elements in the study area. PMID:27058917

  6. Fast determination of trace elements in organic fertilizers using a cup-horn reactor for ultrasound-assisted extraction and fast sequential flame atomic absorption spectrometry.

    Science.gov (United States)

    Teixeira, Leonel Silva; Vieira, Heulla Pereira; Windmöller, Cláudia Carvalhinho; Nascentes, Clésia Cristina

    2014-02-01

    A fast and accurate method based on ultrasound-assisted extraction in a cup-horn sonoreactor was developed to determine the total content of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in organic fertilizers by fast sequential flame atomic absorption spectrometry (FS FAAS). Multivariate optimization was used to establish the optimal conditions for the extraction procedure. An aliquot containing approximately 120 mg of the sample was added to a 500 µL volume of an acid mixture (HNO3/HCl/HF, 5:3:3, v/v/v). After a few minutes, 500 µL of deionized water was added and eight samples were simultaneously sonicated for 10 min at 50% amplitude, allowing a sample throughput of 32 extractions per hour. The performance of the method was evaluated with a certified reference material of sewage sludge (CRM 029). The precision, expressed as the relative standard deviation, ranged from 0.58% to 5.6%. The recoveries of analytes were found to 100%, 109%, 96%, 92%, 101%, 104% and 102% for Cd, Cr, Cu, Mn, Ni, Pb and Zn, respectively. The linearity, limit of detection and limit of quantification were calculated and the values obtained were adequate for the quality control of organic fertilizers. The method was applied to the analysis of several commercial organic fertilizers and organic wastes used as fertilizers, and the results were compared with those obtained using the microwave digestion procedure. A good agreement was found between the results obtained by microwave and ultrasound procedures with recoveries ranging from 80.4% to 117%. Two organic waste samples were not in accordance with the Brazilian legislation regarding the acceptable levels of contaminants.

  7. Sequential extraction of uranium metal contamination

    International Nuclear Information System (INIS)

    Samples of uranium contaminated dirt collected from the dirt floor of an abandoned metal rolling mill were analyzed for uranium using a sequential extraction protocol involving a series of five increasingly aggressive solvents. The quantity of uranium extracted from the contaminated dirt by each reagent can aid in predicting the fate and transport of the uranium contamination in the environment. Uranium was separated from each fraction using anion exchange, electrodeposition and analyzed by alpha spectroscopy analysis. Results demonstrate that approximately 77 % of the uranium was extracted using NH4Ac in 25 % acetic acid. (author)

  8. Optimisation of beryllium-7 gamma analysis following BCR sequential extraction

    International Nuclear Information System (INIS)

    Graphical abstract: Showing decrease in analytical uncertainty using the optimal (combined preconcentrated sample extract) method. nv (no value) where extract activities were 7Be geochemical behaviour is required to support tracer studies. ► Sequential extraction with natural 7Be returns high analytical uncertainties. ► Preconcentrating extracts from a large sample mass improved analytical uncertainty. ► This optimised method can be readily employed in studies using low activity samples. - Abstract: The application of cosmogenic 7Be as a sediment tracer at the catchment-scale requires an understanding of its geochemical associations in soil to underpin the assumption of irreversible adsorption. Sequential extractions offer a readily accessible means of determining the associations of 7Be with operationally defined soil phases. However, the subdivision of the low activity concentrations of fallout 7Be in soils into geochemical fractions can introduce high gamma counting uncertainties. Extending analysis time significantly is not always an option for batches of samples, owing to the on-going decay of 7Be (t1/2 = 53.3 days). Here, three different methods of preparing and quantifying 7Be extracted using the optimised BCR three-step scheme have been evaluated and compared with a focus on reducing analytical uncertainties. The optimal method involved carrying out the BCR extraction in triplicate, sub-sampling each set of triplicates for stable Be analysis before combining each set and coprecipitating the 7Be with metal oxyhydroxides to produce a thin source for gamma analysis. This method was applied to BCR extractions of natural 7Be in four agricultural soils. The approach gave good counting statistics from a 24 h analysis period (∼10% (2σ) where extract activity >40% of total activity) and generated statistically useful sequential extraction profiles. Total recoveries of 7Be fell between 84 and 112%. The stable Be data demonstrated that the extraction

  9. Preparation of protein samples for gel electrophoresis by sequential extraction

    Institute of Scientific and Technical Information of China (English)

    钟伯雄; 翁宏飚; 等

    2002-01-01

    Since preparation and solubilization of protein samples are crucial factors in proteome research,the authors established a sequential extraction technique to prepare protein samples from the body wall of the 5th instar larvae of silkworm.Bombyx mori.Two kinds of protein samples were obtained from the body wall using the method.Between the two types of samples only about 15% proteins were identical;the majority were different,indicating that more species of proteins could be obtained with the sequential extraction method;which will be useful for preparation of protein samples for proteome study.

  10. Sequential biological process for molybdenum extraction from hydrodesulphurization spent catalyst.

    Science.gov (United States)

    Vyas, Shruti; Ting, Yen-Peng

    2016-10-01

    Spent catalyst bioleaching with Acidithiobacillus ferrooxidans has been widely studied and low Mo leaching has often been reported. This work describes an enhanced extraction of Mo via a two stage sequential process for the bioleaching of hydrodesulphurization spent catalyst containing Molybdenum, Nickel and, Aluminium. In the first stage, two-step bioleaching was performed using Acidithiobacillus ferrooxidans, and achieved 89.4% Ni, 20.9% Mo and 12.7% Al extraction in 15 days. To increase Mo extraction, the bioleached catalyst was subjected to a second stage bioleaching using Escherichia coli, during which 99% of the remaining Mo was extracted in 25 days. This sequential bioleaching strategy selectively extracted Ni in the first stage and Mo in the second stage, and is a more environmentally friendly alternative to sequential chemical leaching with alkaline reagents for improved Mo extraction. Kinetic modelling to establish the rate determining step in both stages of bioleaching showed that in the first stage, Mo extraction was chemical reaction controlled whereas in the subsequent stage, product layer diffusion model provided the best fit. PMID:27351900

  11. Sequential biological process for molybdenum extraction from hydrodesulphurization spent catalyst.

    Science.gov (United States)

    Vyas, Shruti; Ting, Yen-Peng

    2016-10-01

    Spent catalyst bioleaching with Acidithiobacillus ferrooxidans has been widely studied and low Mo leaching has often been reported. This work describes an enhanced extraction of Mo via a two stage sequential process for the bioleaching of hydrodesulphurization spent catalyst containing Molybdenum, Nickel and, Aluminium. In the first stage, two-step bioleaching was performed using Acidithiobacillus ferrooxidans, and achieved 89.4% Ni, 20.9% Mo and 12.7% Al extraction in 15 days. To increase Mo extraction, the bioleached catalyst was subjected to a second stage bioleaching using Escherichia coli, during which 99% of the remaining Mo was extracted in 25 days. This sequential bioleaching strategy selectively extracted Ni in the first stage and Mo in the second stage, and is a more environmentally friendly alternative to sequential chemical leaching with alkaline reagents for improved Mo extraction. Kinetic modelling to establish the rate determining step in both stages of bioleaching showed that in the first stage, Mo extraction was chemical reaction controlled whereas in the subsequent stage, product layer diffusion model provided the best fit.

  12. Phenolic Content and Antioxidant Activity of Hibiscus cannabinus L. Seed Extracts after Sequential Solvent Extraction

    OpenAIRE

    Shahid Iqbal; Maznah Ismail; Noordin Mohd Yusri; Kim Wei Chan

    2012-01-01

    A sequential solvent extraction scheme was employed for the extraction of antioxidant compounds from kenaf (Hibiscus cannabinus L.) seeds. Yield of extracts varied widely among the solvents and was the highest for hexane extract (16.6% based on dry weight basis), while water extract exhibited the highest total phenolic content (18.78 mg GAE/g extract), total flavonoid content (2.49 mg RE/g extract), and antioxidant activities (p < 0.05). DPPH and hydroxyl radical scavenging, β...

  13. Evalution of sequential extractions on dry and wet sediments

    OpenAIRE

    Baeyens, W.; Monteny, F.; Leermakers, M.; BOUILLON, S

    2003-01-01

    A five-step sequential extraction procedure was applied on dried and wet Ballastplaat Scheldt estuary sediments. When wet (fresh) sediments were used, all sample handling up to the 3rd extraction step, inclusive, was carried out under inert atmosphere. The repeatability of the procedure was very good on dry samples. For Fe as for Mn, RSD values are lower than 4%, except for Mn in the fifth extraction step where a spread of 10% is observed. The observed RSDs for Pb are of the same order of mag...

  14. Use of sequential extraction to assess metal partitioning in soils

    International Nuclear Information System (INIS)

    The state of heavy metal pollution and the mobility of Cd, Cu, Ni, Cr, Pb and Zn were studied in three texturally different agricultural soil profiles near a Cu-Ni smelter in Harjavalta, Finland. The pseudo-total concentrations were determined by an aqua regia procedure. Metals were also determined after division into four fractions by sequential extraction with (1) acetic acid (exchangeable and specifically adsorbed metals), (2) a reducing agent (bound to Fe/Mn hydroxides), (3) an oxidizing agent (bound to soil organic matter) and (4) aqua regia (bound to mineral structures). Fallout from the smelter has increased the concentrations of Cd, Cu and Ni in the topsoil, where 75-90% of Cd, 49-72% of Cu and 22-52% of Ni occurred in the first two fractions. Slight Pb and Zn pollution was evident as well. High proportions of mobile Cd, Cu and Ni also deeper in the sandy soil, closest to the smelter, indicated some downward movement of metals. The hydroxide-bound fraction of Pb dominated in almost all soils and horizons, while Ni, Cr and Zn mostly occurred in mineral structures. Aqua regia extraction is usefully supplemented with sequential extraction, particularly in less polluted soils and in soils that exhibit substantial textural differences within the profiles. - Sequential extraction is most useful with soils with low metal pollutant levels

  15. Utilizing a sequential injection system furnished with an extraction microcolumn as a novel approach for executing sequential extractions of metal species in solid samples

    DEFF Research Database (Denmark)

    Chomchoei, R.; Hansen, Elo Harald; Shiowatana, J.

    2007-01-01

    This communication presents a novel approach to perform sequential extraction of elements in solid samples by using a sequential injection (SI) system incorporating a specially designed extraction microcolumn. Based on the operation of the syringe pump, different modes of extraction are potentially...... feasible, uni-directional and bi-directional flow schemes being used herein. A three-step sequential extraction scheme, using conventionally adopted extractants, was used to evaluate the system by determining Ca, Fe, Mn, Cu, Zn in a soil certified reference material (NIST, SRM 2710). It is demonstrated...

  16. Sequential extraction of heavy metals during composting of urban waste

    Institute of Scientific and Technical Information of China (English)

    Ayari F.; Chairi R.; Kossai R.

    2008-01-01

    In urban waste (the first matter of compost), elements such as copper, nickel and lead may be found in metallic state (wire, pile, accumulator, etc.), which is considered as non-dependent state. The work undertaken at the laboratory of composting of the INRST in Henchir Lihoudia (Tunis) showed that the produced compost does not contain any mobile metallic element and the portion related to organic fraction (bioavailable) is tiny in size. We sup-posed that many reactions involving decomposition and complexation from elements related to the matrix compo-nents occurred during composting. The existence and importance of this phenomenon can be evaluated by studying the evolution of metal contents in the different fractions extracted sequentially during composting process.

  17. Correlation between the Results of Sequential Extraction and Effectiveness of Immobilization Treatment of Lead- and Cadmium-Contaminated Sediment

    OpenAIRE

    Milena B. Dalmacija; Miljana D. J. Prica; Dalmacija, Bozo D.; Roncevic, Srdjan D.; Rajic, Ljiljana M.

    2010-01-01

    The assessment of the quality of sediment from the Great Backi Canal (Serbia), based on the pseudo-total lead (Pb) and cadmium (Cd) content according to the corresponding Dutch standards and Canadian guidelines, showed its severe contamination with these two metals. A microwave-assisted BCR (Community Bureau of Reference of the Commission of the European Union) sequential extraction procedure was employed to assess their potential mobility and risk to the aquatic environment. Comparison of th...

  18. Sequential, successive, and simultaneous decoders for entanglement-assisted classical communication

    CERN Document Server

    Xu, Shen Chen

    2011-01-01

    Bennett et al. showed that allowing shared entanglement between a sender and receiver before communication begins dramatically simplifies the theory of quantum channels, and these results suggest that it would be worthwhile to study other scenarios for entanglement-assisted classical communication. In this vein, the present paper makes several contributions to the theory of entanglement-assisted classical communication. First, we rephrase the Giovannetti-Lloyd-Maccone sequential decoding argument as a more general "packing lemma" and show that it gives an alternate way of achieving the entanglement-assisted classical capacity. Next, we show that a similar sequential decoder can achieve the Hsieh-Devetak-Winter region for entanglement-assisted classical communication over a multiple access channel. Third, we prove several variations of a quantum simultaneous decoder for entanglement-assisted classical communication over a multiple access channel---some variations require that the code states and channel satisf...

  19. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin

    2010-01-01

    Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...... to the treatment and disposal of nuclear waste from decommissioning....

  20. Evaluation of degree of readsorption of radionuclides during sequential extraction in soil: comparison between batch and dynamic extraction systems

    DEFF Research Database (Denmark)

    Petersen, Roongrat; Hansen, Elo Harald; Hou, Xiaolin

    Sequential extraction techniques have been widely used to fractionate metals in solid samples (soils, sediments, solid wastes, etc.) due to their leachability. The results are useful for obtaining information about bioavailability, potential mobility and transport of element in natural environments...

  1. Sequential, successive, and simultaneous decoders for entanglement-assisted classical communication

    OpenAIRE

    Xu, Shen Chen; Wilde, Mark M.

    2011-01-01

    Bennett et al. showed that allowing shared entanglement between a sender and receiver before communication begins dramatically simplifies the theory of quantum channels, and these results suggest that it would be worthwhile to study other scenarios for entanglement-assisted classical communication. In this vein, the present paper makes several contributions to the theory of entanglement-assisted classical communication. First, we rephrase the Giovannetti-Lloyd-Maccone sequential decoding argu...

  2. Free radical-scavenging activity of sequential leaf extracts of Embothrium coccineum

    OpenAIRE

    Leyton Miguel; Mellado Marco; Jara Carlo; Montenegro Iván; González Sebastian; Madrid Alejandro

    2015-01-01

    The aim of this study was to evaluate the influence of phenolic, flavonoid, and anthraquinones from sequential extracts (n-hexane, dichloromethane, ethyl acetate, and ethanol) of Embothrium coccineum leaves on the antioxidant capacity, cell viability, and toxicity of the same, in order to find possible sources for novel antioxidants for food and pharmaceutical formulations. Antioxidant potential of sequential extracts was analyzed by five different assays: 2,2-diphenyl...

  3. Sequential extraction separation for determination of technetium-99 in radwastes by ICP-MS

    International Nuclear Information System (INIS)

    An approach based on sequential extraction separation and the subsequent ICP-MS measurement was introduced to determine 99Tc in radioactive wastes. The radwastes were firstly alkaline-fused and the 99Tc was separated by a sequential solvent extraction prior to ICP-MS measurement. NaDDC was selected as a chelation reagent in the solvent extraction processes. The influence of HCl and matrix concentration on the recovery yield and the effectiveness of removing isobar and unwanted radionuclides, such as 137Cs, 54Mn, 60Co and 110mAg, were evaluated. The designed sequential extraction procedure was optimized by an extraction experiment. The proposed technique is proven to be a simple and practical alternative for 99Tc determination in low-level radioactive wastes; chemical separation of 99Tc can be simplified and preconcentration such as precipitation and/or ion exchange, before the solvent extraction, can be excluded. (author)

  4. Sequential accelerated solvent extraction of polycyclic aromatic hydrocarbons with different solvents: performance and implication.

    Science.gov (United States)

    Ma, Xiaoxuan; Ran, Yong; Gong, Jian; Chen, Diyun

    2010-01-01

    Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) extracted by Soxhlet extraction (S-PAHs) with dichloromethane and routine accelerated solvent extraction (A-PAHs) with 1:1 toluene/methanol, respectively, were investigated in 24 soil samples from two cities in the center of the Pearl River Delta, South China. Polycyclic aromatic hydrocarbons, methylphenanthrene and perylene, in two soils, two sediments, and an immature oil shale were also sequentially extracted by accelerated solvent extraction (ASE) with each of four different organic solvents for three times. The A-PAHs' concentrations are 2.41 times the S-PAHs' concentrations. For sequential three ASEs, PAHs in the first extract account for 56 to 67% of their total concentrations in the sequential three extractions and toluene displays the best extraction performance among the four solvents. Diagnostic ratios of PAHs in Soxhlet extraction, routine ASE, and sequential ASE with each solvent for a given sample are very similar, suggesting their identical petrogenic and pyrogenic sources in the soils and sediments. But the PAH ratios for the shale have an obvious petrogenic origin. The perylene/5-ring PAH ratios indicate a diagenetic source, especially in the shale and sediments. The correlation analysis shows that A-PAHs/S-PAHs is better associated with the contents of total organic carbon (TOC) than those of black carbon (BC). The above results indicate the significant petrogenic origin of PAHs and the important effect of organic matter on their extraction and distribution in the investigated field soils/sediments. PMID:21284305

  5. A test of sequential extractions for determining metal speciation in sewage sludge-amended soils

    International Nuclear Information System (INIS)

    Sequential extraction procedures are widely used to estimate the quantity of trace metals bound to different solid fractions in contaminated soils. However, reliability of speciation of trace metals by these procedures remains largely unexamined. In the present study, the selectivity of each extraction step was tested by observing the effect of reversing the extraction order in the procedure. Two different sequential extraction methods and their reversed modes were used for metal fractionation in sewage sludge-amended soils. Significantly increased amounts of extractable metals (Cd, Cu, Pb and Zn) were evident in the sludge-amended soils compared to control soil by all extraction schemes; however, the amounts of metals extracted by each step were strongly dependent on the order of extraction, the type of reagents and the nature of the individual metals. Caution is advised in deducing the forms of soil metals from sequential extraction results from metal-contaminated soils. - Sequential extraction methods are of questionable accuracy for determining the chemical forms of certain trace metals in soils

  6. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts.

    Science.gov (United States)

    Noel, James D; Biswas, Pratim; Giammar, Daniel E

    2007-07-01

    Leaching of mercury from coal combustion byproducts is a concern because of the toxicity of mercury. Leachability of mercury can be assessed by using sequential extraction procedures. Sequential extraction procedures are commonly used to determine the speciation and mobility of trace metals in solid samples and are designed to differentiate among metals bound by different mechanisms and to different solid phases. This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acid-soluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto

  7. ASSESSMENT OF A SEQUENTIAL EXTRACTION PROCEDURE FOR PERTURBED LEAD CONTAMINATED SAMPLES WITH AND WITHOUT PHOSPHORUS AMENDMENTS

    Science.gov (United States)

    Sequential extraction procedures (SEP) attempt to determine the solid-phase association of elements in natural matrices. However, a major obstacle confronting SEP is species alteration of extracted metals before separation of solids from solution. The objectives of this study w...

  8. Comparison of three sequential extraction procedures to describe metal fractionation in anaerobic granular sludges

    NARCIS (Netherlands)

    Hullebusch, van E.D.; Sudarno, S.; Zandvoort, M.H.; Lens, P.N.L.

    2005-01-01

    In the last few decades. several sequential extraction procedures have been developed to quantify the chemical status of metals in the solid phase. In this study. three extraction techniques (modified [A. Tessier, P.G.C. Campbell, M. Bisson, Anal. Chem. 51 (1979) 844]: [R.C. Stover. L.E. Sommers, D.

  9. EVALUATION OF GEOCHEMICAL QUALITY CONTROL IN DETERMINATION OF Mn IN SOILS USING A SEQUENTIAL CHEMICAL EXTRACTION

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Sequential chemical extraction procedure has been widely used to partition particulate trace metals into various fractions and to describe the distribution and the statue of trace metals in geo-environment. One sequential chemical extraction procedure was employed here to partition various fractions of Mn in soils. The experiment was designed with quality controlling concept in order to show sampling and analytical error. Experimental results obtained on duplicate analysis of all soil samples demonstrated that the precision was less than 10% (at 95% confidence level). The accuracy was estimated by comparing the accepted total concentration of Mn in standard reference materials (SRMs) with the measured sum of the individual fractions. The recovery of Mn from SRM1 and SRM2 was 94.1% and 98.4% , respectively. The detection limit, accuracy and precision of the sequential chemical extraction procedure were discussed in detailed. All the results suggest that the trueness of the analytical method is satisfactory.

  10. Sequential extractions: A new way for protein quantification-data from peanut allergens.

    Science.gov (United States)

    Zhou, Ningling; Li, Wenying; Wu, Zhihua; Li, Xin; Yang, Anshu; Tong, Ping; Chen, Hongbing

    2015-09-01

    Quantification of certain protein contents in the matrix is essential in protein analyses. The amount of total protein in the matrix can be determined by the Kjeldahl method. However, few methods can quantify certain protein contents in the matrix without extracting all of them in solution. Extracting all of the contents is difficult for proteins, especially relatively insoluble ones. A five-step sequential extraction method was developed for the quantification of certain proteins in defatted peanut flour based on the relationship between the extracted protein contents and the extraction times. The extracted proteins (i.e., total protein, Ara h 1, and Ara h 2) were quantitatively analyzed in each extraction of the same condition. An exponential equation was obtained between the extraction times and the respective amount of extracted protein as well as both the total protein and a particular protein. In particular, the amount of protein extracted each time can be a geometric sequence. If all proteins can be extracted with sufficient extraction times, the protein contents in the peanut matrix can be calculated using a mathematical summation formula. This sum should be all proteins in the matrix. The five-step sequential extraction method can provide a means to quantify certain proteins in the matrix.

  11. Sequential extraction evaluation of soil washing for radioactive contamination

    International Nuclear Information System (INIS)

    This paper reports on surveys of soil washing as currently applied, particularly in Europe, which show a key similarity in relying on size classification for the primary contaminant separation. Wet screening is used to remove particulate below a 63 to 74 micron cutoff range, which is then disposed of as hazardous waste. Though chemical extraction may be employed in conjunction with screening, it is commonly accepted that fine particulate present in solution may resorb extracted contaminants, and it is not cost effective to continue to wash the fines. Testing of more aggressive flowsheets is commonly limited to trail-and-error extraction with mineral acids which may dissolve a significant fraction (4-5 wt%) of the environmentally benign soil matrix. The Environmental Protection Agency's guidance on soil washing treatability studies suggests a 50% reduction of contamination in particles over 2mm as a reasonable cutoff for choosing soil washing for further development

  12. Sequential, successive, and simultaneous decoders for entanglement-assisted classical communication

    Science.gov (United States)

    Xu, Shen Chen; Wilde, Mark M.

    2013-01-01

    Bennett et al. showed that allowing shared entanglement between a sender and receiver before communication begins dramatically simplifies the theory of quantum channels, and these results suggest that it would be worthwhile to study other scenarios for entanglement-assisted classical communication. In this vein, the present paper makes several contributions to the theory of entanglement-assisted classical communication. First, we rephrase the Giovannetti-Lloyd-Maccone sequential decoding argument as a more general "packing lemma" and show that it gives an alternate way of achieving the entanglement-assisted classical capacity. Next, we show that a similar sequential decoder can achieve the Hsieh-Devetak-Winter region for entanglement-assisted classical communication over a multiple access channel. Third, we prove the existence of a quantum simultaneous decoder for entanglement-assisted classical communication over a multiple access channel with two senders. This result implies a solution of the quantum simultaneous decoding conjecture for unassisted classical communication over quantum multiple access channels with two senders, but the three-sender case still remains open (Sen recently and independently solved this unassisted two-sender case with a different technique). We then leverage this result to recover the known regions for unassisted and assisted quantum communication over a quantum multiple access channel, though our proof exploits a coherent quantum simultaneous decoder. Finally, we determine an achievable rate region for communication over an entanglement-assisted bosonic multiple access channel and compare it with the Yen-Shapiro outer bound for unassisted communication over the same channel.

  13. Independent versus sequential reading in ROC studies of computer-assist modalities

    Science.gov (United States)

    Beiden, Sergey V.; Wagner, Robert F.; Doi, Kunio; Nishikawa, Robert M.; Freedman, Matthew T.; Lo, Shih-Chung B.; Xu, Xin-Wei

    2002-04-01

    This paper provides results of a statistical analysis of two methods for arranging the temporal sequencing of the unaided vs computer-assisted reading in multiple-reader, multiple- case (MRMC) receiver operating characteristic (ROC) studies of computer-aided detection of solitary pulmonary nodules (SPNs) on chest radiographs. The modes are the Independent mode, in which the readings are separated by a time on the order of one month, and the Sequential mode, in which the CAD-assisted reading immediately follows the unassisted reading. The method of Beiden, Wagner, Campbell (BWC) was used to decompose the variance of the ROC area summary accuracy measure into the components that are correlated across unaided and aided reading conditions and the components that are uncorrelated across these reading conditions. The latter are the only components of variability that contribute to the uncertainty in a measurement of the difference in reader performance between reading conditions. These uncorrelated components were dramatically reduced in the Sequential reading mode compared to the Independent reading mode-while the total reader variability remained almost constant. The results were remarkably similar across two independent studies analyzed. This may have important practical consequences because the Sequential mode is the least demanding on reader logistics and time.

  14. Sampling informative/complex a priori probability distributions using Gibbs sampling assisted by sequential simulation

    DEFF Research Database (Denmark)

    Hansen, Thomas Mejer; Mosegaard, Klaus; Cordua, Knud Skou

    2010-01-01

    Markov chain Monte Carlo methods such as the Gibbs sampler and the Metropolis algorithm can be used to sample the solutions to non-linear inverse problems. In principle these methods allow incorporation of arbitrarily complex a priori information, but current methods allow only relatively simple...... priors to be used. We demonstrate how sequential simulation can be seen as an application of the Gibbs sampler, and how such a Gibbs sampler assisted by sequential simulation can be used to perform a random walk generating realizations of a relatively complex random function. We propose to combine...... this algorithm with the Metropolis algorithm to obtain an efficient method for sampling posterior probability densities for nonlinear inverse problems....

  15. Combination of heterogeneous EEG feature extraction methods and stacked sequential learning for sleep stage classification.

    Science.gov (United States)

    Herrera, L J; Fernandes, C M; Mora, A M; Migotina, D; Largo, R; Guillen, A; Rosa, A C

    2013-06-01

    This work proposes a methodology for sleep stage classification based on two main approaches: the combination of features extracted from electroencephalogram (EEG) signal by different extraction methods, and the use of stacked sequential learning to incorporate predicted information from nearby sleep stages in the final classifier. The feature extraction methods used in this work include three representative ways of extracting information from EEG signals: Hjorth features, wavelet transformation and symbolic representation. Feature selection was then used to evaluate the relevance of individual features from this set of methods. Stacked sequential learning uses a second-layer classifier to improve the classification by using previous and posterior first-layer predicted stages as additional features providing information to the model. Results show that both approaches enhance the sleep stage classification accuracy rate, thus leading to a closer approximation to the experts' opinion. PMID:23627659

  16. Physicochemical Properties of Pectin from Retama raetam Obtained using Sequential Extraction

    Science.gov (United States)

    Kacem, I.; Majdoub, H.; Roudesli, S.

    Water-soluble polysaccharides were extracted sequentially from Retama raetam. Dried Alcohol-Insoluble Residues (AIR) of Retama raetam were treated sequentially with deionised water, ammonium oxalate and basic solutions and purified by ultrafiltration. The resulting pectin extracts analysed for some physicochemical parameters. The results show that pectin yield (62% dry AIR), uronic acid (260-640 mg g-1), neutral sugars (320-540 mg g-1), degree of methylation (20-31%) and acetylation (2-19%), molar mass (8. 93x104-3.42x105 g mol-1) and intrinsic viscosity (27- 47 mL g-1) varied with the various extraction methods used. Extraction with ammonium oxalate solution gave the highest pectin yield, with high molar mass and degree of methylation.

  17. Single column sequential extraction of Ra, Nd, Th, Pa and U from a natural sample

    OpenAIRE

    Jeandel, C.; Venchiarutti, C.; Bourquin, M.; Pradoux, C; Lacan, F.; P. van Beek; Riotte, Jean

    2011-01-01

    A new procedure allowing the sequential extraction of Ra, Nd, Th, Pa and U from the same initial natural sample (sea or river waters, particles, sediments, rocks) is proposed. Extraction recoveries were better than 90%. Procedural blanks ranged from 80 pg (for Nd) to below 1 fg, the detection limit of the MC-ICP-MS used (for Pa); all were negligible compared with the amounts of elements currently determined. Based on classical anionic resins attached to a peristaltic pump allowing precise flo...

  18. Comparison between sequential and single extraction procedures for metal speciation in fresh and dried Sedum Plumbizincicola

    Institute of Scientific and Technical Information of China (English)

    宋祖威; 仲兆平; 钟道旭; 吴龙华; 骆永明

    2015-01-01

    Sequential and single extraction procedures were applied to both fresh and driedSedum Plumbizincicola leaves and stems. The extractants, different from those of soil, sediment or sewage sludge metal fractions, were water, 80% (v/v) ethanol, 1 mol/L NaCl, 2% HAc and 0.6 mol/L HCl. Zn, Cd and Cu in the extracts and samples were measured by flame atomic adsorption spectrometry. In sequential extraction procedures, water soluble form and ethanol soluble form are the main fractions for Zn, while water soluble form and NaCl soluble form for Cd, and comparatively uniform distribution for Cu with the residue form most and HCl soluble form second. Single extraction procedures are used to compare the extraction efficiencies of the five reagents to screen appropriate extractants and operating conditions for liquid extraction to deal with large amount of harvested metal-contained biomass, which will pose a threat to the environment if treated improperly. The sequences of extraction efficiencies are HCl>NaCl≈HAc>Water≈Ethanol for Zn and HCl≈NaCl≈HAc>Water>Ethanol for Cd. As for Cu, all the five extractants cannot effectively extract Cu, but HCl achieves a higher efficiency (>70% in fresh samples, and 45%−60% in dried samples). Besides, extraction efficiencies for most extractants in fresh samples are higher than those in dried samples, and extraction efficiencies of stems and leaves for the five extractants are close. The two extraction procedures can obtain high degree of accuracy with the relative standard deviation (RSD) lower than 10%, and metal recoveries are controlled between 80%−120% with most of 90%−110%.

  19. Sequential Extraction of Aluminum and Iron from Acidic Soils by Chemical Selective Dissolution Methods

    Institute of Scientific and Technical Information of China (English)

    HEJIZHENG; A.VIOLANTE; 等

    1998-01-01

    Potassium chloride, Na-pyrophosphate,CuCl2,NH4-oxalate,dithionit-citrate-bicarbonate(DCB) and Na-citrate solutions were employed to etract aluminum(Al) and iron(Fe) sequentially and separately from 15 acidic soils located at the Mangshan Mountains,Hunan Province,China,Many evidences showed that separate pyrophosphate extracted mainly KCl-extractable Al,organo-Al complexes and some inorganic Al compounds,whereas separate CuCl2 extracted KCl-extractable Al and some organo-Al complexes,CuCl2 extracted much less amounts of Al than pyrophosphate did from the soils .Separate oxalate did not extract all KCl-pyrophosphate-CuCl2-oxalate seuentially extractable Al and Fe ,Also,separate DCB did not extract all KCl-pyrophosphate-CuCl2-oxalate-DCB sequentially extractable Al. The forms of Al extacted by oxalate and DCB from the soils were majorly noncrystalline.The interlayered materials of 1.4-nm intergrade minerals of the soils were attributed mainly to hydroxy Al polymers.

  20. Antibacterial activity of sequentially extracted organic solvent extracts of fruits, flowers and leaves of Lawsonia inermis L. from Jaffna

    Institute of Scientific and Technical Information of China (English)

    E Christy Jeyaseelan; S Jenothiny; MK Pathmanathan; JP Jeyadevan

    2012-01-01

    To reveal the antibacterial activity of sequentially extracted different cold organic solvent extracts of fruits, flowers and leaves of Lawsonia inermis (L. against) some pathogenic bacteria. Methods: Powders of fruits, flowers and leaves of L. inermis were continuously extracted with dichloromethane (DCM), ethyl acetate and ethanol at ambient temperature. The dried extracts were prepared into different concentrations and tested for antibacterial activity by agar well diffusion method, and also the extracts were tested to determine the available phytochemicals.Results:Except DCM extract of flower all other test extracts revealed inhibitory effect on all tested bacteria and their inhibitory effect differed significantly (P<0.05). The highest inhibitory effect was showed by ethyl acetate extract of flower against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), and ethyl acetate extract of fruit on Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis). The ethyl acetate and ethanol extracts of flower, fruit and leaf expressed inhibition even at 1 mg/ 100 μl against all test bacteria. Among the tested phytochemicals flavonoids were detected in all test extracts except DCM extract of flower.Conclusions:The study demonstrated that the ethyl acetate and ethanol extracts of fruit and flower of L. inermis are potentially better source of antibacterial agents compared to leaf extracts of respective solvents.

  1. Preliminary phytochemical investigation and thin layer chromatography profiling of sequential extracts of Moringa oleifera pods

    Directory of Open Access Journals (Sweden)

    Veena Sharma

    2013-01-01

    Full Text Available Context: Moringa oleifera Lam (Moringaceae is a highly valued plant, distributed in many countries of the tropics and subtropics. It has an impressive range of medicinal uses with high nutritional value. Aim: The present study, primarily aims to carry out a preliminary phytochemical screening so as to detect the major class of compounds present in M. oleifera and to perform thin layer chromatography (TLC profiling of all sequential extracts. Materials and Methods: Phytochemical analysis was performed by various qualitative methods and TLC profiling was carried out using various solvent system of varying polarity. Results and Conclusions: Qualitative phytochemical analysis reflects the presence of phenolics, triterpenoids, cardiac glycosides, steroid, alkaloids and saponin in the plant extract. TLC profiling of the M. oleifera pods was carried out using sequential extracts of petroleum ether, benzene, petroleum ether, benzene, chloroform, ethyl acetate, ethanol and water respectively. The results obtained in the present investigation indicated M. oleifera pods as a rich source of natural antioxidants.

  2. Application and research advancement on the microwave-assisted extraction

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; ZHENG Xianzhe

    2007-01-01

    This paper summarized application and research advancement of the microwave-assisted extraction in the agriculture,food industry, environmental analytical chemistry, traditional Chinese medicine industry, and so on. The microwave-assisted extraction was manifested to be a simple device, wide area of application, high extraction efficiency, good reproducibility and low consumption of agent and time as well as low environmental pollution. At present, industrialization question of the microwave-assisted extraction technology has been attached importance, which will impel the microwave-assisted extraction technology to more development in the future.

  3. Sequential solvent extraction for forms of antimony in five selected coals

    Science.gov (United States)

    Qi, C.; Liu, Gaisheng; Kong, Y.; Chou, C.-L.; Wang, R.

    2008-01-01

    Abundance of antimony in bulk samples has been determined in five selected coals, three coals from Huaibei Coalfield, Anhui, China, and two from the Illinois Basin in the United States. The Sb abundance in these samples is in the range of 0.11-0.43 ??g/g. The forms of Sb in coals were studied by sequential solvent extraction. The six forms of Sb are water soluble, ion changeable, organic matter bound, carbonate bound, silicate bound, and sulfide bound. Results of sequential extraction show that silicate-bound Sb is the most abundant form in these coals. Silicate- plus sulfide-bound Sb accounts for more than half of the total Sb in all coals. Bituminous coals are higher in organic matterbound Sb than anthracite and natural coke, indicating that the Sb in the organic matter may be incorporated into silicate and sulfide minerals during metamorphism. ?? 2008 by The University of Chicago. All rights reserved.

  4. Determination of sequential extracted uranium speciation in geological samples with HR-ICP-MS method

    International Nuclear Information System (INIS)

    This paper presents a method of determing uranium speciation in geological samples by means of sequential extraction procedure with HR-ICP-MS and its application to sandstone uranium exploration. The extraction chemical procedure is modified from Tessier, uranium in sample is classified into five speclarion: exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to sulfide-organic matter, and residual. The uranium is extracted respectively and the extractants are measured by the high-resolution inductively coupled mass spectrometry (HR-ICP-MS) with high sensitivity and low background. The extraction procedure has been proved to be satisfactory by means of national reference standard materials, international reference standard materials, and artificial uranium mine sample. Experiment results obtained on replicate samples demonstrate that the relative standard deviation (RSD) of the sequential extraction procedure followed by HR-ICP-MS is 2.6 % for bound to carbonates, 4.0% for bound to sulfide -organic matter, 6.0% for residual, 6.1% bound to Fe-Mn oxides, and 26% for exchangeable fraction. The ratio of uranium in bound to uranium carbonates in residual can be used to indicated the probability of buried uranium deposit. (authors)

  5. Distributions and concentrations of thallium in Korean soils determined by single and sequential extraction procedures.

    Science.gov (United States)

    Lee, Jin-Ho; Kim, Dong-Jin; Ahn, Byung-Koo

    2015-06-01

    The objectives of this study were to investigate the distribution of thallium in soils collected near suspected areas such as cement plants, active and closed mines, and smelters and to examine the extraction of thallium in the soils using 19 single chemical and sequential chemical extraction procedures. Thallium concentrations in soils near cement plants were distributed between 1.20 and 12.91 mg kg(-1). However, soils near mines and smelters contained relatively low thallium concentrations ranging from 0.18 to 1.09 mg kg(-1). Thallium extractability with 19 single chemical extractants from selected soils near cement plants ranged from 0.10% to 8.20% of the total thallium concentration. In particular, 1.0 M NH4Cl, 1.0 M (NH4)2SO4, and 1.0 M CH3COONH4 extracted more thallium than other extractants. Sequential fractionation results of thallium from different soils such as industrially and artificially contaminated soils varied with the soil properties, especially soil pH and the duration of thallium contamination. PMID:25836266

  6. Sequential extraction partitioning of trace and nutrient elements in ashes from biomass firing district heating plants

    Directory of Open Access Journals (Sweden)

    Šyc M.

    2013-04-01

    Full Text Available Four different ashes from three district heating plants firing biomass were studied with the respect to their potential application as soil fertilizers. Major and trace elements content and some important characteristics of the studied ashes are also presented. Five stage sequential extraction procedure was used for the determination of distribution and speciation of As, Ca, Cd, Cr, Cu, K, Mg, Na, Ni, Pb and Zn in studied ash samples.

  7. Heavy metals partioning in three French forest soils by sequential extraction procedure

    OpenAIRE

    Probst, Anne; Hernandez, Laura; Probst, Jean-Luc

    2003-01-01

    To know the concentration of heavy metal associated to chemical compounds is important to evaluate the environmental risks on soils, particularly regarding ion bioavailability. The relative mobility and strength of binding of heavy metals to the soil components can be studied using a sequential extraction procedure which provides a meaningful comparison between different soil profiles. The heavy metals partitioning bas been identified in three different french forest soils : one cambic podzol...

  8. Sequential Extraction Partitioning of Trace and Nutrient Elements in Ashes from Biomass Firing District Heating Plants

    OpenAIRE

    Šyc M.; Tošnarová M.; Hrma J.; Pohořelý M.; Svoboda K.; Punčochář M.

    2012-01-01

    Four different ashes from three district heating plants firing biomass were studied with the respect to their potential application as soil fertilizers. Major and trace elements content and some important characteristics of the studied ashes are also presented. Five stage sequential extraction procedure was used for the determination of distribution and speciation of As, Ca, Cd, Cr, Cu, K, Mg, Na, Ni, Pb and Zn in studied ash samples.

  9. Extracting regulatory modules from gene expression data by sequential pattern mining

    OpenAIRE

    Kim Mingoo; Shin Hyunjung; Su Chung Tae; Joung Je-Gun; Kim Ju Han

    2011-01-01

    Abstract Background Identifying a regulatory module (RM), a bi-set of co-regulated genes and co-regulating conditions (or samples), has been an important challenge in functional genomics and bioinformatics. Given a microarray gene-expression matrix, biclustering has been the most common method for extracting RMs. Among biclustering methods, order-preserving biclustering by a sequential pattern mining technique has native advantage over the conventional biclustering approaches since it preserv...

  10. EVALUATION OF GEOCHEMICAL QUALITY CONTROL IN DETERMINATION OF Mn IN SOILS USING A SEQUENTIAL CHEMICAL EXTRACTION

    Institute of Scientific and Technical Information of China (English)

    DONGDe-ming; FANGChun-sheng; 等

    2002-01-01

    Sequential chemical extraction procedure has been widely used to partition particulate trace metals into vari-ous fractions and to describe the distribution and the statue of trace metals in geo-environment.One sequential chemical extraction procedure was employed here to partition various fractions of Mn in soils.The experiment was designed with quality controlling concept in order to show sampling and analytical error.Experimental results obtained on duplicate analy-sis of all soil samples demonstrated that the precision was less than 10%(at 95% confidence level).The accuracy was estimated by comparing the accepted total concentration of Mn in standard reference materials (SRMs) with the measured sum of the individual fractions.The recovery of Mn from SRM1 and SRM2 was 94.1% and 98.4%,respectively.The detection limit,accuracy and precision of the sequential chemical extraction procedure were discussed in detailed.All the results suggest that the trueness of the analytical method is satisfactory.

  11. Arsenic fractionation by sequential extractions in standard reference materials and industrially contaminated soil samples: Applicability and drawbacks

    Energy Technology Data Exchange (ETDEWEB)

    Herreweghe, S. van; Swennen, R. [Fysico-Chemische Geologie, Heverlee (Belgium)

    2003-07-01

    Availability mobility (phyto)toxycity and potential risk of contaminants is strongly affected by the manner of appearance of elements, the so-called speciation. Operational fractionation methods like sequential extractions have been applied for a long time to determine the solid phase speciation of heavy metals since direct determination of specific chemical compounds can not always be easily achieved. The aim of this research was to assess the applicability of sequential extractions on highly contaminated soils where arsenic is also present as discrete As-bearing minerals. Sequential extractions are mostly developed to fractionate heavy metals occurring in trace amounts and their applicability on highly contaminated samples remains insufficiently studied. There was, furthermore, a need to evaluate sequential extraction schemes specifically focussing on metalloid element extraction such as arsenic. (orig.)

  12. Application of a Three-Stage Sequential Extraction Procedure for the Determination of Extractable Metal Contents in Highway Soils

    OpenAIRE

    TOKALIOĞLU, Şerife; BİROL, Şenol KARTAL and Gökhan

    2003-01-01

    A sequential extraction procedure, a three-step protocol proposed by the Standards, Measurements and Testing programme (SM & T--formerly BCR) of the European Union, was applied to soil samples for the determination of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn). This procedure provides measurements of extractable metals from media such as acetic acid (0.11 mol L-1), hydroxylammonium chloride (0.1 mol L-1) and hydrogen peroxide (8.8 mol L-1) plus ammonium acetate (1 mol L - 1), ...

  13. Sequential extraction for radionuclide fractionation in soil samples: a comparative study

    International Nuclear Information System (INIS)

    Two sequential extraction procedures, Tessier's method (Anal. Chem. 51(7) (1979) 844), and a current version known as Schultz's method (J. Environ. Radioact. 40(2) (1998) 155), were compared. The two procedures were applied to a natural soil sample that presents high activity concentrations in natural radionuclides of the 238U series. Reproducibility studies of each method and a comparison between the two sets of results were performed for uranium, thorium, and radium. The results were different for each radionuclide. Analysis of the extracted fractions was carried out by alpha spectrometry

  14. Microwave-assisted extraction of polysaccharides from solanum nigrum

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-qing; LIU-qin; JIANG xin-yu; ZENG fan

    2005-01-01

    The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the structures of polysaccharides were investigated. The extract was analyzed by the modified phenol-sulfuric acid method at 490 nm. The optimum experimental parameters were obtained by orthogonal experiments as follows: extraction time 15 min, microwave radiation power 455 W and the process ratio of materials mass to solvent volume 1∶20. The results show that compared with the conventional reflux extraction, the microwave-assisted extraction has a higher yield in shorter time, with no effect on the finally obtained polysaccharides as seen from the FT-IR spectra. The scanning electron microscopy images reveal that the mechanism of the extraction is related to the structural changes of the plant cells in different extracting conditions.

  15. Fractionation of U, Th, Ra and Pb from boreal forest soils by sequential extractions

    International Nuclear Information System (INIS)

    Highlights: • A five-step sequential extraction was performed to boreal forest soil samples. • Extractions gave information about mobility and sorption of natural radionuclides. • Fractionation of U, Th, Pb and Ra varied between the sample depth and grain size. • U, Pb and Fe fractionation suggested more reducing conditions in the subsoil samples. • Ra was the only radionuclide that could be regarded as mobile. - Abstract: To determine the mobility of natural radionuclides in boreal forest soil, a five-step sequential extraction procedure was carried out on soil samples taken from various depths down to 3 m on Olkiluoto Island, Finland, where there are plans to construct a spent nuclear fuel disposal repository in the bedrock. The extracted fractions studied were exchangeable, acid-soluble, reducible, oxidizable and tightly bound. It was found that the extractability of most of the radionuclides studied was dependent on the sample grain size and depth. All the elements were concentrated in the smallest grain size samples (<0.063 mm). The extraction behaviour of Th, however, did not vary with sample depth, and only about 10% of the Th was extracted by the time of the final extraction step. Stable Pb and 210Pb, as well as Ba and Ra concentrations were strongly correlated in the extractions. Radium and Ba were leached more readily than the other elements; approximately 17% of the total Ra was found in the first fraction extracted, representing exchangeable ions. Uranium was more mobile in the topsoil horizons than in the lower horizons. In the topsoil samples, an average of 51% of the extractable U was leached in the second extraction step, representing the elements soluble in weak acids, whereas only 13% of the U in the subsoil samples was extracted in this step. This is probably due to changes in soil redox conditions lower down the soil profile. The extraction behaviour of Pb and Fe also suggests the presence of more reducing conditions in the deeper soil

  16. Study of metal fractionation in river sediments. A comparison between kinetic and sequential extraction procedures

    International Nuclear Information System (INIS)

    The extraction kinetic of trace metals (Cd, Cu, Pb, and Zn) in river sediments by four extraction agents was studied. As extractants ammonium acetate, acetic acid, hydroxylamine and EDTA solutions were assayed. These reagents can leach the metals more or less selectively from several metal compartments of sediments. The metal leaching kinetic model permits classification of the metal species in labile and moderately-labile ones. The combination of two or more non specific reagents permits a high characterisation of metal distribution and leachability. The results obtained with this model in four river sediments were compared with data obtained by the SM and T sequential extraction procedure, in order to characterise the chemical nature of leached metal. - A leached metal kinetic study may be a good way to study the mobility of trace metals in sediments

  17. Sequential extraction for the speciation of some heavy metals in soils

    International Nuclear Information System (INIS)

    The five step sequential extraction for speciation of copper and nickel originally designed for sediments has been applied to soil samples. The extractant solutions were: 1 mol/l ammonium acetate, 1 mol/l hydroxylammonium chloride in 25% acetic acid (1:1), 0.1 mol/l hydrochlorid acid, 0.5 mol/l sodium hydroxide and 8 mol/l nitric acid. The residue was decomposed by HF and HNO3. Using this procedure the metal fraction bound to the organic matter can be distinguished. The concentrations of analytes were determined in the soil extracts by FAAS and ETAAS. Accuracy was assessed by comparing the sum of the contents of copper and nickel in soil extracts with the total certified values of CRMs of soils. The overall recovery values for nickel was 84-105% and for copper 105-114%. (author)

  18. Sequential Extraction of Natural Surface Coatings: Comparison with Single Stage Extraction and Its Application in Investigating Adsorption Characteristics of Surface Coating Components for Metals

    Institute of Scientific and Technical Information of China (English)

    HUA Xiu-yi; LIU Xiao-xue; DONG De-ming; LI Ming; LI Yao-rui

    2012-01-01

    Multistage sequential extraction with different sequences was applied to extracting natural surface coatings(NSCs),and the results were compared with those by single stage extraction technique.The optimal sequential extraction scheme with the best performance was selected and incorporated into the method of selective extraction followed by adsorption and statistic analyses to study the adsorption parameters of Fe oxides,Mn oxides and organic matters in NSCs for Pb and Cd,to validate the applicability of the sequential extraction scheme.The Langmuir adsorption parameters of each component of surface coating estimated according to the adsorption data of single stage extraction of NSCs were all similar to those of sequential extraction of NSCs,and the maximum difference between the metal adsorption abilities of the components estimated via the two extraction techniques was only about 20%,indicating that either extraction techniques could be used.The optimal sequential extraction scheme obtained was first extracted with NH2OH·HCl,then with Na2S2O4,and finally with oxalic acid.

  19. Study on microwave-assisted extraction of coal

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong; LU Jun-qing; GE Ling-mei; Li Jian-wei

    2007-01-01

    The effect of different factors on coal extraction yield-temperature,solvent,coal type and irradiation time were investigated for different China coals under microwave-assisted extraction(MAE).The results show that the optimum temperature for ethanol,acetone and THF are 393,373 and 373 K respectively and the extraction yield of THF is higher than that of other two solvents under MAE.Extraction with several single organic solvents were conducted for the 5 typical China coals-Shenfu,Tongchuan,Panzhihua,Yitai and Huating coal under microwave-assisted extraction and Soxhlet extraction.Resuits indicat that extraction yield of ethylenediamine,ethanol,acetone,tetrahydrofuran under MAE are are higher than that of Soxhlet extraction and MAE required less time.Tonqchuan coal extracts of ethanol and acetone which were extracted by MAE and Soxhlet extraction were analyzed by GC/MS.

  20. Correlation between the Results of Sequential Extraction and Effectiveness of Immobilization Treatment of Lead- and Cadmium-Contaminated Sediment

    Directory of Open Access Journals (Sweden)

    Milena B. Dalmacija

    2010-01-01

    Full Text Available The assessment of the quality of sediment from the Great Backi Canal (Serbia, based on the pseudo-total lead (Pb and cadmium (Cd content according to the corresponding Dutch standards and Canadian guidelines, showed its severe contamination with these two metals. A microwave-assisted BCR (Community Bureau of Reference of the Commission of the European Union sequential extraction procedure was employed to assess their potential mobility and risk to the aquatic environment. Comparison of the results of sequential extraction and different criteria for sediment quality assessment has led to somewhat contradictory conclusions. Namely, while the results of sequential extraction showed that Cd comes under the high-risk category, Pb shows low risk to the environment, despite its high pseudo-total content. The contaminated sediment, irrespective of the different speciation of Pb and Cd, was subjected to the same immobilization, stabilization/solidification (S/S treatments using kaolinite, montmorillonite, kaolinite-quicklime, montmorillonite-quicklime, fly ash, zeolite, or zeolite-fly ash combination. Semi-dynamic leaching tests were conducted for Pb- and Cd-contaminated sediment in order to assess the long-term leaching behavior of these metals. In order to simulate “worst case” leaching conditions, the semi-dynamic leaching test was modified using 0.014 M acetic acid (pH = 3.25 and humic acid solutions (20 mg TOC l-1 as leachants instead of deionized water. The effectiveness of S/S treatment was evaluated by determining diffusion coefficients (De and leachability indices (LX. The standard toxicity characteristic leaching procedure (TCLP was applied to evaluate the extraction potential of Pb and Cd. A diffusion-based model was used to elucidate the controlling leaching mechanisms. Generally, the test results indicated that all applied S/S treatments were effective in immobilizing Pb and Cd, and the treated sediments may be considered acceptable

  1. Use Of Sequential Extraction Procedures For The Natural Attenuation Of Radionuclides

    International Nuclear Information System (INIS)

    Metals at impacted and unimpacted sites are generally found in one of the following fractions: (1) dissolved, (2) occupying exchange sites of inorganic and organic soil constituents, (3) specifically adsorbed on inorganic soil constituents, (4) complexed with insoluble soil organics, (5) precipitated or coprecipitated as solids, or (6) occluded within the structure of primary and/or secondary minerals. Sequential extraction of soils and sediments has been developed to selectively remove and quantify contaminants from various defined geochemical fractions or mineral phases. The objective of these sequential extraction procedures (SEPs) is not to identify the actual form of a given metal in a soil or similar material, but to categorize the metals into defined geochemical fractions: e.g., exchangeable, acid extractable, reducible, organic, oxidizable, or residual. SEPs provide: (1) information on likely metal immobilization mechanism(s), (2) a mass balance of metal immobilization mechanisms, which can be used to gauge long term stability and develop site management criteria, (3) estimates on the fraction of metal in soil or sediment that may have ready impact to human health and the environment (free ion concentration from the exchangeable extraction), (4) estimates on the fraction of metal in soil or sediment that has the potential to be bioaccumulated in less-complex organisms and plants, (5) estimates on the fraction of metal in soil or sediment that has the potential to be bioaccumulated by more complex organisms

  2. Beryllium solubility in occupational airborne particles: Sequential extraction procedure and workplace application.

    Science.gov (United States)

    Rousset, Davy; Durand, Thibaut

    2016-01-01

    Modification of an existing sequential extraction procedure for inorganic beryllium species in the particulate matter of emissions and in working areas is described. The speciation protocol was adapted to carry out beryllium extraction in closed-face cassette sampler to take wall deposits into account. This four-step sequential extraction procedure aims to separate beryllium salts, metal, and oxides from airborne particles for individual quantification. Characterization of the beryllium species according to their solubility in air samples may provide information relative to toxicity, which is potentially related to the different beryllium chemical forms. Beryllium salts (BeF(2), BeSO(4)), metallic beryllium (Bemet), and beryllium oxide (BeO) were first individually tested, and then tested in mixtures. Cassettes were spiked with these species and recovery rates were calculated. Quantitative analyses with matched matrix were performed using inductively coupled plasma mass spectrometry (ICP-MS). Method Detection Limits (MDLs) were calculated for the four matrices used in the different extraction steps. In all cases, the MDL was below 4.2 ng/sample. This method is appropriate for assessing occupational exposure to beryllium as the lowest recommended threshold limit values are 0.01 µg.m(-3) in France([) (1) (]) and 0.05 µg.m(-3) in the USA.([ 2 ]) The protocol was then tested on samples from French factories where occupational beryllium exposure was suspected. Beryllium solubility was variable between factories and among the same workplace between different tasks. PMID:26327570

  3. Sequential extraction of fallout radiocesium from the soil. Small scale and large scale spatial variability

    International Nuclear Information System (INIS)

    The reproducibility, the small scale as well as the large scale variability of 137Cs extracted sequentially from the soil by using a modified Tessier procedure was investigated at several grassland sites in Bavaria/Germany and in the Chernobyl area. Because undisturbed grassland soils are never homogeneous with respect to their soil properties, all sequential extractions at the German sites were carried out at each plot separately for different soil layers (e.g., 0-2, 2-5, 5-10, 10-15, 15-20 and 20-30 cm). The results show that the coefficients of variation (CV) for the reproducibility of the extraction procedure for 137Cs was (with some exceptions) around 10-20% for all fractions. For the small scale variability of 137Cs (samples within an area of 10 x 10 m2) the values for the CV were (again with a few exceptions) in the same range. Compared to that, the large scale variability of extractable 137Cs (random soil samples within an area of 100 x 200 km2) was higher for all fractions, even though only moderately. The implications of these results with respect to a sampling design are discussed. (author)

  4. Pumpkin (Cucurbita maxima) seed proteins: sequential extraction processing and fraction characterization.

    Science.gov (United States)

    Rezig, Leila; Chibani, Farhat; Chouaibi, Moncef; Dalgalarrondo, Michèle; Hessini, Kamel; Guéguen, Jacques; Hamdi, Salem

    2013-08-14

    Seed proteins extracted from Tunisian pumpkin seeds ( Cucurbita maxima ) were investigated for their solubility properties and sequentially extracted according to the Osborne procedure. The solubility of pumpkin proteins from seed flour was greatly influenced by pH changes and ionic strength, with higher values in the alkaline pH regions. It also depends on the seed defatting solvent. Protein solubility was decreased by using chloroform/methanol (CM) for lipid extraction instead of pentane (P). On the basis of differential solubility fractionation and depending on the defatting method, the alkali extract (AE) was the major fraction (42.1 (P), 22.3% (CM)) compared to the salt extract (8.6 (P), 7.5% (CM)). In salt, alkali, and isopropanol extracts, all essential amino acids with the exceptions of threonine and lysine met the minimum requirements for preschool children (FAO/WHO/UNU). The denaturation temperatures were 96.6 and 93.4 °C for salt and alkali extracts, respectively. Pumpkin protein extracts with unique protein profiles and higher denaturation temperatures could impart novel characteristics when used as food ingredients. PMID:23869935

  5. Arsenic fractionation in sediments of different origins using BCR sequential and single extraction methods

    International Nuclear Information System (INIS)

    The arsenic (As) contaminated sediment serves as a long-term source of arsenic because its mobility and transport in the environment are strongly influenced to associated solid phase. A single extraction method based on the reagents employed in the BCR three steps sequential extraction scheme (BCR-SES) for partitioning of arsenic (As) in sediment samples has been developed. The single-step extraction enabled a reduction of extraction times, yielding extractable contents in accordance with those obtained by application of the BCR-SES, which can be regarded as a standard method and validated by using certified reference material BCR 701. The extractable As content associated with different phases in sediment samples were analysed by electrothermal atomic absorption spectrophotometer. The extraction efficiency of As by single-step extraction was slightly higher than BCR-SES, ranged (100-104%), while difference was not significant at 95% confidence limit with <10% precision. The sediment samples from different origins varied in their physico-chemical properties and total As content. The relative mobility of As obtained from different origins was found in increasing order as: acid soluble fraction < oxidizable fraction < reducible fraction. The acid soluble fraction of As was higher in lake sediment samples as compared to those of canal and river sediments, indicating the contamination of lake ecosystem.

  6. The ultrasound-assisted aqueous extraction of rice bran oil.

    Science.gov (United States)

    Khoei, Maryam; Chekin, Fereshteh

    2016-03-01

    In this work, aqueous extraction of rice bran oil was done without and with ultrasound pretreatment. Key factors controlling the extraction and optimal operating conditions were identified. The highest extraction efficiency was found at pH=12, temperature of 45°C, agitation speed of 800rpm and agitation time of 15min, ultrasound treatment time of 70min and ultrasound treatment temperature of 25°C. Moreover, extraction yields were compared to ultrasound-assisted aqueous extraction and Soxhlet extraction. The results showed that the yield of rice bran oil at ultrasound-assisted aqueous extraction was close to the yield of oil extracted by hexane Soxhlet extraction. This result implied that the yield of rice bran oil was significantly influenced by ultrasound. With regard to quality, the oil extracted by ultrasound-assisted aqueous process had a lower content of free fatty acid and lower color imparting components than the hexane-extracted oil. Also, effect of parboiling of paddy on hexane and ultrasound-assisted aqueous extraction was studied. Both extraction methods gives higher percentage of oil from par boiled rice bran compared with raw rice bran. This may be due to the fact that parboiling releases the oil.

  7. Smiles: a fortran-77 program for sequential machine interpreted lineament extraction using digital images

    Science.gov (United States)

    Raghavan, Venkatesh; Wadatsumu, Kiyoshi; Masumoto, Shinji

    1994-03-01

    A FORTRAN-77 program Sequential Machine Interpreted Lineament Extraction System (SMILES) is presented, which is useful for automatic and manual extraction of lineament information from digital images. The SMILES is a stand-alone package composed of several modules which perform the function of image display, lineament information extraction, data management, output generation, and preliminary analysis. The program architecture and application results are described. The program has been tested using LANDSAT MSS data of southwestern Japan. The Directional Segment Detection Algorithm (DSDA) also has been applied to shaded relief maps generated from digital elevation data of the same area. Interpretation of aerial photograph stereo pairs reveals that the machine interpreted features show photogeological expressions that are characteristic of geologic lineaments.

  8. Non-cellulosic heteropolysaccharides from sugarcane bagasse - sequential extraction with pressurized hot water and alkaline peroxide at different temperatures.

    Science.gov (United States)

    Banerjee, Protibha Nath; Pranovich, Andrey; Dax, Daniel; Willför, Stefan

    2014-03-01

    The xylan-rich hemicellulose components of sugarcane bagasse were sequentially extracted with pressurized hot-water extraction (PHWE) and alkaline peroxide. The hemicelluloses were found to contain mainly arabinoxylans with varying substitutions confirmed by different chemical and spectroscopic methods. The arabinoxylans obtained from PHWE were found to be more branched compared to those obtained after alkaline extraction. Sequential extraction could be useful for the isolation of hemicelluloses with different degree of branching, molar mass, and functional groups from sugarcane bagasse, which can be of high potential use for various industrial applications.

  9. Application of a procedure of sequential extraction for the determination of metals weighed in silt of the Almendares rivers

    International Nuclear Information System (INIS)

    The study of the chemical forms of heavy metals in sediments (Solid Speciation) was done by sequential extractions. A process of 3 stages sequential extraction from Almendares River sediments was applied, to determine the specification of Cd, Cu, Ni, Pb and Zn following a protocol proposed by the Bureau Community of Reference (BCR) The relation between the percentage of metal extracted in each fraction and the contents of carbonates, manganese and iron oxides, and organic matter and silice is studied. The extracts were analyzed by flame AAE. No any matrix interference were observed

  10. Ultrasound assisted extraction of polyphenols from Punica granatum (Grenada) fruit

    International Nuclear Information System (INIS)

    Extraction of bioactive compounds from vegetable materials is a classical operation applied in many industrial processes. Few studies have made reference to processes to obtain extracts from Punica granatum. This fruit is generally consumed as such or as fermented juices. In Cuba, it is known as grenade and numerous studies have shown antiviral, antioxidant and antimicrobial properties. Maceration process is the main used technology in the preparation of extracts from Punica granatum fruit, being this a long and expensive process. Ultrasound-assisted extractions have been proven to significantly decreased extraction time and increased extraction yields in many vegetable materials. However, few papers report the use of this methodology in the extraction processes of Punica granatum. To evaluate an ultrasound-assisted extraction process to extract polyphenols from Punica granatum fruit

  11. Ultrasound-assisted extraction of pectin from sisal waste.

    Science.gov (United States)

    Maran, J Prakash; Priya, B

    2015-01-22

    In this study, an efficient ultrasound-assisted extraction (UAE) of pectin from sisal waste was investigated and optimized. Response surface methodology (RSM) based on a three-level four-factor Box-Behnken response surface design (BBD) was employed to optimize the extraction conditions (ultrasonic power, extraction temperature, extraction time and solid-liquid ratio). Analysis of variance showed that the contribution of a quadratic model was significant for the pectin extraction yield. The experimental yield (29.32%) was obtained under the optimal condition (ultrasonic power of 61 W, temperature of 50°C, time of 26 min and SL ratio of 1:28 g/ml) was well agreement with predicted values. Therefore, ultrasound-assisted extraction could be used as an alternative method to extract pectin from sisal waste with the advantages of lower extraction temperatures, shorter extraction time and reduced energy consumption.

  12. Assessment of chromium biostabilization in contaminated soils using standard leaching and sequential extraction techniques

    International Nuclear Information System (INIS)

    The iron reducing microorganism Desulfuromonas palmitatis was evaluated as potential biostabilization agent for the remediation of chromate contaminated soils. D. palmitatis were used for the treatment of soil samples artificially contaminated with Cr(VI) at two levels, i.e. 200 and 500 mg kg-1. The efficiency of the treatment was evaluated by applying several standard extraction techniques on the soil samples before and after treatment, such as the EN12457 standard leaching test, the US EPA 3060A alkaline digestion method and the BCR sequential extraction procedure. The water soluble chromium as evaluated with the EN leaching test, was found to decrease after the biostabilization treatment from 13 to less than 0.5 mg kg-1 and from 120 to 5.6 mg kg-1 for the soil samples contaminated with 200 and 500 mg Cr(VI) per kg soil respectively. The BCR sequential extraction scheme, although not providing accurate estimates about the initial chromium speciation in contaminated soils, proved to be a useful tool for monitoring the relative changes in element partitioning, as a consequence of the stabilization treatment. After bioreduction, the percentage of chromium retained in the two least soluble BCR fractions, i.e. the 'oxidizable' and 'residual' fractions, increased from 54 and 73% to more than 96% in both soils

  13. Uranium isotopic distribution in the mineral phases of granitic fracture fillings by a sequential extraction procedure

    International Nuclear Information System (INIS)

    In order to study the recent rock-water interaction processes in the El Berrocal site, a sequential leaching method has been applied to granitic fracture fillings to obtain the U isotopic distribution in the mineral phases of these samples. Based on the mineralogical composition of these materials, six dissolution steps have been chosen to extract U as exchangeable cation, from carbonates, amorphous Fe-oxyhydroxides, labile resistates and highly insoluble resistates. In this way, the processes involved in the rock-water interaction phenomena, mainly dissolution, precipitation, coprecipitation and adsorption can be distinguished and even approximately dated. (author)

  14. Operationally defined availability from sequential extractions compared to plant uptake of 137Cs and 90Sr

    International Nuclear Information System (INIS)

    The operationally defined bioavailable fraction from a commonly used sequential extraction (SE) procedure was compared to biological availability represented by plant uptake of 137Cs and 90Sr. Experiments were conducted at two locations in the Ukraine and at several field locations on the Savannah River Site, South Caroline. A significant regression existed between plant uptake and the ammonium acetate fraction (r2=0.65), however, ratios of predicted uptake from the SE procedure to observed plant uptake ranged from 0.03 to 5.2. Data suggest that the SE procedure was useful for qualitative interpretations of biological availability but lacked sufficient rigor to be useful for quantitative predictions. (author)

  15. A comparison between heavy metals released from soil and its efficient speciation extracted by sequential extraction procedure

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui

    2008-01-01

    A simulating experiment was carried out on the interaction between natural precipitation and soil. The results demonstrated that the contents of heavy metals (V, Co, Cr, and Ni) released from soil into the solution under Earth's surface conditions are higher than the contents of those metals bonded to exchangeable species, which were extracted by sequential extraction procedure recommended by Tessier and others in 1979. It is demonstrated that the metals bonded to other 3 species (carbonate, Fe-Mn oxide, and organic matter) except those bonded to the exchangeable species in efficient speciation can be released under the Earth's surface conditions, when pH=4 in the reaction system, and the higher correlation coefficient indicated that the concentrations of heavy metals released from soil into the solution vary approximately with reaction time in terms of index regulations.

  16. Determination and Fractionation of heavy Metals in Sediments from Yarmouk River, Jordan by Sequential Extraction

    International Nuclear Information System (INIS)

    The fractionation of the eight metals Pb, Ni, Zn, Co, Cr, Mn, Fe and Cd in Yarmouk River were determined by applying a sequential extraction procedure. The potential environmental impacts of the metals estimated through the five extraction categories, that's exchangeable, bound to carbonate, bound to Fe/Mn oxides, bound to organic matter and the residual. The results show that the sediments of the Yarmouk River would be moderately to heavily polluted fluvial systems in the region. The observed metal distribution patterns in the different sediment fractions, however, indicated that the major proportions of most metals seemed to be associated with the residual fraction which consists essentially of detrital silicate minerals, resistant sulfides, and a small quantity of refractory organic material that could therefore be classified to be of geochemical origin. (Author's) 14 refs., 4 tabs., 4 figs

  17. Study on geochemical association of plutonium in soil using sequential extraction procedure

    International Nuclear Information System (INIS)

    Three kinds of soil, collected in various places (in northwestern and southeastern Poland and near Chernobyl) were used as a subject of sequential extraction and plutonium distribution study. The modified method of TESSIER was applied to separate readily available, carbonate, organic, Fe/Mn oxide and residual fractions. Plutonium isotope activity in soil as well as in particular separated fractions was determined by means of alpha spectrometry. The method of plutonium separation and purification for alpha-spectrometric measurements was modified according to the chemical properties of the extracted fraction. It was found that the major part (about 90%) of 239,240Pu is bound to organic and Fe/Mn oxide fractions (in uncultivated soil samples of northwestern Poland and Chernobyl). In soil samples coming from river valley (southeastern Poland) almost equal amounts of plutonium are distributed between the available, organic and residual fractions. (author)

  18. Heavy Metal and Trace Metal Analysis in Soil by Sequential Extraction: A Review of Procedures

    Directory of Open Access Journals (Sweden)

    Amanda Jo Zimmerman

    2010-01-01

    Full Text Available Quantification of heavy and trace metal contamination in soil can be arduous, requiring the use of lengthy and intricate extraction procedures which may or may not give reliable results. Of the many procedures in publication, some are designed to operate within specific parameters while others are designed for more broad application. Most procedures have been modified since their inception which creates ambiguity as to which procedure is most acceptable in a given situation. For this study, the Tessier, Community Bureau of Reference (BCR, Short, Galán, and Geological Society of Canada (GCS procedures were examined to clarify benefits and limitations of each. Modifications of the Tessier, BCR, and GCS procedures were also examined. The efficacy of these procedures is addressed by looking at the soils used in each procedure, the limitations, applications, and future of sequential extraction.

  19. Molecular Characteristics of Kraft-AQ Pulping Lignin Fractionated by Sequential Organic Solvent Extraction

    Directory of Open Access Journals (Sweden)

    Kun Wang

    2010-08-01

    Full Text Available Kraft-AQ pulping lignin was sequentially fractionated by organic solvent extractions and the molecular properties of each fraction were characterized by chemical degradation, GPC, UV, FT-IR, 13C-NMR and thermal analysis. The average molecular weight and polydispersity of each lignin fraction increased with its hydrogen-bonding capacity (Hildebrand solubility parameter. In addition, the ratio of the non-condensed guaiacyl/syringyl units and the content of β-O-4 linkages increased with the increment of the lignin fractions extracted successively with hexane, diethylether, methylene chloride, methanol, and dioxane. Furthermore, the presence of the condensation reaction products was contributed to the higher thermal stability of the larger molecules.

  20. Uranium distribution in mineral phases of rock by sequential extraction procedure

    International Nuclear Information System (INIS)

    A sequential extraction procedure was used to study the distribution of uranium in mineral phases of rock at the Koongarra uranium deposit (Northern Territory of Australia). This work forms a part of the natural analogue study carried out in the International Alligator Rivers Analogue Project, which is being sponsored by the OECD/NEA. The following mineral phases: adsorbed trace material and carbonate minerals, amorphous iron minerals and secondary uranium minerals, crystalline iron minerals, clay minerals, and remaining resistant mineral phases, were extracted successively by treatment with: 1 M sodium acetate (pH=5) (Morgan's solution). Tamm's acid oxalate (TAO) (pH=3), citrate-dithionite-bicarbonate (CDB), 6 M hydrochloric acid, and fusion respectively. The majority of uranium in samples from the secondary ore body at Koongarra was contained in crystalline iron minerals (42-60%). In the primary or body, the uranium distribution between mineral phases varies with depth. About 70% of the total uranium was incorporated with the Tamm's extractable mineral phases, in the weathered region of the drill hole DDH1 (19.4-20.5 m). In the deeper region of the drill hole DDH2 (33.0-34.3 m), most of the uranium was extractable with 6 M HCl. The 234U/238U activity ratios in each extraction are discussed on the basis of the alpha recoil effect, which occurs with the decay of 238U through 234Th to 234U. (orig.)

  1. Element fractionation by sequential extraction in a soil with high carbonate content

    International Nuclear Information System (INIS)

    The influence of carbonate and other buffering substances in soils on the results of a 3-step sequential extraction procedure (BCR) used for metal fractionation was investigated. Deviating from the original extraction scheme, where the extracts are analysed only for a limited number of metals, almost all elements in the soils were quantified by X-ray fluorescence spectroscopy, in the initial samples as well as in the residues of all extraction steps. Additionally, the mineral contents were determined by X-ray diffractometry. Using this methodology, it was possible to correlate changes in soil composition caused by the extraction procedure with the release of elements. Furthermore, the pH values of all extracts were monitored, and certain extraction steps were repeated until no significant pH-rise occurred. A soil with high dolomite content (27%) and a carbonate free soil were extracted. Applying the original BCR-sequence to the calcareous soil, carbonate was found in the residues of the first two steps and extract pH-values rose by around two units in the first and second step, caused mainly by carbonate dissolution. This led to wrong assignment of the carbonate elements Ca, Mg, Sr, Ba, and also to decreased desorption and increased re-adsorption of ions in those steps. After repetition of the acetic acid step until extract pH remained low, the carbonate was completely destroyed and the distributions of the elements Ca, Mg, Sr, Ba as well as those of Co, Ni, Cu, Zn and Pb were found to be quite different to those determined in the original extraction. Furthermore, it could be shown that the effectiveness of the reduction process in step two was reduced by increasing pH: Fe oxides were not significantly attacked by the repeated acetic acid treatments, but a 10-fold amount of Fe was mobilized by hydroxylamine hydrochloride after complete carbonate destruction. On the other hand, only small amounts of Fe were released anyway. Even repeated reduction steps did not

  2. Selectivity assessment of an arsenic sequential extraction procedure for evaluating mobility in mine wastes

    International Nuclear Information System (INIS)

    Highlights: • Extraction efficiency and selectivity of phosphate and oxalate were tested. • Pure As-bearing mineral phases and mine wastes were used. • The reagents were found to be specific and selective for most major forms of As. • An optimized sequential extraction scheme for mine wastes has been developed. • It has been tested over a model mineral mixtures and natural mine waste materials. - Abstract: An optimized sequential extraction (SE) scheme for mine waste materials has been developed and tested for As partitioning over a range of pure As-bearing mineral phases, their model mixtures, and natural mine waste materials. This optimized SE procedure employs five extraction steps: (1) nitrogen-purged deionized water, 10 h; (2) 0.01 M NH4H2PO4, 16 h; (3) 0.2 M NH4-oxalate in the dark, pH3, 2 h; (4) 0.2 M NH4-oxalate, pH3/80 °C, 4 h; (5) KClO3/HCl/HNO3 digestion. Selectivity and specificity tests on natural mine wastes and major pure As-bearing mineral phases showed that these As fractions appear to be primarily associated with: (1) readily soluble; (2) adsorbed; (3) amorphous and poorly-crystalline arsenates, oxides and hydroxosulfates of Fe; (4) well-crystalline arsenates, oxides, and hydroxosulfates of Fe; as well as (5) sulfides and arsenides. The specificity and selectivity of extractants, and the reproducibility of the optimized SE procedure were further verified by artificial model mineral mixtures and different natural mine waste materials. Partitioning data for extraction steps 3, 4, and 5 showed good agreement with those calculated in the model mineral mixtures (<15% difference), as well as that expected in different natural mine waste materials. The sum of the As recovered in the different extractant pools was not significantly different (89–112%) than the results for acid digestion. This suggests that the optimized SE scheme can reliably be employed for As partitioning in mine waste materials

  3. Kriging analysis of geochemical data obtained by sequential extraction procedure (BCR)

    Science.gov (United States)

    Fajkovic, Hana; Pitarević Svedružić, Lovorka; Prohić, Esad; Rončević, Sanda; Nemet, Ivan

    2015-04-01

    Field examination and laboratory analysis were performed to establish whether nonsanitary landfill Bastijunski brig has a negative influence on Vransko Lake, situated only 1500 m away. Vransko Lake is Croatia's largest natural lake, and it is a part of the Nature Park and ornithological reserve, which indicates its high biodiversity. Therefore it is necessary to understand the environmental processes and complex sediment/water interface. Lake sediments are considered to be a good "sinkhole'and are often the final recipients of anthropogenic and natural pollutants through adsorption onto the organic or clay fraction in sediments. Geochemical investigation were obtained throughout more than 50 lake sediments cores situated in different parts of the lake Speciation of heavy metals by modified BCR sequential extraction procedure with the addition of a first step of sequential extraction procedure by Tessier and analysis of residual by aqua regia were used to determine the amounts of selected elements (Al, Cd, Cr, Co, Cu, Fe, Mn, Ni, Pb, Zn) in different fractions. With such approach it is possible to determine which element will be extracted from sediment/soil in a different environmental conditions and can be valuable tool for interpretation of the mobile fraction of the elements, considered bioavailability, that present threat to biota in a case of a contaminant concentration magnification. All sediment and soil samples were analyzed by inductively coupled plasma atomic emission spectrometry. More accurate interpretation of data is an advantage of BCR sequential extraction procedure while high number of the data together with point data type could be considered as a drawback. Due to high amount of data, graphical presentation is advisable while interpolation tool is a first choice for point type of data, as it makes predictions for defined area based on the measurements. Distribution maps of analysed elements were obtained by kriging as a geostatistical method and

  4. Solid phase speciation of arsenic by sequential extraction in standard reference materials and industrially contaminated soil samples

    Energy Technology Data Exchange (ETDEWEB)

    Herreweghe, Samuel van; Swennen, Rudy; Vandecasteele, Carlo; Cappuyns, Valerie

    2003-04-01

    Leaching experiments, a mineralogical survey and larger samples are preferred when arsenic is present as discrete mineral phases. - Availability, mobility, (phyto)toxicity and potential risk of contaminants is strongly affected by the manner of appearance of elements, the so-called speciation. Operational fractionation methods like sequential extractions have been applied for a long time to determine the solid phase speciation of heavy metals since direct determination of specific chemical compounds can not always be easily achieved. The three-step sequential extraction scheme recommended by the BCR and two extraction schemes based on the phosphorus-like protocol proposed by Manful (1992, Occurrence and Ecochemical Behaviours of Arsenic in a Goldsmelter Impacted Area in Ghana, PhD dissertation, at the RUG) were applied to four standard reference materials (SRM) and to a batch of samples from industrially contaminated sites, heavily contaminated with arsenic and heavy metals. The SRM 2710 (Montana soil) was found to be the most useful reference material for metal (Mn, Cu, Zn, As, Cd and Pb) fractionation using the BCR sequential extraction procedure. Two sequential extraction schemes were developed and compared for arsenic with the aim to establish a better fractionation and recovery rate than the BCR-scheme for this element in the SRM samples. The major part of arsenic was released from the heavily contaminated samples after NaOH-extraction. Inferior extraction variability and recovery in the heavily contaminated samples compared to SRMs could be mainly contributed to subsample heterogeneity.

  5. Solid phase speciation of arsenic by sequential extraction in standard reference materials and industrially contaminated soil samples

    International Nuclear Information System (INIS)

    Leaching experiments, a mineralogical survey and larger samples are preferred when arsenic is present as discrete mineral phases. - Availability, mobility, (phyto)toxicity and potential risk of contaminants is strongly affected by the manner of appearance of elements, the so-called speciation. Operational fractionation methods like sequential extractions have been applied for a long time to determine the solid phase speciation of heavy metals since direct determination of specific chemical compounds can not always be easily achieved. The three-step sequential extraction scheme recommended by the BCR and two extraction schemes based on the phosphorus-like protocol proposed by Manful (1992, Occurrence and Ecochemical Behaviours of Arsenic in a Goldsmelter Impacted Area in Ghana, PhD dissertation, at the RUG) were applied to four standard reference materials (SRM) and to a batch of samples from industrially contaminated sites, heavily contaminated with arsenic and heavy metals. The SRM 2710 (Montana soil) was found to be the most useful reference material for metal (Mn, Cu, Zn, As, Cd and Pb) fractionation using the BCR sequential extraction procedure. Two sequential extraction schemes were developed and compared for arsenic with the aim to establish a better fractionation and recovery rate than the BCR-scheme for this element in the SRM samples. The major part of arsenic was released from the heavily contaminated samples after NaOH-extraction. Inferior extraction variability and recovery in the heavily contaminated samples compared to SRMs could be mainly contributed to subsample heterogeneity

  6. Sequential injection 90Sr determination in environmental samples using a wetting-film extraction method.

    Science.gov (United States)

    Miró, Manuel; Gómez, Enrique; Estela, José Manuel; Casas, Montserrat; Cerdà, Victor

    2002-02-15

    A sequential injection procedure involving a flow-reversal wetting-film extraction method for the determination of the radionuclide 90Sr has been developed. The methodology is based on the coating of the inner walls of an open tubular reactor with a film prepared from a 0.14 M 4,4'(5')-bis(tert-butylcyclohexano)-18-crown-6 (BCHC) solution in 1-octanol, which allows the selective isolation of strontium from the sample matrix. Selection of the optimum extractant diluent attending its physical properties, investigation of the extraction kinetics features, and choice of the proper elution procedure are discussed in detail in this paper. The noteworthy aspects of using a wetting-film phase instead of a solid-phase material described to date in the literature are the reduction of crown ether consumption and the simplification of both the operational sequence and the automation of the extractant-phase renewal between consecutive samples, which is of interest to avoid analyte carryover and reduction of the resin capacity factor caused by irreversible interferences. The proposed method has been successfully applied to different spiked environmental samples (water, milk, and soil), with 90Sr total activities ranging between 0.07 and 0.30 Bq, measured using a low-background proportional counter. The standard deviation of the automated analytical separation procedure is lower than 3% (n = 10), and the 90Sr isolation process under the studied conditions may be carried out with a yield up to 80%.

  7. Uranium distribution in mineral phases or rocks by a five phase sequential extraction procedure

    International Nuclear Information System (INIS)

    Sequential extraction techniques are used to measure the fractionation of uranium and thorium series nuclides in iron/clay/quartz phases etc. as part of the uranium/thorium desequilibria database preparation and understand how the two (or more) separated phases are related to the ore minerals and their accessibility to groundwater. Samples have been characterized for elemental associations and mineralogical distributions. Special attention was given to those elements which have particular significance for the geochemical modelling including species such as phosphate. In the secondary ore body, crystalline iron minerals such as limonite and pyrite appear as the significant mineral phase associated with uranium accumulation. The Morgan's and Tamm's solution extractable minerals (adsorbed and carbonate, and amorphous iron minerals respectively) are accessible to groundwater and so their 234U/238U activity ratios, less than unity, are equal to that of the groundwater. The remaining resistant minerals (mainly quartz) are the significant mineral phase found to be enrich with 234U by the alpha recoil effect. However, in the shallow region of the primary ore body, the Tamm's solution extractable minerals (secondary uranium minerals such as autunite and torbernite - uranyl phosphates) are the significant mineral phase associated with the uranium accumulation. In the deeper region of the primary ore body, the 6 M HCl extractable minerals (clay and some refactory minerals) seems to be predominant. 5 refs., 1 tab., 3 figs

  8. Development of a sequential extraction method for different forms of phosphorus in Bovilla lake sediments

    Directory of Open Access Journals (Sweden)

    Loreta Vallja

    2013-12-01

    Full Text Available Extractable forms of phosphorus are studied more widely than the extractable forms of most other elements. The main reason for this is because P is the key element in aquatic chemistry of lakes being a limiting nutrient in the growth of algae under many conditions. Exchange with bottom sediments place an important role in making P available for algae and contributes, therefore to eutrophication. Many extraction schemes have been developed to determine different forms of P in sediments. The objective of the present study was to estimate the bioavailability/mobility of phosphate from Bovilla lake sediments using a sequential extraction procedure and to evaluate their possible contributions to the P-loadings the lake. Results for three stations of Bovilla Lake are presented. A relatively high total phosphorus content of 452 mg/kg DW have been found in sediment samples taken from three sites of Bovilla Lake. This shows an important potential of sediments to release the P compounds, especially under anoxic conditions.

  9. Ultrasound-Assisted Extraction of Stilbenes from Grape Canes.

    Science.gov (United States)

    Piñeiro, Zulema; Marrufo-Curtido, Almudena; Serrano, Maria Jose; Palma, Miguel

    2016-01-01

    An analytical ultrasound-assisted extraction (UAE) method has been optimized and validated for the rapid extraction of stilbenes from grape canes. The influence of sample pre-treatment (oven or freeze-drying) and several extraction variables (solvent, sample-solvent ratio and extraction time between others) on the extraction process were analyzed. The new method allowed the main stilbenes in grape canes to be extracted in just 10 min, with an extraction temperature of 75 °C and 60% ethanol in water as the extraction solvent. Validation of the extraction method was based on analytical properties. The resulting RSDs (n = 5) for interday/intraday precision were less than 10%. Furthermore, the method was successfully applied in the analysis of 20 different grape cane samples. The result showed that grape cane byproducts are potentially sources of bioactive compounds of interest for pharmaceutical and food industries. PMID:27322224

  10. Optimization of enzyme assisted extraction of polysaccharides from Ganoderma lucidum

    Institute of Scientific and Technical Information of China (English)

    Xu Chunhua; Tian Zhenle; Zhang Chenju; Yu Xiaobing; Zheng Huihua

    2014-01-01

    In the present work,an enzyme assisted extraction method is used to isolate crude polysaccharides from Ganoderma lucidum. The isolating effect was optimized with orthographic graph statistic method with three levels and four independent variables. Complex enzyme,extraction temperature,extraction time and ex-traction pH were combined to obtain the best possible combination to get maximum amount of extract and crude polysaccharides yield. The optimum extraction conditions were:complex enzyme amount of 3%(w/v),extrac-tion temperature at 45℃,extraction time of 3 h and extraction pH at 7. Under these conditions,the experimen-tal amount of extract is 8.9%and the yield of crude polysaccharides is 1.1%,which are in close agreement with the value predicted by the model.

  11. A sequential extraction and hydrolysis approach to understand the chemical nature of soil water repellency

    Science.gov (United States)

    Mao, Jiefei; Dekker, Stefan C.; Nierop, Klaas G. J.

    2014-05-01

    Soil water repellency (SWR) biomarkers (SWR-biomarkers) are defined as hydrophobic organic compounds in soils causing SWR and originating from vegetation or microbes (Doerr et al., 2000). Free lipids and ester-bound biopolymers (cutins and suberins) are usually seen in the aliphatic part of soil organic matter (SOM) (Nierop, 1998). The method of sequential extraction can divide hydrophobic compounds into individual fractions with different characteristics. We aim to find out the SWR-biomarkers in soils within different fractions, investigate the effects of fractions on SWR and link them to their original sources. To extract free and ester-bound lipids from sandy soils, DCM (dichloromethane)/MeOH (methanol) and IPA(isopropanol)/NH3 were used in sequential steps. As a result, three fractions were obtained during these sequential experiments: a DCM/MeOH soluble fraction (D), a DCM-MeOH soluble (AS) fraction of IPA/NH3 extracts and its insoluble (AI) fraction. To date, research was limited to (organic) extractable fractions only. To investigate the DCM-MeOH insoluble part of IPA/NH3 extracts they were depolymerised by trans-methylation using BF3-MeOH. All fractions were analysed by gas chromatography-mass spectrometry. After DCM/MeOH extraction, water repellency of 80% of the soils studied increased while SWR of the other soils remained at the same level. Straight-chain fatty acids, alcohols and alkanes were the main compound groups in the D fractions. The distribution of fatty acids (C20-C32) and alcohols (C20-C32), both of which with an even-over-odd predominance suggest their source were higher plants, and so did the odd-over-even predominated alkanes. After extraction by IPA/NH3 , most soils became non-repellent. Both fatty acids (C16-C32) and alcohols (C16-C30) with an even-over-odd predominance were also found in the AS fractions, whereas no alkanes were detected. There were four main component groups identified in the AI fractions: fatty acids, alcohols,

  12. The ultrasound assisted extraction of matrix elements and heavy metal fractions associated with Fe, Al and Mn oxyhydroxides from soil

    Directory of Open Access Journals (Sweden)

    Stanišić Svetlana M.

    2012-01-01

    Full Text Available The single agent extractions of major and trace metals from soil sample were conducted by means of rotary mixer and ultrasonic bath with sonication time of 10, 20, 30, 40 and 50 min. The sequential extraction according to the BCR scheme was undertaken. The obtained soil extracts were analyzed by ICP-OES and according to the results the rotary mixer assisted extraction was more efficient in the case of alkaline-earth elements. However, by the use of ultrasound several times higher amounts of matrix elements (Fe, Al and Mn and heavy metals predominantly associated with Fe, Al and Mn oxyhydroxides were extracted. The increase of the sonication time failed to improve extraction yields. The changes of the conductivity, pH, oxidoreduction potential, particle size diameter and zeta potential of colloid particles, with the sonication time increase were measured. The extraction mechanism and expressed selectivity of ultrasound is discussed and explanation is suggested.

  13. Evaluation of the BCR sequential extraction procedure applied for two unpolluted Spanish soils

    International Nuclear Information System (INIS)

    The procedure of BCR sequential extraction has been applied to five samples from two unpolluted soils in southern Spain. Total concentrations of different elements have been calculated as the sum of the three fractions of BCR and the residue has been measured for each. Also, a total analysis based on INAA or total-digestion techniques has been performed for the same samples. BCR and total analysis closely agreed for As, Pb and Cd. For Cu, Co, Cr and Zn the comparison of the results did not provide definitive conclusions concerning the capability of BCR in measuring total concentrations. On the other hand, in these cases, a certain correlation was found between the concentrations measured and some soil characteristics, especially the clay, organic-matter and CaCO3 contents. BCR proved incapable of providing accurate measurements for Ni

  14. A study on radionuclide association with soil components using a sequential extraction procedure

    International Nuclear Information System (INIS)

    Measurements performed in 1986-1988 demonstrate that most of the radiocesium isotopes (137Cs and 134Cs) deposited after the Chernobyl accident are still located in the upper soil layers (0-2 cm). Sequential extraction techniques have been utilized in order to investigate the degree of binding or association between deposited radionuclides (137Cs, 134Cs and 90Sr) and components in soil. The results indicate that a major fraction of the radiocesium is associated strongly with organic and mineral materials in the litter or upper soil layers: less than 10% is easily leachable. For 90Sr, the results show a relatively high leachable fraction. It is concluded that radiocesium should be less mobile, and less available for root uptake, than 90Sr in soil. (author) 9 refs.; 4 figs.; 1 tab

  15. Investigations of Cu, Pb and Zn partitioning by sequential extraction in harbour sediments after electrodialytic remediation

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2010-01-01

    Electrodialytic remediation was used to remove Cu, Zn and Pb from three different contaminated harbour sediments. Electrodialytic experiments lasting 2 and 4 weeks were performed and 48-86% Cu, 74-90% Zn and 62-88% Pb were removed from the different sediments and the removal increased with longer...... remediation time. A three step sequential extraction scheme (BCR), with an extra residual step, was used to evaluate the heavy metal distribution in the sediments before and after electrodialytic remediation. Cu was mainly associated with the oxidisable phase of the sediment, both before and after remediation....... Zn and Pb were found in the exchangeable and reducible phases before remediation. Zn was still found in the exchangeable and reducible phases after remediation, whereas most Pb was removed from these phases during electrodialytic remediation....

  16. Sequential Chomospheric Brightening: An Automated Approach to Extracting Physics from Ephemeral Brightening

    CERN Document Server

    Kirk, Michael S; Jackiewicz, Jason; McAteer, R T James; McNamara, Bernie J

    2012-01-01

    We make a comparison between small scale chromospheric brightenings and energy release processes through examining the temporal evolution of sequential chromospheric brightenings (SCBs), derive propagation velocities, and propose a connection of the small-scale features to solar flares. Our automated routine detects and distinguishes three separate types of brightening regularly observed in the chromosphere: plage, flare ribbon, and point brightenings. By studying their distinct dynamics, we separate out the flare-associated bright points commonly known as SCBs and identify a propagating Moreton wave. Superimposing our detections on complementary off-band images, we extract a Doppler velocity measurement beneath the point brightening locations. Using these dynamic measurements, we put forward a connection between point brightenings, the erupting flare, and overarching magnetic loops. A destabilization of the pre-flare loop topology by the erupting flare directly leads to the SCBs observed.

  17. Assessment of a sequential extraction protocol by examining solution chemistry and mineralogical evolution

    Science.gov (United States)

    Maubec, Nicolas; Pauwels, Hélène; Noël, Hervé; Bourrat, Xavier

    2015-04-01

    Knowledge of the behavior of heavy metals, such as copper and zinc in sediments, is a key factor to improve the management of rivers. The mobility of these metals, which may be harmful to the environment, depends directly on their concentration and speciation , which in turn depend on physico-chemical parameters such as mineralogy of the sediment fraction, pH, redox potential, salinity etc ... (Anderson et al., 2000; Sterckeman et al., 2004; Van Oort et al., 2008). Several methods based on chemical extractions are currently applied to assess the behavior of heavy metals in soils and sediments. Among them, sequential extraction procedure is widely used in soil and sediment science and provides details about the origin, biological and physicochemical availability, mobilization and transports of trace metals elements. It is based on the use of a series of extracting reagents to extract selectively heavy metals according to their association within the solid phase (Cornu and Clozel, 2000) including the following different fraction : exchangeable, bound to carbonates, associated to oxides (reducible fraction), linked to organic matter and sulfides (oxidizable fraction) as well as silicate minerals so called residual fraction (Hickey and Kittrick, 1984; Tessier et al., 1979). Consequently sequential extraction method is expected to simulate a lot of potential natural and anthropogenic modifications of environmental conditions (Arey et al., 1999; Brannon and Patrick, 1987; Hickey and Kittrick, 1984; La Force et al., 1999; Tessier et al., 1979). For three decades, a large number of protocols has been proposed, characterized by specific reagents and experimental conditions (concentrations, number of steps, extraction orders and solid/solution ratio) (Das et al., 1995; Gomez Ariza et al., 2000; Quevauviller et al., 1994; Rauret, 1998; Tack and Verloo, 1995), but it appeared that several of them suffer from a lack of selectivity of applied reagents: besides target ones, some

  18. Evaluation of dissipation gradients of polycyclic aromatic hydrocarbons in rice rhizosphere utilizing a sequential extraction procedure

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the spatial dissipation gradient of PAHs, including phenanthrene, pyrene, and benzo[a]pyrene, with various bioavailability represented with sequential extraction. Dissipation rates of PAHs in the rhizosphere were greater than those in the bulk soil. The n-butanol extracted fraction showed a general trend of dissipation during phytoremediation. Moreover, the formation of bound PAH residues was inhibited in the rhizosphere. While concerning the PAH toxicity, the reduction rates of PAH toxicity were significantly greater than total soil PAH concentrations. Microbial biomass was the highest at four mm away from the root surface. However, the PAH dissipation rates were the highest at one mm and two mm away from the root surface in high and low PAH treatments, respectively. These results suggest that rhizoremediation with rice is a useful approach to reduce the toxicity of PAHs in soil. - Highlights: ► Dissipation gradients were different in soils spiked with different PAHs concentrations. ► Butanol extracted fraction indicated the remediation in rhizosphere. ► Toxicity of PAHs was more efficiently reduced than total concentration. ► Promotion of PAHs degraders was not synchronized with microbial biomass. - Stimulation of PAH degradation in rice rhizosphere was not simultaneous with microbial biomass.

  19. SEQUENTIAL EXTRACTION OF PHOSPHORUS BY MEHLICH-1 AND ION EXCHANGE RESIN FROM B HORIZONS OF FERRIC AND PERFERRIC LATOSOLS (OXISOLS

    Directory of Open Access Journals (Sweden)

    Danilo de Lima Camêlo

    2015-08-01

    Full Text Available In general, Latosols have low levels of available P, however, the influence of the parent material seems to be decisive in defining the pool and predominant form of P in these soils. This study evaluated P availability by extraction with Mehlich-1 (M-1 and Ion Exchange Resin (IER, from samples of B horizons of Ferric and Perferric Latosols developed from different parent materials. To this end, in addition to the physical and chemical characterization of soils, 10 sequential extractions were performed with M-1 and IER from samples of B horizons (depth between 0.8 and 1.0 m. Total contents of Ca, P, Fe, Al, and Ti were determined after digestion with nitric, hydrofluoric and perchloric acids. The effects of sequential P extractions on Fe oxides were also evaluated from the analyses of dithionite-citrate-bicarbonate and ammonium acid oxalate. The high similarity between contents of P accumulated after sequential extractions with M-1 and IER in soils developed on tuffite indicated a predominance of P-Ca. Higher contents of P after a single IER extraction show greater efficiency in P removal from highly weathered soils, as from the Latosols studied here. The P contents also show the high sensitivity of extractant M-1 in highly buffered soils. Furthermore, a single extraction with extractant M-1 or IER is not sufficient to estimate the amount of labile P in these soils.

  20. BCR-701: A review of 10-years of sequential extraction analyses

    International Nuclear Information System (INIS)

    A detailed quantitative analysis was performed on data presented in the literature that focused on the sequential extraction of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) from the certified reference material BCR-701 (lake sediment) using the three-step harmonized BCR procedure. The accuracy of data reported in the literature, including precision and different measures of trueness, was assessed relative to the certified values for BCR-701. Forty data sets were accepted following extreme outlier removal, and statistically summarized with measures of central tendency, dispersion, and distribution form. In general, literature data were similar in their measurement precision to the expert laboratories used to certify the trace element contents in BCR-701. The overall median precision for literature reported data was 10% (range 6-19%), compared to certifying laboratories of 9% (range 4-33%). One measure of literature data trueness was assessed via a confirmatory approach using a robust bootstrap method. Only 22% of the comparisons indicated significantly different (all were lower) concentrations reported in the literature compared to certified values. The question of whether the differences are practically significant for environmental studies is raised. Bias was computed as a measure of trueness, and literature data were more frequently negatively biased, indicating lower concentrations reported in the literature for the six trace elements for the three-step sequential procedure compared to the certified values. However, 95% confidence intervals about the average bias for the 18 comparisons indicated only four instances when a mean bias of 0 (i.e., measured = certified) was not incorporated-suggesting statistical difference. Finally, Z-scores incorporating a Horwitz-type function were used to assess the general trueness of laboratory data. Of the 468 laboratory Z-score values computed, 92% were considered to be satisfactory, 5% were

  1. Assessment of lead distribution in aquatic plant Lemna minor, using sequential extraction procedure

    International Nuclear Information System (INIS)

    Complete text of publication follows. The contamination of water resources by toxic metals demands for attention since this kind of contamination, sometimes, is difficult to realize. Moreover, lead, for instance, has the capacity to be accumulated in fish and plants utilized in the food, and also in human beings, causing several disturbances. Phytoremediation is an emerging technology that employs the use of plants for the clean-up of contaminated environments. The model plant Lemna minor is a genera of Duckweed plant, and refers to a group of floating, flowering plants of the family Lemnaceae. The aquatic plant Lemna minor is relevant to many aquatic environments, including lakes, streams, effluent, rain, and sediment. The aquatic plant Lemna minor has been studied due its potential to extract lead from contaminated waters. The aim of this study was to determine the distribution of Pb in the aquatic plant Lemna minor under stress, using a modified sequential extraction with different solvents: hexane, ethyl acetate, 2-propanol, methanol, ethanol/water (1:1) and water. Non-extractable residues formed the last fraction. Elemental distributions in the plants were determined using flame atomic absorption spectroscopy (F AAS), and scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDX). It was found that the aquatic plant L. minor has the capacity to accumulate lead: in the first day of contamination, about 79% of lead had been intake by the plant. After 7 days, the Pb content was 142 mg Kg-1. After sequential extraction, the methanol and ethanol/water fractions were dominants: 27 and 45% of total content, respectively. In these fractions we can find acids that form specific chelating agents, such as oligopeptides (phytochelatins). The hexane, ethyl acetate, and 2-propanol fractions gave the smallest isolated fraction. These fractions consisted of non-polar lipid compounds. Elemental distribution by X-ray fluorescence spectra and maps

  2. Ontology Assisted Formal Specification Extraction from Text

    Directory of Open Access Journals (Sweden)

    Andreea Mihis

    2010-12-01

    Full Text Available In the field of knowledge processing, the ontologies are the most important mean. They make possible for the computer to understand better the natural language and to make judgments. In this paper, a method which use ontologies in the semi-automatic extraction of formal specifications from a natural language text is proposed.

  3. Comparison of two sequential extraction procedures for uranium fractionation in contaminated soils

    International Nuclear Information System (INIS)

    Two sequential extraction procedures were carried out on six soils with different chemical properties and contamination history to estimate the partitioning of uranium (U) between different soil fractions. The first standard method (method of Schultz) was specifically developed for actinides, while the second one (method of Rauret) was initially created for heavy metals. Reproducibility of both methods was compared by means of the coefficient of variation (CV). A soil-to-plant transfer experiment was also carried out with ryegrass to verify if one of the extracted fractions efficiently predicted plant uptake. In artificially contaminated soils, most of the U was retrieved from the exchangeable and the carbonates fractions. In soils with high natural levels of U or contaminated by industrial activity, most of the U was found in the less available fractions. Different U concentrations were found in the fractions which were supposed to be comparable in the two methods. Extracted fractions following Schultz differentiated more strongly between the tested soils but no relationships with soil parameters could be established. As expected, the highest U transfer factors (TF) were observed for ryegrass grown on artificially contaminated soils and the lowest on soils with high natural concentrations or industrial contamination, in agreement with the extraction procedures. No good relation was found between the soil-to-shoot TF and the extracted U concentrations. On the other hand, the U concentration in the roots, the U concentration in the shoots and the soil-to-root TF are well correlated to the U concentration determined in the first extracted fractions (so called exchangeable fractions) from the method of Schultz. We conclude that the extraction method according to Schultz should be preferably used for U, and that the exchangeable fraction can be proposed as a potential indicator to evaluate plant uptake in soils. - Highlights: • U in exchangeable and carbonate

  4. Sequential method for the assessment of innovations in computer assisted industrial processes

    International Nuclear Information System (INIS)

    A sequential method for the assessment of innovations in industrial processes is proposed, using suitable combinations of mathematical modelling and numerical simulation of dynamics. Some advantages and limitations of the proposed method are discussed. tabs

  5. Sequential Extraction and Spectroscopic Characterisation of Organic Matter from the Callovo-Oxfordian Formation

    Energy Technology Data Exchange (ETDEWEB)

    Grasset, L.; Brevet, J; Schäfer, T; Claret, F; Gaucher, E; Albrecht, A; Amblès, A

    2010-01-01

    One site under consideration for the disposal of medium and high level, long lived radioactive waste is in the eastern part of the Paris Basin (Meuse/Haute Marne, France), where the National Radioactive Waste Management Agency (ANDRA) operates an underground laboratory. The sedimentary host formation is a 130 m thick, clay-rich Callovo-Oxfordian deposit ca. 350-550 m below ground in the selected area. The major fraction (>95%) of the organic matter (OM) is associated with minerals. In order to better understand the importance of OM on the chemistry of this formation, we have developed a protocol allowing extraction/fractionation of organic compounds in the rocks. The protocol is based on classical methods currently used for the isolation of humic substances from soils and for the separation of kerogen in ancient sediments using sequential extraction with solvents and water at different pH value. This allows us to the remove a large part of the minerals and to suspend almost all (>90%) of the OM (associated with residual recalcitrant minerals) in water. The OM can then be analysed via spectroscopic methods, such as mass spectrometry (MS), Fourier transform infra-red spectroscopy (FTIR), or C (1s) near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The molecular composition of the solvent-soluble, directly-extractable part shows the OM to be thermally immature. The solvent-soluble fractions obtained after acid and alkaline treatments are mostly polar in nature and have a high degree of aliphaticity. C(1s) NEXAFS analysis of water soluble organic fractions indicates a progressive increase in aliphaticity and a decrease in carboxylic/carbonyl groups with consecutive extraction steps.

  6. Evaluating CO2 mineralization capacity of sedimentary rock Using BCR sequential extraction procedures

    Science.gov (United States)

    Yang, Gang-Ting; Yu, Chi-Wen; Yang, Hsiao-Ming; Chiao, Chung-Hui; Yang, Ming-Wei

    2015-04-01

    To relief the high concentration of carbon dioxide in the atmosphere, carbon capture and storage (CCS) is gradually becoming an important concept to reduce greenhouse gas emissions. In IPCC Special Report on CCS, the storage mechanisms for geological formations are categorized into structural/stratigraphic, hydrodynamic and geochemical trappings. Geochemical trapping is considered as a storage mechanism, which can further increase storage capacity, effectiveness and security in terms of permanent CO2 sequestration. The injected CO2 can have geochemical interactions with pore fluid and reservoir rocks and transform into minerals. It is important to evaluate the capacity of reservoir rock for sequestrating CO2. In this study, sedimentary rock samples were collected from a 2-km-deep well in Midwestern Taiwan; and, the BCR sequential extraction experiments developed by European Union Measurement and Testing Programme were conducted. BCR was designed for extracting three major phases from soil, including exchangeable phase and carbonates (the first stage), reducible phase (the second stage) and oxidizable phase (the third stage). The chemistry of extracted solutions and rock residues were measured with ICP-MS and XRF, respectively. According to the results of XRF, considerable amounts of calcium and iron can be extracted by BCR procedures but other cations are negligible. In general, shale has a higher capacity of CO2 sequestration than sandstone. The first stage of extraction can release about 6 (sandstone) to 18.5 (shale) g of calcium from 1 kg rock, which are equivalent to 6.6 and 20.4 g CO2/kg rock, respectively. In the second stage extraction, 0.71 (sandstone) to 1.38 (shale) g/kg rock of iron can be released and can mineralized 0.56 to 1.08 g CO2/kg rock. However, there are no considerable cations extracted in the third stage of BCR as shown by the XRF analysis. In addition, the results of ICP-MS show that Mg can be released in the order of 10-3 g from 1 kg rock

  7. Competitive Complexation of Copper and Zinc by Sequentially Extracted Humic Substances from Manure Compost

    Institute of Scientific and Technical Information of China (English)

    LIU Shuai; WANG Xu-dong; LU Li-lan; DIAO Shi-rong; ZHANG Jun-feng

    2008-01-01

    Chicken manure with similar content of copper and zinc was chosen to conduct a composting experiment to investigate the changes of organic carbon and humus substance complexed copper (HS-Cu) and zinc (HS-Zn), which were extracted by water (H2O), sodium hydroxide (NaOH), and sodium pyrophate-NaOH mixture (Na4P2O7-NaOH), sequentially. Distributions of copper and zinc in fulvic acids (FA) and humic acids (HA) in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg-' in the raw material to 1100 mg kg-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process.

  8. Triblock and pentablock terpolymers by sequential base-assisted living cationic copolymerization of functionalized vinyl ethers

    KAUST Repository

    Bouchekif, Hassen

    2015-01-01

    A series of novel, well-defined triblock (PnBVE-b-PCEVE-b-PSiDEGVE) and pentablock (PSiDEGVE-b-PCEVE-b-PnBVE-b-PCEVE-b-PSiDEGVE) terpolymers of n-butyl vinyl ether (nBVE), 2-chloroethyl vinyl ether (CEVE) and tert-butyldimethylsilyl ethylene glycol vinyl ether (SiEGVE) were synthesized by sequential base-assisted living cationic polymerization. The living character of the homopolymerization of the three VE monomers and the crossover reaction resulting in the formation of well-defined block copolymers were investigated in various solvents (toluene, dichloromethane and n-hexane) using either a monofunctional [nBVE-acetic acid adduct (nBEA), CEVE-acetic acid adduct (CEEA) and SiDEGVE-acetic acid adduct (SiDEGEA)] or a difunctional [1,4-cyclohexane-1,4-diyl bis(2-methoxyethyl acetate) (cHDMEA)] initiator. All initiators are structurally equivalent to the dormant species of the corresponding monomers in order to achieve fast initiation. The optimal conditions of polymerization were achieved in n-hexane at -20 °C, in the presence of 1 M AcOEt (base). Good control over the number average molecular weight (Mn) and the polydispersity index (PDI) was obtained only at [Et3Al2Cl3]0 = [Chain-end]0 ≤ 10 mM. 2,6-Di-tert-butylpyridine (DtBP) was used as a non-nucleophilic proton trap to suppress any protonic initiation from moisture (i.e., Et3Al2Cl3·H2O). Well-defined PnBVEn-b-PCEVEp-b-PSiDEGVEq and PSiDEGVEq-b-PCEVEp-b-PnBVEn-b-PCEVEp-b-PSiDEGVEq terpolymers with a high crossover efficiency, no PCEVE-induced physical gelation, and predictable Mn and PDI < 1.15 were synthesized successfully provided that the targeted DPCEVE/DPnBVE ratio (i.e., p/n) did not exceed 2 and 0.2, respectively. The quantitative desilylation of the PSiEGVE by n-Bu4N+F- in THF at 0 °C led to triblock and pentablock terpolymers in which the PCEVE is the central block and the polyalcohol is the outer block. The thermal properties of the synthesized materials were examined by differential scanning

  9. Fractionation study in bioleached metallurgy wastes using six-step sequential extraction.

    Science.gov (United States)

    Krasnodebska-Ostrega, Beata; Pałdyna, Joanna; Kowalska, Joanna; Jedynak, Łukasz; Golimowski, Jerzy

    2009-08-15

    The stored metallurgy wastes contain residues from ore processing operations that are characterized by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria. In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland (Szklary). Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied. Analyses of the extracts were performed by ICP-MS and FAAS. To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. 80-100% of total metal concentrations were mobilized after the proposed treatment. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.

  10. Evaluating bioavailability of organic pollutants in soils by sequential ultrasonic extraction procedure.

    Science.gov (United States)

    Wu, Xiang; Zhu, Lizhong

    2016-08-01

    Under current retrospective risk assessment framework, the total concentrations of organic pollutants in soils have been employed as the standard for over 30 years. The total concentrations reflect the overall accumulation in soils but tend to be overly conservative for assessing the ecological risks, where the bioavailability plays an important role. In this study, the bioavailability of organic pollutants in soils was evaluated using a stepwise and tiered classification method, namely the sequential ultrasonic extraction procedure (SEUP). The water-soluble and acid-soluble fractions extracted by the SEUP were the bioavailable fractions. The reliability and environmental relevance of the speciation method were examined with representative organic pollutants using the root uptake methods and the semipermeable membrane devices (SPMDs). The plant uptake amounts corrected with weight were highly correlated with the bioavailable fractions (R(2) > 0.75). The amounts of the bioavailable fractions were negatively correlated with the logKow values (R(2) ranging from 0.71 to 0.77) of the organic pollutants and the contents of soil organic matter (R(2) ranging from 0.68 to 0.96). As a refinement of the current risk assessment framework, the SUEP that has proved to be a reliable and convenient is thus highly recommended for evaluating the bioavailability of organic pollutants in soils. PMID:27156212

  11. Application of sequential extraction analysis to electrokinetic remediation of cadmium, nickel and zinc from contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Giannis, Apostolos, E-mail: apostolos.giannis@enveng.tuc.gr [Department of Environmental Engineering, Technical University of Crete, Politechnioupolis, Chania 73100 (Greece); Pentari, Despina [Department of Mineral Resources Engineering, Technical University of Crete, Politechnioupolis, Chania 73100 (Greece); Wang, Jing-Yuan [Residues and Resource Reclamation Centre (R3C), Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Gidarakos, Evangelos, E-mail: gidarako@mred.tuc.gr [Department of Environmental Engineering, Technical University of Crete, Politechnioupolis, Chania 73100 (Greece)

    2010-12-15

    An enhanced electrokinetic process for the removal of cadmium (Cd), nickel (Ni) and zinc (Zn) from contaminated soils was performed. The efficiency of the chelate agents nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA) and diaminocycloexanetetraacetic acid (DCyTA) was examined under constant potential gradient (1.23 V/cm). The results showed that chelates were effective in desorbing metals at a high pH, with metal-chelate anion complexes migrating towards the anode. At low pH, metals existing as dissolved cations migrated towards the cathode. In such conflicting directions, the metals accumulated in the middle of the cell. Speciation of the metals during the electrokinetic experiments was performed to provide an understanding of the distribution of the Cd, Ni and Zn. The results of sequential extraction analysis revealed that the forms of the metals could be altered from one fraction to another due to the variation of physico-chemical conditions throughout the cell, such as pH, redox potential and the chemistry of the electrolyte solution during the electrokinetic treatment. It was found that binding forms of metals were changed from the difficult type to easier extraction type.

  12. Application of sequential extraction analysis to electrokinetic remediation of cadmium, nickel and zinc from contaminated soils.

    Science.gov (United States)

    Giannis, Apostolos; Pentari, Despina; Wang, Jing-Yuan; Gidarakos, Evangelos

    2010-12-15

    An enhanced electrokinetic process for the removal of cadmium (Cd), nickel (Ni) and zinc (Zn) from contaminated soils was performed. The efficiency of the chelate agents nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA) and diaminocycloexanetetraacetic acid (DCyTA) was examined under constant potential gradient (1.23 V/cm). The results showed that chelates were effective in desorbing metals at a high pH, with metal-chelate anion complexes migrating towards the anode. At low pH, metals existing as dissolved cations migrated towards the cathode. In such conflicting directions, the metals accumulated in the middle of the cell. Speciation of the metals during the electrokinetic experiments was performed to provide an understanding of the distribution of the Cd, Ni and Zn. The results of sequential extraction analysis revealed that the forms of the metals could be altered from one fraction to another due to the variation of physico-chemical conditions throughout the cell, such as pH, redox potential and the chemistry of the electrolyte solution during the electrokinetic treatment. It was found that binding forms of metals were changed from the difficult type to easier extraction type. PMID:20833468

  13. Application of sequential extraction analysis to electrokinetic remediation of cadmium, nickel and zinc from contaminated soils

    International Nuclear Information System (INIS)

    An enhanced electrokinetic process for the removal of cadmium (Cd), nickel (Ni) and zinc (Zn) from contaminated soils was performed. The efficiency of the chelate agents nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA) and diaminocycloexanetetraacetic acid (DCyTA) was examined under constant potential gradient (1.23 V/cm). The results showed that chelates were effective in desorbing metals at a high pH, with metal-chelate anion complexes migrating towards the anode. At low pH, metals existing as dissolved cations migrated towards the cathode. In such conflicting directions, the metals accumulated in the middle of the cell. Speciation of the metals during the electrokinetic experiments was performed to provide an understanding of the distribution of the Cd, Ni and Zn. The results of sequential extraction analysis revealed that the forms of the metals could be altered from one fraction to another due to the variation of physico-chemical conditions throughout the cell, such as pH, redox potential and the chemistry of the electrolyte solution during the electrokinetic treatment. It was found that binding forms of metals were changed from the difficult type to easier extraction type.

  14. Microwave Assisted Extraction of Phenolic Compounds from Four Different Spices

    Directory of Open Access Journals (Sweden)

    Alberto Ritieni

    2010-09-01

    Full Text Available Spices and herbs are known not only for their taste, aroma and flavour, but also for their medical properties and value. Both spices and herbs have been used for centuries in traditional medical systems to cure various kinds of illnesses such as common cold, diabetes, cough and cancers. The aim of this work was the comparison between two different extractive techniques in order to get qualitative and quantitative data regarding bioactive compounds of four different spices (Cinnamomum zeylanicum, Coriandrum sativum, Cuminum cyminum, Crocus sativus. The plants were extracted employing ultrasonication and microwave-assisted extractions. The efficiency of extraction of bioactive compounds obtained with the microwave extraction process was in general about four times higher than that resulting from sonication extraction. The various extracts obtained were analyzed for their antioxidant activity using ABTS, DPPH and FRAP assays and for their total polyphenolic content. It can be concluded that microwave-assisted extractions provide significant advantages in terms of extraction efficiency and time savings.

  15. ASSESSMENT OF A SEQUENTIAL EXTRACTION PROCEDURE FOR PERTURBED LEAD-CONTAMINATED SAMPLES WITH AND WITHOUT PHOSPHOROUS AMENDMENTS

    Science.gov (United States)

    Sequential extraction procedures are used to determine the solid-phase association in which elements of interest exist in soil and sediment matrices. Foundational work by Tessier et al. (1) has found widespread acceptance and has worked tolerably as an operational definition for...

  16. Vapor Extraction/Bioventing Sequential Treatment of Soil Contaminated with Volatile and SemiVolatile Hydrocarbon Mixtures

    NARCIS (Netherlands)

    Malina, G.; Grotenhuis, J.T.C.; Rulkens, W.H.

    2002-01-01

    A cost-effective removal strategy was studied in bench-scale columns that involved vapor extraction and bioventing sequential treatment of toluene- and decane-contaminated soil. The effect of operating mode on treatment performance was examined at a continuous air flow and consecutively at two diffe

  17. Extraction of Dihydroquercetin from Larix gmelinii with Ultrasound-Assisted and Microwave-Assisted Alternant Digestion

    OpenAIRE

    Yuangang Zu; Chunjian Zhao; Fengjian Yang; Lei Yang; Wenjie Wang; Chunhui Ma

    2012-01-01

    An ultrasound and microwave assisted alternant extraction method (UMAE) was applied for extracting dihydroquercetin (DHQ) from Larix gmelinii wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory...

  18. Study on microwave assisted process in chemical extraction

    International Nuclear Information System (INIS)

    The microwave assisted process is a revolutionary method of extraction that reduces the extraction time to as little as a few seconds, with up to a ten-fold decrease in the use of solvents. The target material is immersed in solvent that is transparent to microwaves, so only the target material is heated, and because of the microwaves tend to heat the inside of the material quickly, the target chemical are expelled in a few seconds. benefits from this process include significant reductions in the amount of energy required and substantial reductions in the cost and dispose of hazardous solvents. A thorough review has been displayed on: using the microwave in extraction, applications of microwave in industry, process flow diagram, mechanism of the process and comparison between microwave process and other extraction techniques (soxhlet, steam distillation and supercritical fluid). This review attempts to summarize the studies about microwave assisted process as a very promising technique. (Author)

  19. Ultrasound-assisted extraction of total flavonoids from Inula helenium

    OpenAIRE

    Jin Wang; Yong-Ming Zhao; Chun-Yan Guo; Shao-Meng Zhang; Chun-Lei Liu; Dan-Shen Zhang; Xue-Mei Bai

    2012-01-01

    Background: Inula helenium was a perennial herb belonging to composite family and the roots of I. helenium have been widely used in traditional Chinese medicine. In this study, I. helenium was used as an experimental matrix. Materials and Methods: Ultrasound-assisted extraction (UAE) of total flavonoids from I. helenium was studied with dual wavelength UV-VIS spectrophotometer. Effects of various factors including ratio of material to liquid, ultrasonic time, ethanol concentration and extract...

  20. Extraction of cocoa proanthocyanidins and their fractionation by sequential centrifugal partition chromatography and gel permeation chromatography.

    Science.gov (United States)

    Pedan, Vasilisa; Fischer, Norbert; Rohn, Sascha

    2016-08-01

    Cocoa beans contain secondary metabolites ranging from simple alkaloids to complex polyphenols with most of them believed to possess significant health benefits. The increasing interest in these health effects has prompted the need to develop techniques for their extraction, fractionation, separation, and analysis. This work provides an update on analytical procedures with a focus on establishing a gentle extraction technique. Cocoa beans were finely ground to an average particle size of <100 μm, defatted at 20 °C using n-hexane, and extracted three times with 50 % aqueous acetone at 50 °C. Determination of the total phenolic content was done using the Folin-Ciocalteu assay, the concentration of individual polyphenols was analyzed by electrospray ionization high performance liquid chromatography-mass spectrometry (ESI-HPLC/MS). Fractions of bioactive compounds were separated by combining sequential centrifugal partition chromatography (SCPC) and gel permeation column chromatography using Sephadex LH-20. For SCPC, a two-phase solvent system consisting of ethyl acetate/n-butanol/water (4:1:5, v/v/v) was successfully applied for the separation of theobromine, caffeine, and representatives of the two main phenolic compound classes flavan-3-ols and flavonols. Gel permeation chromatography on Sephadex LH-20 using a stepwise elution sequence with aqueous acetone has been shown for effectively separating individual flavan-3-ols. Separation was obtained for (-)-epicatechin, proanthocyanidin dimer B2, trimer C1, and tetramer cinnamtannin A2. The purity of alkaloids and phenolic compounds was determined by HPLC analysis and their chemical identity was confirmed by mass spectrometry. PMID:27318471

  1. Iron Cycling in Marine Sediments - New Insights from Isotope Analysis on Sequentially Extracted Fe Fractions

    Science.gov (United States)

    Henkel, S.; Kasten, S.; Poulton, S.; Hartmann, J.; Staubwasser, M.

    2014-12-01

    Reactive Fe (oxyhydr)oxides preferentially undergo early diagenetic cycling and may cause a diffusive flux of dissolved Fe2+ from sediments towards the sediment-water interface. The partitioning of Fe in sediments has traditionally been studied by applying sequential extractions based on reductive dissolution of Fe minerals. We complemented the sequential leaching method by Poulton and Canfield [1] in order to be able to gain δ56Fe data for specific Fe fractions, as such data are potentially useful to study Fe cycling in marine environments. The specific mineral fractions are Fe-carbonates, ferrihydrite + lepidocrocite, goethite + hematite, and magnetite. Leaching was performed with acetic acid, hydroxylamine-HCl, Na-dithionite and oxalic acid. The processing of leachates for δ56Fe analysis involved boiling the samples in HCl/HNO3/H2O2, Fe precipitation and anion exchange column chromatography. The new method was applied to short sediment cores from the North Sea and a bay of King George Island (South Shetland Islands, Antarctica). Downcore mineral-specific variations in δ56Fe revealed differing contributions of Fe (oxyhydr)oxides to redox cycling. A slight decrease in easily reducible Fe oxides correlating with a slight increase in δ56Fe for this fraction with depth, which is in line with progessive dissimilatory iron reduction [2,3], is visible in the top 10 cm of the North Sea core, but not in the antarctic sediments. Less reactive (dithionite and oxalate leachable) fractions did not reveal isotopic trends. The acetic acid-soluble fraction displayed pronounced δ56Fe trends at both sites that cannot be explained by acid volatile sulfides that are also extracted by acetic acid [1]. We suggest that low δ56Fe values in this fraction relative to the pool of easily reducible Fe oxides result from adsorbed Fe(II) that was open to isotopic exchange with oxide surfaces, affirming the experimental results of Crosby el al. [2]. Hence, δ56Fe analyses on marine

  2. Enzyme assisted protein extraction from rapeseed, soybean, and microalgae meals

    NARCIS (Netherlands)

    Sari, Y.W.; Bruins, M.E.; Sanders, J.P.M.

    2013-01-01

    Oilseed meals that are by-products from oil production are potential resources for protein. The aim of this work is to investigate the use of enzymes in assisting in the extraction of protein from different oilseed meals, namely rapeseed, soybean, and microalgae meals. In addition, microalgae withou

  3. Microwave-Assisted Extraction of Phenolic Antioxidants from Potato Peels

    OpenAIRE

    Valérie Orsat; Raghavan, G. S. V.; Donnelly, Danielle J.; Yvan Gariepy; Kebba Sabally; Stan Kubow; Ashutosh Singh

    2011-01-01

    A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t) (min), solvent (methanol) concentration (S) (v/v) and microwave power level (MP) for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g−1 dry weight (dw) was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g−1 dw), caffeic acid (1.33 mg g−1 dw), ferulic acid (0.50 mg g−1 dw) max contents were obtained a...

  4. Sequential extraction applied to Peruibe black mud, SP, Brazil; Extracao sequencial aplicada a lama negra de Peruibe

    Energy Technology Data Exchange (ETDEWEB)

    Torrecilha, Jefferson Koyaishi

    2014-07-01

    The Peruibe Black mud is used in therapeutic treatments such as psoriasis, peripheral dermatitis, acne and seborrhoea, as well as in the treatment of myalgia, arthritis, rheumatism and non-articular processes. Likewise other medicinal clays, it may not be free from possible adverse health effects due to possible hazardous minerals leading to respiratory system occurrences and other effects, caused by the presence of toxic elements. Once used for therapeutic purposes, any given material should be fully characterized and thus samples of Peruibe black mud were analyzed to determine physical and chemical properties: moisture content, organic matter and loss on ignition; pH, particle size, cation exchange capacity and swelling index. The elemental composition was determined by Neutron Activation Analysis, Atomic Absorption Graphite Furnace and X-ray fluorescence; the mineralogical composition was determined by X-ray diffraction. Another tool widely used to evaluate the behavior of trace elements, in various environmental matrices, is the sequential extraction. Thus, a sequential extraction procedure was applied to fractionate the mud in specific geochemical forms and verify how and how much of the elements may be contained in it. Considering the several sequential extraction procedures, BCR-701 method (Community Bureau of Reference) was used since it is considered the most reproducible among them. A simple extraction with an artificial sweat was, also, applied in order to verify which components are potentially available for absorption by the patient skin during the topical treatment. The results indicated that the mud is basically composed by a silty-clay material, rich in organic matter and with good cation exchange capacity. There were no significant variations in mineralogy and elemental composition of both, in natura and mature mud forms. The analysis by sequential extraction and by simple extraction indicated that the elements possibly available in larger

  5. Optimization of enzyme assisted extraction of polysaccharides from Astragalus membranaceus.

    Science.gov (United States)

    Chen, Huaguo; Zhou, Xin; Zhang, Junzeng

    2014-10-13

    Astragalus polysaccharide (APS) is known to have a variety of pharmacological activities. In the present study, enzyme assisted extraction of APS from Astragalus mongholicus using various enzymes were examined. Research found that glucose oxidase offered a better performance in enhancement of extraction yields of APS than other ones. Glucose oxidase assisted extraction process was further optimized by using response surface method (RSM) to obtain maximum yield of crude APS. The optimized extraction conditions were as follows: enzyme amount of 3.0%, enzyme treated time of 3.44 d, enzyme treated temperature of 56.9 °C and extraction solvent pH of 7.8. Under these conditions, the experimental yield was 29.96 ± 0.14%, which was well in close agreement with the value (30.19%) predicted by RSM model and increased more than 250% compared with none enzyme treated ones. Pharmacological test showed that enzyme assisted APS had a better antioxidant activity (about 2 times higher) than none enzyme treated ones.

  6. Study of Cu and Pb partitioning in mine tailings using the Tessier sequential extraction scheme

    Science.gov (United States)

    Andrei, Mariana Lucia; Senila, Marin; Hoaghia, Maria Alexandra; Borodi, Gheorghe; Levei, Erika-Andrea

    2015-12-01

    The Cu and Pb partitioning in nonferrous mine tailings was investigated using the Tessier sequential extraction scheme. The contents of Cu and Pb found in the five operationally defined fractions were determined by inductively coupled plasma optical emission spectrometry. The results showed different partitioning patterns for Cu and Pb in the studied tailings. The total Cu and Pb contents were higher in tailings from Brazesti than in those from Saliste, while the Cu contents in the first two fractions considered as mobile were comparable and the content of mobile Pb was the highest in Brazesti tailings. In the tailings from Saliste about 30% of Cu and 3% of Pb were found in exchangeable fraction, while in those from Brazesti no metals were found in the exchangeable fraction, but the percent of Cu and Pb found in the bound to carbonate fraction were high (20% and 26%, respectively). The highest Pb content was found in the residual fraction in Saliste tailings and in bound to Fe and Mn oxides fraction in Brazesti tailings, while the highest Cu content was found in the fraction bound to organic matter in Saliste tailings and in the residual fraction in Brazesti tailings. In case of tailings of Brazesti medium environmental risk was found both for Pb and Cu, while in case of Saliste tailings low risk for Pb and high risk for Cu were found.

  7. Speciation of metals in uranium mill tailings using sequential extraction technique

    International Nuclear Information System (INIS)

    Mining sites contain residues from ore processing operations that are characterised by high concentrations of heavy metals. The form in which a metal exists strongly influences its mobility and thus, effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. Investigation of the existing chemical forms and the concentrations of Mn, Pb, Cu, Fe, Zn and natural U in uranium mill tailings samples from Judged were carried out. The concentrations of Nat. U was found to vary from 81.05 to 120.21 μg g-1, and most common mode of occurrence of Nat. U in the tailings is in association with exchangeable species, Fe-Mn oxides and residual form. The dominant chemical form of Nat. U in TP-2 was exchangeable species. The concentration of Mn, Pb, Cu and Zn ranged from 326.5-1395.9, 28.6-41.4, 214.97-508 and 16.49-20.93 μg g-1, respectively. (author)

  8. Arsenic release from arsenopyrite weathering: Insights from sequential extraction and microscopic studies

    International Nuclear Information System (INIS)

    Highlights: ► We studied arsenopyrite weathering reactions in rocks and sediments at mine site. ► Arsenopyrite oxidizes to scorodite, which dissolves incongruently to Fe hydroxide. ► Weathering of arsenopyrite to Fe hydroxide releases As to water. ► Dominant As reservoir in sediment is Fe hydroxide. -- Abstract: At a former As mine site, arsenopyrite oxidation has resulted in formation of scorodite and As-bearing iron hydroxide, both in host rock and mine tailings. Electron microprobe analysis documents that arsenopyrite weathers along two pathways: one that involves formation of sulfur, and one that does not. In both pathways, arsenopyrite oxidizes to form scorodite, which dissolves incongruently to form As-bearing iron hydroxides. From a mass balance perspective, arsenopyrite oxidation to scorodite conserves As, but as scorodite dissolves incongruently to iron hydroxides, As is released to solution, resulting in elevated As concentrations in the headwater stream adjacent to the site. The As-bearing iron hydroxide is the dominant solid phase reservoir of As in mine tailings and stream sediment, as suggested by sequential extraction. This As-bearing iron hydroxide is stable under the aerobic and pH 4–6 conditions at the site; however, changes in biogeochemical conditions resulting from sediment burial or future remedial efforts, which could promote As release from this reservoir due to reductive dissolution, should be avoided

  9. Arsenic release from arsenopyrite weathering: insights from sequential extraction and microscopic studies.

    Science.gov (United States)

    Basu, Ankan; Schreiber, Madeline E

    2013-11-15

    At a former As mine site, arsenopyrite oxidation has resulted in formation of scorodite and As-bearing iron hydroxide, both in host rock and mine tailings. Electron microprobe analysis documents that arsenopyrite weathers along two pathways: one that involves formation of sulfur, and one that does not. In both pathways, arsenopyrite oxidizes to form scorodite, which dissolves incongruently to form As-bearing iron hydroxides. From a mass balance perspective, arsenopyrite oxidation to scorodite conserves As, but as scorodite dissolves incongruently to iron hydroxides, As is released to solution, resulting in elevated As concentrations in the headwater stream adjacent to the site. The As-bearing iron hydroxide is the dominant solid phase reservoir of As in mine tailings and stream sediment, as suggested by sequential extraction. This As-bearing iron hydroxide is stable under the aerobic and pH 4-6 conditions at the site; however, changes in biogeochemical conditions resulting from sediment burial or future remedial efforts, which could promote As release from this reservoir due to reductive dissolution, should be avoided.

  10. Study of Cu and Pb partitioning in mine tailings using the Tessier sequential extraction scheme

    Energy Technology Data Exchange (ETDEWEB)

    Andrei, Mariana Lucia, E-mail: marianaluciaandrei@yahoo.com [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath, 400293 Cluj-Napoca (Romania); Babes-Bolyai University, Environmental Science and Engineering Faculty, 30 Fantanele, 400294, Cluj-Napoca (Romania); Senila, Marin; Hoaghia, Maria Alexandra; Levei, Erika-Andrea [INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath, 400293, Cluj-Napoca (Romania); Borodi, Gheorghe [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath, 400293 Cluj-Napoca (Romania)

    2015-12-23

    The Cu and Pb partitioning in nonferrous mine tailings was investigated using the Tessier sequential extraction scheme. The contents of Cu and Pb found in the five operationally defined fractions were determined by inductively coupled plasma optical emission spectrometry. The results showed different partitioning patterns for Cu and Pb in the studied tailings. The total Cu and Pb contents were higher in tailings from Brazesti than in those from Saliste, while the Cu contents in the first two fractions considered as mobile were comparable and the content of mobile Pb was the highest in Brazesti tailings. In the tailings from Saliste about 30% of Cu and 3% of Pb were found in exchangeable fraction, while in those from Brazesti no metals were found in the exchangeable fraction, but the percent of Cu and Pb found in the bound to carbonate fraction were high (20% and 26%, respectively). The highest Pb content was found in the residual fraction in Saliste tailings and in bound to Fe and Mn oxides fraction in Brazesti tailings, while the highest Cu content was found in the fraction bound to organic matter in Saliste tailings and in the residual fraction in Brazesti tailings. In case of tailings of Brazesti medium environmental risk was found both for Pb and Cu, while in case of Saliste tailings low risk for Pb and high risk for Cu were found.

  11. Study of Cu and Pb partitioning in mine tailings using the Tessier sequential extraction scheme

    International Nuclear Information System (INIS)

    The Cu and Pb partitioning in nonferrous mine tailings was investigated using the Tessier sequential extraction scheme. The contents of Cu and Pb found in the five operationally defined fractions were determined by inductively coupled plasma optical emission spectrometry. The results showed different partitioning patterns for Cu and Pb in the studied tailings. The total Cu and Pb contents were higher in tailings from Brazesti than in those from Saliste, while the Cu contents in the first two fractions considered as mobile were comparable and the content of mobile Pb was the highest in Brazesti tailings. In the tailings from Saliste about 30% of Cu and 3% of Pb were found in exchangeable fraction, while in those from Brazesti no metals were found in the exchangeable fraction, but the percent of Cu and Pb found in the bound to carbonate fraction were high (20% and 26%, respectively). The highest Pb content was found in the residual fraction in Saliste tailings and in bound to Fe and Mn oxides fraction in Brazesti tailings, while the highest Cu content was found in the fraction bound to organic matter in Saliste tailings and in the residual fraction in Brazesti tailings. In case of tailings of Brazesti medium environmental risk was found both for Pb and Cu, while in case of Saliste tailings low risk for Pb and high risk for Cu were found

  12. Site energy distribution analysis of Cu (Ⅱ) adsorption on sediments and residues by sequential extraction method.

    Science.gov (United States)

    Jin, Qiang; Yang, Yan; Dong, Xianbin; Fang, Jimin

    2016-01-01

    Many models (e.g., Langmuir model, Freundlich model and surface complexation model) have been successfully used to explain the mechanism of metal ion adsorption on the pure mineral materials. These materials usually have a homogeneous surface where all sites have the same adsorption energies. However, it's hardly appropriate for such models to describe the adsorption on heterogeneous surfaces (e.g., sediment surface), site energy distribution analysis can be to. In the present study, the site energy distribution analysis was used to describe the surface properties and adsorption behavior of the non-residual and residual components extracted from the natural aquatic sediment samples. The residues were prepared "in-situ" by using the sequential extraction procedure. The present study is intended to investigate the roles of different components and the change of site energy distribution at different temperatures of the sediment samples in controlling Cu (Ⅱ) adsorption. The results of the site energy distribution analysis indicated firstly, that the sorption sites of iron/manganese hydrous oxides (IMHO) and organic matter (OM) have higher energy. Secondly, light fraction (LF) and carbonates have little influence on site energy distribution. Finally, there was increase in site energies with the increase of temperature. Specially, low temperature (5 °C) significantly influenced the site energies of IMHO and OM, and also had obvious effect on the energy distribution of the sediments after removing target components. The site energy distribution analysis proved to be a useful method for us to further understand the energetic characteristics of sediment in comparison with those previously obtained. PMID:26552542

  13. Behaviour of radiocesium in a turf weakly podzolic loam soil: critical evaluation of the sequential extraction results

    International Nuclear Information System (INIS)

    A sequential extraction procedure was applied to study the behavior of radiocesium in a turf weakly podzolic soil. The soil was sampled within the 30-km zone of the Chernobyl NPP (near Buryakivka village). No significant difference between exchangeable fractions for 1990-1995 was observed. However, there was some decreasing in non extractable residues. The redistribution of radiocesium's fraction in the soil during this procedure was studied; decreasing of first fractions was showed. Therefore, it is confirmed that the value of mobile forms of radiocesium obtained by the extraction procedure is underestimated. These results confirm the necessity of improving the methods of cesium's forms definition for soil

  14. Antioxidant Capacity of Rapeseed Extracts Obtained by Conventional and Ultrasound-Assisted Extraction

    OpenAIRE

    Szydłowska-Czerniak, Aleksandra; Tułodziecka, Agnieszka

    2014-01-01

    Ultrasound-assisted extraction (UAE) and conventional solid–liquid extraction were applied to extract total antioxidants from two rapeseed varieties. The antioxidant capacities (AC) of winter and spring rapeseed cultivars were determined by four different analytical methods: ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), 2,2′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The average AC of the studied r...

  15. Fractionation of potentially toxic elements in urban soils from five European cities by means of a harmonised sequential extraction procedure

    International Nuclear Information System (INIS)

    The revised (four-step) BCR sequential extraction procedure has been applied to fractionate the chromium, copper, iron, manganese, nickel, lead and zinc contents in urban soil samples from public-access areas in five European cities. A preliminary inter-laboratory comparison was conducted and showed that data obtained by different laboratories participating in the study were sufficiently harmonious for comparisons to be made between cities and land types (e.g. parks, roadside, riverbanks, etc.). Analyte recoveries by sequential extraction, with respect to direct aqua regia digestion, were generally acceptable (100 ± 15%). Iron, nickel and, at most sites, chromium were found mainly in association with the residual phase of the soil matrix. Copper was present in the reducible, oxidisable and residual fractions, whilst zinc was found in all four sequential extracts. Manganese was strongly associated with reducible material as, in some cities, was lead. This is of concern because high lead concentrations were present in some soils (>500 mg kg-1) and the potential exists for remobilisation under reducing conditions. As would be expected, extractable metal contents were generally highest in older, more heavily industrialised cities. Copper, lead and zinc showed marked (and often correlated) variations in concentrations between sites within the same city whereas manganese and, especially, iron, did not. No overall relationships were, however, found between analyte concentrations and land use, nor between analyte partitioning and land use

  16. Comparison of three-stage sequential extraction and toxicity characteristic leaching tests to evaluate metal mobility in mining wastes

    International Nuclear Information System (INIS)

    Abandoned mining sites contain residues from ore processing operations that are characterised by high concentrations of heavy metals. The form in which a metal exists strongly influences its mobility and, thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. In this work, the modified three-stage sequential extraction procedure proposed by the BCR (now the Standards, Measurements and Testing Programme) was applied for the fractionation of Ni, Zn, Pb and Cd in mining wastes from old Pb-Zn mining areas located in the Val d'Aran (NE Spain) and Cartagena (SE Spain). Analyses of the extracts were performed by inductively coupled plasma atomic emission spectrometry and electrothermal atomic absorption spectrometry. The procedure was evaluated by using a certified reference material, BCR-701. The results of the partitioning study indicate that more easily mobilised forms (acid exchangeable) were predominant for Cd and Zn, particularly in the sample from Cartagena. In contrast, the largest amount of lead was associated with the iron and manganese oxide fractions. On the other hand, the applicability of lixiviation tests commonly used to evaluate the leaching of toxic species from landfill disposal (US-EPA Toxicity Characteristic Leaching Procedure and DIN 38414-S4) to mining wastes was also investigated and the obtained results compared with the information on metal mobility derivable from the application of the three-stage sequential extraction procedure

  17. Parallel versus Sequential Update and the Evolution of Cooperation with the Assistance of Emotional Strategies

    CERN Document Server

    Righi, Simone

    2014-01-01

    Our study contributes to the debate on the evolution of cooperation in the single-shot Prisoner's Dilemma (PD) played on networks. We construct a model in which individuals are connected with positive and negative ties. Some agents play sign-dependent strategies that use the sign of the relation as a shorthand for determining appropriate action toward the opponent. In the context of our model in which network topology, agent strategic types and relational signs coevolve, the presence of sign-dependent strategies catalyzes the evolution of cooperation. We highlight how the success of cooperation depends on a crucial aspect of implementation: whether we apply parallel or sequential strategy update. Parallel updating, with averaging of payoffs across interactions in the social neighborhood, supports cooperation in a much wider set of parameter values than sequential updating. Our results cast doubts about the realism and generalizability of models that claim to explain the evolution of cooperation but implicitly...

  18. Antibacterial activity of sequentially extracted organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis L.from Jaffna

    Institute of Scientific and Technical Information of China (English)

    E; Christy; Jeyaseelan; S; Jenothiny; MK; Pathmanathan; JP; Jeyadevan

    2012-01-01

    Objective:To reveal the antibacterial activity of sequentially extracted different cold organic solvent extracts of fruits,flowers and leaves of Lawsonia inermis(L against)some pathogenic bacteria.Methods:Powders of fruits,flowers and leaves of L inermis were continuously extracted with dichloromethane(DCM),ethyl acetate and ethanol at ambient temperature.The dried extracts were prepared into different concentrations and tested for antibacterial activity by agar well diffusion method,and also the extracts were tested to detennine the available phytochemicals.Results:Except DCM extract of flower all other test extracts revealed inhibitory effect on all tested bacteria and their inhibitory effect differed significantly(P<0.05).The highest inhibitory effect was showed by ethyl acetate extract of flower against Staphylococcus aureus(S.aureus)and Pseudomonas aeruginosa(P.aeruginosa),and ethyl acetate extract of fruit on Escherichia coli(E.coli)and Bacillus subtilis(6.subtilis).The ethyl acetate and ethanol extracts of flower,fruit and leaf expressed inhibition even at 1 mg/100μl against all test bacteria.Among the tested phytochemicals flavonoids were detected in all test extracts except DCM extract of flower.Conclusions:The study demonstrated that the ethyl acetate and ethanol extracts of fruit and flower of L inermis are potentially better source of antibacterial agents compared to leaf extracts of respective solvents.

  19. A new shock wave assisted sandalwood oil extraction technique

    Science.gov (United States)

    Arunkumar, A. N.; Srinivasa, Y. B.; Ravikumar, G.; Shankaranarayana, K. H.; Rao, K. S.; Jagadeesh, G.

    A new shock wave assisted oil extraction technique from sandalwood has been developed in the Shock Waves Lab, IISc, Bangalore. The fragrant oil extracted from sandalwood finds variety of applications in medicine and perfumery industries. In the present method sandal wood specimens (2.5mm diameter and 25mm in length)are subjected to shock wave loading (over pressure 15 bar)in a constant area shock tube, before extracting the sandal oil using non-destructive oil extraction technique. The results from the study indicates that both the rate of extraction as well as the quantity of oil obtained from sandal wood samples exposed to shock waves are higher (15-40 percent) compared to non-destructive oil extraction technique. The compressive squeezing of the interior oil pockets in the sandalwood specimen due to shock wave loading appears to be the main reason for enhancement in the oil extraction rate. This is confirmed by the presence of warty structures in the cross-section and micro-fissures in the radial direction of the wood samples exposed to shock waves in the scanning electron microscopic investigation. In addition the gas chromatographic studies do not show any change in the q uality of sandal oil extracted from samples exposed to shock waves.

  20. Ultrasound assisted extraction and characterization of pectin from tomato waste.

    Science.gov (United States)

    Grassino, Antonela Ninčević; Brnčić, Mladen; Vikić-Topić, Dražen; Roca, Sunčica; Dent, Maja; Brnčić, Suzana Rimac

    2016-05-01

    Pectin was extracted from tomato waste using two different extraction methods to assess its potential utilization as an alternative source of commercial pectin production. Tomato waste was treated with ammonium oxalate/oxalic acid by conventional extraction (CE), under reflux and ultrasound assisted extraction (UAE) at 37 kHz and temperatures of 60 °C and 80 °C. The pectin obtained from these methods was analysed and compared in terms of yield, chemical properties and structure. Among examined methods, CE at 60 °C resulted with the highest yield, but UAE during 15 min of sonication produced the pectin of better quality (anhydrouronic acid, methoxy and calcium pectate contents and degree of esterification). NMR and FTIR spectroscopy of isolated pectins revealed predominantly esterified structure, irrespective of extraction conditions. The comparison of the pectin yields obtained after extraction at 80 °C, indicate that similar values were found at times of 24h and 15 min for CE and UAE, respectively. According to obtained results it can be concluded that main advantage of UAE is considerable shortening of extraction procedure with strong emphasis on environmental friendly processing approach. Therefore, these results suggested that UAE could be used as an efficient technique for the extraction of pectin from tomato waste and by-products.

  1. Computer-Assisted Technique for Surgical Tooth Extraction

    Directory of Open Access Journals (Sweden)

    Hosamuddin Hamza

    2016-01-01

    Full Text Available Introduction. Surgical tooth extraction is a common procedure in dentistry. However, numerous extraction cases show a high level of difficulty in practice. This difficulty is usually related to inadequate visualization, improper instrumentation, or other factors related to the targeted tooth (e.g., ankyloses or presence of bony undercut. Methods. In this work, the author presents a new technique for surgical tooth extraction based on 3D imaging, computer planning, and a new concept of computer-assisted manufacturing. Results. The outcome of this work is a surgical guide made by 3D printing of plastics and CNC of metals (hybrid outcome. In addition, the conventional surgical cutting tools (surgical burs are modified with a number of stoppers adjusted to avoid any excessive drilling that could harm bone or other vital structures. Conclusion. The present outcome could provide a minimally invasive technique to overcome the routine complications facing dental surgeons in surgical extraction procedures.

  2. Sequential Application of Soil Vapor Extraction and Bioremediation Processes for the Remediation of Ethylbenzene-Contaminated Soils

    DEFF Research Database (Denmark)

    Soares, António Carlos Alves; Pinho, Maria Teresa; Albergaria, José Tomás;

    2012-01-01

    Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technol......Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application......: (1) SVE was sufficient to reach the cleanup goals in 63% of the experiments (all the soils with NOMC below 4%), (2) higher NOMCs led to longer SVE remediation times, (3) BR showed to be a possible and cost-effective option when EB concentrations were lower than 335 mg kgsoil −1, and (4...

  3. A sequential extraction procedure to evaluate the mobilization behavior of rare earth elements in soils and tailings materials.

    Science.gov (United States)

    Mittermüller, Marc; Saatz, Jessica; Daus, Birgit

    2016-03-01

    A novel sequential extraction method for evaluation of the mobilization behavior of rare earth elements in soils and mine tailings materials is presented. The sequence consists of the following four steps: 0.05 mol L(-1) calcium nitrate (easily soluble and ion exchange fraction), 0.1 mol L(-1) citric acid (fraction mobilized by complexation and carbonate bound), 0.05 mol L(-1) hydroxylamine hydrochloride (pH = 2) (reducible fraction), 1.4 mol L(-1) nitric acid (acid soluble fraction). The procedure was optimized with a certified soil material and a mine tailings material and was applied to eight samples of a soil profile. The different results obtained by using either the developed method or the widespread used BCR-Method for comparison are discussed. There were clear advantages using the newly created sequential extraction procedure in getting more detailed information about the bioavailable fraction and a fraction addressing REE phosphates. PMID:26766351

  4. A study on the chemical and mineralogical characterization of MSWI fly ash using a sequential extraction procedure

    International Nuclear Information System (INIS)

    The presence of heavy metals in municipal solid waste incineration (MSWI) fly ash is of environmental concern due to their leaching potential in landfill environments. Sequential chemical extraction was performed on fly ash samples from a large-scale municipal solid waste incineration plant in East China. The transformation of the mineralogical species of fly ash during the sequential extraction was studied using X-ray fluorescence (XRF) and X-ray powder diffraction (XRD). The leaching behavior of heavy metals such as zinc, lead, cadmium and copper in MSWI fly ash was considered to have a dependency relationship with the components of calcium, such as aphthitalite, calcite, anhydrite and calcium aluminate or calcium aluminosilicate

  5. Strontium distribution and origins in a natural clayey formation (Callovian-Oxfordian, Paris Basin, France): A new sequential extraction procedure

    OpenAIRE

    Lerouge, Catherine; Gaucher, Eric C.; Tournassat, Christophe; Négrel, Philippe; Crouzet, Catherine; Guerrot, Catherine; Gautier, Anne; Michel, Pascale; Vinsot, Agnès; Buschaert, Stéphane

    2010-01-01

    International audience Strontium is a good monitor of geochemical processes in natural clayey formations. In the Callovian-Oxfordian formation of Bure in France, strontium is sorbed on clay minerals and carried by carbonates, detrital minerals and accessory celestite. In order to determine the strontium distribution among these different phases, four-step sequential extractions (I. cobalt hexamine trichloride, 2. acetic acid, 3. EDTA and 4. tri-acid) were performed on samples from differen...

  6. Sequential extraction and availability of copper in Cu fungicide-amended vineyard soils from Southern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Correa Nogueirol, Roberta [University of Sao Paulo (ESALQ/USP), C.P. 9, Piracicaba 13418-900, SP (Brazil); Ferracciu Alleoni, Luis Reynaldo, E-mail: alleoni@esalq.usp.br [Department of Soil Science, ESALQ/USP. C.P. 9, Piracicaba 13418-900, SP (Brazil); Ribeiro Nachtigall, Gilmar; Wellington de Melo, George [National Research Center of Grapes and Wine - Embrapa Uva e Vinho, C.P. 130, Bento Goncalves 95700-000, RS (Brazil)

    2010-09-15

    The continuous use of cupric fungicides in vineyards, mainly copper sulfate (as a component of the bordeaux mixture), has increased Cu concentration in soils to levels near or even above the maximum established by the Commission of Soil Chemistry and Fertility of the States of Santa Catarina and Rio Grande do Sul, Brazil. Besides the total content, the fractions of the element along the soil profile must be known, because the total content of Cu in the soil is not sufficient to express its environmental impact. The objective of this study was to evaluate the variation of Cu contentes along the soil profile and its speciation and partitioning in 29 soil samples from vineyards in the state of Rio Grande do Sul, Brazil. Samples were collected in areas cropped with vineyards older than 15 years that had been frequently treated with the bordeaux mixture. These samples were from Nitosols, Acrisols, Cambisols and Leptosols and were analysed by sequential extractions and several chemical extractors. Soils had diverse chemical and physical attributes: clay content in the plowed layer (0-0.2 m) ranged from 120 to 610 g kg{sup -1}, pH ranged from 5.3 to 7.3 and organic carbon contents varied from 2.9 to 51 g dm{sup -3}. Among the 29 samples, 16 had the total Cu above the maximum limit allowed by the European Community regulations (140 mg kg{sup -1}). The average amount of Cu bonded to the oxide fraction accounted for 49.5% of the total Cu.

  7. Comparison of single and sequential extraction procedures for the study of rare earth elements remobilisation in different types of soils

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Chebrolu Rama Mohan [Geological Survey of India, Hyderabad 500068 (India); Sahuquillo, Angels [Universitat de Barcelona, Department de Quimica Analitica, Marti i Franques, 1-11, E-08028 Barcelona (Spain); Lopez-Sanchez, Jose Fermin, E-mail: fermin.lopez@ub.edu [Universitat de Barcelona, Department de Quimica Analitica, Marti i Franques, 1-11, E-08028 Barcelona (Spain)

    2010-03-10

    With the continual increase in the utilisation of rare earth elements (REE) for industrial and agricultural purposes, research into the environmental and biogeochemical behaviour of REE had attracted much interest in recent times. This study principally describes the distribution of REE in four different types of soils like lateritic soil (S-1), in situ natural soil (S-2), soil contaminated by mining activity (S-3) and accidentally polluted soil (S-4) utilizing the optimised BCR sequential extraction procedure and partial extractions with various types of single extractants such as unbuffered salt solutions 0.1 M NaNO{sub 3}, 0.01 M CaCl{sub 2}, 1 M NH{sub 4}NO{sub 3}; complexing agents 0.005 M DTPA and 0.05 M EDTA; acid solutions 0.43 M CH{sub 3}COOH and 1 M HCl. Comparison of the sum of the four BCR fractions, which included an aqua regia attack on the residue, with the pseudo-total aqua regia digest values to assess the accuracy of the BCR partioning approach has been undertaken. Partial extraction results with several single extractants have also been reported for all the REE elements including yttrium which have been analysed by the optimised BCR procedure. Results obtained after 24 h extraction with each of the single extractant have also been discussed. The extraction with 1 M HCl during 24 h yielded similar quantities of REE as those released under the combined steps of 1, 2 and 3 of the BCR sequential extraction for all the four different type of soil samples indicating that this reagent can be used successfully to estimate the total extractable contents of REE in various types of soil samples.

  8. Comparison of single and sequential extraction procedures for the study of rare earth elements remobilisation in different types of soils

    International Nuclear Information System (INIS)

    With the continual increase in the utilisation of rare earth elements (REE) for industrial and agricultural purposes, research into the environmental and biogeochemical behaviour of REE had attracted much interest in recent times. This study principally describes the distribution of REE in four different types of soils like lateritic soil (S-1), in situ natural soil (S-2), soil contaminated by mining activity (S-3) and accidentally polluted soil (S-4) utilizing the optimised BCR sequential extraction procedure and partial extractions with various types of single extractants such as unbuffered salt solutions 0.1 M NaNO3, 0.01 M CaCl2, 1 M NH4NO3; complexing agents 0.005 M DTPA and 0.05 M EDTA; acid solutions 0.43 M CH3COOH and 1 M HCl. Comparison of the sum of the four BCR fractions, which included an aqua regia attack on the residue, with the pseudo-total aqua regia digest values to assess the accuracy of the BCR partioning approach has been undertaken. Partial extraction results with several single extractants have also been reported for all the REE elements including yttrium which have been analysed by the optimised BCR procedure. Results obtained after 24 h extraction with each of the single extractant have also been discussed. The extraction with 1 M HCl during 24 h yielded similar quantities of REE as those released under the combined steps of 1, 2 and 3 of the BCR sequential extraction for all the four different type of soil samples indicating that this reagent can be used successfully to estimate the total extractable contents of REE in various types of soil samples.

  9. Development of an automated sequential injection on-line solvent extraction-back extraction procedure as demonstrated for the determination of cadmium with detection by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Wang, Jianhua; Hansen, Elo Harald

    2002-01-01

    An automated sequential injection (SI) on-line solvent extraction-back extraction separation/preconcentration procedure is described. Demonstrated for the assay of cadmium by electrothermal atomic absorption spectrometry (ETAAS), the analyte is initially complexed with ammonium...

  10. Ultrasound-assisted extraction of total flavonoids from Inula helenium

    Directory of Open Access Journals (Sweden)

    Jin Wang

    2012-01-01

    Full Text Available Background: Inula helenium was a perennial herb belonging to composite family and the roots of I. helenium have been widely used in traditional Chinese medicine. In this study, I. helenium was used as an experimental matrix. Materials and Methods: Ultrasound-assisted extraction (UAE of total flavonoids from I. helenium was studied with dual wavelength UV-VIS spectrophotometer. Effects of various factors including ratio of material to liquid, ultrasonic time, ethanol concentration and extraction times on extraction yield of total flavonoids were evaluated. Then, orthogonal design of four factors at three levels was applied for optimization the extraction yields of flavonoids from the root of I. helenium. Result: The optimal extracting process of the total flavonoids from the root of the I. helenium was 1 g plant sample with 20 ml of 60% ethanol, extracting twice and each time for 20 min. Conclusion: Under these optimal conditions, the yield of total flavonoids was (17.36±0.94 mg/g. UAE was more efficient and time saving for the extraction of flavonoids from plant materials.

  11. Membrane assisted liquid-liquid extraction of cerium

    International Nuclear Information System (INIS)

    Membrane assisted liquid-liquid extraction of cerium was investigated, with emphasis placed on the study of the reaction chemistry and the kinetics of non-dispersive solvent extraction and stripping with microporous membranes. A bulk liquid membrane process was developed for the purification of cerium(IV) from sulfate solutions containing other rare earth elements. The cerium process was studied in both a flat sheet contained liquid membrane configuration and with hollow fibre contactors. Di-2-ethylhexyl phosphoric acid (DEHPA) was identified as a suitable extractant for cerium(IV) from sulfuric acid solution, with due consideration of factors such as extraction ability, resistance to degradation, solvent selectivity and potential for sulfate transfer into a strip solution. A detailed study of the extraction of cerium(IV) with DEHPA defined the extraction reaction chemistry. The Ce/DEHPA/sulfate system was also investigated with a flat sheet bulk liquid membrane configuration, using both sulfuric and hydrochloric acid as receiver solutions. These tests identified that hydrophobic membranes provide better mass transfer for extraction and hydrophilic membranes are better for stripping. The presence of an impurity, mono 2-ethylhexyl phosphoric acid (MEHPA), was found to have a dramatic accelerating effect on the rate of the chemical extraction reaction. This was attributed to its higher interfacial activity and population compared to DEHPA, and the fact that MEHPA was also found to be an active carrier for cerium(IV). The mass transfer rate of membrane assisted extraction and stripping of cerium, using hydrophobic and hydrophilic microporous membranes, respectively, was investigated using a modified Lewis-type cell. It was quantitatively demonstrated that the extraction process was mainly controlled by membrane diffusion and the stripping process was controlled by the chemical reaction rate, with membrane diffusion becoming important at low distribution coefficients

  12. Dynamic fractionation of trace metals in soil and sediment samples using rotating coiled column extraction and sequential injection microcolumn extraction: a comparative study.

    Science.gov (United States)

    Rosende, Maria; Savonina, Elena Yu; Fedotov, Petr S; Miró, Manuel; Cerdà, Víctor; Wennrich, Rainer

    2009-09-15

    Dynamic fractionation has been recognized as an appealing alternative to conventional equilibrium-based sequential extraction procedures (SEPs) for partitioning of trace elements (TE) in environmental solid samples. This paper reports the first attempt for harmonization of flow-through dynamic fractionation using two novel methods, the so-called sequential injection microcolumn (SIMC) extraction and rotating coiled column (RCC) extraction. In SIMC extraction, a column packed with the solid sample is clustered in a sequential injection system, while in RCC, the particulate matter is retained under the action of centrifugal forces. In both methods, the leachants are continuously pumped through the solid substrates by the use of either peristaltic or syringe pumps. A five-step SEP was selected for partitioning of Cu, Pb and Zn in water soluble/exchangeable, acid-soluble, easily reducible, easily oxidizable and moderately reducible fractions from 0.2 to 0.5 g samples at an extractant flow rate of 1.0 mL min(-1) prior to leachate analysis by inductively coupled plasma-atomic emission spectrometry. Similarities and discrepancies between both dynamic approaches were ascertained by fractionation of TE in certified reference materials, namely, SRM 2711 Montana Soil and GBW 07311 sediment, and two real soil samples as well. Notwithstanding the different extraction conditions set by both methods, similar trends of metal distribution were in generally found. The most critical parameters for reliable assessment of mobilizable pools of TE in worse-case scenarios are the size-distribution of sample particles, the density of particles, the content of organic matter and the concentration of major elements. For reference materials and a soil rich in organic matter, the extraction in RCC results in slightly higher recoveries of environmentally relevant fractions of TE, whereas SIMC leaching is more effective for calcareous soils. PMID:19615513

  13. A multisyringe flow-through sequential extraction system for on-line monitoring of orthophosphate in soils and sediments

    DEFF Research Database (Denmark)

    Buanuam, Janya; Miró, Manuel; Hansen, Elo Harald;

    2007-01-01

    of extracted organic phosphorus and condensed inorganic phosphates within the time frame of the assay. The potential of the novel system for accommodation of the harmonized protocol from the Standards, Measurement and Testing (SMT) Program of the Commission of the European Communities for inorganic phosphorus......A fully automated flow-through microcolumn fractionation system with on-line post-extraction derivatization is proposed for monitoring of orthophosphate in solid samples of environmental relevance. The system integrates dynamic sequential extraction using 1.0 mol l-1 NH4Cl, 0.1 mol l-1 NaOH and 0...... the solid containing microcolumn and the flow-through detector. The proposed flow assembly, capitalizing on the features of the multicommutation concept, implies several advantages as compared to fractionation analysis in the batch mode in terms of saving of extractants and MB reagents, shortening...

  14. Binary Solvent Extraction System and Extraction Time Effects on Phenolic Antioxidants from Kenaf Seeds (Hibiscus cannabinus L.) Extracted by a Pulsed Ultrasonic-Assisted Extraction

    OpenAIRE

    Yu Hua Wong; Hwee Wen Lau; Chin Ping Tan; Kamariah Long; Kar Lin Nyam

    2014-01-01

    The aim of this study was to determine the best parameter for extracting phenolic-enriched kenaf (Hibiscus cannabinus L.) seeds by a pulsed ultrasonic-assisted extraction. The antioxidant activities of ultrasonic-assisted kenaf seed extracts (KSE) were determined by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay, β -carotene bleaching inhibition assay, and ferric reducing antioxi...

  15. Enzyme-assisted aqueous extraction of lipid from microalgae.

    Science.gov (United States)

    Liang, Kehong; Zhang, Qinghua; Cong, Wei

    2012-11-28

    An improved lipid extraction process has been established for microalgal using enzyme-assisted aqueous extraction processing (EAEP), which mainly involved in sonication and enzyme treatment. As compared to cellulase, neutral protease and alkaline protease, significantly higher lipid recovery was achieved by snailase and trypsin. The highest lipid recovery of 49.82% was obtained by a combined sonication-enzyme treatment at pH 4. The enhancement mechanism of the EAEP was analyzed in terms of the particle size of cream and zeta potential. In addition, microalgal lipid recovery was also affected by lipid class composition and the type of algae. The present study demonstrates a promising alternative to conventional lipid extraction of microalgae and the quantitative information on EAEP of oleaginous alga can provide valuable data for process design at pilot and industrial scale.

  16. Ultrasound-assisted extraction and in situ derivatization.

    Science.gov (United States)

    Delgado-Povedano, M M; Luque de Castro, M D

    2013-06-28

    Ultrasound (US) is a type of energy of growing interest for analytical chemists. The favorable effect of US on mass transfer between two phases in the same or different state has been widely demonstrated as did the number of chemical reactions accelerated/improved under ultrasonic influence. The action of US on both mass transfer and chemical reaction developed in a simultaneous manner results in a synergistic effect as a consequence of the "removal" of the target extracted species by conversion into a product. Both US-assisted solid-liquid extraction and liquid-liquid extraction have been developed with in situ derivatization at the meso- and microscale and the advantages involved in their implementation are discussed in this article. PMID:23639123

  17. Enzyme-assisted extraction of lycopene from tomato processing waste.

    Science.gov (United States)

    Zuorro, Antonio; Fidaleo, Marcello; Lavecchia, Roberto

    2011-12-10

    A central composite design was used to optimize the enzyme-assisted extraction of lycopene from the peel fraction of tomato processing waste. Tomato skins were pretreated by a food-grade enzyme preparation with pectinolytic and cellulolytic activities and then subjected to hexane extraction. The factors investigated included extraction temperature (10-50 °C), pretreatment time (0.5-6.5 h), extraction time (0.5-4.5 h), enzyme solution-to-solid ratio (10-50 dm³/kg) and enzyme load (0-0.2 kg/kg). Overall, an 8- to 18-fold increase in lycopene recovery was observed compared to the untreated plant material. From a response surface analysis of the data, a second-degree polynomial equation was developed which provided the following optimal extraction conditions: T=30 °C, extraction time=3.18 h and enzyme load=0.16 kg/kg. The obtained results strongly support the idea of using cell-wall degrading enzymes as an effective means for recovering lycopene from tomato waste.

  18. Sequential combination of robot-assisted therapy and constraint-induced therapy in stroke rehabilitation: a randomized controlled trial.

    Science.gov (United States)

    Hsieh, Yu-Wei; Lin, Keh-Chung; Horng, Yi-Shiung; Wu, Ching-Yi; Wu, Tai-Chieh; Ku, Fang-Ling

    2014-05-01

    Robot-assisted therapy (RT) and constraint-induced therapy (CIT) both show great promise to improve stroke rehabilitation outcomes. Although the respective treatment efficacy of RT and CIT has been validated, the additive effects of RT combined with CIT remain unknown. This study investigated the treatment effects of RT in sequential combination with a distributed form of CIT (RT + dCIT) compared with RT and conventional rehabilitation (CR). Forty-eight patients with stroke were enrolled and randomized to receive one of the three interventions for 4 weeks. Primary outcomes assessed the changes of motor impairment and motor function on the Fugl-Meyer Assessment (FMA) and Wolf Motor Function Test (WMFT). Secondary outcomes, including the Motor Activity Log (MAL) and accelerometers, examined functional performance during daily activities. The three treatment groups improved significantly on most primary and secondary outcomes over time. The combined RT + dCIT group exhibited significantly greater improvement on the FMA and functional ability subscale of the WMFT than the RT and CR groups. The improvements on the MAL and accelerometers were not significantly different among the three groups. RT in sequential combination with CIT led to additive effects on participants' motor ability and functional ability to perform motor tasks after stroke, which support that combined therapy can be an effective means to intensify outcomes. Further research investigating the potential long-term effects of combination therapy, especially on real-life performance, would be valuable.

  19. Single step purification of lactoperoxidase from whey involving reverse micelles-assisted extraction and its comparison with reverse micellar extraction.

    Science.gov (United States)

    Nandini, K E; Rastogi, Navin K

    2010-01-01

    The extraction of lactoperoxidase (EC 1.11.1.7) from whey was studied using single step reverse micelles-assisted extraction and compared with reverse micellar extraction. The reverse micelles-assisted extraction resulted in extraction of contaminating proteins and recovery of lactoperoxidase in the aqueous phase leading to its purification. Reverse micellar extraction at the optimized condition after forward and backward steps resulted in activity recovery of lactoperoxidase and purification factor of the order of 86.60% and 3.25-fold, respectively. Whereas reverse micelles-assisted extraction resulted in higher activity recovery of lactoperoxidase (127.35%) and purification factor (3.39-fold). The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profiles also evidenced that higher purification was obtained in reverse micelles-assisted extraction as compared of reverse micellar extracted lactoperoxidase.

  20. Elemental characterization of coal ash and its leachates using sequential extraction techniques

    International Nuclear Information System (INIS)

    Over 50 million tons of coal ash are produced annually in North America. Technological improvements in air pollution control have decreased stack emissions but have also increased contaminant concentrations in the ash of coal-fired boiler applications. The leaching of heavy metals and other elements during regulatory tests may cause coal ash to be classified as hazardous waste, complicating land disposal. The hazardous nature of coal ash remains unclear because current toxicity tests fail to effectively characterize the elemental distribution and chemical solubility of trace metals in the landfill environment. Leaching characteristics of ash samples can be investigated with various laboratory extraction procedures in association with multi-elemental analytical techniques (e.g., neutron activation analysis and inductively coupled plasma - atomic emission spectroscopy). Such methods provide more thorough analyses of coal ash leaching dynamics than the regulatory assessments can demonstrate. Regulatory elements including Ag, As, Ba, Cd, Cr, Hg, Pb, and Se were shown to remain in largely insoluble forms while elements such as B and S leached at higher levels. Experimental results may assist operators of coal-fired boiler industries in selecting coal types and disposal options to curtail the leaching of potentially toxic inorganic contaminants. (author) 12 refs.; 4 figs.; 3 tabs

  1. Total and extractable formsof Cu, Zn, Ni, Cr, Pb and Fe in vineyard soil (Valandovo Valley, Macedonia) determined by a sequential extraction procedure

    OpenAIRE

    Karakaseva, Elizabeta; Boev, Blazo; Zajkova-Paneva, Vesna

    2012-01-01

    The total and extractable forms of Cu, Zn, Pb, Ni, Cr, and Fe in vineyard soils from the valley of Valandovo were analyzed in order to understand the existence of metals in soils and their potential availability to the flora and fauna. The content of metals was determined by ICP-EAS analysis, while metal binding was defined with a sequential extraction procedure. The total content of Cu, Zn, Pb, Ni, Fe and Cr, in almost all soil samples, did not exceed the maximum permissible cont...

  2. Oil recovery from petroleum sludge through ultrasonic assisted solvent extraction.

    Science.gov (United States)

    Hu, Guangji; Li, Jianbing; Huang, Shuhui; Li, Yubao

    2016-09-18

    The effect of ultrasonic assisted extraction (UAE) process on oil recovery from refinery oily sludge was examined in this study. Two types of UAE treatment including UAE probe (UAEP) system and UAE bath (UAEB) system were investigated. Their oil recovery efficiencies were compared to that of mechanical shaking extraction (MSE). Three solvents including cyclohexane (CHX), ethyl acetate (EA), and methyl ethyl ketone (MEK) were examined as the extraction solvents. The influence of experimental factors on oil and solvent recovery was investigated using an orthogonal experimental design. Results indicated that solvent type, solvent-to-sludge (S/S) ratio, and treatment duration could have significant effects on oil recovery in UAE treatment. Under the optimum conditions, UAEP treatment can obtain an oil recovery of 68.8% within 20 s, which was higher than that (i.e., 62.0%) by MSE treatment after 60 min' extraction. UAEB treatment can also obtain a promising oil recovery within shorter extraction duration (i.e., 15 min) than MSE. UAE was thus illustrated as an effective and improved approach for oily sludge recycling. PMID:27294566

  3. Optimization and orthogonal design of an ultrasonic-assisted aqueous extraction process for extracting chlorogenic acid from dry tobacco leaves

    Institute of Scientific and Technical Information of China (English)

    Martin Tongai Mazvimba; YU Ying; CUI Zhi-Qin; ZHANG Ying

    2012-01-01

    Processing parameters for heat reflux and ultrasonic-assisted extraction techniques were optimized.Optimal operating conditions,extraction solvents and extraction yields for both methods were established.Although methanol showed high extraction efficiency in heat reflux extraction,residual amounts of methanol caused adulteration of extracts.To circumvent this drawback,a novel ultrasonic-assisted aqueous extraction process was optimized and orthogonally designed to pave the way for replacing the toxic organic solvent,methanol with water.A new approach which utilizes fractional volumes of an extraction solvent was developed to minimize solvent consumption,improve chlorogenic acid solubility in water and enhance its aqueous extraction from dried tobacco leaves.Desired trajectories for the new ultrasonic assisted aqueous extraction process were found.

  4. Enhancement of enzymatic saccharification of corn stover with sequential Fenton pretreatment and dilute NaOH extraction.

    Science.gov (United States)

    He, Yu-Cai; Ding, Yun; Xue, Yu-Feng; Yang, Bin; Liu, Feng; Wang, Cheng; Zhu, Zheng-Zhong; Qing, Qing; Wu, Hao; Zhu, Cheng; Tao, Zhi-Cheng; Zhang, Dan-Ping

    2015-10-01

    In this study, an effective method by the sequential Fenton pretreatment and dilute NaOH extraction (FT-AE) was chosen for pretreating corn stover. Before dilute NaOH (0.75 wt%) extraction at 90 °C for 1h, Fenton reagent (0.95 g/L of FeSO4 and 29.8 g/L of H2O2) was employed to pretreat CS at a solid/liquid ratio of 1/20 (w/w) at 35 °C for 30 min. The changes in the cellulose structural characteristics (porosity, morphology, and crystallinity) of the pretreated solid residue were correlated with the enhancement of enzymatic saccharification. After being enzymatically hydrolyzed for 72 h, the reducing sugars and glucose from the hydrolysis of 60 g/L FT-AE-CS pretreated could be obtained at 40.96 and 23.61 g/L, respectively. Finally, the recovered hydrolyzates containing glucose had no inhibitory effects on the ethanol fermenting microorganism. In conclusion, the sequential Fenton pretreatment and dilute NaOH extraction has high potential application in future.

  5. Investigation of trace elements in agricultural Edirne soils by BCR sequential extraction method and its transfer to wheat plants

    International Nuclear Information System (INIS)

    Complete text of publication follows. In this study, soil samples were collected from Edirne-Turkey and subjected to a sequential procedure in order to evaluate the precision of the procedure and determine metal partitioning and concentrations of elements and to investigate the predictability of trace element on plant uptake. The samples were subjected to a three stage extraction procedure proposed by the Community Bureau of Reference (BCR) (G. Rauret et al., J. Environ. Monit., 1 (1999) 57-61.) .The three phases that were separated out were (1) carbonate, exchangeable, (2) Fe-Mn oxides and (3) organic matter. Metal concentrations were determined by ICP-OES. The wheat samples were prepared to analysis using microwave acid digestion procedure (E.P. Nardi et al., food Chem., 112 (2009) 727-732.). The pseudo-total concentrations of metals were determinated after aqua regia digestion (S. Melaku et al., Anal. Chim. Acta, 543 (2005) 117-123.). The analytical accuracy of the method was determinated by using the Standard Reference Materials ( BCR 142R Light Sandy Soil, NIST 2711 Montana Soil, NIST 2704 Buffalo River Sediment) The sum of the metal contents obtained from the modified BCR sequential extraction procedure and pseudo-total metal contents for soil samples were used to calculate recovery values (a. Tokalioglu et al., Intern. J. Environ. Anal. Chem., 86 (2006) 417-430.). In order to evaluate the bioavailability of metals, the relationships between the wheat-metal and soil-extractable metal concentrations were examined.

  6. Speciation of heavy metals by modified BCR sequential extraction procedure in different depths of sediments from Sungai Buloh, Selangor, Malaysia

    International Nuclear Information System (INIS)

    Highlights: → A BCR sequential extraction procedure was applied for measurement of heavy metals in Sungai Buloh sediments in different depths. → The amounts of CF and percentage of RAC was measured in this study too. → Highest CF was obtained for Cd, Co, Pb and Zn in these samples. → Zn at S3 and Cd at S3-S7 showed a high risk for the sediment samples. There were no elements of very high risk conditions in the selected samples. - Abstract: The sequential extraction procedure proposed by the European Standard, Measurements and Testing (SM and T) program, formerly the Community Bureau of Reference (BCR), was applied for partitioning of heavy metals (HMs) in river sediments collected along the course of Sungai Buloh and the Straits of Malacca in Selangor, Malaysia. Eight elements (V, Pb, Cd, Cr, Co, Ni, Cu and Zn) from seven stations (S1-S7) and at different depths were analyzed using the modified BCR Sequential Extraction Procedure (SEP) in combination with ICP-MS to obtain the metal distribution patterns in this region. The results showed that heavy metal contaminations at S2 and S3 was more severe than at other sampling sites, especially for Zn, Cu, Ni and Pb. Nevertheless, the element concentrations from top to bottom layers decreased predominantly. The samples from the Straits of Malacca (S4-S7) the highest contamination factors obtained were for Co, Zn and Pb while the lowest were found for V and Cr, similar to Sungai Buloh sediments. The sediments showed a low risk for V, Cr, Cu and Pb with RAC values of less than 10%, but medium risk for Co, Zn (except S3), Cd at S1 and S2 and Ni at S1, S3 and S5. Zn at S3 and Cd at S3-S7 showed high risk to our sediment samples. There is not any element of very high risk conditions in the selected samples.

  7. Microwave-Assisted Extraction of Phenolic Antioxidants from Potato Peels

    Directory of Open Access Journals (Sweden)

    Valérie Orsat

    2011-03-01

    Full Text Available A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t (min, solvent (methanol concentration (S (v/v and microwave power level (MP for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g−1 dry weight (dw was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g−1 dw, caffeic acid (1.33 mg g−1 dw, ferulic acid (0.50 mg g−1 dw max contents were obtained at S of 100%, t of 15 min, and MP of 10%, while the max chlorogenic acid content (1.35 mg g−1 dw was obtained at S of 100%, t of 5 min, and MP of 10%. The radical scavenging activity of the extract was evaluated by using the DPPH assay and optimum antioxidant activity was obtained at S of 100%, t of 5 min, and MP of 10%.

  8. Microwave-assisted extraction of phenolic antioxidants from potato peels.

    Science.gov (United States)

    Singh, Ashutosh; Sabally, Kebba; Kubow, Stan; Donnelly, Danielle J; Gariepy, Yvan; Orsat, Valérie; Raghavan, G S V

    2011-01-01

    A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t) (min), solvent (methanol) concentration (S) (v/v) and microwave power level (MP) for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g⁻¹ dry weight (dw) was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g⁻¹ dw), caffeic acid (1.33 mg g⁻¹ dw), ferulic acid (0.50 mg g⁻¹ dw) max contents were obtained at S of 100%, t of 15 min, and MP of 10%, while the max chlorogenic acid content (1.35 mg g⁻¹ dw) was obtained at S of 100%, t of 5 min, and MP of 10%. The radical scavenging activity of the extract was evaluated by using the DPPH assay and optimum antioxidant activity was obtained at S of 100%, t of 5 min, and MP of 10%. PMID:21383659

  9. Determination of heavy metals in paddy soils (Kočani Field, Macedonia) by a sequential extraction procedure

    OpenAIRE

    Rogan, Nastja; Dolenec, Tadej; Serafimovski, Todor; Tasev, Goran; Dolenec, Matej

    2008-01-01

    In this study we examine the distribution of heavy metals (As, Cd, Cu, Pb and Zn) in paddy soil samples from Kočani Field (Macedonia) by ICP-EAS and sequential extraction procedure. Very high concentrations of As (42 mg/kg), Cd (5.6 mg/kg), Cu (99 mg/kg), Pb (892 mg/kg) and Zn (1134 mg/kg) were found in the paddy soil sample from location VII-2 in the western part of Kočani Field, close to the Zletovska River, which drains the untreated effuents of the Pb-Zn mine in Zletovo and is used for th...

  10. Assessment of a sequential phase extraction procedure for uranium-series isotope analysis of soils and sediments

    International Nuclear Information System (INIS)

    The study of uranium-series (U-series) isotopes in soil and sediment materials has been proposed to quantify rates and timescales of soil production and sediment transport. Previous works have studied bulk soil or sediment material, which is a complex assemblage of primary and secondary minerals and organic compounds. However, the approach relies on the fractionation between U-series isotopes in primary minerals since they were liberated from the parent rock via weathering. In addition, secondary minerals and organic compounds have their own isotopic compositions such that the composition of the bulk material may not reflect that of primary minerals. Hence, there is a need for a sample preparation procedure that allows the isolation of primary minerals in soil or fluvial sediment samples. In this study, a sequential extraction procedure to separate primary minerals from soils and sediments was assessed. The procedure was applied to standard rock sample powders (TML-3 and BCR-2) to test whether it introduced any artefactual radioactive disequilibrium. A new step was introduced to remove the clay-sized fraction (234U/238U) and (230Th/238U) activity ratios of the rock standards occurred during the procedure. Aliquots of soil sample were subjected to the sequential extraction process to test how each step modifies the uranium-series activity ratios and mineralogy. Although no secondary minerals were detected in the unleached soil aliquots, the sequential leaching process removed up to 17% of U and Th and modified their activity ratios by up to 3%. The modification of the activity ratios poses a demand for careful means to avoid redistribution of isotopes back to the residual phase during phase extraction. - Highlights: • We tested a sequential extraction procedure for U-series isotope analysis on powdered rock standards (TML-3 and BCR-2) and a soil sample. • The leaching procedure does not impart any artifactual isotope fractionation to the sample. • Considerable

  11. A sequential extraction procedure to determine Ra and U isotopes by alpha-particle spectrometry in selective leachates

    International Nuclear Information System (INIS)

    A radiochemical sequential extraction procedure has been developed in our laboratory to determine 226Ra and 234,238U by alpha spectrometry in environmental samples. This method has been validated for both radionuclides by comparing in selected samples the values obtained through its application with the results obtained by applying alternative procedures. Recoveries obtained, counting periods applied and background levels found in the alpha spectra give suitable detection limits to allow the Ra and U determination in operational forms defined in riverbed contaminated sediments. Results obtained in these speciation studies show that 226Ra and 234,238U contamination tend to be associated to precipitated forms of the sediments. (author)

  12. Evaluating Specificity of Sequential Extraction for Chemical Forms of Lead in Artificially-contaminated and Field-contaminated Soils

    OpenAIRE

    Tai, Yiping; McBride, Murray B.

    2013-01-01

    In the present study, we evaluate a commonly employed a modified Bureau Communautaire de Référence (BCR test) 3-step sequential extraction procedure for its ability to distinguish forms of solid-phase Pb in soils with different sources and histories of contamination. When the modified BCR test was applied to mineral soils spiked with three forms of Pb (pyromorphite, hydrocerussite and nitrate salt), the added Pb was highly susceptible to dissolution in the operationally-defined “reducible” or...

  13. Assessment of electrokinetic removal of heavy metals from soils by sequential extraction analysis.

    Science.gov (United States)

    Reddy, K R; Xu, C Y; Chinthamreddy, S

    2001-06-29

    Electrokinetic remediation of metal-contaminated soils is strongly affected by soil-type and chemical species of contaminants. This paper investigates the speciation and extent of migration of heavy metals in soils during electrokinetic remediation. Laboratory electrokinetic experiments were conducted using two diverse soils, kaolin and glacial till, contaminated with chromium as either Cr(III) or Cr(VI). Initial total chromium concentrations were maintained at 1000mg/kg. In addition, Ni(II) and Cd(II) were used in concentrations of 500 and 250mg/kg, respectively. The contaminated soils were subjected to a voltage gradient of 1 VDC/cm for over 200h. The extent of migration of contaminants after the electric potential application was determined. Sequential extractions were performed on the contaminated soils before and after electrokinetic treatment to provide an understanding of the distribution of the contaminants in the soils. The initial speciation of contaminants was found to depend on the soil composition as well as the type and amounts of different contaminants present. When the initial form of chromium was Cr(III), exchangeable and soluble fractions of Cr, Ni, and Cd ranged from 10 to 65% in kaolin; however, these fractions ranged from 0 to 4% in glacial till. When the initial form of chromium was Cr(VI), the exchangeable and soluble fractions of Cr, Ni and Cd ranged from 66 to 80% in kaolin. In glacial till, however, the exchangeable and soluble fraction for Cr was 38% and Ni and Cd fractions were 2 and 10%, respectively. The remainder of the contaminants existed as the complex and precipitate fractions. During electrokinetic remediation, Cr(VI) migrated towards the anode, whereas Cr(III), Ni(II) and Cd(II) migrated towards the cathode. The speciation of contaminants after electrokinetic treatment showed that significant change in exchangeable and soluble fractions occurred. In kaolin, exchangeable and soluble Cr(III), Ni(II), and Cd(II) decreased near the

  14. Progress in field-assisted extraction and its application to solid sample analysis.

    Science.gov (United States)

    He, Yuanyuan; Xiao, Xiaohua; Cheng, Yingyi; Li, Gongke

    2016-01-01

    Sample preparation is the most time-consuming and laborious procedure during analysis. The rapid and effective extraction of solid and semi-solid samples is much more difficult than that of gas and liquid samples. In the present review, various extraction methods for solid and semi-solid samples such as supercritical fluid extraction, ultrasound-assisted extraction, microwave-assisted extraction, etc. are summarized based on the principles of field and field synergy effects. The expected trends of field-assisted extraction methods are discussed and proposed to encourage further development on the rapid and effective extraction for solid and semi-solid samples. PMID:26390199

  15. Ultrasound-Assisted Extraction (UAE) and Solvent Extraction of Papaya Seed Oil: Yield, Fatty Acid Composition and Triacylglycerol Profile

    OpenAIRE

    Hasanah Mohd Ghazali; Chin Ping Tan; Hamed Mirhosseini; Shadi Samaram

    2013-01-01

    The main objective of the current work was to evaluate the suitability of ultrasound-assisted extraction (UAE) for the recovery of oil from papaya seed as compared to conventional extraction techniques (i.e., Soxhlet extraction (SXE) and solvent extraction (SE)). In the present study, the recovery yield, fatty acid composition and triacylglycerol profile of papaya seed oil obtained from different extraction methods and conditions were compared. Results indicated that both solvent extraction (...

  16. Extraction of polyphenols from black tea--conventional and ultrasound assisted extraction.

    Science.gov (United States)

    Both, Simon; Chemat, Farid; Strube, Jochen

    2014-05-01

    Products from plant raw materials gain increasing importance in food-, cosmetics and pharmaceutical industry. By way of contrast, due to lack of detailed physico-chemical fundamentals, existing production processes are economically not optimal designed. This leads to a need for deeper understanding of the processes and furthermore a systematic process and equipment design for the potentially applicable extraction techniques. Using the example of polyphenol extraction from black tea (Kenya), the conventional and ultrasound assisted extractions are investigated. Here, the state of the art as well as a comparison between the two techniques is in focus. Especially, resulting quasi-equilibria and mass transport kinetics serves as a criteria. The physico-chemical background is discussed taking particle size distributions and scanning electron microscope (SEM) measurements into account. Conclusively, process alternatives are projected and discussed. Hence, the present study makes influences of ultrasound technique on physico-chemical characteristics during extraction a subject of discussion.

  17. Antibacterial activity of sequentially extracted organic solvent extracts of fruits, flowers and leaves of Lawsonia inermis L. from Jaffna

    Directory of Open Access Journals (Sweden)

    E Christy Jeyaseelan

    2012-10-01

    Conclusion: The study demonstrated that the ethyl acetate and ethanol extracts of fruit and flower of L. inermis are potentially better source of antibacterial agents compared to leaf extracts of respective solvents.

  18. Validation of a single-extraction procedure for sequential analysis of vitamin E, cholesterol, fatty acids, and total fat in seafood

    OpenAIRE

    Cruz, Rebeca; Casal, Susana; Mendes, Eulália; Costa, Ana; Santos, Catarina; Morais, Simone

    2013-01-01

    Food lipid major components are usually analyzed by individual methodologies using diverse extractive procedures for each class. A simple and fast extractive procedure was devised for the sequential analysis of vitamin E, cholesterol, fatty acids, and total fat estimation in seafood, reducing analyses time and organic solvent consumption. Several liquid/liquid-based extractive methodologies using chlorinated and non-chlorinated organic solvents were tested. The extract...

  19. Evaluating the performances of accelerated-solvent extraction, microwave-assisted extraction, and ultrasonic-assisted extraction for determining PCBs, HCHs and DDTs in sediments

    Institute of Scientific and Technical Information of China (English)

    ZHANG Peng; GE Linke; ZHOU Chuanguang; YAOZiwei

    2011-01-01

    Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments,i.e.accelerated solvent extraction (ASE),microwave assisted extraction (MAE) and ultrasonic assisted extraction (UAE).However,their extraction efficiencies have rarely been quantitatively compared using rigorous mathematical methods.In this paper,one-way analysis of variance (ANOVA) was employed to evaluate the performance of ASE,MAE and UAE in the overall extraction of PCBs,DDTs and HCHs by analysis of their recoveries from the Standard Reference Material IAEA-417,a sediment sample certified by many international laboratories.Conclusions were drawn at a significance level of P≤0.05.No significant differences were found among the mean values for method recoveries using ASE,MAE and UAE.The mean values for real recoveries using ASE and MAE were nearly identical,but the real recovery using UAE was much lower.The concentrations of all PCBs,DDTs and HCHs except for CB52 and o,p'-DDT using UAE were the lowest.Comparing the results obtained using ASE with MAE,the concentrations of CB28,CB52,CB138,α-HCH,β-HCH,p,p'-DDE and p,p'-DDD were nearly identical,while the concentrations of other compounds were significantly different.Based on the low recoveries,it was concluded that UAE is a relatively inefficient extraction method,while ASE and MAE are equivalent methods.Taking into consideration the relative standard deviation (RSD)values,solvent volume,extraction time,and purchasing costs of the apparatus,MAE was considered superior to ASE for extraction of PCBs,DDTs and HCHs.

  20. Sequential ultrasonic extraction of a Chinese coal and characterization of nitrogen-containing compounds in the extracts using high-performance liquid chromatography with mass spectrometry.

    Science.gov (United States)

    Xia, Jun-Liu; Fan, Xing; You, Chun-Yan; Wei, Xian-Yong; Zhao, Yun-Peng; Cao, Jing-Pei

    2016-07-01

    Dongming lignite was sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric carbon disulfide/acetone mixed solvent at room temperature to afford extracts 1-5, respectively. High-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry was used to separate and characterize heteroatomic species in the extracts at molecular level. Molecular mass of compounds in the extracts is mainly distributed from 300 to 800 u, and the relative abundance of compounds with molecular mass over 800 u in the carbon disulfide extract is 135 times of that in the petroleum ether extract. The acetone extract has the highest relative abundance for organonitrogen compounds. Double bond equivalence numbers of detected species indicate that most of the organonitrogen compounds contain N-heterocyclic aromatic rings, including pyridine, quinoline and pyrrole. Some organonitrogen isomers in Dongming lignite were separated and identified by high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry, and the corresponding structural information was proposed.

  1. A sequential extraction procedure for determination of uranium, thorium, radium, lead and polonium radionuclides by alpha spectrometry in environmental samples

    International Nuclear Information System (INIS)

    A sequential extraction technique was developed allowing the extraction and purification of uranium, thorium, radium, lead and polonium radionuclides from the same sample. Environmental materials such as water, soil, biological materials, can be analyzed for those radionuclides without matrix interferences in the quality of radioelement purification and in the radiochemical yield. The use of isotopic tracers (232U, 229Th, 224Ra, 209Po and stable lead carrier) added to the sample at the beginning of the chemical procedure enables an accurate control of the radiochemical yield for each radioelement. The ion extraction procedure, applied after either complete dissolution of the solid sample with mineral acids or dissolution of MnO2 precipitate for aqueous samples, includes the use of commercially available columns from Eichrom and laboratory prepared anionic and cationic columns, in a total of three chromatography columns. All radioelements are purified and electroplated on stainless steel discs except for polonium which is spontaneously plated on a silver disc. The discs are measured using high resolution silicon surface barrier detectors. 210Pb, a beta emitter, can be measured either through the beta emission of 210Bi, or stored for a few months and determined by alpha spectrometry through the in-growth of 210Po. This sequential extraction chromatography technique was tested and validated by analysis of certified reference materials from IAEA (soil, marine sediment, and fish). Reproducibility was tested through repeated analysis of the same homogeneous material (water sample). Performance, when applied to samples with different matrix, was tested analyzing cabbage, potatoes, fish filet, meat, water, urine, soils and sediments with high yield of recovery and complete separation of radioelements. Precision was tested also through participation in analytical inter laboratory world wide comparisons analysing blind samples (round robin tests) organized by the IAEA and

  2. Sequential automated fusion/extraction chromatography methodology for the dissolution of uranium in environmental samples for mass spectrometric determination

    International Nuclear Information System (INIS)

    An improved methodology has been developed, based on dissolution by automated fusion followed by extraction chromatography for the detection and quantification of uranium in environmental matrices by mass spectrometry. A rapid fusion protocol (2/LiBr melts were used. The use of a M4 fusion unit also improved repeatability in sample preparation over muffle furnace fusion. Instrumental issues originating from the presence of high salt concentrations in the digestate after lithium metaborate fusion was also mitigated using an extraction chromatography (EXC) protocol aimed at removing lithium and interfering matrix constituants prior to the elution of uranium. The sequential methodology, which can be performed simultaneously on three samples, requires less than 20 min per sample for fusion and separation. It was successfully coupled to inductively coupled plasma mass spectrometry (ICP-MS) achieving detection limits below 100 pg kg-1 for 5-300 mg of sample.

  3. Evaluation of uranium and arsenic retention by soil from a low level radioactive waste management site using sequential extraction

    Energy Technology Data Exchange (ETDEWEB)

    Evans, G.J.; Dhoum, R.T. [Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St. Toronto (Canada)

    1998-06-01

    The European Communities Bureau of Reference (BCR) and Chunguo sequential extraction procedures were employed to evaluate the retention of U and As by a soil contaminated with low level radioactive waste. Modifications were made to both procedures to optimize the measurement of soil and extractant samples using epithermal neutron activation analysis. Based on the BCR procedure, approximately 20% of the U appeared to be bound to the carbonate fraction, 10% to the mineral oxide fraction and 20% to the organic fraction. In the case of As, the majority was strongly bound in the residue fraction. The results obtained with the Chunguo procedure supported these conclusions to some extent, in that the majority of the U and As was found to be strongly bound to thesoil in a manner consistent with its presence in the residue fraction. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Evaluation of uranium and arsenic retention by soil from a low level radioactive waste management site using sequential extraction

    International Nuclear Information System (INIS)

    The European Communities Bureau of Reference (BCR) and Chunguo sequential extraction procedures were employed to evaluate the retention of U and As by a soil contaminated with low level radioactive waste. Modifications were made to both procedures to optimize the measurement of soil and extractant samples using epithermal neutron activation analysis. Based on the BCR procedure, approximately 20% of the U appeared to be bound to the carbonate fraction, 10% to the mineral oxide fraction and 20% to the organic fraction. In the case of As, the majority was strongly bound in the residue fraction. The results obtained with the Chunguo procedure supported these conclusions to some extent, in that the majority of the U and As was found to be strongly bound to the soil in a manner consistent with its presence in the residue fraction. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Optimization of microwave assisted extraction of pectin from orange peel.

    Science.gov (United States)

    Prakash Maran, J; Sivakumar, V; Thirugnanasambandham, K; Sridhar, R

    2013-09-12

    In this study, microwave-assisted extraction was applied for pectin extraction from the dried orange peel and Box-Behnken response surface design was used to study and optimize the effects of processing variables (microwave power, irradiation time, pH and solid-liquid ratio) on the yield of pectin. The amount of pectin extracted increased with increasing microwave power, while it reduces as the time, pH and solid-liquid ratio increased. From the results, second order polynomial model was developed and it adequately explained the data variation and significantly represented the actual relationship between independent variables and the response. An optimization study using Derringer's desired function methodology was performed and optimal conditions based on both individual and combinations of all independent variables (microwave power of 422W, irradiation time of 169 s, pH of 1.4 and solid-liquid ratio of 1:16.9 g/ml) were determined with maximum pectin yield of 19.24%, which was confirmed through validation experiments.

  6. Speciation of heavy metals by modified BCR sequential extraction procedure in different depths of sediments from Sungai Buloh, Selangor, Malaysia.

    Science.gov (United States)

    Nemati, Keivan; Abu Bakar, Nor Kartini; Abas, Mhd Radzi; Sobhanzadeh, Elham

    2011-08-15

    The sequential extraction procedure proposed by the European Standard, Measurements and Testing (SM&T) program, formerly the Community Bureau of Reference (BCR), was applied for partitioning of heavy metals (HMs) in river sediments collected along the course of Sungai Buloh and the Straits of Malacca in Selangor, Malaysia. Eight elements (V, Pb, Cd, Cr, Co, Ni, Cu and Zn) from seven stations (S1-S7) and at different depths were analyzed using the modified BCR Sequential Extraction Procedure (SEP) in combination with ICP-MS to obtain the metal distribution patterns in this region. The results showed that heavy metal contaminations at S2 and S3 was more severe than at other sampling sites, especially for Zn, Cu, Ni and Pb. Nevertheless, the element concentrations from top to bottom layers decreased predominantly. The samples from the Straits of Malacca (S4-S7) the highest contamination factors obtained were for Co, Zn and Pb while the lowest were found for V and Cr, similar to Sungai Buloh sediments. The sediments showed a low risk for V, Cr, Cu and Pb with RAC values of less than 10%, but medium risk for Co, Zn (except S3), Cd at S1 and S2 and Ni at S1, S3 and S5. Zn at S3 and Cd at S3-S7 showed high risk to our sediment samples. There is not any element of very high risk conditions in the selected samples.

  7. Sequential chemical extraction of heavy metals in a study of the chemical alteration of mine tailings at Ticapampa (Huaraz, Peru)

    International Nuclear Information System (INIS)

    The upper reaches of the Rio Santa (Huaraz, Peru) are highly affected by the mining activities of generally small and very small mining companies located in two specific areas, Cordillera Blanca, and Cordillera Negra, with the largest mining claims located in the districts of Recuay and Ticapampa. To assess the mobility and bioavailability of heavy metals in the abandoned tailings pond belonging to the Alianza mining company in the district of Ticapampa, and to identify the fractions to which they are associated we applied a sequential chemical extraction. The results were compared with studies into their mineralogical characterization, a quantitative chemical analysis and a determination of potential acidity and potential neutralization by the ABA (acid-base accounting) method applied to samples of tailings. The sequential extraction procedure confirmed the mode of general alteration observed in the area through mineralogical studies: a relatively easy mobility of Pb, and Cd, and considerable immobility with regard to Ag, Cr and Co, as well as an intermediate mobility of Cu, Zn, and As. Significant cadmium and lead contents found in the most mobile fractions of the tailings may represent an environmental threat, bearing in mind the toxic nature of these elements. Despite the low mobility of arsenic, the total quantities of this element are so high that the waters of the Rio Santa are being affected. (Author) 22 refs.

  8. Assessment of heavy metal pollution in sediments from Xiangjiang River (China) using sequential extraction and lead isotope analysis

    Institute of Scientific and Technical Information of China (English)

    蒋博峰; 孙卫玲

    2014-01-01

    The heavy metal (such as Cr, Ni, Cu, Cd, Pb, and Zn) concentration, speciation, and pollution source in 43 sediment samples from the Xiangjiang River were investigated using sequential extraction combined with Pb isotope analysis. Cu, Cd, Pb, and Zn concentrations are higher than their background values, while Cr and Ni concentrations are close to those. Sequential extraction demonstrates that heavy metals have different fractions, showing different bioavailabilities. Thew(206Pb)/w(207Pb) ratio increases with decreasing bioavailability in the order of exchangeable

  9. An innovative approach for sequential extraction of phosphorus in sediments: Ferrous iron P as an independent P fraction.

    Science.gov (United States)

    Gu, Sen; Qian, Yiguang; Jiao, Yang; Li, Qingman; Pinay, Gilles; Gruau, Gerard

    2016-10-15

    Accurate identification of phosphorus (P) forms is crucially important for understanding the geochemical cycle of P; however, until now the role of ferrous iron P (Fe(II)-P) buried in sediments has been completely ignored in nearly all sequential extraction procedures developed. Using sediment cores sampled from Donghu Lake in Wuhan, China, this study explored a modified version of widely used sequential P extraction method (SEDEX; Ruttenberg, 1992) in which Fe(II)-P was identified as an independent fraction. Based on the high selectivity of the extractant (0.2% 2,2'-bipyridine+0.1 M KCl) and the dissolution equilibrium of P, procedures for extracting Fe(II)-P were optimized using a 1:100 solid:liquid ratio and extraction at 50 ± 1 °C for 24 h. The sedimentary P extracted was divided into five fractions: loosely-bound P, Fe(II)-P, CDB-P, Ca-P and O-P. Fe(II)-P was the predominant fraction in fresh sediments in Donghu Lake, accounting for 15.7-49.9% of TP, with a mean of 31.6%. The mean values of Ca-P, O-P, CDB-P and loosely-bound P were 28.4%, 22.7%, 17.1% and 4.3%, respectively. Combined with component analysis of extracts and recovery experiments of standard reference minerals (vivianite, Fe3(PO4)2·8H2O) in natural sediments, extraction of Fe(II)-P with 0.2% 2,2-bipridine and 0.1 M KCl was robust, with a good recovery rate (88.7-100.6%) and little of the Ca-P dissolved. It is possible to use this innovative SEDEX not only to distinguish the contribution of different P matrices in fresh sediments, but also to investigate the transformation of sedimentary P under different redox conditions. Therefore, greater focus on Fe(II)-P is necessary, because it is a major sink for the geochemical process of sedimentary P.

  10. Distribution of Zinc and Cadmium in Tissues of Giant Reed (Arundo Donax L.: Sequential Extraction - Radiometric Study

    Directory of Open Access Journals (Sweden)

    Richveisová Barbora Micháleková

    2014-06-01

    Full Text Available Heavy metals are taken up by the vascular plant root system from water solutions in cationic forms. Subsequently, during both short and long distance transport to other plant tissues, cation forms are incorporated to many bioorganic compounds differing in stability, ionic character and physico-chemical properties such as solubility in lipid structures and mobility across cell membrane systems. Many sequential and single step extraction methods have been elaborated for characterization of the role of individual components of plant cells components in transport and detoxication of heavy metals. In our study, dry biomass of giant reed (Arundo donax L. grown in hydroponic media spiked with 65ZnCl2 and 109CdCl2 was treated with dithizone solutions as complexing ligand in order to convert free Zn2+ and Cd2+ ions to corresponding dithizonates. Treatment with dithizone showed that up to 67 % of the total plant Cd and 56 % of the total plant Zn were transformed to dithizonate complexes extracted with chloroform. Extraction of biomass with Folch reagent showed that up to 48 % of the total root cadmium and up to 18 % of the total shoot cadmium is bound in lipid fraction. Zinc was not found in lipid fraction of root and shoot. Derivatization of the dried root and shoot lipid fraction by dithizone showed that two third of Cd in root and practically all Cd in shoot lipid fraction could be transformed to Cd-dithizonate. Methods of biomass treating with complexing ligands and a method of sequential extraction procedures with non-polar organic solvents and radiotracer methodology seem to be useful methods for the study of metal speciation and distribution in vascular plants

  11. Sequential extraction procedure for determination of uranium, thorium, radium, lead and polonium radionuclides by alpha spectrometry in environmental samples

    International Nuclear Information System (INIS)

    A sequential extraction technique was developed and tested for common naturally-occurring radionuclides. This technique allows the extraction and purification of uranium, thorium, radium, lead, and polonium radionuclides from the same sample. Environmental materials such as water, soil, and biological samples can be analyzed for those radionuclides without matrix interferences in the quality of radioelement purification and in the radiochemical yield. The use of isotopic tracers (232U, 229Th, 224Ra, 209Po, and stable lead carrier) added to the sample in the beginning of the chemical procedure, enables an accurate control of the radiochemical yield for each radioelement. The ion extraction procedure, applied after either complete dissolution of the solid sample with mineral acids or co-precipitation of dissolved radionuclide with MnO2 for aqueous samples, includes the use of commercially available pre-packed columns from Eichrom(r) and ion exchange columns packed with Bio-Rad resins, in altogether three chromatography columns. All radioactive elements but one are purified and electroplated on stainless steel discs. Polonium is spontaneously plated on a silver disc. The discs are measured using high resolution silicon surface barrier detectors. 210Pb, a beta emitter, can be measured either through the beta emission of 210Bi, or stored for a few months and determined by alpha spectrometry through the in-growth of 210Po. This sequential extraction chromatography technique was tested and validated with the analysis of certified reference materials from the IAEA. Reproducibility was tested through repeated analysis of the same homogeneous material (water sample). (author)

  12. Fundamental Study on the Fabrication of Inverted Planar Perovskite Solar Cells Using Two-Step Sequential Substrate Vibration-Assisted Spray Coating (2S-SVASC)

    OpenAIRE

    Zabihi, Fatemeh; Ahmadian-Yazdi, Mohammad-Reza; Eslamian, Morteza

    2016-01-01

    In this paper, a scalable and fast process is developed and employed for the fabrication of the perovskite light harvesting layer in inverted planar heterojunction solar cell (FTO/PEDOT:PSS/CH3NH3PbI3−x Cl x /PCBM/Al). Perovskite precursor solutions are sprayed onto an ultrasonically vibrating substrate in two sequential steps via a process herein termed as the two-step sequential substrate vibration-assisted spray coating (2S-SVASC). The gentle imposed ultrasonic vibration on the substrate p...

  13. Sequential Data Mining for Information Extraction from Texts Fouille de données séquentielles pour l’extraction d’information dans les textes

    Directory of Open Access Journals (Sweden)

    Thierry Charnois

    2010-09-01

    Full Text Available This paper shows the benefit of using data mining methods for Biological Natural Language Processing. A method for discovering linguistic patterns based on a recursive sequential pattern mining is proposed. It does not require a sentence parsing nor other resource except a training data set. It produces understandable results and we show its interest in the extraction of relations between named entities. For the named entities recognition problem, we propose a method based on a new kind of patterns taking account the sequence and its context.

  14. Development of a sequential extraction method for different forms of phosphorus in Bovilla lake sediments

    OpenAIRE

    Loreta Vallja; , Sonila Duka; Alqi Cullaj

    2013-01-01

    Extractable forms of phosphorus are studied more widely than the extractable forms of most other elements. The main reason for this is because P is the key element in aquatic chemistry of lakes being a limiting nutrient in the growth of algae under many conditions. Exchange with bottom sediments place an important role in making P available for algae and contributes, therefore to eutrophication. Many extraction schemes have been developed to determine different forms of P in sediments. The ob...

  15. Ultrasound assisted extraction of lycopene from tomato processing wastes.

    Science.gov (United States)

    Kumcuoglu, Seher; Yilmaz, Tuncay; Tavman, Sebnem

    2014-12-01

    Tomato paste processing wastes, an important by-product of the paste industry, is rich in potentially health-promoting compounds such as lycopene. In this study, extraction yield of lycopene from tomato paste processing wastes by application of ultrasound assisted extraction (UAE) was compared with conventional organic solvent extraction (COSE) method. BHT (butylated hydroxytoluene) 0.05 % (w/v) added hexane:acetone:ethanol (2:1:1) mixture was used as solvent. Three different solvent solid ratios; 50:1, 35:1 and 20:1, (v/w) were used in both COSE and UAE. COSE experiments were performed at 20 °C, 40 °C and 60 °C for 10, 20, 30 and 40 min. 50, 65 and 90 W of ultrasonic power were applied in UAE for 1, 2, 5, 10, 15, 20 and 30 min. Lycopene contents of the samples were determined by spectrophotometric method. The effects of different factors, including the temperature, solvent solid ratio and ultrasonic power on lycopene yield were investigated. It was determined that the most efficient application for COSE was extracting samples by 50:1 solvent solid ratio at 60 °C for 40 min run, for UAE, 35:1 (v/w) solvent solid ratio, 90 W ultrasonic power for 30 min run. It was showed that UAE of lycopene requires less time, lower temperature and lower solvent than COSE. PMID:25477688

  16. Enrichment of antioxidant compounds from lemon balm (Melissa officinalis) by pressurized liquid extraction and enzyme-assisted extraction

    OpenAIRE

    Miron, T. L.; Herrero, Miguel; Ibáñez, Elena

    2013-01-01

    In this work enzyme-assisted extraction (EAE) and pressurized liquid extraction (PLE) are applied for extraction of natural compounds from lemon balm (Melissa officinalis). Cellulase, endo-β-1,4 xylanase and pectinase were studied in order to degrade cell wall of lemon balm leaves and to release phenolic compounds. On the other hand, in order to compare the performance obtained with EAE, PLE using water and ethanol was employed maintaining 150°C as extraction temperature. The obtained extract...

  17. Voltammetric behaviour at gold electrodes immersed in the BCR sequential extraction scheme media Application of underpotential deposition-stripping voltammetry to determination of copper in soil extracts

    International Nuclear Information System (INIS)

    The development of mercury-free electroanalytical systems for in-field analysis of pollutants requires a foundation on the electrochemical behaviour of the chosen electrode material in the target sample matrices. In this work, the behaviour of gold working electrodes in the media employed in the BCR sequential extraction protocol, for the fractionation of metals in solid environmental matrices, is reported. All three of the BCR sequential extraction media are redox active, on the basis of acidity and oxygen content as well as the inherent reducing or oxidising nature of some of the reagents employed: 0.11 M acetic acid, 0.1 M hydroxylammonium chloride (adjusted to pH 2) and 1 M ammonium acetate (adjusted to pH 2) with added trace hydrogen peroxide. The available potential ranges together with the demonstrated detection of target metals in these media are presented. Stripping voltammetry of copper or lead in the BCR extract media solutions reveal a multi-peak behaviour due to the stripping of both bulk metal and underpotential metal deposits. A procedure based on underpotential deposition-stripping voltammetry (UPD-SV) was evaluated for application to determination of copper in 0.11 M acetic acid soil extracts. A preliminary screening step in which different deposition times are applied to the sample enables a deposition time commensurate with UPD-SV to be selected so that no bulk deposition or stripping occurs thus simplifying the shape and features of the resulting voltammograms. Choice of the suitable deposition time is then followed by standards addition calibration. The method was validated by the analysis of a number of BCR 0.11 M acetic acid soil extracts. Good agreement was obtained been the UPD-SV method and atomic spectroscopic results

  18. On-line dynamic fractionation and automatic determination of inorganic phosphorous in environmental solid substrates exploiting sequential injection microcolumn extraction and flow injection analysi

    DEFF Research Database (Denmark)

    Buanuam, Janya; Miró, Manuel; Hansen, Elo Harald;

    2006-01-01

    Sequential injection microcolumn extraction (SI-MCE) based on the implementation of a soil containing microcartridge as external reactor in a sequential injection network is, for the first time, proposed for dynamic fractionation of macronutrients in environmental solids, as exemplified by the pa......Sequential injection microcolumn extraction (SI-MCE) based on the implementation of a soil containing microcartridge as external reactor in a sequential injection network is, for the first time, proposed for dynamic fractionation of macronutrients in environmental solids, as exemplified...... by the partitioning of inorganic phosphorous in agricultural soils. The on-line fractionation method capitalises on the accurate metering and sequential exposure of the various extractants to the solid sample by application of programmable flow as precisely coordinated by a syringe pump. Three different soil phase...... associations for phosphorus, that is, exchangeable, Al- and Fe-bound and Ca-bound fractions, were elucidated by accommodation in the flow manifold of the 3 steps of the Hietjles-Litjkema (HL) scheme involving the use of 1.0 M NH4Cl, 0.1 M NaOH and 0.5 M HCl, respectively, as sequential leaching reagents...

  19. Optimization of Microwave Assisted Extraction of Andrographolide from Andrographis paniculata and its Comparison with Refluxation Extraction Method

    Directory of Open Access Journals (Sweden)

    Manvitha Mohan

    2013-05-01

    Full Text Available A new method using Microwave assisted extraction technique has been developed for extraction of Andrographolide from Andrographis paniculata. Andrographis paniculata is a well-known plant of Ayurveda which is also known as king of bitters because of different bitter principles present in different parts of the plant and exhibits a wide spectrum of biological activities. The MAE conditions such as irradiation time, temperature and coarseness of powder were optimitized by means of orthogonal array design. The results suggested that the selected parameters were statistically significant. A comparative study was carried out to know the yield of andrographolide from the extracts prepared by microwave assisted extraction and refluxation using methanol and water as solvents. The amount of Andrographolide was estimated using HPTLC method. The results indicate that the extracts prepared by Microwave assisted extraction contained more amount of andrographolide when compared with refluxation extraction method.

  20. Comparative study of optimised BCR sequential extraction scheme and acid leaching of elements in the certified reference material NIST 2711

    International Nuclear Information System (INIS)

    The optimised BCR sequential extraction procedure and a 4 h 1 mol L-1 HCl partial extraction have been performed on the NIST 2711 reference material for a suite of 12 elements (Cd, Sb, Pb, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As) using magnetic sector ICP-MS. A pseudo-total aqua regia digest of NIST 2711 has also been undertaken for quality assurance purposes, and comparison of the sum of the four BCR fractions, which included an aqua regia digest on the residue, with the pseudo-total aqua regia digest has been used to assess the accuracy of the BCR partitioning approach. As a result of this work, discrepancies between previous studies about BCR partitioning of elements in NIST 2711 have been discussed and an increase in confidence about the use of BCR partitioning scheme on seven elements (Cd, Pb, Al, Mn, Fe, Cu, Zn) in this standard material has been obtained. On the other hand, BCR partitioning for Sb, Cr, Co, Ni and As has been provided for the first time. Partial extraction results are also reported for the same 12 elements analysed by the optimised BCR procedure, with the partial extraction results exhibiting a strong correlation with the sum of the three labile steps of the BCR procedure

  1. Sequential protein extraction as an efficient method for improved proteome coverage in larvae of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Nuez-Ortín, Waldo G; Carter, Chris G; Nichols, Peter D; Wilson, Richard

    2016-07-01

    Understanding diet- and environmentally induced physiological changes in fish larvae is a major goal for the aquaculture industry. Proteomic analysis of whole fish larvae comprising multiple tissues offers considerable potential but is challenging due to the very large dynamic range of protein abundance. To extend the coverage of the larval phase of the Atlantic salmon (Salmo salar) proteome, we applied a two-step sequential extraction (SE) method, based on differential protein solubility, using a nondenaturing buffer containing 150 mM NaCl followed by a denaturing buffer containing 7 M urea and 2 M thiourea. Extracts prepared using SE and one-step direct extraction were characterized via label-free shotgun proteomics using nanoLC-MS/MS (LTQ-Orbitrap). SE partitioned the proteins into two fractions of approximately equal amounts, but with very distinct protein composition, leading to identification of ∼40% more proteins than direct extraction. This fractionation strategy enabled the most detailed characterization of the salmon larval proteome to date and provides a platform for greater understanding of physiological changes in whole fish larvae. The MS data are available via the ProteomeXchange Consortium PRIDE partner repository, dataset PXD003366. PMID:27272914

  2. Extraction of bioactive carbohydrates from artichoke (Cynara scolymus L.) external bracts using microwave assisted extraction and pressurized liquid extraction.

    Science.gov (United States)

    Ruiz-Aceituno, Laura; García-Sarrió, M Jesús; Alonso-Rodriguez, Belén; Ramos, Lourdes; Sanz, M Luz

    2016-04-01

    Microwave assisted extraction (MAE) and pressurized liquid extraction (PLE) methods using water as solvent have been optimized by means of a Box-Behnken and 3(2) composite experimental designs, respectively, for the effective extraction of bioactive carbohydrates (inositols and inulin) from artichoke (Cynara scolymus L.) external bracts. MAE at 60 °C for 3 min of 0.3 g of sample allowed the extraction of slightly higher concentrations of inositol than PLE at 75 °C for 26.7 min (11.6 mg/g dry sample vs. 7.6 mg/g dry sample). On the contrary, under these conditions, higher concentrations of inulin were extracted with the latter technique (185.4 mg/g vs. 96.4 mg/g dry sample), considering two successive extraction cycles for both techniques. Both methodologies can be considered appropriate for the simultaneous extraction of these bioactive carbohydrates from this particular industrial by-product. To the best of our knowledge this is the first time that these techniques are applied for this purpose.

  3. Non-polar Solvent Microwave-Assisted Extraction of Volatile Constituents from Dried Zingiber Officinale Rosc.

    Institute of Scientific and Technical Information of China (English)

    YU Yong; WANG Zi-Ming; WANG Yu-Tang; LI Tie-Chun; CHENG Jian-Hua; LIU Zhong-Ying; ZHANG Han-Qi

    2007-01-01

    A new method, non-polar solvent microwave-assisted extraction (NPSMAE), was applied to the extraction of essential oil from Zingiber officinale Rosc. in closed-vessel system. By adding microwave absorption mediumcarbonyl iron powders (CIP) into extraction system, the essential oil was extracted by the non-polar solvent (ether)which can be heated by CIP. The constituents of essential oil obtained by NPSMAE were comparable with those obtained by hydrodistillation (HD) by GC-MS analysis, which indicates that NPSMAE is a feasible way to extract essential oil from dried plant materials. The NPSMAE took much less extraction time (5 min) than HD (180 min),and its extraction efficiency was much higher than that of conventional polar solvent microwave-assisted extraction (PSMAE) and mixed solvent microwave-assisted extraction (MSMAE). It can be a good alternative for the extraction of volatile constituents from dried plant samples.

  4. Enzyme-assisted extraction of stabilized chlorophyll from spinach.

    Science.gov (United States)

    Özkan, Gülay; Ersus Bilek, Seda

    2015-06-01

    Zinc complex formation with chlorophyll derivatives in spinach pulp was studied by adding 300ppm Zn(2+) for production of stable food colorant, followed by the heating at 110°C for 15min. Zinc complex formation increased at pH values of 7.0 or greater. Pectinex Ultra SP-L was selected for enzyme-assisted release of zinc-chlorophyll derivatives from spinach pulp. Effect of enzyme concentration (1-9%), treatment temperature (30-60°C), and time (30-210min) on total chlorophyll content (TCC) were optimized using response surface methodology. A quadratic regression model (R(2)=0.9486) was obtained from the experimental design. Optimum treatment conditions were 8% enzyme concentration, 45°C, and 30min, which yielded a 50.747mgTCC/100g spinach pulp. Enzymatic treatment was followed by solvent extraction with ethanol at a solvent-to-sample ratio of 2.5:1 at 60°C for 45min for the highest TCC recovery. Pretreatment with enzyme and extraction in ethanol resulted in 39% increase in Zn-chlorophyll derivative yield.

  5. Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae

    Institute of Scientific and Technical Information of China (English)

    LI Min-jing; YOU Jing-yan; YAO Shuang; DING Lan; LIU Zhong-ying; ZHANG Han-qi

    2004-01-01

    Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The third procedure was microwave resonant cavity dynamic extraction(MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other.

  6. Comparison of microwave and ultrasound-assisted extraction techniques for leaching of phenolic compounds from nettle

    OpenAIRE

    Ince, Alev Emine; Sahin, Serpil; Sumnu, Gulum

    2012-01-01

    In this study, extraction of phenolic compounds from nettle by microwave and ultrasound was studied. In both microwave and ultrasound-assisted extractions, effects of extraction time (5–20 min for microwave; 5–30 min for ultrasound) and solid to solvent ratio (1:10, 1:20, and 1:30 g/mL) on total phenolic content (TPC) were investigated. Effects of different powers (50 % and 80 %) were also studied for ultrasound-assisted extraction. In microwave-assisted extraction, the optimum TPC of the ext...

  7. Uranium distribution in mineral species of rocks by a sequential extraction procedure

    International Nuclear Information System (INIS)

    This work has the objective of measuring uranium series nuclides concentrations and calculating disequilibria in co-existing mineral species in order to clarify the uranium redistribution and the migration mechanicsm. The results to date indicate that the citrate-dithionite-bicarbonate extractable minerals (hematite and geothite) are the minerals most highly associated with uranium in the secondary ore deposit; that the 234U/238U activity ratios of Morgan's and Tamm's solution extractable minerals (adsorbed trace minerals and carbonates, and amorphous iron minerals) are less than unity, and are almost the same as in the groundwater (these minerals may be accessible to the groundwater); and that further investigation is required to confirm the extraction scheme, eg whether all uranium by Tamm's solution extraction is from amorphous iron and uranium silicates and phosphates. 11 refs., 1 tab., 5 figs

  8. Sequential Clustering based Facial Feature Extraction Method for Automatic Creation of Facial Models from Orthogonal Views

    CERN Document Server

    Ghahari, Alireza

    2009-01-01

    Multiview 3D face modeling has attracted increasing attention recently and has become one of the potential avenues in future video systems. We aim to make more reliable and robust automatic feature extraction and natural 3D feature construction from 2D features detected on a pair of frontal and profile view face images. We propose several heuristic algorithms to minimize possible errors introduced by prevalent nonperfect orthogonal condition and noncoherent luminance. In our approach, we first extract the 2D features that are visible to both cameras in both views. Then, we estimate the coordinates of the features in the hidden profile view based on the visible features extracted in the two orthogonal views. Finally, based on the coordinates of the extracted features, we deform a 3D generic model to perform the desired 3D clone modeling. Present study proves the scope of resulted facial models for practical applications like face recognition and facial animation.

  9. Sequential process for extraction and recovery of vanadium and uranium from wet process acids

    International Nuclear Information System (INIS)

    A process for preferentially extracting and recovering vanadium and uranium from wet process acids is claimed. The wet process acid first is contacted with a neutral organophosphorus compound to extract the vanadium values. The resulting loaded organic phase is separated from the wet process acid due to immiscibility of the acid and organic phases. The vanadium values then are separated from the organic phase by stripping. The raffinate separated from the first organic extractant then is contacted with a second organic extractant comprising a dialkyl-phosphoric acid and a neutral organo-phosphorus compound to extract the uranium values. The resulting loaded organic phase is separated from the wet process acid due to immiscibility of the acid and organic phases. The organic phase is stripped with a reductive stripping solution and the stripping solution then is oxidized to convert the uranium values to the hexavalent oxidation state. The oxidized solution then is contacted with another organic extractant to reextract the uranium to thereby concentrate the uranium product which then is stripped from the organic product with ammonium carbonate to form ammonium uranyl carbonate

  10. Optimization of Ultrasound-Assisted Extraction of Tannin from Cynomorium songaricum

    OpenAIRE

    Xiaoli Wang; Yanjun Jing; Xinqiang Zhu; Chunmei Wang; Yonggang Wang; Peng Lin; Lin Yang

    2015-01-01

    To optimize ultrasound-assisted extraction technology of tannin from the succulent stem of Cynomorium songaricum. The content of tannin in C. songaricum samples of different source was comparatively studied. Extraction rate of tannin as indexes, extraction process was optimized by single factor experiment and L9(34 orthogonal experiment. The best extraction technology for ultrasonic extraction were 75% as the extraction solvent ethanol concentration, 600 w as the ultrasonic power, 1:65 as the...

  11. Microwave-Assisted Extraction Studies of Target Analyte Artemisinin from Dried Leaves of Artemisia annua L.

    OpenAIRE

    Himanshu Misra; Darshana Mehta; B.K. Mehta; Jain, D. C.

    2013-01-01

    Artemisia annua L. (Asteraceae) is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. Conventional methods for the extraction of artemisinin from A. annua including solvent extraction, Soxhlet extraction, and heat reflux extraction are characterized by long extraction times and the consumption of large volume of solvents. A simple, rapid, and precise microwave-assisted extraction process was optimi...

  12. Comprehensive profiling of cartilage extracellular matrix formation and maturation using sequential extraction and label-free quantitative proteomics.

    Science.gov (United States)

    Wilson, Richard; Diseberg, Anders F; Gordon, Lavinia; Zivkovic, Snezana; Tatarczuch, Liliana; Mackie, Eleanor J; Gorman, Jeffrey J; Bateman, John F

    2010-06-01

    Articular cartilage is indispensable for joint function but has limited capacity for self-repair. Engineering of neocartilage in vitro is therefore a major target for autologous cartilage repair in arthritis. Previous analysis of neocartilage has targeted cellular organization and specific molecular components. However, the complexity of extracellular matrix (ECM) development in neocartilage has not been investigated by proteomics. To redress this, we developed a mouse neocartilage culture system that produces a cartilaginous ECM. Differential analysis of the tissue proteome of 3-week neocartilage and 3-day postnatal mouse cartilage using solubility-based protein fractionation targeted components involved in neocartilage development, including ECM maturation. Initially, SDS-PAGE analysis of sequential extracts revealed the transition in protein solubility from a high proportion of readily soluble (NaCl-extracted) proteins in juvenile cartilage to a high proportion of poorly soluble (guanidine hydrochloride-extracted) proteins in neocartilage. Label-free quantitative mass spectrometry (LTQ-Orbitrap) and statistical analysis were then used to filter three significant protein groups: proteins enriched according to extraction condition, proteins differentially abundant between juvenile cartilage and neocartilage, and proteins with differential solubility properties between the two tissue types. Classification of proteins differentially abundant between NaCl and guanidine hydrochloride extracts (n = 403) using bioinformatics revealed effective partitioning of readily soluble components from subunits of larger protein complexes. Proteins significantly enriched in neocartilage (n = 78) included proteins previously not reported or with unknown function in cartilage (integrin-binding protein DEL1; coiled-coil domain-containing protein 80; emilin-1 and pigment epithelium derived factor). Proteins with differential extractability between juvenile cartilage and neocartilage

  13. Recovery of Cobalt as Cobalt Oxalate from Cobalt Tailings Using Moderately Thermophilic Bioleaching Technology and Selective Sequential Extraction

    Directory of Open Access Journals (Sweden)

    Guobao Chen

    2016-07-01

    Full Text Available Cobalt is a very important metal which is widely applied in various critical areas, however, it is difficult to recover cobalt from minerals since there is a lack of independent cobalt deposits in nature. This work is to provide a complete process to recover cobalt from cobalt tailings using the moderately thermophilic bioleaching technology and selective sequential extraction. It is found that 96.51% Co and 26.32% Cu were extracted after bioleaching for four days at 10% pulp density. The mean compositions of the leach solutions contain 0.98 g·L−1 of Co, 6.52 g·L−1 of Cu, and 24.57 g·L−1 of Fe (III. The copper ion was then recovered by a solvent extraction process and the ferric ions were selectively removed by applying a goethite deironization process. The technological conditions of the above purification procedures were deliberately discussed. Over 98.6% of copper and 99.9% of ferric ions were eliminated from the leaching liquor. Cobalt was finally produced as cobalt oxalate and its overall recovery during the whole process was greater than 95%. The present bioleaching process of cobalt is worth using for reference to deal with low-grade cobalt ores.

  14. A comparison of an optimised sequential extraction procedure and dilute acid leaching of elements in anoxic sediments, including the effects of oxidation on sediment metal partitioning

    International Nuclear Information System (INIS)

    The effect of oxidation of anoxic sediment upon the extraction of 13 elements (Cd, Sn, Sb, Pb, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As) using the optimised Community Bureau of Reference of the European Commission (BCR) sequential extraction procedure and a dilute acid partial extraction procedure (4 h, 1 mol L-1 HCl) was investigated. Elements commonly associated with the sulfidic phase, Cd, Cu, Pb, Zn and Fe exhibited the most significant changes under the BCR sequential extraction procedure. Cd, Cu, Zn, and to a lesser extent Pb, were redistributed into the weak acid extractable fraction upon oxidation of the anoxic sediment and Fe was redistributed into the reducible fraction as expected, but an increase was also observed in the residual Fe. For the HCl partial extraction, sediments with moderate acid volatile sulfide (AVS) levels (1-100 μmol g-1) showed no significant difference in element partitioning following oxidation, whilst sediments containing high AVS levels (>100 μmol g-1) were significantly different with elevated concentrations of Cu and Sn noted in the partial extract following oxidation of the sediment. Comparison of the labile metals released using the BCR sequential extraction procedure (ΣSteps 1-3) to labile metals extracted using the dilute HCl partial extraction showed that no method was consistently more aggressive than the other, with the HCl partial extraction extracting more Sn and Sb from the anoxic sediment than the BCR procedure, whilst the BCR procedure extracted more Cr, Co, Cu and As than the HCl extraction

  15. Sequential recycling of enzymatic lipid-extracted hydrolysate in fermentations with a thraustochytrid.

    Science.gov (United States)

    Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

    2016-06-01

    This study extends the findings of prior studies proposing and validating nutrient recycling for the heterotrophic microalgae, Thraustochytrium sp. (T18), grown in optimized fed-batch conditions. Sequential nutrient recycling of enzymatically-derived hydrolysate in fermentors succeeded at growing the tested thraustochytrid strain, with little evidence of inhibition or detrimental effects upon culture health. The average maximum biomass obtained in the recycled hydrolysate was 63.68±1.46gL(-1) in 90h the first recycle followed by 65.27±1.15gL(-1) in 90h in the subsequent recycle of the same material. These compared to 58.59gL(-1) and 64.92gL(-1) observed in fresh media in the same time. Lipid production was slightly impaired, however, with a maximum total fatty acid content of 62.2±0.30% in the recycled hydrolysate compared to 69.4% in fresh control media. PMID:26994462

  16. Microwave-assisted extraction of alantolactone and isoalantolactone from inula helenium

    Directory of Open Access Journals (Sweden)

    Y M Zhao

    2015-01-01

    Full Text Available Microwave-assisted extraction was used for the extraction of alantolactone and isoalantolactone from Inula helenium. Effects of various experimental factors including ethanol concentration, particle size, microwave radiation time, the ratio of material to liquid and extraction temperature on yield of alantolactone and isoalantolactone were evaluated. The optimal extracting process of the alantolactone and isoalantolactone from the root of the Inula helenium was 1 g plant sample (sifted through 140 mesh mixed with 15 ml of 80% ethanol solution, microwave radiation 120 s at 50°. Under these optimal conditions, the yield of alantolactone and isoalantolactone was 31.83±2.08 mg/g and 21.25±1.37 mg/g, respectively. Compared with heat reflux extraction, ultrasound-assisted extraction, microwave-assisted extraction was more efficient and timesaving for the extraction of alantolactone and isoalantolactone from Inula helenium.

  17. Ultrasound-assisted extraction of ginseng saponins from ginseng roots and cultured ginseng cells.

    Science.gov (United States)

    Wu, J; Lin, L; Chau, F T

    2001-10-01

    Ultrasound-assisted extraction was evaluated as a simpler and more effective alternative to conventional extraction methods for the isolation of ginsenosides (saponins) from various types of ginseng. The ginseng samples were extracted with different solvents, under either direct sonication by an ultrasound probe horn or indirect sonication in an ultrasound cleaning bath. The ultrasonic extraction was compared with the conventional method of refluxing boiling solvents in a soxhlet extractor, on the yields of both the total saponin isolated by thin-layer chromatography and the individual ginsenosides by high performance liquid chromatography. It was found that the sonication-assisted extraction of ginseng saponins was about three times faster than the traditional extraction method. The ultrasonic extraction was not only more efficient but also convenient for the recovery and purification of the active ingredients of plant materials. In addition, the sonication-assisted extraction can be carried out at lower temperatures which are favorable for the thermally unstable compounds.

  18. Heavy Metal and Trace Metal Analysis in Soil by Sequential Extraction: A Review of Procedures

    OpenAIRE

    Amanda Jo Zimmerman; David C. Weindorf

    2010-01-01

    Quantification of heavy and trace metal contamination in soil can be arduous, requiring the use of lengthy and intricate extraction procedures which may or may not give reliable results. Of the many procedures in publication, some are designed to operate within specific parameters while others are designed for more broad application. Most procedures have been modified since their inception which creates ambiguity as to which procedure is most acceptable in a given situation. For this study, t...

  19. Application of rotating coiled columns to the fractionation of soil particles and to the sequential extraction of heavy-metal species from silty, dusty, and sandy fractions

    International Nuclear Information System (INIS)

    A complex procedure is developed for evaluating the degree of soil pollution with heavy metals, such as Zn, Pb, Cd, and Cu. Rotating coiled columns (RCCs) were used for both the fractionation of soil samples by their grain-size composition and the sequential extraction of heavy-metal species from silty, dusty, and sandy fractions. During the extraction of heavy-metal species, the soil fraction to be analyzed was retained in the column as a stationary phase, while aqueous solutions of extracting agents (mineral salts, acids, and complexing compounds) were sequentially pumped through the heterogeneous sample. The sequential extraction of element species from various soil fractions was carried out in the dynamic mode favorable to more complete extraction of metals. The use of RCCs allows the extraction of various heavy-metal species from soils to be performed in accordance with their grain size composition. The process of the extraction of metal species can be automated, and in this case the losses of sample components are reduced to a minimum

  20. Sequential extraction of heavy metals in river sediments of an abandoned pyrite mining area: pollution detection and affinity series

    International Nuclear Information System (INIS)

    In this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by superficial adsorption mechanisms. - Capsule: A modified Tessier's procedure, discriminating organic and sulphide bound metals, was used to detect pollutant mobilisation from red mud to river sediment in an abandoned pyrite mine

  1. Sequential cloud point extraction of trace elements from biological samples and determination by inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gine, Maria Fernanda; Patreze, Aparecida F.; Silva, Edson L. [Centro de Energia Nuclear na Agricultura (CENA-USP), Piracicaba, SP (Brazil)]. E-mail: mfgine@cena.usp.br; Sarkis, Jorge E.S.; Kakazu, Mauricio H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2008-07-01

    A two-step sequential cloud point extraction (CPE) of trace elements from small sample volumes of human serum, animal blood, and food diet is proposed to gain analytical information in the analysis by inductively coupled plasma mass spectrometry. The first CPE was attained by adding O,O-diethyldithiophosphate, the non ionic surfactant Triton{sup R} X-114 followed by heating at 40 deg C, centrifugation and cooling at 0 deg C. The resulting surfactant-rich phase was separated to determine Cd, Pb and Cu by isotope dilution. Isotope ratio measurements presented RSD < 0.7%. The residual surfactant-poor phase solution had the pH adjusted in the range 4 to 5 before the chelating reagent, 4-(2-pyridylazo) resorcinol plus surfactant Triton{sup R} X-114 were added followed by the sequence to attain the CPE. Co and Ni were quantified in the second extracted surfactant-rich phases by standard additions method with RSD < 2%. Recoveries from 85 to 96% were obtained for all elements. Analyzing reference materials with certified and recommended values assessed accuracy. (author)

  2. Sequential solvent extraction for the modes of occurrence of selenium in coals of different ranks from the Huaibei Coalfield, China

    Science.gov (United States)

    Zhang, Y.; Liu, Gaisheng; Chou, C.-L.; Wang, L.; Kang, Y.

    2007-01-01

    Forms of selenium in bituminous coal, anthracite, and cokeite (natural coke) from Huaibei Coalfield, Anhui, China, have been determined by sequential solvent extraction. The selenium content in bulk samples is 4.0, 2.4, and 2.0 ??g/g in bituminous coal, anthracite, and cokeite, respectively. The six forms of selenium determined by six-step solvent extraction are water-leachable, ion-exchangeable, organic matter-associated, carbonate-associated, silicate-associated, and sulfide-associated. The predominant forms of selenium in bituminous coal are organic matter-associated (39.0%), sulfide-associated (21.1%), and silicate bound (31.8%); these three forms account for 92% of the total. The organic matter bound-selenium decrease dramatically from bituminous coal (39.0%) to anthracite (11.6%) and to cokeite (0%), indicating that organic matter bound selenium is converted to other forms during metamorphism of the coal, most likely sulfide-form. The sulfide-associated form increased remarkably from bituminous coal (21.1%) to anthracite (50.4%) and cokeite (54.5%), indicating the formation of selenium sulfide, possibly in pyrite during the transformation of bituminous coal to anthracite and cokeite. The silicate-associated selenium in bituminous coal (31.8%) is much higher than that in anthracite (16.4%) and cokeite (15.8%), indicating that silicate-associated selenium is partly converted to sulfide during metamorphism. ?? 2007 Zhang et al; licensee BioMed Central Ltd.

  3. The use of a sequential extraction procedure for heavy metal analysis of house dusts by atomic absorption spectrometry.

    Science.gov (United States)

    Altundag, Huseyin; Dundar, Mustafa Sahin; Doganci, Secil; Celik, Muhammed; Tuzen, Mustafa

    2013-01-01

    In general, dust is considered as house or street dust. Indoor dust, as a contamination source, has been studied for many years. In this work, the original Community Bureau of Reference of the European Commission (BCR) three-stage sequential extraction procedure was applied to the fractionation of Cr, Cu, Fe, Mn, Pb, and Zn in 20 house dust samples from five different areas of Sakarya, Turkey. Acetic acid, hydroxylammonium chloride, and hydrogen peroxide plus ammonium acetate were used for the first, second, and third steps of the BCR method, respectively. The extracts were analyzed for the studied heavy metals using flame atomic absorption spectrometry. Validation of the results was performed by using a standard reference material (BCR 701 Sediment) to certify the experimental results obtained and to evaluate the reliability of the method used. The elemental loadings typically increased in magnitude according to the area order: Izmit Caddesi>Ankara Caddesi >Erenler>Karaman>Korucuk. The results were in agreement with values reported in the literature.

  4. Fate of mercury in flue gas desulfurization gypsum determined by Temperature Programmed Decomposition and Sequential Chemical Extraction.

    Science.gov (United States)

    Zhu, Zhenwu; Zhuo, Yuqun; Fan, Yaming; Wang, Zhipeng

    2016-05-01

    A considerable amount of Hg is retained in flue gas desulfurization (FGD) gypsum from Wet Flue Gas Desulfurization (WFGD) systems. For this reason, it is important to determine the species of Hg in FGD gypsum not only to understand the mechanism of Hg removal by WFGD systems but also to determine the final fate of Hg when FGD gypsum is disposed. In this study, Temperature Programmed Decomposition (TPD) and Sequential Chemical Extraction (SCE) were applied to FGD gypsum to identify the Hg species in it. The FGD gypsum samples were collected from seven coal-fired power plants in China, with Hg concentrations ranging from 0.19 to 3.27μg/g. A series of pure Hg compounds were used as reference materials in TPD experiments and the results revealed that the decomposition temperatures of different Hg compounds increase in the order of Hg2Cl2mercury sulfides were the primary compounds. The results of SCE indicated that Hg was mainly distributed in the strongly complexed phase. The low Hg content in FGD gypsum increases the ambiguity of assigning extraction fractions to certain Hg species by SCE. The fact that the primary compounds in FGD gypsum are HgS phases leads the leaching of Hg in the natural environment to be quite low, but a considerable amount of Hg may be released during the industrial heating process. PMID:27155422

  5. Ultrasound-Assisted Extraction of Total Phenolic Compounds from Inula helenium

    OpenAIRE

    Jin Wang; Yong-Ming Zhao; Ya-Ting Tian; Chun-Lin Yan; Chun-Yan Guo

    2013-01-01

    Ultrasound-assisted extraction (UAE) of phenolic compounds from Inula helenium was studied. Effects of ethanol concentration, ultrasonic time, solid-liquid ratio, and number of extractions were investigated. An orthogonal array was constructed to optimize UAE process. The optimized extraction conditions were as follows: ethanol concentration, 30%; solid-liquid ratio, 1 : 20; number of extractions, 2 times; extraction time, 30 min. Under the optimal conditions, the yield of total phenolic comp...

  6. Rapid Determination of Plutonium Isotopes in Environmental Samples Using Sequential Injection Extraction Chromatography and Detection by Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per;

    2009-01-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed by det...

  7. Multi-Elemental Inductively Coupled Plasma-Optical Emission Spectroscopic Calibration Problems of the Sequential Extraction Procedure for the Fractionation of the Heavy Metal Content from Aquatic Sediments

    OpenAIRE

    Heltai György; Fekete Ilona; Halász Gábor; Kovács Katalin (1978-) (biokémikus); Horváth Márk; Takács Anita; Boros Norbert; Győri Zoltán (1948-) (vegyész)

    2015-01-01

    For the characterisation of the environmental mobility of heavy metal contamination in aquatic sediments, the EU Bureau of Reference has proposed a fractionation by sequential extraction procedure. For its validation, the CRM-701 sample is available containing Cd, Cr, Cu, Ni, Pb, and Zn. In this paper, the matrix-matched calibration problems are presented. A multi-elemental inductively coupled plasma-optical emission technique is employed for the detection of heavy metals in the extracts. It ...

  8. Extraction of cocoa proanthocyanidins and their fractionation by sequential centrifugal partition chromatography and gel permeation chromatography.

    Science.gov (United States)

    Pedan, Vasilisa; Fischer, Norbert; Rohn, Sascha

    2016-08-01

    Cocoa beans contain secondary metabolites ranging from simple alkaloids to complex polyphenols with most of them believed to possess significant health benefits. The increasing interest in these health effects has prompted the need to develop techniques for their extraction, fractionation, separation, and analysis. This work provides an update on analytical procedures with a focus on establishing a gentle extraction technique. Cocoa beans were finely ground to an average particle size of centrifugal partition chromatography (SCPC) and gel permeation column chromatography using Sephadex LH-20. For SCPC, a two-phase solvent system consisting of ethyl acetate/n-butanol/water (4:1:5, v/v/v) was successfully applied for the separation of theobromine, caffeine, and representatives of the two main phenolic compound classes flavan-3-ols and flavonols. Gel permeation chromatography on Sephadex LH-20 using a stepwise elution sequence with aqueous acetone has been shown for effectively separating individual flavan-3-ols. Separation was obtained for (-)-epicatechin, proanthocyanidin dimer B2, trimer C1, and tetramer cinnamtannin A2. The purity of alkaloids and phenolic compounds was determined by HPLC analysis and their chemical identity was confirmed by mass spectrometry.

  9. Binary Solvent Extraction System and Extraction Time Effects on Phenolic Antioxidants from Kenaf Seeds (Hibiscus cannabinus L. Extracted by a Pulsed Ultrasonic-Assisted Extraction

    Directory of Open Access Journals (Sweden)

    Yu Hua Wong

    2014-01-01

    Full Text Available The aim of this study was to determine the best parameter for extracting phenolic-enriched kenaf (Hibiscus cannabinus L. seeds by a pulsed ultrasonic-assisted extraction. The antioxidant activities of ultrasonic-assisted kenaf seed extracts (KSE were determined by a 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging capacity assay, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS radical scavenging assay, β-carotene bleaching inhibition assay, and ferric reducing antioxidant power (FRAP assay. Total phenolic content (TPC and total flavonoid content (TFC evaluations were carried out to determine the phenolic and flavonoid contents in KSE. The KSE from the best extraction parameter was then subjected to high performance liquid chromatography (HPLC to quantify the phenolic compounds. The optimised extraction condition employed 80% ethanol for 15 min, with the highest values determined for the DPPH, ABTS, and FRAP assay. KSE contained mainly tannic acid (2302.20 mg/100 g extract and sinapic acid (1198.22 mg/100 g extract, which can be used as alternative antioxidants in the food industry.

  10. Rapid extraction of PCDD/Fs from soil and fly ash samples. Pressurized fluid extraction (PFE) and microwave-assisted extraction (MAE)

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, P.; Fabrellas, B. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Madrid (Spain)

    2004-09-15

    The main reference extraction method in the analysis of polychlorinated dibenzop- dioxins and dibenzofurans (PCDD/Fs) is still the Soxhlet extraction. But it requires long extraction times (up to 24 hs), large volumes of hazardous organic solvents (100-300 ml) and its automation is limited. Pressurized Fluid Extraction (PFE) and Microwave-Assisted Extraction (MAE) are two relatively new extraction techniques that reduce the time and the volume of solvent required for extraction. However, very different PFE extraction conditions are found for the same enviromental matrices in the literature. MAE is not a extraction technique very applied for the analysis of PCDD/Fs yet, although it is used for the determination of other organic compounds, such as PCBs and PAHs. In this study, PFE and MAE extraction conditions were optimized to determine PCDDs y PCDFs in fly ash and soil/sediment samples. Conventional Soxhlet extraction with toluene was used to compare the extraction efficiency of both techniques.

  11. Membrane contactor assisted extraction/reaction process employing ionic liquids

    Science.gov (United States)

    Lin, Yupo J.; Snyder, Seth W.

    2012-02-07

    The present invention relates to a functionalized membrane contactor extraction/reaction system and method for extracting target species from multi-phase solutions utilizing ionic liquids. One preferred embodiment of the invented method and system relates to an extraction/reaction system wherein the ionic liquid extraction solutions act as both extraction solutions and reaction mediums, and allow simultaneous separation/reactions not possible with prior art technology.

  12. OPTIMIZATION OF ULTRASOUND-ASSISTED EXTRACTION CONDITIONS OF FLAVONOIDS FROM TARTARY BUCKWHEAT

    Directory of Open Access Journals (Sweden)

    Zhang Zhong

    2012-12-01

    Full Text Available The objective of this study was to establish the optimum ultrasound-assisted extraction (UAE conditions for flavonoids from tartary buckwheat (FTB. Single factor experiments were performed to determine the appropriate range of extraction conditions and orthogonal experiment were performed to obtain the optimum extraction conditions. The results showed that the optimum UAE conditions for FTB were as followings: ethanol concentration of 65%, solid:liquid ratio of 1:40 g/ml, extraction time of 35 min and extraction temperature of 65 °C. UAE method is an alternative extraction technique for fast extraction of FTB.

  13. Comparative sorption and desorption behaviors of PFHxS and PFOS on sequentially extracted humic substances

    Institute of Scientific and Technical Information of China (English)

    Lixia Zhao; Yifeng Zhang; Shuhong Fang; Lingyan Zhu; Zhengtao Liu

    2014-01-01

    The sorption and desorption behaviors of two perfluoroalkane sulfonates (PFSAs),including perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) on two humic acids (HAs) and humin (HM),which were extracted from a peat soil,were investigated.The sorption kinetics and isotherms showed that the sorption of PFOS on the humic substances (HSs) was much higher than PFHxS.For the same PFSA compound,the sorption on HSs followed the order of HM > HA2 > HA1.These suggest that hydrophobic interaction plays a key role in the sorption of PFSAs on HSs.The sorption capacities of PFSAs on HSs were significantly related to their aliphaticity,but negatively correlated to aromatic carbons,indicating the importance of aliphatic groups in the sorption of PFSAs.Compared to PFOS,PFHxS displayed distinct desorption hysteresis,probably due to irreversible pore deformation after sorption of PFHxS.The sorption of the two PFSAs on HSs decreased with an increase in pH in the solution.This is ascribed to the electrostatic interaction and hydrogen bonding at lower pH.Hydrophobic interaction might also be stronger at lower pH due to the aggregation of HSs.

  14. Development of a rapid method for the sequential extraction and subsequent quantification of fatty acids and sugars from avocado mesocarp tissue.

    Science.gov (United States)

    Meyer, Marjolaine D; Terry, Leon A

    2008-08-27

    Methods devised for oil extraction from avocado (Persea americana Mill.) mesocarp (e.g., Soxhlet) are usually lengthy and require operation at high temperature. Moreover, methods for extracting sugars from avocado tissue (e.g., 80% ethanol, v/v) do not allow for lipids to be easily measured from the same sample. This study describes a new simple method that enabled sequential extraction and subsequent quantification of both fatty acids and sugars from the same avocado mesocarp tissue sample. Freeze-dried mesocarp samples of avocado cv. Hass fruit of different ripening stages were extracted by homogenization with hexane and the oil extracts quantified for fatty acid composition by GC. The resulting filter residues were readily usable for sugar extraction with methanol (62.5%, v/v). For comparison, oil was also extracted using the standard Soxhlet technique and the resulting thimble residue extracted for sugars as before. An additional experiment was carried out whereby filter residues were also extracted using ethanol. Average oil yield using the Soxhlet technique was significantly (P < 0.05) higher than that obtained by homogenization with hexane, although the difference remained very slight, and fatty acid profiles of the oil extracts following both methods were very similar. Oil recovery improved with increasing ripeness of the fruit with minor differences observed in the fatty acid composition during postharvest ripening. After lipid removal, methanolic extraction was superior in recovering sucrose and perseitol as compared to 80% ethanol (v/v), whereas mannoheptulose recovery was not affected by solvent used. The method presented has the benefits of shorter extraction time, lower extraction temperature, and reduced amount of solvent and can be used for sequential extraction of fatty acids and sugars from the same sample.

  15. Phenolic compounds and antioxidant activity of Pecan [Carya illinoinensis (Wangenh. C. Koch] kernel cake extracts obtained by sequential extraction

    Directory of Open Access Journals (Sweden)

    Block, Jane Mara

    2009-12-01

    Full Text Available The total phenolic and condensed tannin contents of different Pecan kernel cake extracts (ether, acetone, alcohol and distilled water were estimated and their antioxidant activities were evaluated through ABTS, DPPH and ß-carotene/linoleic acid systems. Color variations of the Pecan kernel cake were determined through an instrumental analysis using the CIE Lab system. Significantly higher levels (p El contenido de taninos condensado y fenoles totales de diferentes extractos de tortas de almendra de pecana (éter, acetona, alcohol y agua destilada fueron estimados y sus actividades antioxidantes fueron evaluadas mediantes los métodos con ABTS, DPPH y el sistema ß-caroteno/ácido linoleico. Las variaciones de color de la torta de almendra de pecana fueron determinadas mediante análisis instrumental usando el sistema CIE Lab. Los contenidos de fenoles totales, taninos condensados y actividad antioxidante, medida mediante los métodos con ABTS Y DPPH (30 min y 24 h, fueron significativamente más altos (p < 0.05 con el extracto de acetona (16.4 mg GAE/g; 31.2 mg CE/g; 235.3 μmol TEAC/g and 68.6 and 100.3 mg TEAC/g, respectivamente. El porcentaje de inhibición de la oxidación en el sistema ß-caroteno/ ácido linoleico vario desde 37.9 a 93.1% con el extracto de acetona a 300 ppm, mostrando resultados significativamente superiores. Las muestras con una mayor tendencia a tonos rojos presento los niveles más altos de taninos condensados.

  16. Microwave assisted extraction of sulfated polysaccharides (fucoidan) from Ascophyllum nodosum and its antioxidant activity.

    Science.gov (United States)

    Yuan, Yuan; Macquarrie, Duncan

    2015-09-20

    Sulfated polysaccharides (fucoidan) from brown seaweed Ascophyllum nodosum were extracted by microwave assisted extraction (MAE) technology. Different conditions of temperature (90-150°C), extraction time (5-30 min) were evaluated and optimal fucoidan yield was 16.08%, obtained from 120°C for 15 min's extraction. Compositional analysis, GPC, HPAEC and IR analysis were employed for characterization of extracted sulfated polysaccharides. Fucose was the main monosaccharide of fucoidan extracted at 90°C while glucuronic acid was the main monosaccharide of fucoidan extracted at 150°C. Both the molecular weight and sulfate content of extracted fucoidan increased with decreasing extraction temperature. All fucoidans exhibited antioxidant activities as measured by DPPH scavenging and reducing power, among which fucoidan extracted at 90°C was highest. This study shows that MAE is an efficient technology to extract sulfated polysaccharides from seaweed and Ascophyllum nodosum could potentially be a resource for natural antioxidants. PMID:26050894

  17. Speciation of Pb, Cu and Zn determined by sequential extraction for identification of air pollution sources in Syria

    Science.gov (United States)

    Al-Masri, M. S.; Al-Kharfan, K.; Al-Shamali, K.

    Speciation of three trace elements (Zn, Pb, Cu) in air particulates of two Syrian cities (Tartous and Darya) with different climate conditions and industrial emissions has been studied. Air filters were collected during 2000-2001 and extracted chemically using different selective fluids in an attempt to identify the different forms of trace elements. Approximately 60% of lead in air particulates of both cities was found to be associated with organic materials produced by incomplete burning of vehicles fuels and residential heating; the remaining 40% of lead was as lead oxides and mineral acids soluble compounds. Zinc was found in oxides (28-65%) samples collected in Tartous city, indicating that the Tartous cement factory and phosphate loading cargoes are the main source of emissions. In the Darya filters, zinc associated with organic materials (28-49%) was related to the presence of plastic molding industries and corroding car tires. In addition, copper was also found to be in the form of oxides (19-46%) in both cities in the summer periods, while 13-25% and 35% are associated with organic materials and silicates, respectively. Differences in chemical forms of the studied trace elements in air particulates were found to be related to differences in air pollution sources and differences in human behaviour throughout the year. Therefore, chemical fractionation of trace elements in air particulates using sequential leaching can be used for identification of air pollutions sources in urban and industrial areas.

  18. Speciation of potentially mobile Si in Yangtze Estuary surface sediments: estimates using a modified sequential extraction technique.

    Science.gov (United States)

    Zhu, Huagang; Wang, Chao; Wang, Peifang; Hou, Jun; Qian, Jin; Ao, Yanhui; Liu, Cui

    2016-09-01

    To improve our understanding of the Si-related biogeochemical processes that occur in estuarine ecosystems with large subaqueous deltas (e.g., the Yangtze Estuary; YE), the speciation of Si in the surface sediments of the YE was investigated. The relationships between the different Si species and sediment bulk parameters were also discussed. Based on modified sequential extraction method, we can successfully estimate the following five sedimentary potentially mobile Si pools: weak acid leachable Si (W-Si); Si bound to organic matter (H-Si); Si coprecipitated with amorphous Fe/Al oxides (O-Si); Si coprecipitated with crystalline Fe/Al oxides (Ouv-Si), and biogenic silica (B-Si). The total potentially mobile Si pool (T-Si) ranged between 1689.31 and 5487.10 μg/g, with high values observed in deltaic mud deposits. The Si fractions were closely correlated with grain size compositions, except for O-Si. In deltaic mud deposits, efficient loss of organic matters and recycling of Fe oxides probably resulted in the amorphous or poorly crystalline Fe oxides uncoupled with the clay fractions, and thus leading to the lack of correlation between O-Si and grain size. As compared with Ouv-Si, the O-Si should possess stronger mobility, which highlights the importance of quantifying the O-Si pool in deltaic sediments.

  19. Speciation of potentially mobile Si in Yangtze Estuary surface sediments: estimates using a modified sequential extraction technique.

    Science.gov (United States)

    Zhu, Huagang; Wang, Chao; Wang, Peifang; Hou, Jun; Qian, Jin; Ao, Yanhui; Liu, Cui

    2016-09-01

    To improve our understanding of the Si-related biogeochemical processes that occur in estuarine ecosystems with large subaqueous deltas (e.g., the Yangtze Estuary; YE), the speciation of Si in the surface sediments of the YE was investigated. The relationships between the different Si species and sediment bulk parameters were also discussed. Based on modified sequential extraction method, we can successfully estimate the following five sedimentary potentially mobile Si pools: weak acid leachable Si (W-Si); Si bound to organic matter (H-Si); Si coprecipitated with amorphous Fe/Al oxides (O-Si); Si coprecipitated with crystalline Fe/Al oxides (Ouv-Si), and biogenic silica (B-Si). The total potentially mobile Si pool (T-Si) ranged between 1689.31 and 5487.10 μg/g, with high values observed in deltaic mud deposits. The Si fractions were closely correlated with grain size compositions, except for O-Si. In deltaic mud deposits, efficient loss of organic matters and recycling of Fe oxides probably resulted in the amorphous or poorly crystalline Fe oxides uncoupled with the clay fractions, and thus leading to the lack of correlation between O-Si and grain size. As compared with Ouv-Si, the O-Si should possess stronger mobility, which highlights the importance of quantifying the O-Si pool in deltaic sediments. PMID:27335020

  20. Effects of modified zeolite on the removal and stabilization of heavy metals in contaminated lake sediment using BCR sequential extraction.

    Science.gov (United States)

    Wen, Jia; Yi, Yuanjie; Zeng, Guangming

    2016-08-01

    Sediment can be applied on land as a soil conditioner. However, toxic substances such as heavy metals within the sediment often lead to soil contamination if no proper management is conducted prior to land application. In order to reduce the bioavailable portion of heavy metals such as Pb, Cu, Zn and Cd, zeolite as a kind of stabilizer was investigated on the effect of metal stabilization in sediment. Zeolite was firstly modified and screened to get the best condition for removal of heavy metals. Results showed that the granulated zeolite with NaCl conditioning had the highest CEC and metal sorption. Using BCR sequential extraction, the selected modified zeolite effectively stabilized Pb, Cu, Zn and Cd in sediment to different extents. It was most suitable for Cd stabilization by reducing its acid exchangeable fraction while increasing the contents of the reducible and residual fractions. Modified zeolite also immobilized Cu, Zn and Pb in sediment by enhancing one stable fraction while decreasing the acid exchangeable fraction. PMID:27136618

  1. Assessment of metal species in river Ganga sediment at Varanasi, India using sequential extraction procedure and SEM-EDS.

    Science.gov (United States)

    Pandey, Mayank; Pandey, Ashutosh Kumar; Mishra, Ashutosh; Tripathi, B D

    2015-09-01

    Aim of the present study was to assess impact of urban drains over river water and sediments by physico-chemical and metal analysis. Metal speciation (Sequential Extraction Procedure) and elemental composition analysis (SEM-EDS) was used to quantify metal pollution load in river sediments. Metal speciation analysis showed dominance of available and labile fractions of all heavy metals (Cr, Ni, Cu, Zn, Cd and Pb) except Mn and Fe which were dominant in residual forms. Cluster analysis (CA), Principal Components Analysis (PCA) and Partial Least Square Regression (PLSR) were applied as source receptor modeling for pollutants. Results classified river stretch into three zones i.e. moderately, severely and extremely polluted, on the basis of pollutant concentration released from anthropogenic sources. SEM-EDS study revealed the elemental composition percentage in river sediments. Pollution Load Index (PLI) varied from 1.8 (S1)-3.9 (S15). The Geo accumulation index (GAI) was found highest for Cd (6.88-8.97) and Pb (2.41-3.24).

  2. Solid sample graphite furnace atomic absorption spectroscopy for supporting arsenic determination in sediments following a sequential extraction procedure

    International Nuclear Information System (INIS)

    Solid sample graphite furnace atomic absorption spectroscopy (SS-GFAAS) has been proposed since its appearance as a good alternative to wet methods of analysis in many matrices. Here, we examine the use of SS-GFAAS for total and leachable arsenic determination in sediments from distinct origins. Our direct analysis of seven selected sediments was not always free of spectral matrix interference, but the spectroscopic technique gave very good results for (a) direct arsenic measurement in solid residues from a range of leaching processes, (b) total arsenic determination (HNO3 leaching test) and (c) the evaluation of its potential remobilisation (modified BCR three-step sequential extraction scheme). For the optimised instrumental conditions, the analysis limit was 0.44 mg kg-1 and long-term reproducibility was between 10-15%. The sum of leachable arsenic in HNO3 65% and the residual fraction, gave recoveries from 72 to 118% of total arsenic content. These results are a good alternative to other cumbersome wet methods involving HF

  3. Sequential Extraction on Oil Sandstones from TZ401 Well——A Case Study on Filling History of Hydrocarbon Reservoir

    Institute of Scientific and Technical Information of China (English)

    Pan Changchun; Liu Dayong

    2008-01-01

    Sequential extraction was performed on two oil sandstones from the Upper Carboniferous oil columns of TZ401 well.The free oils of these two oil sandstones and a crude oil from the Lower Carboniferous oil column of this well have low ratios of C28/C27+C28+ C29) steranes and gammacerane/C31 hopanes,ranging of 0.11-0.16 and 0.09-0.15,respectively,similar to those from the Middle-Upper Ordovician source rock.However,these two ratios for the adsorbed and inclusion oils of these two oil sandstones are relatively high,ranging of 0.29-0.31 and 0.26-0.40,respectively,similar to those of the Cambrian-Lower Ordovician source rock.This result demonstrates that the initial oil charging the reservoirs was derived from the Cambrian-Lower Ordovician source rock,whereas the later charging oil was derived from the Middle--Upper Ordovician source rock.

  4. Speciation of Heavy Metals by Modified BCR Sequential Extraction in Soils Contaminated by Phosphogypsum in Sfax, Tunisia

    Directory of Open Access Journals (Sweden)

    Ahmed Wali

    2015-01-01

    Full Text Available The accumulation of trace metals in soil is a serious environmental problem that creates a hazard when metals are transferred to water or plants. To understand the mobility and bioavailability of trace metals, the concentrations and distributions of trace metals must be established for different physical and chemical phases of the soil. We determined the concentrations of trace metals (Zn, Pb, Cu, Cr, Co, Ni, Mn, and Fe in soil using the sequential extraction method recommended by Community Bureau of Reference (BCR and analysed chemical properties, such as the pH, cation exchange capacity, total organic carbon, electrical conductivity, and calcium carbonate. Our results revealed higher concentrations of trace metals in topsoil samples (0–20 cm than in subsoil samples (20–40 cm and 40–60 cm for most metals at four sites. Zn in the topsoil was mostly associated with the non-resistant fraction at all sites. Approximately 60% more Pb was bound to the non-residual, exchangeable and reducible fractions at all sites, and soil depths. Cr, Cu, Ni and Fe were mainly in the residual fraction, whereas Mn was largely present in the non-resistant fraction. The global contamination factor of trace metals decreased with soil depth. The mobility and bioavailability were greatest for Zn, followed by Cu and Pb. DOI: http://dx.doi.org/10.5755/j01.erem.70.4.7807

  5. Effects of modified zeolite on the removal and stabilization of heavy metals in contaminated lake sediment using BCR sequential extraction.

    Science.gov (United States)

    Wen, Jia; Yi, Yuanjie; Zeng, Guangming

    2016-08-01

    Sediment can be applied on land as a soil conditioner. However, toxic substances such as heavy metals within the sediment often lead to soil contamination if no proper management is conducted prior to land application. In order to reduce the bioavailable portion of heavy metals such as Pb, Cu, Zn and Cd, zeolite as a kind of stabilizer was investigated on the effect of metal stabilization in sediment. Zeolite was firstly modified and screened to get the best condition for removal of heavy metals. Results showed that the granulated zeolite with NaCl conditioning had the highest CEC and metal sorption. Using BCR sequential extraction, the selected modified zeolite effectively stabilized Pb, Cu, Zn and Cd in sediment to different extents. It was most suitable for Cd stabilization by reducing its acid exchangeable fraction while increasing the contents of the reducible and residual fractions. Modified zeolite also immobilized Cu, Zn and Pb in sediment by enhancing one stable fraction while decreasing the acid exchangeable fraction.

  6. Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG

    Directory of Open Access Journals (Sweden)

    Kwang Jin Lee

    2016-07-01

    Full Text Available Fetal heart rate (FHR is an important determinant of fetal health. Cardiotocography (CTG is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB. Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR.

  7. Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG.

    Science.gov (United States)

    Lee, Kwang Jin; Lee, Boreom

    2016-01-01

    Fetal heart rate (FHR) is an important determinant of fetal health. Cardiotocography (CTG) is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs) from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB). Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR. PMID:27376296

  8. Assessment of metal species in river Ganga sediment at Varanasi, India using sequential extraction procedure and SEM-EDS.

    Science.gov (United States)

    Pandey, Mayank; Pandey, Ashutosh Kumar; Mishra, Ashutosh; Tripathi, B D

    2015-09-01

    Aim of the present study was to assess impact of urban drains over river water and sediments by physico-chemical and metal analysis. Metal speciation (Sequential Extraction Procedure) and elemental composition analysis (SEM-EDS) was used to quantify metal pollution load in river sediments. Metal speciation analysis showed dominance of available and labile fractions of all heavy metals (Cr, Ni, Cu, Zn, Cd and Pb) except Mn and Fe which were dominant in residual forms. Cluster analysis (CA), Principal Components Analysis (PCA) and Partial Least Square Regression (PLSR) were applied as source receptor modeling for pollutants. Results classified river stretch into three zones i.e. moderately, severely and extremely polluted, on the basis of pollutant concentration released from anthropogenic sources. SEM-EDS study revealed the elemental composition percentage in river sediments. Pollution Load Index (PLI) varied from 1.8 (S1)-3.9 (S15). The Geo accumulation index (GAI) was found highest for Cd (6.88-8.97) and Pb (2.41-3.24). PMID:26011279

  9. Enzyme-Assisted Extraction of Oil from Wet Microalgae Scenedesmus sp. G4

    OpenAIRE

    Shuhao Huo; Zhongming Wang; Fengjie Cui; Bin Zou; Pengxiang Zhao; Zhenhong Yuan

    2015-01-01

    The enzyme-assisted aqueous extraction of oil from wet microalgae was employed to avoid the energy consumption of a dewatering process. In this paper, oil-rich microalgae Scenedesmus sp. G4 was hydrolyzed by enzyme mixtures for oil extraction. The results showed that the algae concentration had the greatest influence on yield of extracted oil, and the temperature and the ratio of enzyme mixtures affected the results as follows: the maximum yield of oil extracted from Scenedesmus sp. G4 reache...

  10. Response Surface Methodology for Ultrasound-Assisted Extraction of Astaxanthin from Haematococcus pluvialis

    OpenAIRE

    Hong-Fu Wu; Chang-Xiu Wang; Hua-Wen Li; Tang-Bin Zou; Qing Jia

    2013-01-01

    Astaxanthin is a novel carotenoid nutraceutical occurring in many crustaceans and red yeasts. It has exhibited various biological activities including prevention or amelioration of cardiovascular disease, gastric ulcer, hypertension, and diabetic nephropathy. In this study, ultrasound-assisted extraction was developed for the effective extraction of astaxanthin from Haematococcus pluvialis. Some parameters such as extraction solvent, liquid-to-solid ratio, extraction temperature, and extracti...

  11. OPTIMIZATION OF ULTRASOUND-ASSISTED EXTRACTION CONDITIONS OF FLAVONOIDS FROM TARTARY BUCKWHEAT

    OpenAIRE

    Zhang Zhong

    2012-01-01

    The objective of this study was to establish the optimum ultrasound-assisted extraction (UAE) conditions for flavonoids from tartary buckwheat (FTB). Single factor experiments were performed to determine the appropriate range of extraction conditions and orthogonal experiment were performed to obtain the optimum extraction conditions. The results showed that the optimum UAE conditions for FTB were as followings: ethanol concentration of 65%, solid:liquid ratio of 1:40 g/ml, extraction time of...

  12. Microwave-assisted Extraction of Alantolactone and Isoalantolactone from Inula helenium

    OpenAIRE

    Zhao, Y. M.; Wang, J.; Liu, H. B.; C Y Guo; Zhang, W. M.

    2015-01-01

    Microwave-assisted extraction was used for the extraction of alantolactone and isoalantolactone from Inula helenium. Effects of various experimental factors including ethanol concentration, particle size, microwave radiation time, the ratio of material to liquid and extraction temperature on yield of alantolactone and isoalantolactone were evaluated. The optimal extracting process of the alantolactone and isoalantolactone from the root of the Inula helenium was 1 g plant sample (sifted throug...

  13. Ultrasound-Assisted Extraction of Mangiferin from Mango (Mangifera indica L.) Leaves Using Response Surface Methodology

    OpenAIRE

    Zou, Tang-Bin; Xia, En-Qin; He, Tai-Ping; Huang, Ming-Yuan; Jia, Qing; Li, Hua-Wen

    2014-01-01

    Mangiferin is a xanthone widely distributed in higher plants showing antioxidative, antiviral, anticancer, antidiabetic, immunomodulatory, hepatoprotective and analgesic effects. In the present study, an ultrasonic-assisted extraction method was developed for the effective extraction of mangiferin from mango leaves. Some parameters such as ethanol concentration, liquid-to-solid ratio, extraction temperature, and extraction time were optimized by single-factor experiment and response surface m...

  14. Microwave-assisted extraction of anthocyanin from Chinese bayberry and its effects on anthocyanin stability

    OpenAIRE

    Wenkai DUAN; Jin, Shiping; Guofu ZHAO; SUN, PEILONG

    2015-01-01

    AbstractAnthocyanins are present in high concentrations in Chinese bayberry, Myrica rubra Sieb. & Zucc. Herein, a microwave-assisted extraction was used to extract the anthocyanins from Chinese bayberry. The HPLC chromatogram of the extracts showed that the anthocyanin components were slightly hydrolysed during the extraction process. Further experiments confirmed that microwave irradiation slightly hydrolysed cyanidin-3-O-glucoside to cyanidin, but did not significantly influence the antioxi...

  15. A novel enzyme-assisted ultrasonic approach for highly efficient extraction of resveratrol from Polygonum cuspidatum.

    Science.gov (United States)

    Lin, Jer-An; Kuo, Chia-Hung; Chen, Bao-Yuan; Li, Ying; Liu, Yung-Chuan; Chen, Jiann-Hwa; Shieh, Chwen-Jen

    2016-09-01

    Resveratrol is a promising multi-biofunctional phytochemical, which is abundant in Polygonum cuspidatum. Several methods for resveratrol extraction have been reported, while they often take a long extraction time accompanying with poor extraction yield. In this study, a novel enzyme-assisted ultrasonic approach for highly efficient extraction of resveratrol from P. cuspidatum was developed. According to results, the resveratrol yield significantly increased after glycosidases (Pectinex® or Viscozyme®) were applied in the process of extraction, and better extraction efficacy was found in the Pectinex®-assisted extraction compared to Viscozyme®-assisted extraction. Following, a 5-level-4-factor central composite rotatable design with response surface methodology (RSM) and artificial neural network (ANN) was selected to model and optimize the Pectinex®-assisted ultrasonic extraction. Based on the coefficient of determination (R(2)) calculated from the design data, ANN model displayed much more accurate in data fitting as compared to RSM model. The optimum conditions for the extraction determined by ANN model were substrate concentration of 5%, acoustic power of 150W, pH of 5.4, temperature of 55°C, the ratio of enzyme to substrate of 3950 polygalacturonase units (PGNU)/g of P. cuspidatum, and reaction time of 5h, which can lead to a significantly high resveratrol yield of 11.88mg/g.

  16. Optimization of microwave-assisted enzymatic extraction of polysaccharides from the fruit of Schisandra chinensis Baill.

    Science.gov (United States)

    Cheng, Zhenyu; Song, Haiyan; Yang, Yingjie; Liu, Yan; Liu, Zhigang; Hu, Haobin; Zhang, Yang

    2015-05-01

    A microwave-assisted enzymatic extraction (MAEE) method had been developed, which was optimized by response surface methodology (RSM) and orthogonal test design, to enhance the extraction of crude polysaccharides (CPS) from the fruit of Schisandra chinensis Baill. The optimum conditions were as follows: microwave irradiation time of 10 min, extraction pH of 4.21, extraction temperature of 47.58°C, extraction time of 3h and enzyme concentration of 1.5% (wt% of S. chinensis powder) for cellulase, papain and pectinase, respectively. Under these conditions, the extraction yield of CPS was 7.38 ± 0.21%, which was well in close agreement with the value predicted by the model. The three methods including heat-refluxing extraction (HRE), ultrasonic-assisted extraction (UAE) and enzyme-assisted extraction (EAE) for extracting CPS by RSM were further compared. Results indicated MAEE method had the highest extraction yields of CPS at lower temperature. It was indicated that the proposed approach in this study was a simple and efficient technique for extraction of CPS in S. chinensis Baill.

  17. Application of ionic liquids based enzyme-assisted extraction of chlorogenic acid from Eucommia ulmoides leaves.

    Science.gov (United States)

    Liu, Tingting; Sui, Xiaoyu; Li, Li; Zhang, Jie; Liang, Xin; Li, Wenjing; Zhang, Honglian; Fu, Shuang

    2016-01-15

    A new approach for ionic liquid based enzyme-assisted extraction (ILEAE) of chlorogenic acid (CGA) from Eucommia ulmoides is presented in which enzyme pretreatment was used in ionic liquids aqueous media to enhance extraction yield. For this purpose, the solubility of CGA and the activity of cellulase were investigated in eight 1-alkyl-3-methylimidazolium ionic liquids. Cellulase in 0.5 M [C6mim]Br aqueous solution was found to provide better performance in extraction. The factors of ILEAE procedures including extraction time, extraction phase pH, extraction temperatures and enzyme concentrations were investigated. Moreover, the novel developed approach offered advantages in term of yield and efficiency compared with other conventional extraction techniques. Scanning electronic microscopy of plant samples indicated that cellulase treated cell wall in ionic liquid solution was subjected to extract, which led to more efficient extraction by reducing mass transfer barrier. The proposed ILEAE method would develope a continuous process for enzyme-assisted extraction including enzyme incubation and solvent extraction process. In this research, we propose a novel view for enzyme-assisted extraction of plant active component, besides concentrating on enzyme facilitated cell wall degradation, focusing on improvement of bad permeability of ionic liquids solutions.

  18. Preliminary study: kinetics of oil extraction from sandalwood by microwave-assisted hydrodistillation

    Science.gov (United States)

    Kusuma, H. S.; Mahfud, M.

    2016-04-01

    Sandalwood and its oil, is one of the oldest known perfume materials and has a long history (more than 4000 years) of use as mentioned in Sanskrit manuscripts. Sandalwood oil plays an important role as an export commodity in many countries and its widely used in the food, perfumery and pharmaceuticals industries. The aim of this study is to know and verify the kinetics and mechanism of microwave-assisted hydrodistillation of sandalwood based on a second-order model. In this study, microwave-assisted hydrodistillation is used to extract essential oils from sandalwood. The extraction was carried out in ten extraction cycles of 15 min to 2.5 hours. The initial extraction rate, the extraction capacity and the second-order extraction rate constant were calculated using the model. Kinetics of oil extraction from sandalwood by microwave-assisted hydrodistillation proved that the extraction process was based on the second-order extraction model as the experimentally done in three different steps. The initial extraction rate, h, was 0.0232 g L-1 min-1, the extraction capacity, C S, was 0.6015 g L-1, the second-order extraction rate constant, k, was 0.0642 L g-1 min-1 and coefficient of determination, R 2, was 0.9597.

  19. Fundamental Study on the Fabrication of Inverted Planar Perovskite Solar Cells Using Two-Step Sequential Substrate Vibration-Assisted Spray Coating (2S-SVASC).

    Science.gov (United States)

    Zabihi, Fatemeh; Ahmadian-Yazdi, Mohammad-Reza; Eslamian, Morteza

    2016-12-01

    In this paper, a scalable and fast process is developed and employed for the fabrication of the perovskite light harvesting layer in inverted planar heterojunction solar cell (FTO/PEDOT:PSS/CH3NH3PbI3-x Cl x /PCBM/Al). Perovskite precursor solutions are sprayed onto an ultrasonically vibrating substrate in two sequential steps via a process herein termed as the two-step sequential substrate vibration-assisted spray coating (2S-SVASC). The gentle imposed ultrasonic vibration on the substrate promotes droplet spreading and coalescence, surface wetting, evaporation, mixing of reagents, and uniform growth of perovskite nanocrystals. The role of the substrate temperature, substrate vibration intensity, and the time interval between the two sequential sprays are studied on the roughness, coverage, and crystalline structure of perovskite thin films. We demonstrate that a combination of a long time interval between spraying of precursor solutions (15 min), a high substrate temperature (120 °C), and a mild substrate vibration power (5 W) results in a favorable morphology and surface quality. The characteristics and performance of prepared perovskite thin films made via the 2S-SVASC technique are compared with those of the co-sprayed perovskite thin films. The maximum power conversion efficiency of 5.08 % on a 0.3-cm(2) active area is obtained for the device made via the scalable 2S-SVASC technique. PMID:26847697

  20. Soxhlet-assisted matrix solid phase dispersion to extract flavonoids from rape (Brassica campestris) bee pollen.

    Science.gov (United States)

    Ma, Shuangqin; Tu, Xijuan; Dong, Jiangtao; Long, Peng; Yang, Wenchao; Miao, Xiaoqing; Chen, Wenbin; Wu, Zhenhong

    2015-11-15

    Soxhlet-assisted matrix solid phase dispersion (SA-MSPD) method was developed to extract flavonoids from rape (Brassica campestris) bee pollen. Extraction parameters including the extraction solvent, the extraction time, and the solid support conditions were investigated and optimized. The best extraction yields were obtained using ethanol as the extraction solvent, silica gel as the solid support with 1:2 samples to solid support ratio, and the extraction time of one hour. Comparing with the conventional solvent extraction and Soxhlet method, our results show that SA-MSPD method is a more effective technique with clean-up ability. In the test of six different samples of rape bee pollen, the extracted content of flavonoids was close to 10mg/g. The present work provided a simple and effective method for extracting flavonoids from rape bee pollen, and it could be applied in the studies of other kinds of bee pollen. PMID:26454344

  1. Soxhlet-assisted matrix solid phase dispersion to extract flavonoids from rape (Brassica campestris) bee pollen.

    Science.gov (United States)

    Ma, Shuangqin; Tu, Xijuan; Dong, Jiangtao; Long, Peng; Yang, Wenchao; Miao, Xiaoqing; Chen, Wenbin; Wu, Zhenhong

    2015-11-15

    Soxhlet-assisted matrix solid phase dispersion (SA-MSPD) method was developed to extract flavonoids from rape (Brassica campestris) bee pollen. Extraction parameters including the extraction solvent, the extraction time, and the solid support conditions were investigated and optimized. The best extraction yields were obtained using ethanol as the extraction solvent, silica gel as the solid support with 1:2 samples to solid support ratio, and the extraction time of one hour. Comparing with the conventional solvent extraction and Soxhlet method, our results show that SA-MSPD method is a more effective technique with clean-up ability. In the test of six different samples of rape bee pollen, the extracted content of flavonoids was close to 10mg/g. The present work provided a simple and effective method for extracting flavonoids from rape bee pollen, and it could be applied in the studies of other kinds of bee pollen.

  2. Enzyme assisted extraction of polysaccharides from the fruit of Cornus officinalis.

    Science.gov (United States)

    You, Qinghong; Yin, Xiulian; Zhao, Yuping

    2013-10-15

    Process of enzyme assisted extraction (EAE) of polysaccharides from Cornus officinalis was optimized by response surface methodology (RSM). The influence of four different factors on the yield of C. officinalis polysaccharides (COP) was studied. Results showed that the optimal conditions were compound enzyme amount of 2.15%, extraction pH of 4.2, extraction temperature of 55 °C and extraction time of 97 min. Under these conditions, the COP yield was 9.29±0.31%, which was well in agreement with the value predicted by the model. The three methods, EAE, hot water extraction (HWE), ultrasound-assisted extraction (UAE) for extracting COP by RSM were further compared. Results showed that EAE had the largest yield of polysaccharides with lower equipment cost.

  3. Ultrasound-Assisted Extraction of Total Phenolic Compounds from Inula helenium

    Directory of Open Access Journals (Sweden)

    Jin Wang

    2013-01-01

    Full Text Available Ultrasound-assisted extraction (UAE of phenolic compounds from Inula helenium was studied. Effects of ethanol concentration, ultrasonic time, solid-liquid ratio, and number of extractions were investigated. An orthogonal array was constructed to optimize UAE process. The optimized extraction conditions were as follows: ethanol concentration, 30%; solid-liquid ratio, 1 : 20; number of extractions, 2 times; extraction time, 30 min. Under the optimal conditions, the yield of total phenolic compounds and chlorogenic acid was 6.13±0.58 and 1.32±0.17 mg/g, respectively. The results showed that high amounts of phenolic compounds can be extracted from I. helenium by ultrasound-assisted extraction technology.

  4. Sequential cloud point extraction for the speciation of mercury in seafood by inductively coupled plasma optical emission spectrometry

    International Nuclear Information System (INIS)

    A novel nonchromatographic speciation technique for the speciation of mercury by sequential cloud point extraction (CPE) combined with inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The method based on Hg2+ was complexed with I- to form HgI42-, and the HgI42- reacted with the methyl green (MG) cation to form hydrophobic ion-associated complex, and the ion-associated complex was then extracted into the surfactant-rich phase of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), which are subsequently separated from methylmercury (MeHg+) in the initial solution by centrifugation. The surfactant-rich phase containing Hg(II) was diluted with 0.5 mol L-1 HNO3 for ICP-OES determination. The supernatant is also subjected to the similar CPE procedure for the preconcentration of MeHg+ by the addition of a chelating agent, ammonium pyrrolidine dithiocarbamate (APDC), in order to form water-insolvable complex with MeHg+. The MeHg+ in the micelles was directly analyzed after disposal as describe above. Under the optimized conditions, the extraction efficiency was 93.5% for Hg(II) and 51.5% for MeHg+ with the enrichment factor of 18.7 for Hg(II) and 10.3 for MeHg+, respectively. The limits of detection (LODs) were 56.3 ng L-1 for Hg(II) and 94.6 ng L-1 for MeHg+ (as Hg) with the relative standard deviations (RSDs) of 3.6% for Hg(II) and 4.5% for MeHg+ (C = 10 μg L-1, n = 7), respectively. The developed technique was applied to the speciation of mercury in real seafood samples and the recoveries for spiked samples were found to be in the range of 93.2-108.7%. For validation, a certified reference material of DORM-2 (dogfish muscle) was analyzed and the determined values are in good agreement with the certified values

  5. Sequential cloud point extraction for the speciation of mercury in seafood by inductively coupled plasma optical emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Li Yingjie [Department of Chemistry, Wuhan University, Wuhan 430072 (China); Hu Bin [Department of Chemistry, Wuhan University, Wuhan 430072 (China)], E-mail: binhu@whu.edu.cn

    2007-10-15

    A novel nonchromatographic speciation technique for the speciation of mercury by sequential cloud point extraction (CPE) combined with inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The method based on Hg{sup 2+} was complexed with I{sup -} to form HgI{sub 4}{sup 2-}, and the HgI{sub 4}{sup 2-} reacted with the methyl green (MG) cation to form hydrophobic ion-associated complex, and the ion-associated complex was then extracted into the surfactant-rich phase of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), which are subsequently separated from methylmercury (MeHg{sup +}) in the initial solution by centrifugation. The surfactant-rich phase containing Hg(II) was diluted with 0.5 mol L{sup -1} HNO{sub 3} for ICP-OES determination. The supernatant is also subjected to the similar CPE procedure for the preconcentration of MeHg{sup +} by the addition of a chelating agent, ammonium pyrrolidine dithiocarbamate (APDC), in order to form water-insolvable complex with MeHg{sup +}. The MeHg{sup +} in the micelles was directly analyzed after disposal as describe above. Under the optimized conditions, the extraction efficiency was 93.5% for Hg(II) and 51.5% for MeHg{sup +} with the enrichment factor of 18.7 for Hg(II) and 10.3 for MeHg{sup +}, respectively. The limits of detection (LODs) were 56.3 ng L{sup -1} for Hg(II) and 94.6 ng L{sup -1} for MeHg{sup +} (as Hg) with the relative standard deviations (RSDs) of 3.6% for Hg(II) and 4.5% for MeHg{sup +} (C = 10 {mu}g L{sup -1}, n = 7), respectively. The developed technique was applied to the speciation of mercury in real seafood samples and the recoveries for spiked samples were found to be in the range of 93.2-108.7%. For validation, a certified reference material of DORM-2 (dogfish muscle) was analyzed and the determined values are in good agreement with the certified values.

  6. Sequential cloud point extraction for the speciation of mercury in seafood by inductively coupled plasma optical emission spectrometry

    Science.gov (United States)

    Li, Yingjie; Hu, Bin

    2007-10-01

    A novel nonchromatographic speciation technique for the speciation of mercury by sequential cloud point extraction (CPE) combined with inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The method based on Hg 2+ was complexed with I - to form HgI 42-, and the HgI 42- reacted with the methyl green (MG) cation to form hydrophobic ion-associated complex, and the ion-associated complex was then extracted into the surfactant-rich phase of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114), which are subsequently separated from methylmercury (MeHg +) in the initial solution by centrifugation. The surfactant-rich phase containing Hg(II) was diluted with 0.5 mol L - 1 HNO 3 for ICP-OES determination. The supernatant is also subjected to the similar CPE procedure for the preconcentration of MeHg + by the addition of a chelating agent, ammonium pyrrolidine dithiocarbamate (APDC), in order to form water-insolvable complex with MeHg +. The MeHg + in the micelles was directly analyzed after disposal as describe above. Under the optimized conditions, the extraction efficiency was 93.5% for Hg(II) and 51.5% for MeHg + with the enrichment factor of 18.7 for Hg(II) and 10.3 for MeHg +, respectively. The limits of detection (LODs) were 56.3 ng L - 1 for Hg(II) and 94.6 ng L - 1 for MeHg + (as Hg) with the relative standard deviations (RSDs) of 3.6% for Hg(II) and 4.5% for MeHg + ( C = 10 μg L -1, n = 7), respectively. The developed technique was applied to the speciation of mercury in real seafood samples and the recoveries for spiked samples were found to be in the range of 93.2-108.7%. For validation, a certified reference material of DORM-2 (dogfish muscle) was analyzed and the determined values are in good agreement with the certified values.

  7. Electrothermal atomic absorption spectrometric determination of vanadium in extracts of soil and sewage sludge certified reference materials after fractionation by means of the Communities Bureau of Reference modified sequential extraction procedure

    International Nuclear Information System (INIS)

    A modified three-step sequential extraction procedure proposed by the Commission of European Communities Bureau of Reference (BCR) was applied to certified reference materials of three different soil groups (rendzina, luvisol, cambisol) and sewage sludge of different composition originating from a municipal water treatment plant in order to assess potential mobility and the distribution of vanadium in the resulting fractions. Analysis of the extracts was carried out by electrothermal atomic absorption spectrometry with Zeeman background correction using transversely heated graphite atomizers. Extracts showed significant matrix interferences which were overcome by the standard addition technique. The original soil and sludge certified reference materials (CRMs) and the extraction residue from the sequential extraction were decomposed by a mixture of HNO3-HClO4-HF in an open system. The content of V determined after decomposition of the samples was in very good agreement with the certified total values. The accuracy of the sequential extraction procedure was checked by comparing the sum of the vanadium contents in the three fractions and in the extraction residue with the certified total content of V. The amounts of vanadium leached were in good correlation with the certified total contents of V in the CRMs of soils and sewage sludge. In the soils examined, vanadium was present almost entirely in the mineral lattice, while in the sewage sludge samples 9-14% was found in the oxidizable and almost 25% in the reducible fractions. The recovery ranged from 93-106% and the precision (RSD) was below 10%

  8. Extraction and preconcentration of trace levels of cobalt using functionalized magnetic nanoparticles in a sequential injection lab-on-valve system with detection by electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Graphical abstract: An approach to performing extraction and preconcentration employing functionalized magnetic particles for the determination of cobalt in the sequential injection lab-on-valve system using detection by electrothermal atomic absorption spectrometry. Highlights: ► New SPE method for cobalt separation/preconcentration was reported. ► Functionalized magnetic nanoparticles were used as adsorbent. ► Extraction, elution, and detection procedures were performed in the LOV system. ► This automatic extraction technique provided a good platform for metal analysis. - Abstract: A new approach to performing extraction and preconcentration employing functionalized magnetic nanoparticles for the determination of trace metals is presented. Alumina-coated iron oxide nanoparticles were synthesized and used as the solid support. The nanoparticles were functionalized with sodium dodecyl sulfate and used as adsorbents for solid phase extraction of the analyte. Extraction, elution, and detection procedures were performed sequentially in the sequential injection lab-on-valve (SI-LOV) system followed by electrothermal atomic absorption spectrometry (ETAAS). Mixtures of hydrophobic analytes were successfully extracted from solution using the synthesized magnetic adsorbents. The potential use of the established scheme was demonstrated by taking cobalt as a model analyte. Under the optimal conditions, the calibration curve showed an excellent linearity in the concentration range of 0.01–5 μg L−1, and the relative standard deviation was 2.8% at the 0.5 μg L−1 level (n = 11). The limit of detection was 6 ng L−1 with a sampling frequency of 18 h−1. The present method has been successfully applied to cobalt determination in water samples and two certified reference materials.

  9. Optimization of Microwave Assisted Extraction of Andrographolide from Andrographis paniculata and its Comparison with Refluxation Extraction Method

    OpenAIRE

    Manvitha Mohan; Salma Khanam; B G Shivananda

    2013-01-01

    A new method using Microwave assisted extraction technique has been developed for extraction of Andrographolide from Andrographis paniculata. Andrographis paniculata is a well-known plant of Ayurveda which is also known as king of bitters because of different bitter principles present in different parts of the plant and exhibits a wide spectrum of biological activities. The MAE conditions such as irradiation time, temperature and coarseness of powder were optimitized by means of orthogonal ar...

  10. Development of on-line single-drop micro-extraction sequential injection system for electrothermal atomic absorption spectrometric determination of trace metals

    International Nuclear Information System (INIS)

    A novel automatic sequential injection (SI) single-drop micro-extraction (SDME) system is proposed as versatile approach for on-line metal preconcentration and/or separation. Coupled to electrothermal atomic absorption spectrometry (ETAAS) the potentials of this SI scheme are demonstrated for trace cadmium determination in water samples. A non-charged complex of cadmium with ammonium diethyldithiophosphate (DDPA) was produced and extracted on-line into a 60 μL micro-drop of di-isobutyl ketone (DIBK). The extraction procedure was performed into a newly designed flow-through extraction cell coupled on a sequential injection manifold. As the complex Cd(II)-DDPA flowed continuously around the micro-droplet, the analyte was extracting into the solvent micro-drop. All the critical parameters were optimized and offered good performance characteristics and high preconcentration ratios. For 600 s micro-extraction time, the enhancement factor was 10 and the sampling frequency was 6 h-1. The detection limit was 0.01 μg L-1 and the precision (RSD at 0.1 μg L-1 of cadmium) was 3.9%. The proposed method was evaluated by analyzing certified reference material

  11. Sequential separation and substoichiometric extraction of cobalt(II), copper(II) and zinc(II) using organic reagents (Preprint No. CT-52)

    International Nuclear Information System (INIS)

    A rapid, selective and simple method has been developed for the sequential separation and substoichiometric extraction of cobalt(II), copper(II) and zinc(II) using organic reagents (isonitrosobenzoylacetone and 1,2,3-benzotriazole) under different experimental conditions. 60Co, 64Cu and 65Zn were used as tracers. The reliability of the separation was checked by γ-ray spectrometry. (author)

  12. Methods of Determining Lead Speciation in Fly Ash by X-ray Absorption Fine-Structure Spectroscopy and a Sequential Extraction Procedure

    OpenAIRE

    Funatsuki, Atsushi; Takaoka, Masaki; Oshita, Kazuyuki; Takeda, Nobuo

    2012-01-01

    Understanding the chemical state of lead in fly ash generated from a waste thermal treatment is important, since the toxicity and solubility of the element depends on its chemical state. This study identified three potential methods for obtaining quantitative information regarding the chemical state of lead in fly ash: X-ray absorption near edge structure (XANES) analysis, extended X-ray absorption fine structure (EXAFS) analysis, and the sequential extraction procedure. The result of this pr...

  13. Characterization of phosphorus species in sediments from the Arabian Sea oxygen minimum zone: Combining sequential extractions and X-ray spectroscopy

    OpenAIRE

    Kraal, Peter; Bostick, Benjamin C.; Behrends, Thilo; Reichart, Gert-Jan; Slomp, Caroline P.

    2015-01-01

    The bulk phosphorus (P) distribution in sediment samples from the oxygen minimum zone of the northern Arabian Sea was determined using two methods: sequential chemical extraction (the ‘SEDEX’ procedure) and X-ray absorption near-edge structure (XANES) spectroscopy of the phosphorus K-edge. Our results show good agreement between iron (Fe-)associated P and calcium phosphate minerals (Ca-P) determined by both methods. Furthermore, we find that SEDEX exchangeable P likely represents loosely Fe-b...

  14. Determination, speciation and distribution of mercury in soil in the surroundings of a former chlor-alkali plant: assessment of sequential extraction procedure and analytical technique

    OpenAIRE

    Frentiu, Tiberiu; Pintican, Bogdan Petru; Butaciu, Sanziana; Mihaltan, Alin Ironim; Ponta, Michaela; Frentiu, Maria

    2013-01-01

    Background The paper presents the evaluation of soil contamination with total, water-available, mobile, semi-mobile and non-mobile Hg fractions in the surroundings of a former chlor-alkali plant in connection with several chemical soil characteristics. Principal Component Analysis and Cluster Analysis were used to evaluate the chemical composition variability of soil and factors influencing the fate of Hg in such areas. The sequential extraction EPA 3200-Method and the determination technique...

  15. Fractionation of metals in street sediment samples by using the BCR sequential extraction procedure and multivariate statistical elucidation of the data

    International Nuclear Information System (INIS)

    The concentrations of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in street sediment samples were determined by flame atomic absorption spectrometry (FAAS) using the modified BCR (the European Community Bureau of Reference) sequential extraction procedure. According to the BCR protocol for extracting the metals from the relevant target phases, 1.0 g of specimen of the sample was treated with 0.11 M acetic acid (exchangeable and bound to carbonates), 0.5 M hydroxylamine hydrochloride (bound to iron- and manganese-oxides), and 8.8 M hydrogen peroxide plus 1 M ammonium acetate (bound to sulphides and organics), sequentially. The residue was treated with aqua regia solution for recovery studies, although this step is not part of the BCR procedure. The mobility sequence based on the sum of the BCR sequential extraction stages was: Cd ∼ Zn (∼90%) > Pb (∼84%) > Cu (∼75%) > Mn (∼70%) > Co (∼57%) > Ni (∼43%) > Cr (∼40%) > Fe (∼17%). Enrichment factors as the criteria for examining the impact of the anthropogenic emission sources of heavy metals were calculated, and it was observed that the highest enriched elements were Cd, Pb, and Zn in the dust samples, average 190, 111, and 20, respectively. Correlation analysis (CA) and principal component analysis (PCA) were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of metals. PCA revealed that the sampling area was mainly influenced from three pollution sources, namely; traffic, industrial, and natural sources. The results show that chemical sequential extraction is a precious operational tool. Validation of the analytical results was checked by both recovery studies and analysis of the standard reference material (NIST SRM 2711 Montana Soil)

  16. Assessment of the influence of traffic-related particles in urban dust using sequential selective extraction and oral bioaccessibility tests.

    Science.gov (United States)

    Patinha, C; Durães, N; Sousa, P; Dias, A C; Reis, A P; Noack, Y; Ferreira da Silva, E

    2015-08-01

    Urban dust is a heterogeneous mix, where traffic-related particles can combine with soil mineral compounds, forming a unique and site-specific material. These traffic-related particles are usually enriched in potentially harmful elements, enhancing the health risk for population by inhalation or ingestion. Urban dust samples from Estarreja city and traffic-related particles (brake dust and white traffic paint) were studied to understand the relative contribution of the traffic particles in the geochemical behaviour of urban dust and to evaluate the long-term impacts of the metals on an urban environment, as well as the risk to the populations. It was possible to distinguish two groups of urban dust samples according to Cu behaviour: (1) one group with low amounts of fine particles (car brands (with more than 10 years old), composed by coarser wear particles; and (2) another group with greater amounts of fine particles (car brands (with less than 10 years old). The results obtained showed that there is no direct correlation between the geoavailability of metals estimated by sequential selective chemical extraction (SSCE) and the in vitro oral bioaccessibility (UBM) test. Thus, oral bioaccessibility of urban dust is site specific. Geoavailability was greatly dependent on particle size, where the bioaccessibility tended to increase with a reduction in particle diameter. As anthropogenic particles showed high metal concentration and a smaller size than mineral particles, urban dusts are of major concern to the populations' health, since fine particles are easily re-suspended, easily ingested, and show high metal bioaccessibility. In addition, Estarreja is a coastal city often influenced by winds, which favours the re-suspension of small-sized contaminated particles. Even if the risk to the population does not represent an acute case, it should not be overlooked, and this study can serve as baseline study for cities under high traffic influence.

  17. Cellulase-assisted extraction of oligosaccharides from defatted rice bran.

    Science.gov (United States)

    Patindol, J; Wang, L; Wang, Y-J

    2007-11-01

    Defatted rice bran was subjected to cellulase treatment in order to increase its extractable oligosaccharides. Various combinations of enzyme concentration (0%, 0.5%, 1.0%, and 2.0%), temperature (room, 30, 40, and 50 degrees C), and time (1, 3, 5, and 16 h) were tested to identify the optimum extraction conditions. The saccharide content and composition of the extracts were analyzed by high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Digestibility was assayed in vitro with human salivary and porcine pancreatic alpha-amylases. Extraction yield ranged from 13.4% (without cellulase) to 39.9% (with 2% cellulase). Total carbohydrates, reducing sugars, and crude protein of the dried extracts ranged from 69.2% to 87.2%, 18.7% to 62.3%, and 7.1% to 22.3%, respectively. Mono- and disaccharides constituted more than 50% of the total carbohydrates in the extracts. Inherent oligosaccharides and those produced by cellulolysis made up less than 25%. The in vitro digestibility of the extracts by alpha-amylases was lower compared with that of the original rice bran sample and potato dextrin, which could be attributed to the increased concentrations of oligosaccharides and reducing sugars. PMID:18034713

  18. Quantitative Ultrasound-Assisted Extraction for Trace-Metal Determination: An Experiment for Analytical Chemistry

    Science.gov (United States)

    Lavilla, Isela; Costas, Marta; Pena-Pereira, Francisco; Gil, Sandra; Bendicho, Carlos

    2011-01-01

    Ultrasound-assisted extraction (UAE) is introduced to upper-level analytical chemistry students as a simple strategy focused on sample preparation for trace-metal determination in biological tissues. Nickel extraction in seafood samples and quantification by electrothermal atomic absorption spectrometry (ETAAS) are carried out by a team of four…

  19. Stability of Anthocyanins from Red Grape Skins under Pressurized Liquid Extraction and Ultrasound-Assisted Extraction Conditions

    Directory of Open Access Journals (Sweden)

    Ali Liazid

    2014-12-01

    Full Text Available The stability of anthocyanins from grape skins after applying different extraction techniques has been determined. The following compounds, previously extracted from real samples, were assessed: delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, peonidin 3-glucoside, malvidin 3-glucoside, peonidin 3-acetylglucoside, malvidin 3-acetylglucoside, malvidin 3-caffeoylglucoside, petunidin 3-p-coumaroylglucoside and malvidin 3-p-coumaroylglucoside (trans. The techniques used were ultrasound-assisted extraction and pressurized liquid extraction. In ultrasound-assisted extraction, temperatures up to 75 °C can be applied without degradation of the aforementioned compounds. In pressurized liquid extraction the anthocyanins were found to be stable up to 100 °C. The relative stabilities of both the glycosidic and acylated forms were evaluated. Acylated derivatives were more stable than non-acylated forms. The differences between the two groups of compounds became more marked on working at higher temperatures and on using extraction techniques with higher levels of oxygen in the extraction media.

  20. Anti-Inflammatory Activity of Pinus koraiensis Cone Bark Extracts Prepared by Micro-Wave Assisted Extraction

    Science.gov (United States)

    Kang, Sun-Ae; Kim, Dong-Hee; Hong, Shin-Hyub; Park, Hye-Jin; Kim, Na-Hyun; Ahn, Dong-Hyun; An, Bong-Jeun; Kwon, Joong-Ho; Cho, Young-Je

    2016-01-01

    In this study, we compared the anti-inflammatory activity of Pinus koraiensis cone bark extracts prepared by conventional extraction and microwave-assisted extraction (MAE). Water extracts and 50% ethanol extracts prepared using MAE were applied to RAW 264.7 cell at 5, 10, 25, and 50 μg/mL of concentrations, and tested for cytoxicity. The group treated with 50 μg/mL of 50% ethanol extracts showed toxicity. In order to investigate the inhibition of nitric oxide (NO) production in RAW 264.7 cells, extracts of water and ethanol were treated with 5, 10, and 25 μg/mL concentrations. The inhibitory activity of water and 50% ethanol extracts groups were determined as 40% and 60% at 25 μg/mL concentration, respectively. We found concentration dependent decreases on inducible NO synthase. The inhibitory effect against forming inflammatory cytokines, prostaglandin E2, tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, was also superior in the 25 μg/mL treated group than the control group. According to these results, the water extracts and 50% ethanol extracts both inhibited inflammatory mediators by reducing the inflammatory response. Therefore, The MAE extracts of P. koraiensis cone bark can be developed as a functional ingredient with anti-inflammatory activity. PMID:27752500

  1. Use of the modified BCR three-step sequential extraction procedure for the study of trace element dynamics in contaminated soils

    International Nuclear Information System (INIS)

    The modified BCR three-step sequential extraction procedure was used to examine the temporal dynamics of trace elements in soils contaminated by an accidental spill from an opencast mine in south-west Spain. Soils were mainly contaminated with pyritic sludge and acidic wastewater, whereas some soils were affected only by acidic wastewater. The distributions obtained for both some major (Ca, Fe and Mn) and trace elements (As, Cd, Cu, Pb and Zn) in the sludge and soil samples taken at different times after the accident, 1-3 months and 21 months, were compared. Sequential extractions were useful in identifying different sources of contamination, and in obtaining additional information on the solubility of secondary minerals formed by pyrite oxidation. Thus, the effectiveness of the BCR procedure has proved to be a useful tool for predicting short- and long-term mobility of trace elements, even in complex environmental scenarios. - The modified BCR three-step sequential extraction procedure has proved a useful prediction tool for short- and long-term mobility of trace elements in contaminated soils

  2. New Approaches for Effective Microwave Assisted Extraction of Caffeine and Catechins from Green Tea

    Directory of Open Access Journals (Sweden)

    Gönül SERDAR

    2016-01-01

    Full Text Available This study was designed to develop an effective microwave assisted extraction (MAE method for extraction of caffeine and catechins from green tea samples. A series of solvents (water, ethanol:water mixture or citric acid:water mixture were used for extraction of green tea samples (fresh, frozen or dried collected in three collection periods (first, second and third collection periods. Tea samples were extracted using water in a close microwave system under the certain extraction conditions. Extraction was carried out under a controlled 600 W microwave power at 80 oC temperature for 4 min irradiation time. Alternative to water, an ethanol-water mixture (1:1 or a citric acid-water (1:1 mixture was used as extracting solvent under the same conditions. After MAE crude aqueous extract was partitioned first with chloroform to separate caffeine then ethyl acetate for catechins.  Both caffeine and catechin extraction was quite successful with microwave assisted system employing only 4 minutes treatment. The highest caffeine yield was obtained in the second collection period using frozen green tea samples and ethanol-water as extracting solvent. The yield of catechin extracts was between 0.84-3.96% depending on the solvent system used for extraction. Ethanol-water mixture seems to be appropriate for effective extraction in the basis of extract yields. However, HPLC results showed that individual catechin content of each extraction is more important criteria for the evaluation of most effective extraction medium rather than the mass of the extract.  Using citric acid as extracting solvent in MAE seem to be more fruitful providing 100% catechin mixture with the highest EGCG content. 

  3. Application of ionic liquids in the microwave-assisted extraction of pectin from lemon peels.

    Science.gov (United States)

    Guolin, Huang; Jeffrey, Shi; Kai, Zhang; Xiaolan, Huang

    2012-01-01

    Microwave-assisted extraction of pectin from lemon peels by using ionic liquid as alternative solvent was investigated. The extracted pectin was detected by Fourier transform infrared spectra. The extraction conditions were optimized through the different experiments in conjunction with the response surface methodology. A pectin yield of 24.68 % was obtained under the optimal parameters: the extraction temperature of 88°C, the extraction time of 9.6 min, and a liquid-solid ratio of 22.7 ml · g(-1). The structure of the pretreated lemon peel samples and the samples after microwave-assisted extraction were characterized by a field emission scanning electron microscope.

  4. Application of Ionic Liquids in the Microwave-Assisted Extraction of Pectin from Lemon Peels

    Directory of Open Access Journals (Sweden)

    Huang Guolin

    2012-01-01

    Full Text Available Microwave-assisted extraction of pectin from lemon peels by using ionic liquid as alternative solvent was investigated. The extracted pectin was detected by Fourier transform infrared spectra. The extraction conditions were optimized through the different experiments in conjunction with the response surface methodology. A pectin yield of 24.68 % was obtained under the optimal parameters: the extraction temperature of 88°C, the extraction time of 9.6 min, and a liquid-solid ratio of 22.7 ml⋅g-1. The structure of the pretreated lemon peel samples and the samples after microwave-assisted extraction were characterized by a field emission scanning electron microscope.

  5. Ultrasound-assisted extraction of total flavonoids from Aconitum gymnandrum

    Directory of Open Access Journals (Sweden)

    Ling-Li Zheng

    2014-01-01

    Full Text Available Background: Aconitum gymnandrum is a Chinese traditional herb used as carminative and analgesic. In this study, A. gymnandrum was used as an experimental matrix. Materials and Methods: Optimized ultrasonic extraction technology of total flavonoids from the A. gymnandrum Maxim was studied by using the methodology of single factor and orthogonal design to study the effects of operation conditions, such as ethanol content, ultrasonic wave power, temperature, ultrasonic wave radiation time, and the ratio of sample weight to solvent volume. Result: Through the orthogonal experiment, the optimal extraction conditions were determined as follows: Ultrasonic power 100 W, ultrasonic temperature 45°C, 60% ethyl alcohol, extraction time 30 min, and solid-liquid ratio 1:20. Conclusion: Under the optimum parameters, the extraction ratio of total flavonoids from the A. gymnandrum Maxim is about 1.278%.

  6. Microwave-assisted extraction of anthocyanin from Chinese bayberry and its effects on anthocyanin stability

    Directory of Open Access Journals (Sweden)

    Wenkai DUAN

    2015-09-01

    Full Text Available AbstractAnthocyanins are present in high concentrations in Chinese bayberry, Myrica rubra Sieb. & Zucc. Herein, a microwave-assisted extraction was used to extract the anthocyanins from Chinese bayberry. The HPLC chromatogram of the extracts showed that the anthocyanin components were slightly hydrolysed during the extraction process. Further experiments confirmed that microwave irradiation slightly hydrolysed cyanidin-3-O-glucoside to cyanidin, but did not significantly influence the antioxidant activity of the extracts. Optimized extraction conditions for total anthocyanin content were a solid-to-liquid ratio, extraction temperature, and extraction time of 1:50, 80 °C, and 15 min, respectively. Under these conditions, the anthocyanin content was 2.95 ± 0.08 mg·g−1, and the antioxidant activity yield was 279.96 ± 0.1 μmol.·g−1 Trolox equivalent on a dry weight basis. These results indicated that microwave-assisted extraction was a highly efficient extraction method with reduced processing time. However, under some extraction conditions it could damage the anthocyanins. These results provide an important guide for the application of microwave extraction.

  7. Aqueous enzyme assisted oil extraction from oilseeds and emulsion de-emulsifying methods: a review

    OpenAIRE

    Mat Yusoff, Masni; Gordon, Mike; Niranjan, Keshavan

    2014-01-01

    Regulatory, safety, and environmental issues have prompted the development of aqueousenzymatic extraction (AEE) for extracting components from oil-bearing materials. The emulsion resulting from AEE requires de-emulsification to separate the oil; when enzymes are used for this purpose, the method is known as aqueous enzymatic emulsion de-emulsification (AEED). In general, enzyme assisted oil extraction is known to yield oil having highly favourable characteristics. This review covers techno...

  8. Optimization of Ultrasound-Assisted Extraction of Anthocyanins from Mulberry, Using Response Surface Methodology

    OpenAIRE

    Ren-You Gan; Wen-Hua Ling; Tang-Bin Zou; Min Wang

    2011-01-01

    Mulberry is one of the most widely used traditional Chinese medicines. Anthocyanins are the main bioactive components of mulberry, and possess important biological activities, such as antimicrobial, anti-inflammatory and antioxidant activities. This study investigated the ultrasound-assisted extraction (UAE) of anthocyanins from mulberry by using response surface methodology (RSM). The extraction conditions associated with anthocyanin yield, including extraction solvent, liquid-to-solid rate,...

  9. Ultrasound-Assisted Extraction of Antioxidants in Misai Kucing (Orthosiphon stamineus)

    OpenAIRE

    Swee Kheng Ho; Chin Ping Tan; Yin Yin Thoo; Faridah Abas; Chun Wai Ho

    2014-01-01

    Ultrasound-assisted extraction (UAE) with ethanol was used to extract the compounds responsible for the antioxidant activities of Misai Kucing (Orthosiphon stamineus). Response surface methodology (RSM) was used to optimize four independent variables: ethanol concentration (%), amplitude (%), duty cycle (W/s) and extraction time (min). Antioxidant compounds were determined by total phenolic content and total flavonoid content to be 1.4 g gallic acid equivalent/100 g DW and 45 g catechin equiv...

  10. Saffron Samples of Different Origin: An NMR Study of Microwave-Assisted Extracts

    OpenAIRE

    Sobolev, Anatoly P.; Simone Carradori; Donatella Capitani; Silvia Vista; Agata Trella; Federico Marini; Luisa Mannina

    2014-01-01

    An NMR analytical protocol is proposed to characterize saffron samples of different geographical origin (Greece, Spain, Hungary, Turkey and Italy). A microwave-assisted extraction procedure was developed to obtain a comparable recovery of metabolites with respect to the ISO specifications, reducing the solvent volume and the extraction time needed. Metabolite profiles of geographically different saffron extracts were compared showing significant differences in the content of some metabolites.

  11. Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

    OpenAIRE

    Ling-Li Zheng; Guan Wen; Min-Yong Yuan; Feng Gao

    2016-01-01

    Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP) assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM) adopting yield as response, the optimal conditions we...

  12. Microwave-assisted extraction of polysaccharides from Yupingfeng powder and their antioxidant activity

    OpenAIRE

    Dan Wang; Bi-Bo Zhang; Xiao-Xia Qu; Feng Gao; Min-Yong Yuan

    2015-01-01

    Background: Microwave assisted reflux extraction of polysaccharides YPF-P from the famous Chinese traditional drug, Yupingfeng powder, optimization of extracting conditions and evaluation of their antioxidant activity were conducted in this study. Results: Single factor effect trends were achieved through yields and contends of YPF P obtained from different extracting conditions. Then through a three level, four variable Box Behnken design of response surface methodology adopting yield as res...

  13. Sequential extraction method for determination of Fe(II/III) and U(IV/VI) in suspensions of iron-bearing phyllosilicates and uranium.

    Science.gov (United States)

    Luan, Fubo; Burgos, William D

    2012-11-01

    Iron-bearing phyllosilicates strongly influence the redox state and mobility of uranium because of their limited hydraulic conductivity, high specific surface area, and redox reactivity. Standard extraction procedures cannot be accurately applied for the determination of clay-Fe(II/III) and U(IV/VI) in clay mineral-U suspensions such that advanced spectroscopic techniques are required. Instead, we developed and validated a sequential extraction method for determination of clay-Fe(II/III) and U(IV/VI) in clay-U suspensions. In our so-called "H(3)PO(4)-HF-H(2)SO(4) sequential extraction" method, H(3)PO(4)-H(2)SO(4) is used first to solubilize and remove U, and the remaining clay pellet is subject to HF-H(2)SO(4) digestion. Physical separation of U and clay eliminates valence cycling between U(IV/VI) and clay-Fe(II/III) that otherwise occurred in the extraction solutions and caused analytical discrepancies. We further developed an "automated anoxic KPA" method to measure soluble U(VI) and total U (calculate U(IV) by difference) and modified the conventional HF-H(2)SO(4) digestion method to eliminate a series of time-consuming weighing steps. We measured the kinetics of uraninite oxidation by nontronite using this sequential extraction method and anoxic KPA method and measured a stoichiometric ratio of 2.19 ± 0.05 mol clay-Fe(II) produced per mol U(VI) produced (theoretical value of 2.0). We found that we were able to recover 98.0-98.5% of the clay Fe and 98.1-98.5% of the U through the sequential extractions. Compared to the theoretical stoichiometric ratio of 2.0, the parallel extractions of 0.5 M HCl for clay-Fe(II) and 1 M NaHCO(3) for U(VI) leached two-times more Fe(II) than U(VI). The parallel extractions of HF-H(2)SO(4) for clay Fe(II) and 1 M NaHCO(3) for U(VI) leached six-times more Fe(II) than U(VI). PMID:23075386

  14. Determination of As(III) and As(V) in soils using sequential extraction combined with flow injection hydride generation atomic fluorescence detection

    International Nuclear Information System (INIS)

    An analytical procedure for determination of As(III) and As(V) in soils using sequential extraction combined with flow injection (FI) hydride generation atomic fluorescence spectrometry (HG-AFS) was presented. The soils were sequentially extracted by water, 0.6 mol l-1 KH2PO4 solution, 1% (v/v) HCl solution and 1% (w/v) NaOH solution. The arsenite (As(III)) in extract was analyzed by HG-AFS in the medium of 0.1 mol l-1 citric acid solution, then the total arsenic in extract was determined by HG-AFS using on-line reduction of arsenate with L-cysteine. The concentration of arsenate (As(V)) was calculated by the difference. The optimum conditions of extraction and determination were studied in detail. The detection limit (3σ) for As(III) and As(V) were 0.11 and 0.07 μg l-1, respectively. The relative standard deviation (R.S.D.) was 1.43% (n=11) at the 10 μg l-1 As level. The method was applied in the determination of As(III) and As(V) of real soils and the recoveries of As(III) and As(V) were in the range of 89.3-118 and 80.4-111%, respectively

  15. Application of methods (sequential extraction procedures and high-pressure digestion method) to fly ash particles to determine the element constituents: A case study for BCR 176

    International Nuclear Information System (INIS)

    Sequential extraction procedures and the high-pressure digestion method were selected to determine the element constituents of fly ash samples. Sequential extraction is one of the most useful methods used to measure the various elements from municipal solid waste incineration ash and contaminated soils. The extract from each step is analyzed using various techniques and equipments, and the results are then evaluated. In this work, a six-step extraction procedure modified from that of Tessier et al. and Wang et al. was performed and applied to the certified reference material BCR 176 (city waste incineration ash). Analyses were carried out by various techniques such as inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma-mass spectrometry (ICP-MS), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX), and X-ray powder diffraction (XRPD) to evaluate the characteristics of fly ash. The extraction efficiency of many elements was higher than 80%, and the relative standard deviations (RSD) for recovery of most elements were within 10%. In addition, an H2O2 + HNO3 + HF mixed acid digestion solution processed using a low-temperature evaporation procedure was selected as the optimal process for fly ash digestion. The results of this work provide information on the chemical composition, distribution, and potential mobility of the investigated elements

  16. Microwave-Assisted Extraction Followed by Solid-Phase Extraction for the Chromatographic Analysis of Alkaloids in Stephania cepharantha.

    Science.gov (United States)

    Liu, Ying; Xie, Daotao; Kang, Yun; Wang, Yaqin; Yang, Ping; Guo, Jixian; Huang, Jianming

    2016-04-01

    A procedure involving microwave-assisted extraction (MAE) followed by solid-phase extraction (SPE) was established for the extraction and purification of three bisbenzylisoquinoline alkaloids from Stephania cepharantha, and a reversed-phase high-performance liquid chromatography (HPLC) method was developed for the quantification of the target alkaloids. Chromatographic separation was achieved on a Phenomenex Luna Phenyl-Hexyl column. Prior to the HPLC analysis, the alkaloids were rapidly extracted by an optimized MAE process using 0.01 mol/L hydrochloric acid as the solvent. The MAE extract was subsequently purified by SPE using a cation-exchange polymeric cartridge. The MAE-SPE procedure extracted the three alkaloids with satisfactory recoveries ranging from 100.44 to 102.12%. In comparison with the MAE, Soxhlet and ultrasonic-assisted extractions, the proposed MAE-SPE method showed satisfactory cleanup efficiency. Thus, the validated MAE-SPE-HPLC method is specific, accurate and applicable to the determination of alkaloids in S. cepharantha.

  17. Ball mill assisted rapid mechanochemical extraction method for natural products from plants.

    Science.gov (United States)

    Wang, Man; Bi, Wentao; Huang, Xiaohua; Chen, David Da Yong

    2016-06-01

    A ball mill assisted mechanochemical extraction method was developed to extract compounds of natural product (NP) from plant using ionic liquid (IL). A small volume ball mill, also known as PastPrep(®) Homogenizer, which is often used for high-speed lysis of biological samples and for other applications, was used to dramatically increase the speed, completeness and reproducibility of the extraction process at room temperature to preserve the chemical integrity of the extracted compounds. In this study, tanshinones were selected as target compounds to evaluate the performance of this extraction method. Factors affecting the extraction efficiency, such as the duration, IL concentration and solid/liquid ratio were systematically optimized using the response surface methodology. Under the optimized conditions, the described method was more efficient and much faster than the conventional extraction methods such as methanol based ultrasound assisted extraction (UAE) and heat reflux extraction (HRE) that consumes a lot more organic solvent. In addition, the natural products of interest were enriched by anion metathesis of ionic liquids, combining extraction and preconcentration in the same process. The extractant was analyzed by HPLC and LC-MS. The reproducibility (RSD, n=5), correlation coefficient (r(2)) of the calibration curve, and the limit of detection, were determined to be in the range of 4.7-5.2%, 0.9992-0.9995, and 20-51ng/mL, respectively. PMID:27157426

  18. Ionic Liquid-Based Microwave-Assisted Extraction of Flavonoids from Bauhinia championii (Benth. Benth.

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2012-12-01

    Full Text Available An ionic liquids (IL-based microwave-assisted approach for extraction and determination of flavonoids from Bauhinia championii (Benth. Benth. was proposed for the first time. Several ILs with different cations and anions and the microwave-assisted extraction (MAE conditions, including sample particle size, extraction time and liquid-solid ratio, were investigated. Two M 1-butyl-3-methylimidazolium bromide ([bmim] Br solution with 0.80 M HCl was selected as the optimal solvent. Meanwhile the optimized conditions a ratio of liquid to material of 30:1, and the extraction for 10 min at 70 °C. Compared with conventional heat-reflux extraction (CHRE and the regular MAE, IL-MAE exhibited a higher extraction yield and shorter extraction time (from 1.5 h to 10 min. The optimized extraction samples were analysed by LC-MS/MS. IL extracts of Bauhinia championii (Benth.Benth consisted mainly of flavonoids, among which myricetin, quercetin and kaempferol, β-sitosterol, triacontane and hexacontane were identified. The study indicated that IL-MAE was an efficient and rapid method with simple sample preparation. LC-MS/MS was also used to determine the chemical composition of the ethyl acetate/MAE extract of Bauhinia championii (Benth. Benth, and it maybe become a rapid method to determine the composition of new plant extracts.

  19. Comparison of microwave and ultrasound-assisted extraction techniques for leaching of phenolic compounds from nettle.

    Science.gov (United States)

    Ince, Alev Emine; Sahin, Serpil; Sumnu, Gulum

    2014-10-01

    In this study, extraction of phenolic compounds from nettle by microwave and ultrasound was studied. In both microwave and ultrasound-assisted extractions, effects of extraction time (5-20 min for microwave; 5-30 min for ultrasound) and solid to solvent ratio (1:10, 1:20, and 1:30 g/mL) on total phenolic content (TPC) were investigated. Effects of different powers (50 % and 80 %) were also studied for ultrasound-assisted extraction. In microwave-assisted extraction, the optimum TPC of the extracts (24.64 ± 2.36 mg GAE/g dry material) was obtained in 10 min and at 1:30 solid to solvent ratio. For ultrasound-assisted extraction, the condition that gave the highest TPC (23.86 ± 1.92 mg GAE/g dry material) was 30 min, 1:30 solid to solvent ratio, and 80 % power. Extracts obtained at the optimum conditions of microwave and ultrasound were compared in terms of TPC, antioxidant activity (AA) and concentration of phenolic acids with conventional extraction and maceration, respectively. Microwave reduced extraction time by 67 %. AA of extracts varied between 2.95 ± 0.01 and 4.48 ± 0.03 mg DPPH/g dry material among four methods. Major phenolic compounds were determined as naringenin and chlorogenic acid in nettle. PMID:25328225

  20. In Vitro Screening for β-Hydroxy-β-methylglutaryl-CoA Reductase Inhibitory and Antioxidant Activity of Sequentially Extracted Fractions of Ficus palmata Forsk

    Directory of Open Access Journals (Sweden)

    Danish Iqbal

    2014-01-01

    Full Text Available Hypercholesterolemia-induced oxidative stress has been strongly implicated in the pathogenesis of atherosclerosis, which is one of the major causes of mortality worldwide. The current work, for the first time, accounts the antioxidant, genoprotective, antilipoperoxidative, and HMG-CoA reductase (EC 1.1.1.34 inhibitory properties of traditional medicinal plant, Ficus palmata Forsk. Our result showed that among sequentially extracted fractions of Ficus palmata Forsk, FPBA (F. palmata bark aqueous extract and FPLM (F. palmata leaves methanolic extract extracts have higher phenolic content and also exhibited significantly more radical scavenging (DPPH and Superoxide and antioxidant (FRAP capacity. Moreover, FPBA extract also exhibited significantly higher inhibition of lipid peroxidation assay. Additionally, results showed almost complete and partial protection of oxidatively damaged DNA by these plant extracts when compared to mannitol. Furthermore, our results showed that FPBA extract (IC50=9.1±0.61 µg/mL exhibited noteworthy inhibition of HMG-CoA reductase activity as compared to other extracts, which might suggest its role as cardioprotective agent. In conclusion, results showed that FPBA extract not only possess significant antioxidant and genoprotective property but also is able to attenuate the enzymatic activity of HMG-CoA reductase, which might suggest its role in combating various oxidative stress-related diseases, including atherosclerosis.

  1. Presumptive diagnosis of subclinical infections utilizing computer-assisted analysis of sequential enzyme-linked immunosorbent assays against multiple antigens.

    Science.gov (United States)

    Mallinson, E T; Snyder, D B; Marquardt, W W; Russek-Cohen, E; Savage, P K; Allen, D C; Yancey, F S

    1985-09-01

    One-hundred-seventy-two serum samples, collected sequentially from four flocks of egg- and meat-type chickens, were evaluated for antibodies to multiple infectious agents by enzyme-linked immunosorbent assay (MELISA). The MELISA system used provided simultaneous measurement of antibody titers against avian infectious bronchitis (IB), infectious bursal disease (BD), Newcastle disease, avian encephalomyelitis and reovirus infections, and Mycoplasma gallisepticum. The use of computer-generated graphic print outs of relative MELISA titers provided immediate visulization of over 740 data points and convenient detection of any temporal changes in median titer class (MTC). The temporally changing MTC, or flock profiles obtained, indicated that negligible or waning IB immunity may be a common occurrence in previously vaccinated commercial chickens. These profiles further suggested that, despite no IB revaccination, these same flocks experienced episodes of reexposure to IB which otherwise may have been difficult to detect by conventional clinical or diagnostic laboratory protocols. MELISA profiles and sequential histologic examinations of bursas of Fabricius also provided evidence of a possible BD vaccination problem in young chickens that also experienced excessive losses from coccidiosis, ulcerative enteritis, and Marek's disease. Short sampling intervals were found to foster the detection and definition of fluctuations in MTC which otherwise may have been missed. PMID:4048057

  2. Optimization of microwave-assisted extraction of polysaccharide from Psidium guajava L. fruits.

    Science.gov (United States)

    Amutha Gnana Arasi, Michael Antony Samy; Gopal Rao, Manchineela; Bagyalakshmi, Janardanan

    2016-10-01

    This study deals with the optimization of microwave assisted extraction of polysaccharide from Psidium guajava L. fruit using Response surface methodology. To evaluate the effect of three independent variables, Water to plant material ratio, microwave power used for extraction and Irradiation time, central composite design has been employed. The yield is considered as dependent variable. The design model estimated the optimum yield of 6.81677% at 200W microwave power level, 3:1 water to plant material ratio and 20min of irradiation time. Three factors three levels Central composite design coupled with RSM was used to model the extraction process. ANOVA was performed to find the significance of the model. The polysaccharide extracted using microwave assisted extraction process was analyzed using FTIR Spectroscopy. PMID:27180292

  3. Membrane contactor assisted water extraction system for separating hydrogen peroxide from a working solution, and method thereof

    Science.gov (United States)

    Snyder, Seth W.; Lin, Yupo J.; Hestekin' Jamie A.; Henry, Michael P.; Pujado, Peter; Oroskar, Anil; Kulprathipanja, Santi; Randhava, Sarabjit

    2010-09-21

    The present invention relates to a membrane contactor assisted extraction system and method for extracting a single phase species from multi-phase working solutions. More specifically one preferred embodiment of the invention relates to a method and system for membrane contactor assisted water (MCAWE) extraction of hydrogen peroxide (H.sub.2O.sub.2) from a working solution.

  4. Box-Behnken design for investigation of microwave-assisted extraction of patchouli oil

    Science.gov (United States)

    Kusuma, Heri Septya; Mahfud, Mahfud

    2015-12-01

    Microwave-assisted extraction (MAE) technique was employed to extract the essential oil from patchouli (Pogostemon cablin). The optimal conditions for microwave-assisted extraction of patchouli oil were determined by response surface methodology. A Box-Behnken design (BBD) was applied to evaluate the effects of three independent variables (microwave power (A: 400-800 W), plant material to solvent ratio (B: 0.10-0.20 g mL-1) and extraction time (C: 20-60 min)) on the extraction yield of patchouli oil. The correlation analysis of the mathematical-regression model indicated that quadratic polynomial model could be employed to optimize the microwave extraction of patchouli oil. The optimal extraction conditions of patchouli oil was microwave power 634.024 W, plant material to solvent ratio 0.147648 g ml-1 and extraction time 51.6174 min. The maximum patchouli oil yield was 2.80516% under these optimal conditions. Under the extraction condition, the experimental values agreed with the predicted results by analysis of variance. It indicated high fitness of the model used and the success of response surface methodology for optimizing and reflect the expected extraction condition.

  5. Kinetics of ultrasound-assisted extraction of antioxidant polyphenols from food by-products: Extraction and energy consumption optimization.

    Science.gov (United States)

    Pradal, Delphine; Vauchel, Peggy; Decossin, Stéphane; Dhulster, Pascal; Dimitrov, Krasimir

    2016-09-01

    Ultrasound-assisted extraction (UAE) of antioxidant polyphenols from chicory grounds was studied in order to propose a suitable valorization of this food industry by-product. The main parameters influencing the extraction process were identified. A new mathematical model for multi-criteria optimization of UAE was proposed. This kinetic model permitted the following and the prediction of the yield of extracted polyphenols, the antioxidant activity of the obtained extracts and the energy consumption during the extraction process in wide ranges of temperature (20-60°C), ethanol content in the solvent (0-60% (vol.) in ethanol-water mixtures) and ultrasound power (0-100W). After experimental validation of the model, several simulations at different technological restrictions were performed to illustrate the potentiality of the model to find the optimal conditions for obtaining a given yield within minimal process duration or with minimal energy consumption. The advantage of ultrasound assistance was clearly demonstrated both for the reduction of extraction duration and for the reduction of energy consumption. PMID:27150754

  6. Optimized Ultrasonic-assisted Extraction of Flavonoids from Pyracantha fortuneana Fruit and Evaluation of Antibacterial Activities

    Directory of Open Access Journals (Sweden)

    Yun Zhang

    2014-12-01

    Full Text Available Ultrasonic-Assisted Extraction (UAE method was developed for extraction of total flavonoids from Pyracantha fortuneana fruit. The UAE parameters and the antioxidant activities of flavonoids extract were investigated. Important variables and their levels were obtained using single factor analysis method and central composite design. Through Response Surface Methodology (RSM design experiments, the processing conditions were optimized as follows: ethanol concentration, 81.15%; liquid-solid ratio, 30.00 mL/g; extraction time, 3.14 h; and temperature, 69.55°C. Under the optimum condition, the extraction yield was 1.261%, which was well matched with the predicted values of 1.263%. The antibacterial activities of extract against four bacterial strains were determined by agar well diffusion method and the results indicated that the extract showed potent antibacterial activities, which concludes its application as natural antibacterial agent.

  7. Microwave assisted-semi bionic extraction of lignan compounds from Fructus Forsythiae by orthogonal design

    Institute of Scientific and Technical Information of China (English)

    TU Qiu-yun; ZHOU Chun-shan; TANG Jian-ping

    2008-01-01

    Microwave assisted-semi bionic extraction (MASBE) process for lignans from Fructus Forsythiae was studied. The influences of solvent pH value, microwave power, dosage of solvent and irradiation time were investigated. Optimum extracting parameters were determined by orthogonal experiments as follows: pH value of solvent at first extraction is 5.5-6.0, that at the second extraction is 7-8; microwave power is 700 W; mass ratio of Fructus Forsythiae to water is 1:12; irradiation time is 10 min, and extracting times is two. Under these optimal conditions, the yield of lignans reaches 0.364%. Compared with the conventionalextraction methods, the MASBE process has the advantages of high extraction rate, high extraction selectivity.

  8. Ultrasonic-assisted extraction of phenolic and antioxidative compounds from lizard tail (Houttuynia cordata Thunb.

    Directory of Open Access Journals (Sweden)

    Trakul Prommajak

    2014-02-01

    Full Text Available Lizard tail (Houttuynia cordata Thunb. is an Asian herb which has many biological activities, including antioxidative property from polyphenolic compounds. Response surface methodology and Box-Behnken design were employed to study the effect of extraction temperature (30 to 70°C, extraction time (10 to 30 min, ethanol concentration (30 to 70%, and solvent to sample ratio (2 to 6 ml/g on ultrasonic-assisted extraction of phenolic compounds from lizard tail and antioxidant capacity of the herb extract. Extraction temperature was the most relevant factor on the responses. Optimal condition was the extraction temperature of 70°C for 30 min, using 60% ethanol concentration at the solvent to sample ratio of 5 ml/g. Model adequacies were confirmed by extraction at the optimal condition and normality of standardized residuals.

  9. Process optimization and analysis of microwave assisted extraction of pectin from dragon fruit peel.

    Science.gov (United States)

    Thirugnanasambandham, K; Sivakumar, V; Prakash Maran, J

    2014-11-01

    Microwave assisted extraction (MAE) technique was employed for the extraction of pectin from dragon fruit peel. The extracting parameters were optimized by using four-variable-three-level Box-Behnken design (BBD) coupled with response surface methodology (RSM). RSM analysis indicated good correspondence between experimental and predicted values. 3D response surface plots were used to study the interactive effects of process variables on extraction of pectin. The optimum extraction conditions for the maximum yield of pectin were power of 400 W, temperature of 45 °C, extracting time of 20 min and solid-liquid ratio of 24 g/mL. Under these conditions, 7.5% of pectin was extracted.

  10. Towards the industrial production of medicinal tincture by ultrasound assisted extraction.

    Science.gov (United States)

    Valachovic, P; Pechova, A; Mason, T J

    2001-04-01

    Experiments related to the industrial production of medicinal tinctures of sage (Salvia officinalis L.) and valerian (Valeriana officinalis L.) were performed using ultrasonically assisted extraction and quality of the final tincture was evaluated by gas chromatography and dry residue determination. The constituents of the active sage compound: borneol, cineole, alpha- and beta-thujone and also the dry residue were measured. In the case of valerian extractions, the efficiency of sonicated extraction was compared with classical extraction. The course of only the dry residue was monitored. The influence of ultrasound on the quality of valerian tincture was examined by HPLC. PMID:11326604

  11. Ultrasound-assisted extraction of total flavonoids from Aconitum gymnandrum

    OpenAIRE

    Ling-Li Zheng; Dan Wang; Yuan-Yuan Li; Hong-Yan Peng; Ming-Yong Yuan; Feng Gao

    2014-01-01

    Background: Aconitum gymnandrum is a Chinese traditional herb used as carminative and analgesic. In this study, A. gymnandrum was used as an experimental matrix. Materials and Methods: Optimized ultrasonic extraction technology of total flavonoids from the A. gymnandrum Maxim was studied by using the methodology of single factor and orthogonal design to study the effects of operation conditions, such as ethanol content, ultrasonic wave power, temperature, ultrasonic wave radiation time, and t...

  12. Response Surface Methodology for Ultrasound-Assisted Extraction of Astaxanthin from Haematococcus pluvialis

    Directory of Open Access Journals (Sweden)

    Hong-Fu Wu

    2013-05-01

    Full Text Available Astaxanthin is a novel carotenoid nutraceutical occurring in many crustaceans and red yeasts. It has exhibited various biological activities including prevention or amelioration of cardiovascular disease, gastric ulcer, hypertension, and diabetic nephropathy. In this study, ultrasound-assisted extraction was developed for the effective extraction of astaxanthin from Haematococcus pluvialis. Some parameters such as extraction solvent, liquid-to-solid ratio, extraction temperature, and extraction time were optimized by single-factor experiment and response surface methodology. The optimal extraction conditions were 48.0% ethanol in ethyl acetate, the liquid-to-solid ratio was 20:1 (mL/g, and extraction for 16.0 min at 41.1 °C under ultrasound irradiation of 200 W. Under optimal conditions, the yield of astaxanthin was 27.58 ± 0.40 mg/g. The results obtained are beneficial for the full utilization of Haematococcus pluvialis, which also indicated that ultrasound-assisted extraction is a very useful method for extracting astaxanthin from marine life.

  13. Optimization of Ultrasound Assisted Extraction of Functional Ingredients from Stevia Rebaudiana Bertoni Leaves

    Science.gov (United States)

    Šic Žlabur, Jana; Voća, Sandra; Dobričević, Nadica; Brnčić, Mladen; Dujmić, Filip; Rimac Brnčić, Suzana

    2015-04-01

    The aim of the present study was to reveal an effective extraction procedure for maximization of the yield of steviol glycosides and total phenolic compounds as well as antioxidant activity in stevia extracts. Ultrasound assisted extraction was compared with conventional solvent extraction. The examined solvents were water (100°C/24 h) and 70% ethanol (at 70°C for 30 min). Qualitative and quantitative analyses of steviol glycosides in the extracts obtained were performed using high performance liquid chromatography. Total phenolic compounds, flavonoids, and radical scavenging capacity by 2, 2-azino-di-3-ethylbenzothialozine- sulphonic acid) assay were also determined. The highest content of steviol glycosides, total phenolic compounds, and flavonoids in stevia extracts were obtained when ultrasound assisted extraction was used. The antioxidant activity of the extracts was correlated with the total amount of phenolic compounds. The results indicated that the examined sonication parameters represented as the probe diameter (7 and 22 mm) and treatment time (2, 4, 6, 8, and 10 min) significantly contributed to the yield of steviol glycosides, total phenolic compounds, and flavonoids. The optimum conditions for the maximum yield of steviol glycosides, total phenolic compounds, and flavonoids were as follows: extraction time 10 min, probe diameter 22 mm, and temperature 81.2°C.

  14. Microwave-Assisted Extraction of Oleanolic Acid and Ursolic Acid from Ligustrum lucidum Ait

    Directory of Open Access Journals (Sweden)

    Yang Song

    2011-08-01

    Full Text Available Oleanolic acid and ursolic acid are the main active components in fruit of Ligustrum lucidum Ait, and possess anticancer, antimutagenic, anti-inflammatory, antioxidative and antiprotozoal activities. In this study, microwave-assisted extraction of oleanolic acid and ursolic acid from Ligustrum lucidum was investigated with HPLC-photodiode array detection. Effects of several experimental parameters, such as type and concentration of extraction solvent, ratio of liquid to material, microwave power, extraction temperature and microwave time, on the extraction efficiencies of oleanolic acid and ursolic acid from Ligustrum lucidum were evaluated. The influence of experimental parameters on the extraction efficiency of ursolic acid was more significant than that of oleanolic acid (p < 0.05. The optimal extraction conditions were 80% ethanol aqueous solution, the ratio of material to liquid was 1:15, and extraction for 30 min at 70 °C under microwave irradiation of 500 W. Under optimal conditions, the yields of oleanolic acid and ursolic acid were 4.4 ± 0.20 mg/g and 5.8 ± 0.15 mg/g, respectively. The results obtained are helpful for the full utilization of Ligustrum lucidum, which also indicated that microwave-assisted extraction is a very useful method for extraction of oleanolic acid and ursolic acid from plant materials.

  15. Removal of VOCs from groundwater using membrane-assisted solvent extraction

    International Nuclear Information System (INIS)

    A membrane-assisted solvent extraction (MASX) system coupled to a membrane-assisted distillation stripping (MADS) system for use in decontaminating groundwater is discussed. Volatile organic compounds (VOCs) are extracted in the MASX using a sunflower oil solvent. In the MADS, VOCs are stripped from the sunflower oil, and the oil is recycled to the MASX. Thermodynamic data for the sunflower oil-water-VOCs system were experimentally collected. Published membrane-mass transfer results along with these data were used to design the MASX and MADS modules

  16. Effect of onion extract on corneal haze suppression after air assisted lamellar keratectomy

    OpenAIRE

    Kim, Soohyun; Park, Young Woo; LEE, Euiri; PARK, Sang Wan; Park, Sungwon; Noh, Hyunwoo; Kim, Jong Whi; Seong, Je Kyung; SEO, Kangmoon

    2015-01-01

    This study evaluated the effect of onion extract on corneal haze suppression after applying the air assisted lamellar keratectomy. The air assisted lamellar keratectomy was performed on 24 canine eyes. They were treated with an artificial tear (group C), prednisolone acetate (group P), onion extract (group O) and TGF-β1 (group T) three times per day from 7 to 28 days after the surgery. Corneal haze occurred on the all eyes and was observed beginning 7 days after the surgery. The haze was sign...

  17. Mediator-assisted photocurrent extraction from the thylakoids

    International Nuclear Information System (INIS)

    Photocurrent extracted from the thylakoids has been studied as a function of electron mediator concentration. Phenazine methosulfate is used to facilitate the charge transfer from the thylakoid's charge transport chain to the outside medium. The photocurrent has been shown to originate from the photosynthesis on the thylakoid membranes. Comparing with a previous study using para-Benzoquinone as the mediator, a similar peak effect in the photocurrent as a function of concentration is observed, but the magnitude of the current is nearly a thousand times greater. A semi-quantitative analysis is presented to explain the data found in those systems

  18. Time saving modified BCR sequential extraction procedure for the fraction of Cd, Cr, Cu, Ni, Pb and Zn in sediment samples of polluted lake

    International Nuclear Information System (INIS)

    The mobility, availability and persistence of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in contaminated lake sediment samples were evaluated by means of sequential extraction scheme, proposed by the Community Bureau of Reference protocol (BCR). The metal content in the extracts was measured by atomic absorption spectrometry. The precision and accuracy of the proposed procedure were evaluated by using a certified reference material BCR 701. The maximum recoveries for heavy metals (HMs) were observed for all three steps of BCR protocol at 32 h total shaking period instead of previously reported 51 h, with p > 0.05. The lixiviation tests (DIN 38414-S4) were used to evaluate the leaching of HMs from sediment samples and it was observed that levels of water extractable HMs were low as compared to those values obtained by acid-soluble fraction of the BCR protocol

  19. Identification of radionuclide partitioning in soils and sediments: Determination of optimum conditions for the exchangeable fraction of the nIST standard sequential extraction protocol

    International Nuclear Information System (INIS)

    We are developing the NIST standard sequential extraction protocol for identifying the fractionation of radioactive elements in soils and sediments. The procedure is designed to partition a soil or sediment sample into six operationally-defined fractions. A full-factorial experimental design/data analysis methodology was used to establish the optimum conditions for the first of these six fractions, called 'exchangeables'. Reaction time, reagent concentration and reaction temperature were chosen as experimental variables. The criteria for choosing optimum conditions were the maximum extraction of 238U combined with a minimum dissolution of non-targeted geochemical phases. Reagent concentration (i.e. ionic strength) is shown to be the controlling factor in the extraction of exchangeable 238U. The optimum (exchangeable) conditions, based on these experiments are: time=1 h; temperature=25 deg. C and concentration=0.4 M MgCl2

  20. Optimization of Ultrasonic-Assisted Extraction of Cordycepin from Cordyceps militaris Using Orthogonal Experimental Design

    Directory of Open Access Journals (Sweden)

    Hsiu-Ju Wang

    2014-12-01

    Full Text Available This study reports on the optimization of the extraction conditions of cordycepin from Cordyceps militaris by using ultrasonication. For this purpose, the orthogonal experimental design was used to investigate the effects of factors on the ultrasonic-assisted extraction (UAE. Four factors: extraction time (min, ethanol concentration (%, extraction temperature (°C and extraction frequency (kHz, were studied. The results showed that the highest cordycepin yield of 7.04 mg/g (86.98% ± 0.23% was obtained with an extraction time of 60 min, ethanol concentration of 50%, extraction temperature of 65 °C and extraction frequency of 56 kHz. It was found that the cordycepin extraction yield increased with the effect of ultrasonication during the extraction process. Therefore, UAE can be used as an alternative to conventional immersion extraction with respect to the recovery of cordycepin from C. militaris, with the advantages of shorter extraction time and reduced solvent consumption.

  1. Laminarin from Irish Brown Seaweeds Ascophyllum nodosum and Laminaria hyperborea: Ultrasound Assisted Extraction, Characterization and Bioactivity

    OpenAIRE

    Kadam, Shekhar U.; Colm P. O'Donnell; Dilip K. Rai; Hossain, Mohammad B.; Catherine M. Burgess; Des Walsh; Tiwari, Brijesh K.

    2015-01-01

    Ultrasound assisted extraction (UAE), purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82...

  2. ULTRASONIC-ASSISTED EXTRACTION OF ANTIOXIDANT PHENOLIC COUMPOUNDS FROM EUCHEUMA COTTONII

    OpenAIRE

    Dyah Hesti Wardhani; Denni Kartika Sari; Aji Prasetyaningrum

    2014-01-01

    The influences of ultrasonic-assisted extraction (UAE) conditions on phenolic compounds of Eucheuma cottonii seaweeed were investigated. The effects of temperature, time and liquid-solid ratio were evaluated based on the total phenolic content (TPC). The result showed a significant variability of effect of temperature, time, and liquid-solid ratio on TPC. Application of ultrasound reduced the optimum temperature, time and liquid-solid ratio of the extraction when compared to the conventional ...

  3. Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology

    OpenAIRE

    Javed Ahamad; Saima Amin; Showkat R. Mir

    2015-01-01

    Background: Momordica charantia Linn. (Cucurbitaceae) fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. Objective: The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. Materials and Methods: Response surface methodology (RSM) was used for the optimization of ultrasound-assisted extraction (UAE) conditions. RSM was based on a three-leve...

  4. EXTRACT

    DEFF Research Database (Denmark)

    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra;

    2016-01-01

    therefore developed an interactive annotation tool, EXTRACT, which helps curators identify and extract standard-compliant terms for annotation of metagenomic records and other samples. Behind its web-based user interface, the system combines published methods for named entity recognition of environment...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL: https://extract.hcmr.gr/....

  5. Response surface optimization of microwave-assisted extraction for HPLC-fluorescence determination of puerarin and daidz

    Institute of Scientific and Technical Information of China (English)

    Ying-Kun Liu; E Yan; Han-Ying Zhan; Zhi-Qi Zhang

    2011-01-01

    Microwave-assisted extraction was optimized with response surface methodology for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii.The optimized extraction procedure was achieved by soaking the sample with 70% methanol

  6. Microwave-assisted hydrothermal extraction of sulfated polysaccharides from Ulva spp. and Monostroma latissimum.

    Science.gov (United States)

    Tsubaki, Shuntaro; Oono, Kiriyo; Hiraoka, Masanori; Onda, Ayumu; Mitani, Tomohiko

    2016-11-01

    Microwave-assisted hydrothermal extraction was applied for production of sulfated polysaccharides from Ulva spp. and Monostroma latissimum. The maximum ulvan yields attained 40.4±3.2% (Ulva meridionalis) and 36.5±3.1% (Ulva ohnoi) within 4min of come-up time and 10min of extraction time at 160°C, respectively. The rhamnan sulfate yield from M. latissimum further attained 53.1±7.2% at 140°C. The sulfated polysaccharides were easily recovered from the extract by simple ethanol precipitation. In addition, molecular weights and viscosity of the extracted polysaccharides could be controlled by varying the extraction temperature. Dielectric measurement revealed that ionic conduction was the important parameter that affect the microwave susceptibility of algae-water mixture. The sulfated polysaccharides extracts are expected as potential feedstock for medical and food applications. PMID:27211652

  7. Microwave-assisted extraction of Shenfu coal and its macromolecule structure

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong; LI Jian-wei; LEI Zhao; GE Ling-mei

    2009-01-01

    Coals consist of some molecules trapped within an organic matrix from which some organic compounds can be extracted by solvents. The Soxhlet technique has been widely used for extracting organic compounds. Microwave heating methods may be successfully applied in the field of coal science. Acetone extraction yields and the chemical composition of the extract were inves-tigated using a typical Chinese coal, Shenfu coal, with microwave-assisted extraction. The acetone extract and residue were ana-lyzed by GC/MS and carbon-13 nuclear magnetic resonance spectroscopy respectively. The carbon spectra were converted into several numerical parameters, fa, Ha, Xb, which indicate the difference in macromolecular structure between Shenfu coal and its residue. Furthermore, a hybrid genetic algorithm was employed using these parameters to approximate a coal macromolecule by assembling the structural fragments or functional groups into a large and complicated structure.

  8. Malva parviflora extract assisted green synthesis of silver nanoparticles

    Science.gov (United States)

    Zayed, Mervat F.; Eisa, Wael H.; Shabaka, A. A.

    2012-12-01

    Five plant leaf extracts (Malva parviflora, Beta vulgaris subsp. Vulgaris, Anethum graveolens, Allium kurrat and Capsicum frutescens) were screened for their bioreduction behavior for synthesis of silver nanoparticles. M. parviflora (Malvaceae) was found to exhibit the best reducing and protecting action in terms of synthesis rate and monodispersity of the prepared silver nanoparticles. Our measurements indicate that biosynthesis of Ag nanoparticles by M. parviflora produces Ag nanoparticles with the diameters in the range of 19-25 nm. XRD studies reveal a high degree of crystallinity and monophasic Ag nanoparticles of face-centered cubic structure. FTIR analysis proved that particles are reduced and stabilized in solution by the capping agent that is likely to be proteins secreted by the biomass. The present process is an excellent candidate for the synthesis of silver nanoparticles that is simple, easy to perform, pollutant free and inexpensive.

  9. Optimization of microwave assisted extraction (MAE) and soxhlet extraction of phenolic compound from licorice root

    OpenAIRE

    Karami, Zohreh; Emam-Djomeh, Zahra; Mirzaee, Habib Allah; Khomeiri, Morteza; Mahoonak, Alireza Sadeghi; Aydani, Emad

    2014-01-01

    In present study, response surface methodology was used to optimize extraction condition of phenolic compounds from licorice root by microwave application. Investigated factors were solvent (ethanol 80 %, methanol 80 % and water), liquid/solid ratio (10:1–25:1) and time (2–6 min). Experiments were designed according to the central composite rotatable design. The results showed that extraction conditions had significant effect on the extraction yield of phenolic compounds and antioxidant capac...

  10. Use of an enzyme-assisted method to improve protein extraction from olive leaves.

    Science.gov (United States)

    Vergara-Barberán, M; Lerma-García, M J; Herrero-Martínez, J M; Simó-Alfonso, E F

    2015-02-15

    The improvement of protein extraction from olive leaves using an enzyme-assisted protocol has been investigated. Using a cellulase enzyme (Celluclast® 1.5L), different parameters that affect the extraction process, such as the influence and amount of organic solvent, enzyme amount, pH and extraction temperature and time, were optimised. The influence of these factors was examined using the standard Bradford assay and the extracted proteins were characterised by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum extraction parameters were: 30% acetonitrile, 5% (v/v) Celluclast® 1.5L at pH 5.0 and 55°C for 15min. Under these conditions, several protein extracts from olive leaves of different genetic variety (with a total protein amount comprised between 1.87 and 6.64mgg(-1)) were analysed and compared by SDS-PAGE, showing differences in their electrophoretic protein profiles. The developed enzyme-assisted extraction method has shown a faster extraction, higher recovery and reduced solvent usage with respect to the use of the non-enzymatic methods described in literature.

  11. Optimization of Microwave-assisted Extraction of Flavonoids from Cryptotaenia japonica Hassk using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Jun Lu

    2013-03-01

    Full Text Available The objective of the study was to optimize the processing of Microwave-Assisted Extraction (MAE of flavonoids from Cryptotaenia japonica Hassk. The effects of processing parameters include ethanol proportion, extraction time, extraction temperature and ratio of liquid to solid on the flavonoids yield were determined and the optimal conditions for flavonoids were evaluated by means of Response Surface Methodology (RSM. The optimal conditions were detected and tri-dimensional response surfaces were plotted from the mathematical models. The F-test and p-value showed that all parameters had highly significant effects on the response value. The optimum extraction conditions were ethanol of 70% (v/v, extraction time of 15 min, extraction temperature of 75°C and liquid to solid ratio of 20 mL/g. Under these conditions, 27.01 mg/g total flavonoids were obtained by Microwave-Assisted Extraction (MAE, which are close to the predicted value (27.48 mg/g. MAE method was applied successfully to extract total flavonoids from Cryptotaenia japonica Hassk

  12. Characterization and functional properties of mango peel pectin extracted by ultrasound assisted citric acid.

    Science.gov (United States)

    Wang, Miaomiao; Huang, Bohui; Fan, Chuanhui; Zhao, Kaili; Hu, Hao; Xu, Xiaoyun; Pan, Siyi; Liu, Fengxia

    2016-10-01

    Pectin was extracted from 'Tainong No. 1' mango peels, using a chelating agent-citric acid as extraction medium by ultrasound-assisted extraction (UAE) and conventional extraction (CE) at temperatures of 20 and 80°C. Chemical structures, rheological and emulsifying properties of mango peel pectins (MPPs) were comparatively studied with laboratory grade citrus pectin (CP). All MPPs exhibited higher protein content (4.74%-5.94%), degree of methoxylation (85.43-88.38%), average molecular weight (Mw, 378.4-2858kDa) than the CP, but lower galacuronic acid content (GalA, 52.21-53.35%). CE or UAE at 80°C resulted in significantly higher pectin yield than those at 20°C, while the extraction time for UAE-80°C (15min) was significantly shorter compared to CE-80°C (2h) with comparable pectin yield. Moreover, MPPs extracted at 80°C were observed with higher GalA and protein content, higher Mw, resulting in higher viscosity, better emulsifying capacity and stability, as compared to those extracted at 20°C and the CP. Therefore, these results suggested that MPPs from 'Tainong No. 1' may become a highly promising pectin with good thickening and emulsifying properties, using ultrasound-assisted citric acid as an efficient and eco-friendly extraction method.

  13. Optimization of ultrasound-assisted extraction of bioactive compounds from wild garlic (Allium ursinum L.).

    Science.gov (United States)

    Tomšik, Alena; Pavlić, Branimir; Vladić, Jelena; Ramić, Milica; Brindza, Ján; Vidović, Senka

    2016-03-01

    Ultrasound-assisted extraction was used for extraction of bioactive compounds and for production of Allium ursinum liquid extract. The experiments were carried out according to tree level, four variables, face-centered cubic experimental design (FDC) combined with response surface methodology (RSM). Temperature (from 40 to 80 °C), ethanol concentration (from 30% to 70%), extraction time (from 40 to 80 min) and ultrasonic power (from 19.2 to 38.4 W/L) were investigated as independent variables in order to obtain the optimal conditions for extraction and to maximize the yield of total phenols (TP), flavonoids (TF) and antioxidant activity of obtained extracts. Experimental results were fitted to the second order polynomial model where multiple regression and analysis of variance were used to determine the fitness of the model and optimal condition for investigated responses. The predicted values of the TP (1.60 g GAE/100 g DW), TF (0.35 g CE/100 g DW), antioxidant activity, IC50 (0.71 mg/ml) and EY (38.1%) were determined at the optimal conditions for ultrasound assisted extraction: 80 °C temperature, 70% ethanol, 79.8 min and 20.06 W/L ultrasonic power. The predicted results matched well with the experimental results obtained using optimal extraction conditions which validated the RSM model with a good correlation. PMID:26563916

  14. Optimized microwave-assisted extraction of 6-gingerol from Zingiber officinale Roscoeand evaluation of antioxidant activity in vitro

    OpenAIRE

    Wei Liu; Chun-Li Zhou; Jing Zhao; Dong Chen; Quan-Hong Li

    2014-01-01

    Background. 6-Gingerol is one of the most pharmacologically active and abundant components in ginger, which has a wide array of biochemical and pharmacologic activities. In recent years, the application of microwave-assisted extraction (MAE) for obtaining bioactive compounds from plant materials has shown tremendous research interest and potential. In this study, an efficient microwave-assisted extraction (MAE) technique was developed to extract 6-gingerol from ginger. The extraction efficien...

  15. Ultrasonic-Assisted Extraction of Raspberry Seed Oil and Evaluation of Its Physicochemical Properties, Fatty Acid Compositions and Antioxidant Activities

    OpenAIRE

    Hui Teng; Lei Chen; Qun Huang; Jinli Wang; Qiyang Lin; Mingxin Liu; Won Young Lee; Hongbo Song

    2016-01-01

    Ultrasonic-assisted extraction was employed for highly efficient separation of aroma oil from raspberry seeds. A central composite design with two variables and five levels was employed and effects of process variables of sonication time and extraction temperature on oil recovery and quality were investigated. Optimal conditions predicted by response surface methodology were sonication time of 37 min and extraction temperature of 54°C. Specifically, ultrasonic-assisted extraction (UAE) was ab...

  16. Comparison of Conventional and Ultrasound-assisted Extraction Techniques on Mass Fraction of Phenolic Compounds from Sage (Salvia officinalis L.)

    OpenAIRE

    M Dent; Dragović-Uzelac, V.; Elez Garofulić, I.; Bosiljkov, T.; Ježek, D.; Brnčić, M.

    2015-01-01

    An innovative ultrasound-assisted extraction (UAE) is the rapid non-thermal extraction technique, which in comparison to conventional extraction (CE), offers high reproducibility in a short time with simplified manipulation, reduced solvent consumption and lower energy. Optimization of ultrasonic conditions was conducted for devices with nominal output power of 100 and 400 W, including the influence of geometrical parameters of probes regarding ultrasound-assisted extraction. The results show...

  17. Application of ionic liquid-based microwave-assisted extraction of flavonoids from Scutellaria baicalensis Georgi.

    Science.gov (United States)

    Zhang, Qin; Zhao, San-Hu; Chen, Jue; Zhang, Li-Wei

    2015-10-01

    In the present work, a rapid ionic liquid-based microwave-assisted extraction (ILMAE) method was successfully applied to simultaneous extraction of baicalin, wogonoside, baicalein and wogonin from Scutellaria baicalensis Georgi. A series of 1-alkyl-3-methylirnidazolium ionic liquids with different anions and cations were assessed for extraction efficiency, and 1-octyl-3-methylimidazolium bromide was selected as the optimal solvent. In addition, the parameters of ILMAE procedure for the four flavonoids were optimized, and the optimal ILMAE method was validated in the linearity, stability, precision and recovery. Meanwhile, the microstructures of S. baicalensis powders were observed before and after extraction with the help of a scanning electron microscope (SEM) in order to explore the extraction mechanism, and the activity of the crude enzyme solution from S. baicalensis was determined through the hydrolysis of baicalin. Finally, the extraction yields and extraction time of WaterHRE, WaterMAE, ILHRE and Chp were 5.18% (30min), 8.77% (90s), 16.94% (30min) and 18.58% (3h), respectively. The results indicated that compared with the conventional extraction approaches, ILMAE possessed great advantages in extracting flavonoids, such as the highest extraction yield (22.28%), the shortest extraction time (90s), etc.

  18. Microwave-Assisted Extraction Studies of Target Analyte Artemisinin from Dried Leaves of Artemisia annua L.

    Directory of Open Access Journals (Sweden)

    Himanshu Misra

    2013-01-01

    Full Text Available Artemisia annua L. (Asteraceae is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. Conventional methods for the extraction of artemisinin from A. annua including solvent extraction, Soxhlet extraction, and heat reflux extraction are characterized by long extraction times and the consumption of large volume of solvents. A simple, rapid, and precise microwave-assisted extraction process was optimized for fast sample preparation for the faster quantitative determination of artemisinin, potential new generation antimalarial drug, from dried leaves of Artemisia annua L. A simple experiment was designed for the optimization of the appropriate solvent under same extraction conditions. The selected appropriate solvent was then standardized for various different extraction variables. The major parameters studied showed effects on extraction efficiency including processing time, strength of microwave, moisture content, volume and nature of the solvent. The most favorable conditions were obtained by using plant material of 25 mesh (particle size extracted with acetone for 120 seconds at 160 W (i.e., 20% of total power. Quantitative analysis was performed using thin-layer chromatography coupled with a densitometer (TLC densitometry. The results showed that MAE can be used as an efficient and rapid method for the extraction of the active components from plants.

  19. Determination of Pt from coke samples by ICP-MS after microwave assisted digestion and microwave assisted cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Niemela, M.; Huttunen, S.M.; Gornostayev, S.S.; Peramaki, P. [University of Oulu, Oulu (Finland). Dept. of Chemistry

    2009-09-15

    Platinum in coke samples was determined by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted sample digestion and temperature controlled microwave assisted cloud point extraction (MW-CPE). Interferences due to hafnium were successfully eliminated using MW-CPE with 2-MBT prior to the determination of platinum by ICP-MS. The validity of the method was studied by spike recovery tests and by analyzing certified reference material (BCR-723 street dust). The results obtained for platinum in the BCR-723 were generally in good agreement with the certified values. Furthermore, the preliminary platinum results obtained for coke sample by ICP-MS after MW-CPE were compared to those obtained by a reference method (NiS-Fire Assay preconcentration/Te coprecipitation and ICP-MS determination).

  20. Sequential leaching extraction of 239,240Pu, 238Pu, 241Pu, 237Np and 241Am from a mud sample: An intercomparison study

    International Nuclear Information System (INIS)

    The transuranics content of a mud sample taken from a nuclear waste storage container was analysed employing two different sequential extraction methods. The following fractions were isolated: (1)Water soluble (2) Readily available (3) Carbonate bound and specifically adsorbed (4) Organically bound (5) Oxide and hydroxides bound and (6) residual. Both methods differ in the reagents employed, the extraction sequence applied as well as the temperature and means of extraction. The 239,240Pu, 238Pu, 237Np and 241Am extracted in each phase were determined using standard radiochemical procedures. 241Pu was analysed through the 241Am in-growth on just one old disk of the residual fraction containing plutonium. Plutonium was mainly associated to organic-oxides fractions (89-92 %). The percentage extracted in each fraction depended on the method and the extraction sequence used. The soluble fraction of plutonium was less than 13%. Neptunium seemed to be the more soluble than the other transuranics (27%) and the americium showed a tendency to be associated to carbonates (30%). (author)

  1. Portable microwave assisted extraction: An original concept for green analytical chemistry.

    Science.gov (United States)

    Perino, Sandrine; Petitcolas, Emmanuel; de la Guardia, Miguel; Chemat, Farid

    2013-11-01

    This paper describes a portable microwave assisted extraction apparatus (PMAE) for extraction of bioactive compounds especially essential oils and aromas directly in a crop or in a forest. The developed procedure, based on the concept of green analytical chemistry, is appropriate to obtain direct in-field information about the level of essential oils in natural samples and to illustrate green chemical lesson and research. The efficiency of this experiment was validated for the extraction of essential oil of rosemary directly in a crop and allows obtaining a quantitative information on the content of essential oil, which was similar to that obtained by conventional methods in the laboratory.

  2. Review and evaluation of extractants for strontium removal using magnetically assisted chemical separation

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, C.B.; Rogers, R.D. [Northern Illinois Univ., De Kalb, IL (United States). Dept. of Chemistry; Nunez, L.; Ziemer, M.D.; Pleune, T.T.; Vandegrift, G.F. [Argonne National Lab., IL (United States)

    1995-11-01

    A literature review on extractants for strontium removal was initially performed at Northern Illinois University to assess their potential in magnetically assisted chemical separation. A series of potential strontium extractants was systematically evaluated there using radioanalytical methods. Initial experiments were designed to test the uptake of strontium from nitric acid using several samples of magnetic extractant particles that were coated with various crown ether ligands. High partition coefficient (K{sub d}) values for stimulant tank waste were obtained. Further studies demonstrated that the large partitioning was due to uncoated particles.

  3. Evaluating the Mobility of Arsenic in Synthetic Iron-containing Solids Using a Modified Sequential Extraction Method

    OpenAIRE

    Shan, Jilei; Sáez, A. Eduardo; Ela, Wendell P.

    2010-01-01

    Many water treatment technologies for arsenic removal that are used today produce arsenic-bearing residuals which are disposed in non-hazardous landfills. Previous works have established that many of these residuals will release arsenic to a much greater extent than predicted by standard regulatory leaching tests (e.g. the toxicity characteristic leaching procedure, TCLP) and, consequently, require stabilization to ensure benign behavior after disposal. In this work, a four-step sequential ex...

  4. Batch and Continuous Ultrasound Assisted Extraction of Boldo Leaves (Peumus boldus Mol.).

    Science.gov (United States)

    Petigny, Loïc; Périno-Issartier, Sandrine; Wajsman, Joël; Chemat, Farid

    2013-01-01

    Vegetal extracts are widely used as primary ingredients for various products from creams to perfumes in the pharmaceutical, nutraceutic and cosmetic industries. Having concentrated and active extract is essential, as the process must extract as much soluble material as possible in a minimum time, using the least possible volume of solvent. The boldo leaves extract is of great interest for the industry as it holds a great anti-oxidant activity due to high levels of flavonoids and alkaloids such as boldine. Ultrasound Assisted Extraction (UAE) has been used to improve the efficiency of the plant extraction, reducing extraction time, increasing the concentration of the extract with the same amount of solvent and plant material. After a preliminary study, a response surface method has been used to optimize the extraction of soluble material from the plant. The results provided by the statistical analysis revealed that the optimized conditions were: sonication power 23 W/cm2 for 40 min and a temperature of 36 °C. The optimized parameters of the UAE provide a better extraction compared to a conventional maceration in terms of process time (30 min instead of 120 min), higher yield, more energy saving, cleanliness, safety and product quality. PMID:23481637

  5. Batch and Continuous Ultrasound Assisted Extraction of Boldo Leaves (Peumus boldus Mol.

    Directory of Open Access Journals (Sweden)

    Joël Wajsman

    2013-03-01

    Full Text Available Vegetal extracts are widely used as primary ingredients for various products from creams to perfumes in the pharmaceutical, nutraceutic and cosmetic industries. Having concentrated and active extract is essential, as the process must extract as much soluble material as possible in a minimum time, using the least possible volume of solvent. The boldo leaves extract is of great interest for the industry as it holds a great anti-oxidant activity due to high levels of flavonoids and alkaloids such as boldine. Ultrasound Assisted Extraction (UAE has been used to improve the efficiency of the plant extraction, reducing extraction time, increasing the concentration of the extract with the same amount of solvent and plant material. After a preliminary study, a response surface method has been used to optimize the extraction of soluble material from the plant. The results provided by the statistical analysis revealed that the optimized conditions were: sonication power 23 W/cm2 for 40 min and a temperature of 36 °C. The optimized parameters of the UAE provide a better extraction compared to a conventional maceration in terms of process time (30 min instead of 120 min, higher yield, more energy saving, cleanliness, safety and product quality.

  6. Extraction of valuable compounds from mangosteen pericarps by hydrothermal assisted sonication

    Science.gov (United States)

    Machmudah, Siti; Lestari, Sarah Duta; Shiddiqi, Qifni Yasa'Ash; Widiyastuti, Winardi, Sugeng; Wahyudiono, Kanda, Hideki; Goto, Motonobu

    2015-12-01

    Valuable compounds, such as xanthone and phenolic compounds, from mangosteen pericarps was extracted by hydrothermal treatment at temperatures of 120-160 °C and pressures of 5 MPa using batch and semi-batch extractor. This method is a simple and environmentally friendly extraction method requiring no chemicals other than water. Under these conditions, there is possibility for the formation of phenolic compounds from mangosteen pericarps from decomposition of bounds between lignin, cellulose, and hemicellulose via autohydrolysis. In order to increase the amount of extracted valuable compounds, sonication pre-treament was performed prior to the hydrothermal extraction process. 30 min of sonication pre-treatment could increase significantly the amount of xanthone and phenolic compounds mangosteen pericarps extraction. In batch-system, the xanthone recovery approach to 100 % at 160 °C with 30 min sonication pre-treatment for 150 min extraction time. Under semi-batch process, the total phenolic compounds in the extract was 217 mg/g sample at 160 °C with 30 min sonication pre-treatment for 150 min total extraction time. The results revealed that hydrothermal extraction assisted sonication pre-treatment is applicable method for the isolation of polyphenolic compounds from other types of biomass and may lead to an advanced plant biomass components extraction technology.

  7. Fatty Acid Characteristics of Isochrysis galbana Lipids Extracted Using a Microwave-Assisted Method

    Directory of Open Access Journals (Sweden)

    Cherng-Yuan Lin

    2015-02-01

    Full Text Available Lipids were extracted from Isochrysis galbana using a microwave-assisted method accompanied by various types of organic solvents. The effects of organic solvent type and microwave input energy on the fatty acid characteristics of the extracted lipids and their biodiesel product were investigated. Variations in the characteristics of the lipids extracted using a combination of n-hexane and iso-propanol solvents in both emulsion and direct mixtures were also compared. The experimental results showed that greater quantities of Isochrysis galbana lipids, and fatty acid methyl esters transesterified from those lipids, were extracted when using microwave irradiation with an organic solvent mixture of n-hexane and isopropanol in a 2:1 volumetric ratio than when using either n-hexane or isopropanol as the sole solvent. A greater quantity of Isochrysis galbana lipids was extracted when an emulsion of isopropanol solvent evenly dispersed in the continuous phase of n-hexane solvent was used than when a direct mixture of the two solvents was used. In addition, the quantity of lipids extracted from the dried Isochrysis galbana powder with the assistance of microwave irradiation was 9.08 wt% greater than when using traditional Soxhlet extraction without microwave irradiation.

  8. Solvent effects on focused microwave assisted extraction of polyphenolic acids from Eucommia ulmodies.

    Science.gov (United States)

    Li, Hui; Chen, Bo; Nie, Lihua; Yao, Shouzhuo

    2004-01-01

    An open microwave-assisted extraction system was used to extract gallic acid, protocatechuic acid, chlorogenic acid and caffeic acid from Eucommia ulmodies. The effect of extraction variables, especially solvent, on the recoveries of these polyphenolic compounds was investigated using factorial design. As extracting solvent for these compounds, methanol produced a higher recovery than pure water. For straight chain alcohol solvents, the lower the carbon number, the higher the recoveries of the polyphenolic acids. The optimal ratio of methanol:water:glacial acetic acid in the solvent mixture used in microwave-assisted extraction was 2:8:0.3 (v/v) and this solvent could be directly used as the mobile phase in HPLC separation without additional intermittent treatment as reported in literature. The extraction under the condition of 50% microwave power and 30 s irradiation at a solvent:sample ratio of 10 (mL/g) was found to be the most advantageous. The repeatability test of extraction and chromatographic analysis was satisfactory for the analysis of these polyphenolic compounds. PMID:15508835

  9. Extraction of Natural Antioxidants from the Thelephora ganbajun Mushroom by an Ultrasound-Assisted Extraction Technique and Evaluation of Antiproliferative Activity of the Extract against Human Cancer Cells

    Science.gov (United States)

    Xu, Dong-Ping; Zheng, Jie; Zhou, Yue; Li, Ya; Li, Sha; Li, Hua-Bin

    2016-01-01

    The Thelephora ganbajun mushroom has been found to be a potential rich source of natural antioxidants. In this study, an ultrasound-assisted extraction (UAE) technique together with GRAS (generally recognized as safe) solvents (ethanol and water) was used to maximize the extraction of antioxidants from Thelephora ganbajun. Five extraction parameters (ethanol concentration, solvent to solid ratio, extraction time, temperature and ultrasound power) were investigated by single-factor experiments, and then a central composite rotatable design was employed to study interaction of three key extraction parameters. The optimum conditions were as follows: 57.38% ethanol, 70.15 mL/g solvent to solid ratio, 10.58 min extraction time, 40 °C extraction temperature and 500 W ultrasound power. Under the optimum conditions, the antioxidant activity obtained was 346.98 ± 12.19 µmol Trolox/g DW, in accordance with the predicted value of 344.67 µmol Trolox/g DW. Comparison of UAE with conventional maceration and Soxhlet extraction, the UAE method showed stronger extract efficiency in a shorter extraction time. These results showed that UAE was an effective technique to extract antioxidants from Thelephora ganbajun. Furthermore, the extracts obtained under the optimized conditions exhibited antiproliferative activities toward human lung (A549), breast (MCF-7), liver (HepG2) and colon (HT-29) cancer cells, especially for liver and lung cancer cells. In addition, rutin, 2-hydrocinnamic acid and epicatechin were identified in the extract, which might contribute to antioxidant and antiproliferative activities. PMID:27706082

  10. Ultrasound-assisted extraction of hemicelluloses from grape pomace using response surface methodology.

    Science.gov (United States)

    Minjares-Fuentes, R; Femenia, A; Garau, M C; Candelas-Cadillo, M G; Simal, S; Rosselló, C

    2016-03-15

    An ultrasound-assisted procedure was applied to the extraction of hemicelluloses from grape pomace at a mild temperature (20°C). A Central composite design (CCD) was employed to optimize the ultrasound-assisted extraction (UAE) of hemicelluloses from grape pomace with the aim to maximize their extraction yield, and, also, the obtention of the main polymers forming this fraction: Xyloglucans (XLG), Mannans (MAN) and Xylans (XN). Extraction time (X1), solid:liquid ratio (X2) and KOH concentration (X3) were the variables used to optimize the process. The conditions that maximize (1) the extraction yield of hemicelluloses and the contents of (2) XLG, (3) MAN and (4) XN, were: (1) X1=2.6h; X2=1:48 (w/v); X3=0.4M, (2) X1=2.9h; X2=1:57 (w/v); X3=2.25M, (3) X1=2.7h; X2=1:58(w/v);X3=2.2M, and (4) X1=3h; X2=1:60 (w/v); X3=2.3M, respectively. Under these conditions, the maximum extraction yield of hemicelluloses, XLG, MAN and XN contents were: ∼7.9±0.2%, ∼3.6±0.02%, ∼1.1±0.04% and ∼1.2±0.02%, respectively. Close agreement between experimental and predicted values was found. The results suggest that the ultrasound-assisted extraction could be a good option for the extraction of hemicellulosic polysaccharides from grape pomace at industrial level. PMID:26794751

  11. Response surface optimization of enzyme-assisted extraction polysaccharides from Dictyophora indusiata.

    Science.gov (United States)

    Wu, Songhai; Gong, Guili; Wang, Yanyan; Li, Feng; Jia, Shaoyi; Qin, Fengxiang; Ren, Haitao; Liu, Yong

    2013-10-01

    An enzyme-assisted procedure for the extraction of the water-soluble polysaccharides from the stipe of Dictyophora indusiata was investigated using response surface methodology. The orthogonal array design was employed to optimize the concentration of three kinds of enzyme (cellulase, papain and pectolyase) and the optimal cellulose, papain and pectolyase concentration were 2.0% (wt.% of D. indusiata powder), 2.0% and 1.5%, respectively. And then the effect such as temperature, time and pH was studied based on a three-level three-factor Box-Behnken design. The optimized conditions were as follows: extraction temperature 52.5 °C, extraction time 105 min and pH 5.25. Under these conditions, the experimental yield of polysaccharides was 9.77±0.18%, which was well matched with the predictive yield of 9.87%. As it turned out, enzyme-assisted procedure was an effective method.

  12. Microwave—assisted Extraction of Effective Compounds from Traditional Chinese Herbal Medicine Ciwujia

    Institute of Scientific and Technical Information of China (English)

    王娟; 沈平孃; 沈永嘉

    2003-01-01

    Microwave-assisted extraction (MAE) fro active ingredients in Ciweujia was studied by using ethanol as the extractant.Comparing MAE with conventional methods,the former can save the extracting time and increase the content of the active ingredients in product,As to the operation in MAE ,the continuous radiation process is more convenient for the extraction for traditional Chinese medicine than the intermittent radiation process,Optimized by uniform design,MAE was proved to be an effective and novel process for extracting active ingredients in Ciwujia,The optimized MAE conditions are as follows:the microwave power is 510W,the radiation time 30 min the alohol concentration at 80%,the ratio of solvent to soild material being 5:1,the soaking time 0.5h ,and the herbal particle size is (520±19)μm.

  13. Ultrasound-assisted extraction of bioactive compounds from lemon balm and peppermint leaves

    Science.gov (United States)

    Šic Žlabur, Jana; Voća, Sandra; Dobričević, Nadica; Pliestić, Stjepan; Galić, Ante; Boričević, Ana; Borić, Nataša

    2016-01-01

    The aim of this study was to investigate the influence of conventional and ultrasound-assisted extraction (frequency, time, temperature) on the content of bioactive compounds as well as on the antioxidant activity of aqueous extracts from fresh lemon balm and peppermint leaves. Total phenols, flavonoids, non-flavonoids, total chlorophylls, total carotenoids, and radical scavenging capacity were determined. Moreover, the relationship between bioactive compounds and antioxidant capacity was studied by linear regression. A significant increase in all studied bioactive compounds during ultrasonic extraction for 5 to 20 min was found. With the classical extraction method, the highest amounts of total phenols, flavonoids, and antioxidant activity were determined, and the maximum amounts of total chlorophylls and carotenoids were determined during 20 min ultrasonic extraction. The correlation analysis revealed a strong, positive relationship between antioxidant activity and total phenolic compounds.

  14. Optimization of Ultrasound-Assisted Extraction of Anthocyanins from Mulberry, Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ren-You Gan

    2011-05-01

    Full Text Available Mulberry is one of the most widely used traditional Chinese medicines. Anthocyanins are the main bioactive components of mulberry, and possess important biological activities, such as antimicrobial, anti-inflammatory and antioxidant activities. This study investigated the ultrasound-assisted extraction (UAE of anthocyanins from mulberry by using response surface methodology (RSM. The extraction conditions associated with anthocyanin yield, including extraction solvent, liquid-to-solid rate, temperature and extraction time, are discussed. The optimal conditions obtained by RSM for UAE from mulberry include 63.8% methanol contains 1% (v/v trifluoroacetic acid (TFA, 43.2 °C temperature, 23.8 (v/w liquid-to-solid ratio, and 40 min time for the maximum yield (64.70 ± 0.45 mg/g. The results indicated that the UAE can be an effective method for the extraction of some active components from plant materials.

  15. Response surface optimization of ultrasound assisted extraction of pectin from pomegranate peel.

    Science.gov (United States)

    Moorthy, I Ganesh; Maran, J Prakash; Surya, S Muneeswari; Naganyashree, S; Shivamathi, C S

    2015-01-01

    Ultrasound assisted extraction of pectin from waste pomegranate peel was investigated and optimized using Box-Behnken response surface design coupled with numerical optimization technique. The individual and interactive effect of process variables (solid-liquid ratio, pH, extraction time and temperature) on the pectin yield was studied. The experimental data obtained were analyzed by Pareto analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R(2)) value. The optimal extraction condition was found to be 1:17.52 g/ml of solid-liquid ratio, 1.27 of pH, 28.31 min of extraction time and 61.90 °C of extraction temperature respectively. Under the optimal conditions, experimental yield was very close to the predicted values.

  16. Antioxidant Activity and Phenolic Content of Microwave-Assisted Solanum melongena Extracts

    Directory of Open Access Journals (Sweden)

    Loredana Salerno

    2014-01-01

    Full Text Available Eggplant fruit is a very rich source of polyphenol compounds endowed with antioxidant properties. The aim of this study was to extract polyphenols from eggplant entire fruit, pulp, or skin, both fresh and dry, and compare results between conventional extraction and microwave-assisted extraction (MAE. The effects of time exposure (15, 30, 60, and 90 min and solvent (water 100% or ethanol/water 50% were also evaluated. The highest amount of polyphenols was found in the extract obtained from dry peeled skin treated with 50% aqueous ethanol, irradiated with microwave; this extract contained also high quantity of flavonoids and showed good antioxidant activity expressed by its capacity to scavenge superoxide anion and to inhibit lipid peroxidation.

  17. THE LIBERATION OF ARSENOSUGARS FROM MATRIX COMPONENTS IN DIFFICULT TO EXTRACT SEAFOOD SAMPLES UTILIZING TMAOH/ACETIC ACID SEQUENTIALLY IN A TWO-STAGE EXTRACTION PROCESS

    Science.gov (United States)

    Sample extraction is one of the most important steps in arsenic speciation analysis of solid dietary samples. One of the problem areas in this analysis is the partial extraction of arsenicals from seafood samples. The partial extraction allows the toxicity of the extracted arse...

  18. Speciation Analysis of 129I and 127I in Aerosols Using Sequential Extraction and Mass Spectrometry Detection

    DEFF Research Database (Denmark)

    Zhang, Luyuan; Hou, Xiaolin; Xu, Sheng

    2015-01-01

    A new analytical method has been developed for speciation analysis of 127I and 129I in aerosols collected on polypropylene (PP) filter paper. Iodide, iodate, NaOH soluble iodine, and insoluble iodine were separated from aerosols using sequential extraction, chromatography separation, and alkaline...... ashing and measured using inductive coupled plasma mass spectrometry (ICP-MS) for 127I and accelerator mass spectrometry (AMS) for 129I. Parameters affecting the leaching efficiency and stability of iodine species, such as leaching time and temperature, amount of alkaline reagent for ashing, ashing...... temperature and time, and iodine protective agent, were investigated and optimized. It was observed that long time water leaching would change inorganic iodine species due to photochemical oxidation of iodide on the PP filter surface. NaOH leaching can only extract less than 60% of iodine from the studied...

  19. Trace metal distribution in the Arosa estuary (N.W. Spain): The application of a recently developed sequential extraction procedure for metal partitioning

    International Nuclear Information System (INIS)

    A study of the trace metal distribution in sediment samples from the Galician coast (Spain) has been performed. A multielement extraction method optimised via experimental design has been employed. The method uses centrifugation to pass the extractant solution at varying pH, through the sediment sample. The sequential leaches were collected and analysed by ICP-AES. Chemometric approaches were utilised to identify the composition of the physico-chemical components in order to characterise the sample. The samples collected at different sites could be classified according to their differences in metal bio-availability and important information regarding element distribution within the physico-chemical components is given. The method has proved to be a quick and reliable way to evaluate sediment samples for environmental geochemistry analysis. In addition, this approach has potential as fast screening method for the bio-availability of metals in the environment

  20. 土壤重金属连续提取方法的优化%Optimization of Soil Heavy Metal Sequential Extraction Procedures

    Institute of Scientific and Technical Information of China (English)

    刘丹丹; 刘菲; 缪德仁

    2015-01-01

    重金属在污染土壤中的形态分布决定着重金属的迁移性和危害的程度。土壤重金属形态分析应用最多的是Tessi-er和BCR连续提取法。Tessier和BCR连续提取法没有考虑土壤样品的特征。美国环保署危险废物浸出毒性鉴别标准法虽然考虑土壤pH值,但没有划分形态。采集不同pH土样,结合Tessier、BCR和毒性浸出鉴别方法的特征,优化出针对不同pH值土壤的连续提取方法,将土壤中重金属划分为活性态、次生碳酸盐结合态、次稳定态和稳定态。用优化的连续提取方法对土样进行连续提取,重金属回收率为85%~115%。优化连续提取方法的结果与Tessier和BCR结果对比显示优化连续提取方法克服了Tessier连续提取法对非石灰质土壤提取过量BCR连续提取法对石灰质土壤提取不足的缺点。优化后的连续提取方法数据稳定可靠,可作为重金属形态分析方法使用。%The environmental risks of heavy metals depend on its speciation distribution in contaminated soils. The chemical speciation analysis was one of the hot topics in environmental sciences.In recent years,the most popular sequential extraction procedures were Tessier and BCR.Nethier Tessier nor BCR sequential extraction methods considered the characteristics of soil samples.Although Toxicity Characteristic Leaching Procedure (TCLP)used two different extraction regent is based on the pH values of soil samples,it is a single step extrac-tion method.In this paper,compared with Tessier,BCR and TCLP extraction techniques,the speciation extrac-tion method was optimized in order to adapt soils with different pH values.The heavy metals in the soils were di-vided into active fraction,secondary carbonate fraction,secondary steady fraction and steady fraction.The re-sults show that the optimized sequential extraction method is more stable,the recovery rate is 85% to 1 15%which could satisfy the soil speciation

  1. Evaluation of the three-stage bcr (european community bureau of reference) sequential extraction procedure to assess the potential mobility and toxicity of heavy metals in roadside soils

    International Nuclear Information System (INIS)

    The geochemical properties of roadside soils, specifically the association of metals with operationally defined solid fractions, were characterized. The new optimized four-step (acid extractable, reducible, oxidizable, and residual) sequential extraction procedure was applied to five roadside soils from an urban city, Lagos, Nigeria. Three elements were examined (Pb, Cu and Zn) in the < 250-mu m fraction. Data so obtained indicated that more than 50% of the metals were associated with the residual fraction, reflecting lithogenic-pedogenic control. Zinc had one-sixth of its quantity in the most mobile and/or bioavailable fraction, which is susceptible to release into solution with the decrease in pH. The amount of lead associated with the reducible fraction was significant, while an appreciable amount of copper was associated with oxidizable fraction (19%). (author)

  2. Ionic liquid-based microwave-assisted extraction of rutin from Chinese medicinal plants.

    Science.gov (United States)

    Zeng, Huan; Wang, Yuzhi; Kong, Jinhuan; Nie, Chan; Yuan, Ya

    2010-12-15

    An ionic liquid-based microwave-assisted extraction (ILMAE) method has been developed for the effective extraction of rutin from Chinese medicinal plants including Saururus chinensis (Lour.) Bail. (S. chinensis) and Flos Sophorae. A series of 1-butyl-3-methylimidazolium ionic liquids with different anions were investigated. The results indicated that the characteristics of anions have remarkable effects on the extraction efficiency of rutin and among the investigated ionic liquids, 1-butyl-3-methylimidazolium bromide ([bmim]Br) aqueous solution was the best. In addition, the ILMAE procedures for the two kinds of medicinal herbs were also optimized by means of a series of single factor experiments and an L(9) (3(4)) orthogonal design. Compared with the optimal ionic liquid-based heating extraction (ILHE), marinated extraction (ILME), ultrasonic-assisted extraction (ILUAE), the optimized approach of ILMAE gained higher extraction efficiency which is 4.879 mg/g in S. chinensis with RSD 1.33% and 171.82 mg/g in Flos Sophorae with RSD 1.47% within the shortest extraction time. Reversed phase high performance liquid chromatography (RP-HPLC) with ultraviolet detection was employed for the analysis of rutin in Chinese medicinal plants. Under the optimum conditions, the average recoveries of rutin from S. chinensis and Flos Sophorae were 101.23% and 99.62% with RSD lower than 3%, respectively. The developed approach is linear at concentrations from 42 to 252 mg L(-1) of rutin solution, with the regression coefficient (r) at 0.99917. Moreover, the extraction mechanism of ILMAE and the microstructures and chemical structures of the two researched samples before and after extraction were also investigated. With the help of LC-MS, it was future demonstrated that the two researched herbs do contain active ingredient of rutin and ionic liquids would not influence the structure of rutin.

  3. Comparison between BCR sequential extraction and geo-accumulation method to evaluate metal mobility in sediments of Dongting Lake, Central China

    Science.gov (United States)

    Yao, Zhigang

    2008-02-01

    The form in which a metal exists strongly influences its mobility and thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. The Dongting Lake, the second largest fresh-water lake in China, contains three China wetlands of international importance, the East Dongting Lake, South Dongting Lake, and West Dongting Lake. In this work, an optimized BCR sequential extraction procedure was used to assess the environmental risk of Cd, Cr, Cu, Ni, Pb and Zn in contaminated sediment of the Dongting Lake. The procedure was evaluated by using a certified reference material, BCR701. The results of the partitioning study indicated that in the lake sediments, more easily mobilized forms (acid exchangeable) were predominant for Cd, particularly in the samples from the East Dongting Lake. In contrast, the largest amount of Pb was associated with the iron and manganese oxide fractions and Cu, Zn, Cr, and Ni analyzed were mainly distributed in residual phase at an average percentage greater than 60% of the total metals. The potential risk to the lake’s water contamination was highest in the East Dongting Lake based on the calculated contamination factors. On the other hand, the total metal content was determined as well by inductively coupled plasma and mass spectrometry (ICP-MS) and assessed by using geo-accumulation index. The assessment results using geo-accumulation index were compared with the information on metal speciation. Both were correspondent with each other.

  4. Sequential cloud-point extraction for toxicological screening analysis of medicaments in human plasma by high pressure liquid chromatography with diode array detector.

    Science.gov (United States)

    Madej, Katarzyna; Persona, Karolina; Wandas, Monika; Gomółka, Ewa

    2013-10-18

    A complex extraction system with the use of cloud-point extraction technique (CPE) was developed for sequential isolation of basic and acidic/neutral medicaments from human plasma/serum, screened by HPLC/DAD method. Eight model drugs (paracetamol, promazine, chlorpromazine, amitriptyline, salicyclic acid, opipramol, alprazolam and carbamazepine) were chosen for the study of optimal CPE conditions. The CPE technique consists in partition of an aqueous sample with addition of a surfactant into two phases: micelle-rich phase with the isolated compounds and water phase containing a surfactant below the critical micellar concentration, mainly under influence of temperature change. The proposed extraction system consists of two chief steps: isolation of basic compounds (from pH 12) and then isolation of acidic/neutral compounds (from pH 6) using surfactant Triton X-114 as the extraction medium. Extraction recovery varied from 25.2 to 107.9% with intra-day and inter-day precision (RSD %) ranged 0.88-1087 and 5.32-17.96, respectively. The limits of detection for the studied medicaments at λ 254nm corresponded to therapeutic or low toxic plasma concentration levels. Usefulness of the proposed CPE-HPLC/DAD method for toxicological drug screening was tested via its application to analysis of two serum samples taken from patients suspected of drug overdosing.

  5. Optimization of ultrasound-assisted extraction to obtain mycosterols from Agaricus bisporus L. by response surface methodology and comparison with conventional Soxhlet extraction.

    Science.gov (United States)

    Heleno, Sandrina A; Diz, Patrícia; Prieto, M A; Barros, Lillian; Rodrigues, Alírio; Barreiro, Maria Filomena; Ferreira, Isabel C F R

    2016-04-15

    Ergosterol, a molecule with high commercial value, is the most abundant mycosterol in Agaricus bisporus L. To replace common conventional extraction techniques (e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that solvents, time and ultrasound power altered the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5 ± 0.5mg ergosterol/100 g dw. However, with n-hexane extracts with higher purity (mg ergosterol/g extract) were obtained. Finally, it was proposed for the removal of the saponification step, which simplifies the extraction process and makes it more feasible for its industrial transference. PMID:26675841

  6. Optimization of ultrasound-assisted extraction to obtain mycosterols from Agaricus bisporus L. by response surface methodology and comparison with conventional Soxhlet extraction.

    Science.gov (United States)

    Heleno, Sandrina A; Diz, Patrícia; Prieto, M A; Barros, Lillian; Rodrigues, Alírio; Barreiro, Maria Filomena; Ferreira, Isabel C F R

    2016-04-15

    Ergosterol, a molecule with high commercial value, is the most abundant mycosterol in Agaricus bisporus L. To replace common conventional extraction techniques (e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that solvents, time and ultrasound power altered the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5 ± 0.5mg ergosterol/100 g dw. However, with n-hexane extracts with higher purity (mg ergosterol/g extract) were obtained. Finally, it was proposed for the removal of the saponification step, which simplifies the extraction process and makes it more feasible for its industrial transference.

  7. Extraction of Maltol from Fraser Fir: A Comparison of Microwave-Assisted Extraction and Conventional Heating Protocols for the Organic Chemistry Laboratory

    Science.gov (United States)

    Koch, Andrew S.; Chimento, Clio A.; Berg, Allison N.; Mughal, Farah D.; Spencer, Jean-Paul; Hovland, Douglas E.; Mbadugha, Bessie; Hovland, Allan K.; Eller, Leah R.

    2015-01-01

    Two methods for the extraction of maltol from Fraser fir needles are performed and compared in this two-week experiment. A traditional benchtop extraction using dichloromethane is compared to a microwave-assisted extraction using aqueous ethanol. Students perform both procedures and weigh the merits of each technique. In doing so, students see a…

  8. Efficient extraction of olive pulp and stone proteins by using an enzyme-assisted method.

    Science.gov (United States)

    Vergara-Barberán, María; Lerma-García, María Jesús; Herrero-Martínez, José Manuel; Simó-Alfonso, Ernesto Francisco

    2014-07-01

    An efficient protein extraction protocol for proteins from olive pulp and stone by using enzymes was developed. For this purpose, different parameters that affect the extraction process, such as enzyme type and content, pH, and extraction temperature and time, were tested. The influence of these factors on protein recovery was examined using the standard Bradford assay, while the extracted proteins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The best extraction conditions were achieved at pH 7.0 and 5% (v/v) Palatase® 20000 L (lipase) for pulp and Lecitase® Ultra (phospholipase) for stone proteins. The optimal extraction temperature and time were 30 and 40 °C for 15 min for pulp and stone tissues, respectively. Under these conditions, several protein extracts coming from olive fruits of different genetic variety were analyzed, their profiles being compared by SDS-PAGE. The developed enzyme-assisted extraction method showed faster extraction, higher recovery, and reduced solvent usage than the nonenzymatic methods previously described in the literature. In the case of stone proteins, different electrophoretic profiles and band intensities were obtained that could be helpful to distinguish samples according to their genetic variety.

  9. Ultrasound-assisted extraction of hesperidin from Penggan (Citrus reticulata) peel.

    Science.gov (United States)

    Ma, Yaqin; Ye, Xingqian; Hao, Yunbin; Xu, Guoneng; Xu, Guihua; Liu, Donghong

    2008-03-01

    Hesperidin, an abundant and inexpensive bioflavonoid in Penggan (Citrus reticulata) peel, has been reported to possess a wide range of pharmacological properties. Ultrasonic extraction is an effective technique for the isolation of bioactive compounds from vegetable materials. In this study, the application of ultrasonic method was shown to be more efficient in extracting hesperidin from Penggan (C. reticulata) peel than the classical method. The effects of main ultrasonic-assisted extraction conditions on extraction yields of hesperidin from Penggan (C. reticulata) peel were evaluated, including extraction solvents, solvent volume, temperature, extraction time, ultrasonic power, ultrasonic frequency. Results showed that solvent, frequency and processing temperature were the most important factors for improving the extracting yields of hesperidin. When performed at the same temperature under the same time using three frequencies, methanol as the solvent improved the extraction yield evidently compared with ethanol or isopropanol; by comparison of the frequency influence, the yield of hesperidin was higher at 60 kHz than at 20 kHz and 100 kHz. The optimum ultrasonic conditions were determined as: methanol, frequency of 60 kHz, extraction time of 60 min, and temperature of 40 degrees C. In addition, the ultrasonic power had a weak effect on the yields of hesperidin within the experimental range. Extending ultrasonic treatment times did not result in degradation of hesperidin; the rotary beaker for materials can increase the yields of hesperidin. PMID:17584518

  10. The effects of temperature and frequencies in ultrasound assisted extraction of phycocyanin from microalgae Spirulina sp

    International Nuclear Information System (INIS)

    Microalgae Spirulina sp has been identified as source of protein and other high added value compounds. One of the compounds is phycocyanin as also known for antioxidant use. The extraction of this compound by using conventional method (soxhlet extraction) resulted low yield and longer processing time. This research was aimed to extract phycocyanin by using an extraction assisted by ultrasound irradiation. The extraction was performed by using variable of ultrasound frequency and extraction temperature and ethanol was used as a solvent. The result showed that yield of phycocyanin extracted by conventional method was 11.13% while the ultrasound irradiation could increase the yield up to 15.61% at constant frequency of 42 kHz, while the optimum temperature was obtained at 45°C. The analysis of variable interactions showed that both temperature and time has an interaction and temperature was the highest variable in increasing the yield. The conclusion of this research was the ultrasound could improve significantly the efficiency of extraction as well as activity of phycocyanin extracted from microalgae

  11. The effects of temperature and frequencies in ultrasound assisted extraction of phycocyanin from microalgae Spirulina sp

    Energy Technology Data Exchange (ETDEWEB)

    Hadiyanto,, E-mail: hadiyanto@live.undip.ac.id; Suttrisnorhadi,; Soetrisnanto, Danny; Azizah, Nur [Department of Chemical Engineering, Diponegoro University, Jl. Prof. Soedarto, SH-Tembalang, Semarang 50239 INDONESIA (Indonesia); Sutanto, Heri [Physic Department, Faculty of Science and Mathematics, Diponegoro University (Indonesia); Suzery, Meiny [Chemistry Department, Faculty of Science and Mathematics, Diponegoro University (Indonesia)

    2015-12-29

    Microalgae Spirulina sp has been identified as source of protein and other high added value compounds. One of the compounds is phycocyanin as also known for antioxidant use. The extraction of this compound by using conventional method (soxhlet extraction) resulted low yield and longer processing time. This research was aimed to extract phycocyanin by using an extraction assisted by ultrasound irradiation. The extraction was performed by using variable of ultrasound frequency and extraction temperature and ethanol was used as a solvent. The result showed that yield of phycocyanin extracted by conventional method was 11.13% while the ultrasound irradiation could increase the yield up to 15.61% at constant frequency of 42 kHz, while the optimum temperature was obtained at 45°C. The analysis of variable interactions showed that both temperature and time has an interaction and temperature was the highest variable in increasing the yield. The conclusion of this research was the ultrasound could improve significantly the efficiency of extraction as well as activity of phycocyanin extracted from microalgae.

  12. Microwave-assisted extraction and mild saponification for determination of organochlorine pesticides in oyster samples.

    Science.gov (United States)

    Carro, N; García, I; Ignacio, M-C; Llompart, M; Yebra, M-C; Mouteira, A

    2002-10-01

    A sample-preparation procedure (extraction and saponification) using microwave energy is proposed for determination of organochlorine pesticides in oyster samples. A Plackett-Burman factorial design has been used to optimize the microwave-assisted extraction and mild saponification on a freeze dried sample spiked with a mixture of aldrin, endrin, dieldrin, heptachlor, heptachorepoxide, isodrin, transnonachlor, p, p'-DDE, and p, p'-DDD. Six variables: solvent volume, extraction time, extraction temperature, amount of acetone (%) in the extractant solvent, amount of sample, and volume of NaOH solution were considered in the optimization process. The results show that the amount of sample is statistically significant for dieldrin, aldrin, p, p'-DDE, heptachlor, and transnonachlor and solvent volume for dieldrin, aldrin, and p, p'-DDE. The volume of NaOH solution is statistically significant for aldrin and p, p'-DDE only. Extraction temperature and extraction time seem to be the main factors determining the efficiency of extraction process for isodrin and p, p'-DDE, respectively. The optimized procedure was compared with conventional Soxhlet extraction.

  13. Optimized Ultrasound-Assisted Extraction of Phenolic Compounds from Polygonum cuspidatum

    Directory of Open Access Journals (Sweden)

    Chia-Hung Kuo

    2013-12-01

    Full Text Available In this study the phenolic compounds piceid, resveratrol and emodin were extracted from P. cuspidatum roots using ultrasound-assisted extraction. Multiple response surface methodology was used to optimize the extraction conditions of these phenolic compounds. A three-factor and three-level Box-Behnken experimental design was employed to evaluate the effects of the operation parameters, including extraction temperature (30–70 °C, ethanol concentration (40%–80%, and ultrasonic power (90–150 W, on the extraction yields of piceid, resveratrol, and emodin. The statistical models built from multiple response surface methodology were developed for the estimation of the extraction yields of multi-phenolic components. Based on the model, the extraction yields of piceid, resveratrol, and emodin can be improved by controlling the extraction parameters. Under the optimum conditions, the extraction yields of piceid, resveratrol and emodin were 10.77 mg/g, 3.82 mg/g and 11.72 mg/g, respectively.

  14. The effects of temperature and frequencies in ultrasound assisted extraction of phycocyanin from microalgae Spirulina sp

    Science.gov (United States)

    Hadiyanto, Suttrisnorhadi, Sutanto, Heri; Suzery, Meiny; Soetrisnanto, Danny; Azizah, Nur

    2015-12-01

    Microalgae Spirulina sp has been identified as source of protein and other high added value compounds. One of the compounds is phycocyanin as also known for antioxidant use. The extraction of this compound by using conventional method (soxhlet extraction) resulted low yield and longer processing time. This research was aimed to extract phycocyanin by using an extraction assisted by ultrasound irradiation. The extraction was performed by using variable of ultrasound frequency and extraction temperature and ethanol was used as a solvent. The result showed that yield of phycocyanin extracted by conventional method was 11.13% while the ultrasound irradiation could increase the yield up to 15.61% at constant frequency of 42 kHz, while the optimum temperature was obtained at 45°C. The analysis of variable interactions showed that both temperature and time has an interaction and temperature was the highest variable in increasing the yield. The conclusion of this research was the ultrasound could improve significantly the efficiency of extraction as well as activity of phycocyanin extracted from microalgae.

  15. MICROWAVE-ASSISTED EXTRACTION OF PHENOLIC COMPOUNDS FROM POLYGONUM MULTIFLORUM THUNB. ROOTS

    Directory of Open Access Journals (Sweden)

    Le Pham Tan Quoc

    2016-06-01

    Full Text Available Background. The aim of this study was to determine the best extraction conditions for total phenolic con- tent (TPC and antioxidant capacity (AC of Polygonum multiflorum Thunb. root using microwave-assisted extraction (MAE. Material and methods. The raw material used was Polygonum multiflorum Thunb. root powder. Five fac- tors such as solvent type, solvent concentrations, solvent/material ratio, extraction time and microwave power were studied; TPC and AC values were determined by the Folin-Ciocalteu method and DPPH free radical scavenging activity measurement, respectively. In addition, studies involved assaying the HPLC test of extracts and SEM of samples. Results. Optimal results pointed to acetone as the solvent, acetone concentration of 60%, solvent/material ratio of 40/1 (v/w, extraction time of 5 mins and microwave power of 127 W. TPC and AC obtained were approximates 44.3 ±0.13 mg GAE/g DW and 341.26 ±1.54 μmol TE/g DW, respectively. The effect of mi- crowaving on the cell destruction of Polygonum multiflorum Thunb. root was observed by scanning electron microscopy (SEM. Some phenolic compounds were determined by the HPLC method, for instance, gallic acid, catechin and resveratrol. Conclusion. These factors significantly affected TPC and AC. We can use acetone as a solvent with micro- wave-assisted extraction to achieve the best result.

  16. Enzyme-assisted supercritical carbon dioxide extraction of black pepper oleoresin for enhanced yield of piperine-rich extract.

    Science.gov (United States)

    Dutta, Sayantani; Bhattacharjee, Paramita

    2015-07-01

    Black pepper (Piper nigrum L.), the King of Spices is the most popular spice globally and its active ingredient, piperine, is reportedly known for its therapeutic potency. In this work, enzyme-assisted supercritical carbon dioxide (SC-CO2) extraction of black pepper oleoresin was investigated using α-amylase (from Bacillus licheniformis) for enhanced yield of piperine-rich extract possessing good combination of phytochemical properties. Optimization of the extraction parameters (without enzyme), mainly temperature and pressure, was conducted in both batch and continuous modes and the optimized conditions that provided the maximum yield of piperine was in the batch mode, with a sample size of 20 g of black pepper powder (particle diameter 0.42 ± 0.02 mm) at 60 °C and 300 bar at 2 L/min of CO2 flow. Studies on activity of α-amylase were conducted under these optimized conditions in both batch and continuous modes, with varying amounts of lyophilized enzyme (2 mg, 5 mg and 10 mg) and time of exposure of the enzyme to SC-CO2 (2.25 h and 4.25 h). The specific activity of the enzyme increased by 2.13 times when treated in the continuous mode than in the batch mode (1.25 times increase). The structural changes of the treated enzymes were studied by (1)H NMR analyses. In case of α-amylase assisted extractions of black pepper, both batch and continuous modes significantly increased the yields and phytochemical properties of piperine-rich extracts; with higher increase in batch mode than in continuous. PMID:25617183

  17. Enzyme-assisted supercritical carbon dioxide extraction of black pepper oleoresin for enhanced yield of piperine-rich extract.

    Science.gov (United States)

    Dutta, Sayantani; Bhattacharjee, Paramita

    2015-07-01

    Black pepper (Piper nigrum L.), the King of Spices is the most popular spice globally and its active ingredient, piperine, is reportedly known for its therapeutic potency. In this work, enzyme-assisted supercritical carbon dioxide (SC-CO2) extraction of black pepper oleoresin was investigated using α-amylase (from Bacillus licheniformis) for enhanced yield of piperine-rich extract possessing good combination of phytochemical properties. Optimization of the extraction parameters (without enzyme), mainly temperature and pressure, was conducted in both batch and continuous modes and the optimized conditions that provided the maximum yield of piperine was in the batch mode, with a sample size of 20 g of black pepper powder (particle diameter 0.42 ± 0.02 mm) at 60 °C and 300 bar at 2 L/min of CO2 flow. Studies on activity of α-amylase were conducted under these optimized conditions in both batch and continuous modes, with varying amounts of lyophilized enzyme (2 mg, 5 mg and 10 mg) and time of exposure of the enzyme to SC-CO2 (2.25 h and 4.25 h). The specific activity of the enzyme increased by 2.13 times when treated in the continuous mode than in the batch mode (1.25 times increase). The structural changes of the treated enzymes were studied by (1)H NMR analyses. In case of α-amylase assisted extractions of black pepper, both batch and continuous modes significantly increased the yields and phytochemical properties of piperine-rich extracts; with higher increase in batch mode than in continuous.

  18. Conventional and ultrasound-assisted extraction of anthocyanins from blackberry and sweet cherry cultivars.

    Science.gov (United States)

    Oancea, Simona; Grosu, Cristian; Ketney, Otto; Stoia, Mihaela

    2013-01-01

    Blackberry and sweet cherry are important plant foods rich in anthocyanins well-known for their pharmacological and antioxidant effects. The aim of the present paper was to comparatively investigate conventional and ultrasound-assisted extraction procedures in order to isolate an enriched crude anthocyanin extract from blackberry (Thornfree cultivar) and sweet cherry (Black Gold cultivar). Hydroethanolic solution and acidified ethanol were used to conventionally extract anthocyanins by a discontinuous process at 4 degreeC for 2/ 24 hours. Added hydrochloric acid in ethanol of different concentrations proved to be more efficient in both type of samples. In the ultrasound-assisted extraction, the highest recovered anthocyanin content in blackberry (107.81 mg 100 g(-1) FM) was obtained with a 10/1 solvent/solid ratio (v/w) at 30 degreeC for 5 minutes, while a 15/1 solvent/solid ratio (v/w) at 30 degreeC for 20 minutes lead to an increased antioxidant capacity as determined by ferric reducing antioxidant power in the extract using 0.1% HCI in 80% ethanol. The optimum conditions obtained for ultrasound-assisted extraction from sweet cherry in 0.1% HCI in 60% ethanol at 30 degree C include a 15/1 solid/solvent ratio (w/v) and 5 minutes for the maximum yield (36.05 mg 100(-1) FM). The final crude anthocyanin extracts may find useful application as dietary supplements, or may be further purified for application as food ingredients. PMID:23878943

  19. Ultrasound assisted extraction in quantifying lutein from chicken liver using high-performance liquid chromatography.

    Science.gov (United States)

    Sun, Ting; Xu, Zhimin; Godber, J Samuel

    2006-01-01

    Four sample preparation methods, (1) solvent (SOL), (2) saponification and solvent (SP), (3) ultrasound assisted solvent (UA), and (4) saponification and ultrasound assisted solvent (SP-UA), were used for quantifying lutein in chicken liver samples by HPLC. The lutein concentrations obtained by using SOL, UA, SP, and SP-UA were significantly different with values from 10.4 microg/g (UA) to undetected (SOL). Efficiency of the four different methods for extracting lutein from high to low were the UA, SP, SP-UA, and SOL method. The measured value of lutein in the liver sample using the UA method was approximately two and three times higher than that obtained from the SP and SP-UA method, respectively. The methods with saponification significantly affected the stabilities of lutein in liver samples. The lutein concentration measured with the solvent only method was either much lower than any of the other extraction methods or undetectable. This indicated that little lutein in those samples was in a form that could be extracted directly by solvent. Compared with the saponification method, the ultrasound assisted solvent method could effectively extract lutein from sample matrix and thus avoid chemical degradation reactions, which would be especially important for complex biological tissue such as liver.

  20. On-line liquid phase micro-extraction based on drop-in-plug sequential injection lab-at-valve platform for metal determination

    International Nuclear Information System (INIS)

    Highlights: ► Drop-in-plug micro-extraction based on SI-LAV platform for metal preconcentration. ► Automatic liquid phase micro-extraction coupled with FAAS. ► Organic solvents with density higher than water are used. ► Lead determination in environmental water and urine samples. -- Abstract: A novel automatic on-line liquid phase micro-extraction method based on drop-in-plug sequential injection lab-at-valve (LAV) platform was proposed for metal preconcentration and determination. A flow-through micro-extraction chamber mounted at the selection valve was adopted without the need of sophisticated lab-on-valve components. Coupled to flame atomic absorption spectrometry (FAAS), the potential of this lab-at-valve scheme is demonstrated for trace lead determination in environmental and biological water samples. A hydrophobic complex of lead with ammonium pyrrolidine dithiocarbamate (APDC) was formed on-line and subsequently extracted into an 80 μL plug of chloroform. The extraction procedure was performed by forming micro-droplets of aqueous phase into the plug of the extractant. All critical parameters that affect the efficiency of the system were studied and optimized. The proposed method offered good performance characteristics and high preconcentration ratios. For 10 mL sample consumption an enhancement factor of 125 was obtained. The detection limit was 1.8 μg L−1 and the precision expressed as relative standard deviation (RSD) at 50.0 μg L−1 of lead was 2.9%. The proposed method was evaluated by analyzing certified reference materials and applied for lead determination in natural waters and urine samples

  1. The Use of Response Surface Methodology to Optimize the Ultrasound-Assisted Extraction of Five Anthraquinones from Rheum palmatum L.

    OpenAIRE

    Xianghua Xia; Geng-Liang Yang; Xin Deng; Kun-Mu Cheng; Wei Li; Jian Liang; Li-Chun Zhao

    2011-01-01

    In this paper, ultrasound-assisted extraction (UAE) was applied to the extraction of anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion) from Rheum palmatum L. The five anthraquinones were quantified and analyzed by high performance liquid chromatography coupled with UV detection (HPLC-UV). The extraction solvent, extraction temperature and extraction time parameters, the three main factors for UAE, were optimized with response surface methodology (RSM) to obtain the highes...

  2. Microwave-Assisted Simultaneous Extraction of Luteolin and Apigenin from Tree Peony Pod and Evaluation of Its Antioxidant Activity

    OpenAIRE

    Hongzheng Wang; Lei Yang; Yuangang Zu; Xiuhua Zhao

    2014-01-01

    An efficient microwave-assisted extraction (MAE) technique was employed in simultaneous extraction of luteolin and apigenin from tree peony pod. The MAE procedure was optimized using response surface methodology (RSM) and compared with other conventional extraction techniques of macerate extraction (ME) and heat reflux extraction (HRE). The optimal conditions of MAE were as follows: employing 70% ethanol volume fraction as solvent, soaking time of 4 h, liquid-solid ratio of 10 (mL/g), microwa...

  3. Optimized microwave-assisted extraction of 6-gingerol from Zingiber officinale Roscoeand evaluation of antioxidant activity in vitro

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2014-06-01

    Full Text Available Background. 6-Gingerol is one of the most pharmacologically active and abundant components in ginger, which has a wide array of biochemical and pharmacologic activities. In recent years, the application of microwave-assisted extraction (MAE for obtaining bioactive compounds from plant materials has shown tremendous research interest and potential. In this study, an efficient microwave-assisted extraction (MAE technique was developed to extract 6-gingerol from ginger. The extraction efficiency of MAE was also compared with conventional extraction techniques. Material and methods. Fresh gingers (Zingiber officinale Rose. were harvested at commercial maturity (originally from Shandong, laiwu, China. In single-factor experiments for the recovery of 6-gingerol, proper ranges of ratio of liquid to solid, ethanol proportion, microwave power, extraction time were determined. Based on the values obtained in single-factor experiments, a Box-Behnken design (BBD was applied to determine the best combination of extraction variables on the yield of 6-gingerol. Results. The optimum extraction conditions were as follows: microwave power 528 W, ratio of liquid to solid 26 mL g1, extraction time 31s and ethanol proportion 78%. Furthermore, more 6-gingerol and total polyphenols contents were extracted by MAE than conventional methods including Maceration (MAC, Stirring Extraction (SE, Heat reflux extraction (HRE, Ultrasound-assisted extraction (UAE, as well as the antioxidant capacity. Conclusion. Microwave-assisted extraction showed obvious advantages in terms of high extraction efficiency and antioxidant activity of extract within shortest extraction time. Scanning electron microscopy (SEM images of ginger powder materials after different extractions were obtained to provide visual evidence of the disruption effect. To our best knowledge, this is the first report about usage of MAE of 6-gingerol extraction from ginger, which could be referenced for the

  4. Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method

    OpenAIRE

    Chang-Liang Jing; Xiao-Fang Dong; Jian-Ming Tong

    2015-01-01

    Ultrasonic-assisted extraction (UAE) was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM), based on a four-factor, five-level central composite design (CCD), was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined b...

  5. Optimization of Ultrasound-Assisted Extraction of Tannin from Cynomorium songaricum

    Directory of Open Access Journals (Sweden)

    Xiaoli Wang

    2015-08-01

    Full Text Available To optimize ultrasound-assisted extraction technology of tannin from the succulent stem of Cynomorium songaricum. The content of tannin in C. songaricum samples of different source was comparatively studied. Extraction rate of tannin as indexes, extraction process was optimized by single factor experiment and L9(34 orthogonal experiment. The best extraction technology for ultrasonic extraction were 75% as the extraction solvent ethanol concentration, 600 w as the ultrasonic power, 1:65 as the solid-liquid ratio, 105 min as the extraction time and extraction 2 times. According to the results of content determination, C. songaricum samples from Guazhou has the highest tannin content than samples from Xinjiang and Inner Mongolia and in the samples of Guazhou which were harvested in April and May has more content than three-nine C. songaricum (harvested in the third nine-day period after the winter solstice. This study could provide scientific basis for rational development and quality control of C. songaricum.

  6. Ultrasound-assisted extraction of polyphenols from Thymus serpyllum and its antioxidant activity

    Directory of Open Access Journals (Sweden)

    Jovanović Aleksandra A.

    2016-01-01

    Full Text Available The present study was designed to establish and optimize a method for extracting natural bioactive compounds from Thymus serpyllum which possess antioxidant, antimicrobial, antispasmotic and stimulant properties. Ultrasound-assisted extraction (UAE is a well-established method in the processing of plant material, particularly for extraction of bioactive substances such as polyphenols. The influential factors including extraction time (3, 7 and 10 minutes, solid:solvent ratio (1:10, 1:20 and 1:30 and particle size (0.3, 0.7 and 1.5 mm, have been studied to optimize the extraction process, while using 30% ethanol as an extraction medium and amplitude set to 65%. The yield of UAE was expressed via total phenol content and antioxidant activity of the obtained extracts. The optimum process paremeters were found to be: extraction time, 3 min; solid:solvent ratio, 1:30; particle size, 0.3 mm. Under these conditions, the yield of total polyphenols was raised up to 23.03 mg/L GA and the highest antioxidant activity was recorded (10.32 mmol/mg Trolox and IC50 3.00 mg/ml. [Projekat Ministarstva nauke Republike Srbije, br. 46010 i br. 46013

  7. Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds

    Institute of Scientific and Technical Information of China (English)

    JING Li-jia; LI Si-yang; CHANG Zui; WANG Yang; YAN Xiu-feng

    2011-01-01

    Naturally occurring camptothecin (CPT) is an important source of chemotherapeutic agents. The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis. In the present study, ultrasound-assisted extractions (UAE) of CPT from C. acuminata seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid Chromatography. The conditions of alkaline species and concentrations, extraction time, extraction temperature and ultrasonic power were optimized.Results show that both Na3PO4 and Na2CO3 solutions gain good extraction yields, whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does, thus aqueous Na2CO3 is more beneficial for the extraction. The optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50℃ and ultrasonic power of 400 W for 60 min. Comparing with UAE with ethanol, the extraction with 0.5% Na2CO3 solution achieves higher yield. Moreover, aqueous Na2CO3 as a solvent has various advantages including non-toxicity, inflammable, non-corrosive and low cost, which ensure this UAE method is a superior method with high utilizing prospect.

  8. Cellulase-assisted extraction of polysaccharides from Cucurbita moschata and their antibacterial activity.

    Science.gov (United States)

    Qian, Zhi-Gang

    2014-01-30

    In this study, cellulase-assisted extraction of water soluble polysaccharides from pumpkin (Cucurbita moschata) and their antibacterial activity were investigated. The polysaccharides yield was monitored during the extraction process. The optimum extraction conditions were determined as follows: time, 40 min; temperature, 55°C; pH, 4.5; and cellulase amount, 4,000 U/g. The extracts were centrifuged, filtered, proteins removed by Sevag method, concentrated to approximately 15% (w/v), precipitated with 5 volumes of absolute ethanol, freeze-dried, and pulverized to yield a water soluble powder of pumpkin polysaccharides (PP). The sugar content of the product was 68.3%, and the yield was 17.34% (w/w), respectively. The PP had high antibacterial activity against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli at the concentration of 100 mg/mL.

  9. Extraction of Angelica sinensis polysaccharides using ultrasound-assisted way and its bioactivity.

    Science.gov (United States)

    Zhao, Ying; Shi, Yongyong; Yang, Huixin; Mao, Lijuan

    2016-07-01

    In the present article, ultrasound-assisted extraction (UAE) of polysaccharides from Angelica sinensis were investigated. The aim of the study is to examine the extraction parameters such as ultrasound power (140-180W), the ratio of liquid to solid (5-7), extraction time (40-50min) and extraction temperature (80-100°C) and to obtain the best possible combinations of these parameters through response surface methodology (RSM). Based on contour plots and variance analysis, optimum operational conditions for maximizing polysaccharides yield were found to be 180w, 7, 45min and 90°C. Under the optimum operating conditions determined, 6.96% polysaccharides were achieved. In addition, the results showed that A. sinensis polysaccharides (ASP) could increase antioxidant enzymes activities and decrease the MDA levels in the skeletal muscle of exhaustive exercise rats. This study provides strong evidence that A. sinensis polysaccharides supplementation possessed protective effects against exhaustive exercise-induced oxidative stress.

  10. Microwave assisted extraction of pectin from waste Citrullus lanatus fruit rinds.

    Science.gov (United States)

    Prakash Maran, J; Sivakumar, V; Thirugnanasambandham, K; Sridhar, R

    2014-01-30

    In this present study, microwave-assisted extraction (MAE) was applied to extraction of pectin from waste Citrullus Lanatus fruit rinds. Extraction parameters which are employed in this study are microwave power (160-480 W), irradiation time (60-180s), pH (1-2) and solid-liquid ratio (1:10-1: 30 g/ml) and they were optimized using a four factor three levels Box-Behnken response surface design (BBD) coupled with desirability function methodology. The results showed that, all the process variables have significant effect on the extraction yield of pectin. Optimum MAE conditions for the highest pectin yield from waste C. Lanatus fruit rinds (25.79%) were obtained with microwave power of 477 W, irradiation time of 128 s, pH of 1.52, solid-liquid ratio of 1:20.3g/ml respectively. Validation experiment results were well agreed with predicted value.

  11. Sequential Extraction Results and Mineralogy of Mine Waste and Stream Sediments Associated With Metal Mines in Vermont, Maine, and New Zealand

    Science.gov (United States)

    Piatak, N.M.; Seal, R.R.; Sanzolone, R.F.; Lamothe, P.J.; Brown, Z.A.; Adams, M.

    2007-01-01

    We report results from sequential extraction experiments and the quantitative mineralogy for samples of stream sediments and mine wastes collected from metal mines. Samples were from the Elizabeth, Ely Copper, and Pike Hill Copper mines in Vermont, the Callahan Mine in Maine, and the Martha Mine in New Zealand. The extraction technique targeted the following operationally defined fractions and solid-phase forms: (1) soluble, adsorbed, and exchangeable fractions; (2) carbonates; (3) organic material; (4) amorphous iron- and aluminum-hydroxides and crystalline manganese-oxides; (5) crystalline iron-oxides; (6) sulfides and selenides; and (7) residual material. For most elements, the sum of an element from all extractions steps correlated well with the original unleached concentration. Also, the quantitative mineralogy of the original material compared to that of the residues from two extraction steps gave insight into the effectiveness of reagents at dissolving targeted phases. The data are presented here with minimal interpretation or discussion and further analyses and interpretation will be presented elsewhere.

  12. Lead isotopes combined with a sequential extraction procedure for source apportionment in the dry deposition of Asian dust and non-Asian dust.

    Science.gov (United States)

    Lee, Pyeong-Koo; Yu, Soonyoung

    2016-03-01

    Lead isotopic compositions were determined in leachates that were generated using sequential extractions of dry deposition samples of Asian dust (AD) and non-Asian dust (NAD) and Chinese desert soils, and used to apportion Pb sources. Results showed significant differences in (206)Pb/(207)Pb and (206)Pb/(204)Pb isotopic compositions in non-residual fractions between the dry deposition samples and the Chinese desert soils while (206)Pb/(207)Pb and (206)Pb/(204)Pb isotopic compositions in residual fraction of the dry deposition of AD and NAD were similar to the mean (206)Pb/(207)Pb and (206)Pb/(204)Pb in residual fraction of the Alashan Plateau soil. These results indicate that the geogenic materials of the dry deposition of AD and NAD were largely influenced by the Alashan Plateau soil, while the secondary sources of the dry deposition were different from those of the Chinese desert soils. In particular, the lead isotopic compositions in non-residual fractions of the dry deposition were homogenous, which implies that the non-residual four fractions (F1 to F4) shared the primary anthropogenic origin. (206)Pb/(207)Pb values and the predominant wind directions in the study area suggested that airborne particulates of heavily industrialized Chinese cities were one of the main Pb sources. Source apportionment calculations showed that the average proportion of anthropogenic Pb in the dry deposition of AD and NAD was 87% and 95% respectively in total Pb extraction, 92% and 97% in non-residual fractions, 15% and 49% in residual fraction. Approximately 81% and 80% of the anthropogenic Pb was contributed by coal combustion in China in the dry deposition of AD and NAD respectively while the remainder was derived from industrial Pb contamination. The research result proposes that sequential extractions with Pb isotope analysis are a useful tool for the discrimination of anthropogenic and geogenic origins in highly contaminated AD and NAD. PMID:26708760

  13. Laminarin from Irish Brown Seaweeds Ascophyllum nodosum and Laminaria hyperborea: Ultrasound Assisted Extraction, Characterization and Bioactivity.

    Science.gov (United States)

    Kadam, Shekhar U; O'Donnell, Colm P; Rai, Dilip K; Hossain, Mohammad B; Burgess, Catherine M; Walsh, Des; Tiwari, Brijesh K

    2015-07-01

    Ultrasound assisted extraction (UAE), purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82% and 6.24% on dry weight basis from A. nodosum and L. hyperborea, respectively. Purification of all extracts was carried out using molecular weight cut off dialysis at 10 kDa. Characterization of the laminarin fraction was carried out using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Antioxidant activity of A. nodosum and L. hyperborea extracts had 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition levels of 93.23% and 87.57%, respectively. Moreover, these extracts have shown inihibition of bacterial growth of Staphylcoccus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium. PMID:26184235

  14. Ultrasound-assisted extraction of volatile compounds from industrial Cannabis sativa L. inflorescences

    Directory of Open Access Journals (Sweden)

    C. Da Porto

    2014-02-01

    Full Text Available Summary. This study investigated the use of ultrasound-assisted extraction (UAE to recovery  volatile compounds from the inflorescences of a fiber type Cannabis sativa L. cultivar. The results show that ultrasonic treatment not longer than 5 min allows to obtain an enhanced concentration of terpenes in comparison with maceration. Instead, an ultrasonic treatment longer than 5 min increased  the concentration of δ-9-tetraidrocannabinol (THC. A preliminary screening of cannabis inflorescences scent was performed by headspace solid-phase microextraction (HS-SPME with gas chromatography-mass spectrometry (GC-MS avoiding the chemical modification and artifact formation that can occur in conventional methods . Industrial relevance. Inflorescences of fiber type Cannabis sativa cultivars are generally considered waste parts for fiber industry, although the inflorescences’ volatiles are pleasant to the human sensory system. Cannabis scent originate from volatile monoterpenes and sesquiterpenes . Traditionally, the recovery of floral fragrances from plants is by water distillation (hydro-distillation or steam distillation to produce essential oils. However, these techniques take at least several hours and require the application of heating, which can produce the degradation of thermo labile compounds present in the starting plant material. Ultrasound-assisted extraction can be use as alternative method to extract aroma compounds from inflorescences of fiber type  Cannabis sativa. The extracts so obtained could be used as ingredients for perfumes (cosmetic industry or flavorings for beverages (food industry.Keywords. Ultrasound; Extraction; Cannabis sativa L.; terpenes; THC; HS-SPME

  15. Laminarin from Irish Brown Seaweeds Ascophyllum nodosum and Laminaria hyperborea: Ultrasound Assisted Extraction, Characterization and Bioactivity.

    Science.gov (United States)

    Kadam, Shekhar U; O'Donnell, Colm P; Rai, Dilip K; Hossain, Mohammad B; Burgess, Catherine M; Walsh, Des; Tiwari, Brijesh K

    2015-07-10

    Ultrasound assisted extraction (UAE), purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82% and 6.24% on dry weight basis from A. nodosum and L. hyperborea, respectively. Purification of all extracts was carried out using molecular weight cut off dialysis at 10 kDa. Characterization of the laminarin fraction was carried out using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Antioxidant activity of A. nodosum and L. hyperborea extracts had 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition levels of 93.23% and 87.57%, respectively. Moreover, these extracts have shown inihibition of bacterial growth of Staphylcoccus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium.

  16. Laminarin from Irish Brown Seaweeds Ascophyllum nodosum and Laminaria hyperborea: Ultrasound Assisted Extraction, Characterization and Bioactivity

    Directory of Open Access Journals (Sweden)

    Shekhar U. Kadam

    2015-07-01

    Full Text Available Ultrasound assisted extraction (UAE, purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82% and 6.24% on dry weight basis from A. nodosum and L. hyperborea, respectively. Purification of all extracts was carried out using molecular weight cut off dialysis at 10 kDa. Characterization of the laminarin fraction was carried out using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Antioxidant activity of A. nodosum and L. hyperborea extracts had 2,2-diphenyl-1-picrylhydrazyl (DPPH inhibition levels of 93.23% and 87.57%, respectively. Moreover, these extracts have shown inihibition of bacterial growth of Staphylcoccus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium.

  17. Evaluation of antioxidant and antimicrobial properties of Manilkara zapota L. (chiku) leaves by sequential soxhlet extraction method

    Institute of Scientific and Technical Information of China (English)

    Mital Kaneria; Sumitra Chanda

    2012-01-01

    Objective: Antioxidant and antimicrobial properties of Manilkara zapota L. (chiku) leaves was studied. Methods: The antioxidant property of different solvent extracts of Manilkara zapota L. leaves was evaluated by DPPH free radical, superoxide anion radical, hydroxyl radical scavenging activity and reducing capacity assessment, while the antimicrobial property was evaluated by agar well diffusion method against some of the tested food borne, spoilage, pathogenic and skin disease causing microorganisms. Results: The DPPH free radical scavenging activity of acetone extract was better than that of standard ascorbic acid and superoxide anion scavenging activity of acetone extract was better than that of standard gallic acid. It showed good reducing capacity assessment also. Maximum phenol content was also present in acetone extract thus supporting the idea that phenolic content and antioxidant activity show a direct correlation. Acetone extract showed significant antimicrobial activity amongst all the different solvent extracts. Conclusion:Result presented here suggest that acetone extract of M. zapota leaves possess strong antioxidant and antimicrobial properties, and it may be considered as an interesting and economic source of antioxidants and antimicrobics for therapeutic or nutraceutical industries and for food manufactures or pharmaceuticals.

  18. An Effective Vacuum Assisted Extraction Method for the Optimization of Labdane Diterpenoids from Andrographis paniculata by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ya-Qi Wang

    2014-12-01

    Full Text Available An effective vacuum assisted extraction (VAE technique was proposed for the first time and applied to extract bioactive components from Andrographis paniculata. The process was carefully optimized by response surface methodology (RSM. Under the optimized experimental conditions, the best results were obtained using a boiling temperature of 65 °C, 50% ethanol concentration, 16 min of extraction time, one extraction cycles and a 12:1 liquid-solid ratio. Compared with conventional ultrasonic assisted extraction and heat reflux extraction, the VAE technique gave shorter extraction times and remarkable higher extraction efficiency, which indicated that a certain degree of vacuum gave the solvent a better penetration of the solvent into the pores and between the matrix particles, and enhanced the process of mass transfer. The present results demonstrated that VAE is an efficient, simple and fast method for extracting bioactive components from A. paniculata, which shows great potential for becoming an alternative technique for industrial scale-up applications.

  19. Ultrasound-assisted extraction of volatile compounds from industrial Cannabis sativa L. inflorescences

    OpenAIRE

    Da Porto, C.; Decorti, D.; A. Natolino

    2014-01-01

    Summary. This study investigated the use of ultrasound-assisted extraction (UAE) to recovery  volatile compounds from the inflorescences of a fiber type Cannabis sativa L. cultivar. The results show that ultrasonic treatment not longer than 5 min allows to obtain an enhanced concentration of terpenes in comparison with maceration. Instead, an ultrasonic treatment longer than 5 min increased  the concentration of δ-9-tetraidrocannabinol (THC). A preliminary screening of cannabis inflorescences...

  20. Enzyme-Assisted Extraction of Polyphenols From Rose (Rosa Damascena Mill.) Petals

    OpenAIRE

    Kalcheva-Karadzhova Krasimira; Shikov Vasil; Mihalev Kiril; Dobrev Georgi; Ludneva Danka; Penov Nikolai

    2014-01-01

    : The efficiency of enzyme-assisted extraction for the recovery of polyphenols from rose (Rosa damascena Mill.) petals was evaluated performing a simplex centroid experimental design for mixture with three components (pectinolytic, cellulolytic and hemicellulolytic preparation). The ternary enzyme combinations leaded to the highest contents of total polyphenols, reaching 43% higher average value as compared to the control (without enzymatic treatment) sample. Enzymatic treatments also enhance...

  1. Optimization of Ultrasound-assisted Extraction of Phenolic Compounds from Myrcia amazonica DC. (Myrtaceae) Leaves

    OpenAIRE

    de Morais Rodrigues, Mariana Cristina; Borges, Leonardo Luiz; Martins, Frederico Severino; Mourão, Rosa Helena V.; da Conceição, Edemilson Cardoso

    2016-01-01

    Background: Myrcia amazonica. DC is a species predominantly found in northern Brazil, and belongs to the Myrtaceae family, which possess various species used in folk medicine to treat gastrointestinal disorders, infectious diseases, and hemorrhagic conditions and are known for their essential oil contents. Materials and Methods: This study aimed applied the Box–Behnken design combined with response surface methodology to optimize ultrasound-assisted extraction of total polyphenols, total tann...

  2. Optimization of ultrasound-assisted extraction of phenolic compounds from Cimicifugae rhizoma with response surface methodology

    OpenAIRE

    Liu, Lin; Shen, Bao-Jia; Xie, Dong-Hao; Cai, Bao-chang; Qin, Kun-Ming; Cai, Hao

    2015-01-01

    Background: Cimicifugae rhizoma was a Ranunculaceae herb belonging to the composite family, and the roots of C. rhizoma have been widely used in tradition Chinese medicine. Materials and Methods: Ultrasound-assisted extraction (UAE) of phenolic compounds from C. rhizoma. Caffeic acid (CA), isoferulic acid (IA), ferulic acid (FA), and total phenols were quantified by high-performance liquid chromatography-diode array detection and ultraviolet-visible spectrophotometer. Effects of several exper...

  3. ULTRASONIC-ASSISTED EXTRACTION OF ANTIOXIDANT PHENOLIC COUMPOUNDS FROM EUCHEUMA COTTONII

    Directory of Open Access Journals (Sweden)

    Dyah Hesti Wardhani

    2014-12-01

    Full Text Available The influences of ultrasonic-assisted extraction (UAE conditions on phenolic compounds of Eucheuma cottonii seaweeed were investigated. The effects of temperature, time and liquid-solid ratio were evaluated based on the total phenolic content (TPC. The result showed a significant variability of effect of temperature, time, and liquid-solid ratio on TPC. Application of ultrasound reduced the optimum temperature, time and liquid-solid ratio of the extraction when compared to the conventional extraction. The highest phenolic content (4.44 mg gallic acid equivalent/g dry weight was obtained at 3:1(v/w of liquid-solid ratio, 55oC of temperature and 35 min of extraction time. At this condition, the extract showed ability to scavenging 91% of 1,1-diphenyl 2 picrylhydrazyl (DPPH radical and 10.9% of H2O2. High ability of the extract to scavenge DPPH radical but low in scavenging H2O2 indicated that the extract dominated by primary antioxidant compounds which work by donating hydrogen atoms to bind free radical.

  4. Comparative study on conventional, ultrasonication and microwave assisted extraction of γ-oryzanol from rice bran.

    Science.gov (United States)

    Kumar, Pramod; Yadav, Devbrat; Kumar, Pradyuman; Panesar, Paramjeet Singh; Bunkar, Durga Shankar; Mishra, Diwaker; Chopra, H K

    2016-04-01

    In present study, conventional, ultrasonic and microwave assisted extraction methods were compared with the aim of optimizing best fitting solvent and method, solvent concentration and digestion time for high yield of γ-oryzanol from rice bran. Petroleum ether, hexane and methanol were used to prepare extracts. Extraction yield were evaluated for giving high crude oil yield, total phenolic content (TPC) and γ-oryzanol content. Gas chromatography-mass spectrophotometry was used for the determination of γ-oryzanol concentration. The highest concentration of γ-oryzanol was detected in methanolic extracts of microwave treatment (85.0 ppm) followed by ultrasonication (82.0 ppm) and conventional extraction method (73.5 ppm). Concentration of γ-oryzanol present in the extracts was found to be directly proportional to the total phenolic content. A combination of 80 % methanolic concentration and 55 minutes digestion time of microwave treatment yielded the best extraction method for TPC and thus γ-oryzanol (105 ppm). PMID:27413233

  5. Dynamic ultrasound-assisted extraction of oleuropein and related biophenols from olive leaves.

    Science.gov (United States)

    Japón-Luján, R; Luque-Rodríguez, J M; Luque de Castro, M D

    2006-03-01

    A continuous approach for the ultrasound-assisted extraction of olive biophenols (OBPs) from olive leaves is proposed. Multivariate methodology was used to carry out a detailed optimisation of extraction. Under the optimal working conditions, complete extraction of the target analytes (namely, oleuropein, verbacoside, apigenin-7-glucoside and luteolin-7-glucoside with LODs 11.04, 2.68, 1.49 and 3.91 mg/kg, respectively) was achieved in 25 min. The extract was injected into a chromatograph-photodiode array detector assembly (HPLC-DAD) for individual separation-quantification. No clean-up or preconcentration steps were required. Gas chromatography-mass spectrometry (without derivatization of the analytes) was used to identify OBPs at concentrations below the LODs obtained by HPLC-DAD. The efficacy of ethanol-water mixtures to extract OBPs from olive leaves has been demonstrated and compared with that of a conventional method which requires 24h for complete extraction; so these mixtures can substitute toxic extractants used to date. PMID:16442552

  6. Stable Isotope-Assisted Evaluation of Different Extraction Solvents for Untargeted Metabolomics of Plants

    Science.gov (United States)

    Doppler, Maria; Kluger, Bernhard; Bueschl, Christoph; Schneider, Christina; Krska, Rudolf; Delcambre, Sylvie; Hiller, Karsten; Lemmens, Marc; Schuhmacher, Rainer

    2016-01-01

    The evaluation of extraction protocols for untargeted metabolomics approaches is still difficult. We have applied a novel stable isotope-assisted workflow for untargeted LC-HRMS-based plant metabolomics , which allows for the first time every detected feature to be considered for method evaluation. The efficiency and complementarity of commonly used extraction solvents, namely 1 + 3 (v/v) mixtures of water and selected organic solvents (methanol, acetonitrile or methanol/acetonitrile 1 + 1 (v/v)), with and without the addition of 0.1% (v/v) formic acid were compared. Four different wheat organs were sampled, extracted and analysed by LC-HRMS. Data evaluation was performed with the in-house-developed MetExtract II software and R. With all tested solvents a total of 871 metabolites were extracted in ear, 785 in stem, 733 in leaf and 517 in root samples, respectively. Between 48% (stem) and 57% (ear) of the metabolites detected in a particular organ were found with all extraction mixtures, and 127 of 996 metabolites were consistently shared between all extraction agent/organ combinations. In aqueous methanol, acidification with formic acid led to pronounced pH dependency regarding the precision of metabolite abundance and the number of detectable metabolites, whereas extracts of acetonitrile-containing mixtures were less affected. Moreover, methanol and acetonitrile have been found to be complementary with respect to extraction efficiency. Interestingly, the beneficial properties of both solvents can be combined by the use of a water-methanol-acetonitrile mixture for global metabolite extraction instead of aqueous methanol or aqueous acetonitrile alone. PMID:27367667

  7. Enzyme-assisted extraction of flavorings and colorants from plant materials.

    Science.gov (United States)

    Sowbhagya, H B; Chitra, V N

    2010-02-01

    From times immemorial, colorants, and flavorings have been used in foods. Color and flavor are the major attributes to the quality of a food product, affecting the appearance and acceptance of the product. As a consequence of the increased demand of natural flavoring and colorant from industries, there is a renewed interest in the research on the composition and recovery of natural food flavors and colors. Over the years, numerous procedures have been proposed for the isolation of aromatic compounds and colors from plant materials. Generally, the methods of extraction followed for aroma and pigment from plant materials are solvent extraction, hydro-distillation, steam distillation, and super critical carbon dioxide extraction. The application of enzymes in the extraction of oil from oil seeds like sunflower, corn, coconut, olives, avocado etc. are reported in literature. There is a great potential for this enzyme-based extraction technology with the selection of appropriate enzymes with optimized operating conditions. Various enzyme combinations are used to loosen the structural integrity of botanical material thereby enhancing the extraction of the desired flavor and color components. Recently enzymes have been used for the extraction of flavor and color from plant materials, as a pre-treatment of the raw material before subjecting the plant material to hydro distillation/solvent extraction. A deep knowledge of enzymes, their mode of action, conditions for optimum activity, and selection of the right type of enzymes are essential to use them effectively for extraction. Although the enzyme hydrolases such as lipases, proteases (chymotrypsin, subtilisin, thermolysin, and papain), esterases use water as a substrate for the reaction, they are also able to accept other nucleophiles such as alcohols, amines, thio-esters, and oximes. Advantages of enzyme-assisted extraction of flavor and color in some of the plant materials in comparison with conventional methods are

  8. Stable Isotope-Assisted Evaluation of Different Extraction Solvents for Untargeted Metabolomics of Plants

    Directory of Open Access Journals (Sweden)

    Maria Doppler

    2016-06-01

    Full Text Available The evaluation of extraction protocols for untargeted metabolomics approaches is still difficult. We have applied a novel stable isotope-assisted workflow for untargeted LC-HRMS-based plant metabolomics , which allows for the first time every detected feature to be considered for method evaluation. The efficiency and complementarity of commonly used extraction solvents, namely 1 + 3 (v/v mixtures of water and selected organic solvents (methanol, acetonitrile or methanol/acetonitrile 1 + 1 (v/v, with and without the addition of 0.1% (v/v formic acid were compared. Four different wheat organs were sampled, extracted and analysed by LC-HRMS. Data evaluation was performed with the in-house-developed MetExtract II software and R. With all tested solvents a total of 871 metabolites were extracted in ear, 785 in stem, 733 in leaf and 517 in root samples, respectively. Between 48% (stem and 57% (ear of the metabolites detected in a particular organ were found with all extraction mixtures, and 127 of 996 metabolites were consistently shared between all extraction agent/organ combinations. In aqueous methanol, acidification with formic acid led to pronounced pH dependency regarding the precision of metabolite abundance and the number of detectable metabolites, whereas extracts of acetonitrile-containing mixtures were less affected. Moreover, methanol and acetonitrile have been found to be complementary with respect to extraction efficiency. Interestingly, the beneficial properties of both solvents can be combined by the use of a water-methanol-acetonitrile mixture for global metabolite extraction instead of aqueous methanol or aqueous acetonitrile alone.

  9. Arsenic fractionation in agricultural soil using an automated three-step sequential extraction method coupled to hydride generation-atomic fluorescence spectrometry

    International Nuclear Information System (INIS)

    Highlights: • A fully automated flow-based modified-BCR extraction method was developed to evaluate the extractable As of soil. • The MSFIA–HG-AFS system included an UV photo-oxidation step for organic species degradation. • The accuracy and precision of the proposed method were found satisfactory. • The time analysis can be reduced up to eight times by using the proposed flow-based BCR method. • The labile As (F1 + F2) was <50% of total As in soil samples from As-contaminated-mining zones. - Abstract: A fully automated modified three-step BCR flow-through sequential extraction method was developed for the fractionation of the arsenic (As) content from agricultural soil based on a multi-syringe flow injection analysis (MSFIA) system coupled to hydride generation-atomic fluorescence spectrometry (HG-AFS). Critical parameters that affect the performance of the automated system were optimized by exploiting a multivariate approach using a Doehlert design. The validation of the flow-based modified-BCR method was carried out by comparison with the conventional BCR method. Thus, the total As content was determined in the following three fractions: fraction 1 (F1), the acid-soluble or interchangeable fraction; fraction 2 (F2), the reducible fraction; and fraction 3 (F3), the oxidizable fraction. The limits of detection (LOD) were 4.0, 3.4, and 23.6 μg L−1 for F1, F2, and F3, respectively. A wide working concentration range was obtained for the analysis of each fraction, i.e., 0.013–0.800, 0.011–0.900 and 0.079–1.400 mg L−1 for F1, F2, and F3, respectively. The precision of the automated MSFIA–HG-AFS system, expressed as the relative standard deviation (RSD), was evaluated for a 200 μg L−1 As standard solution, and RSD values between 5 and 8% were achieved for the three BCR fractions. The new modified three-step BCR flow-based sequential extraction method was satisfactorily applied for arsenic fractionation in real agricultural soil samples from

  10. Arsenic fractionation in agricultural soil using an automated three-step sequential extraction method coupled to hydride generation-atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rosas-Castor, J.M. [Universidad Autónoma de Nuevo León, UANL, Facultad de Ciencias Químicas, Cd. Universitaria, San Nicolás de los Garza, Nuevo León, C.P. 66451 Nuevo León (Mexico); Group of Analytical Chemistry, Automation and Environment, University of Balearic Islands, Cra. Valldemossa km 7.5, 07122 Palma de Mallorca (Spain); Portugal, L.; Ferrer, L. [Group of Analytical Chemistry, Automation and Environment, University of Balearic Islands, Cra. Valldemossa km 7.5, 07122 Palma de Mallorca (Spain); Guzmán-Mar, J.L.; Hernández-Ramírez, A. [Universidad Autónoma de Nuevo León, UANL, Facultad de Ciencias Químicas, Cd. Universitaria, San Nicolás de los Garza, Nuevo León, C.P. 66451 Nuevo León (Mexico); Cerdà, V. [Group of Analytical Chemistry, Automation and Environment, University of Balearic Islands, Cra. Valldemossa km 7.5, 07122 Palma de Mallorca (Spain); Hinojosa-Reyes, L., E-mail: laura.hinojosary@uanl.edu.mx [Universidad Autónoma de Nuevo León, UANL, Facultad de Ciencias Químicas, Cd. Universitaria, San Nicolás de los Garza, Nuevo León, C.P. 66451 Nuevo León (Mexico)

    2015-05-18

    Highlights: • A fully automated flow-based modified-BCR extraction method was developed to evaluate the extractable As of soil. • The MSFIA–HG-AFS system included an UV photo-oxidation step for organic species degradation. • The accuracy and precision of the proposed method were found satisfactory. • The time analysis can be reduced up to eight times by using the proposed flow-based BCR method. • The labile As (F1 + F2) was <50% of total As in soil samples from As-contaminated-mining zones. - Abstract: A fully automated modified three-step BCR flow-through sequential extraction method was developed for the fractionation of the arsenic (As) content from agricultural soil based on a multi-syringe flow injection analysis (MSFIA) system coupled to hydride generation-atomic fluorescence spectrometry (HG-AFS). Critical parameters that affect the performance of the automated system were optimized by exploiting a multivariate approach using a Doehlert design. The validation of the flow-based modified-BCR method was carried out by comparison with the conventional BCR method. Thus, the total As content was determined in the following three fractions: fraction 1 (F1), the acid-soluble or interchangeable fraction; fraction 2 (F2), the reducible fraction; and fraction 3 (F3), the oxidizable fraction. The limits of detection (LOD) were 4.0, 3.4, and 23.6 μg L{sup −1} for F1, F2, and F3, respectively. A wide working concentration range was obtained for the analysis of each fraction, i.e., 0.013–0.800, 0.011–0.900 and 0.079–1.400 mg L{sup −1} for F1, F2, and F3, respectively. The precision of the automated MSFIA–HG-AFS system, expressed as the relative standard deviation (RSD), was evaluated for a 200 μg L{sup −1} As standard solution, and RSD values between 5 and 8% were achieved for the three BCR fractions. The new modified three-step BCR flow-based sequential extraction method was satisfactorily applied for arsenic fractionation in real agricultural

  11. Rapid Determination of Technetium-99 in Large Volume Seawater Samples Using Sequential Injection Extraction Chromatographic Separation and ICP-MS Measurement

    DEFF Research Database (Denmark)

    Shi, Keliang; Qiao, Jixin; Wu, Wangsuo;

    2012-01-01

    An automated method was developed for rapid determination of 99Tc in large volume seawater samples. The analytical procedure involves preconcentration of technetium with coprecipitation, online separation using extraction chromatography (two TEVA columns) implemented in a sequential injection setup......% depending on the sample volumes, and a detection limit of 7.5 mBq/m3 (or 11.5 pg/m3) for 200 L of seawater was obtained. Compared with the conventional analytical procedure, the developed method significantly reduces analytical time. A batch of samples (n > 4) can be analyzed within 24 h. The method has...... been successfully applied for rapid and automated determination of low level 99Tc in large volume seawater samples. The analytical results of seawater samples collected in Denmark show a good agreement with the values obtained using the conventional method....

  12. Rapid and simultaneous determination of neptunium and plutonium isotopes in environmental samples by extraction chromatography using sequential injection analysis and ICP-MS

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per;

    2010-01-01

    This paper reports an automated analytical method for rapid and simultaneous determination of plutonium isotopes (239Pu and 240Pu) and neptunium (237Np) in environmental samples. An extraction chromatographic column packed with TrisKem TEVA® resin was incorporated in a sequential injection (SI......) system for the isolation of plutonium and neptunium from matrix elements and interfering nuclides. Valence adjustment is a crucial step to ensure the same chemical behavior of plutonium and neptunium onto the TEVA column and consequently to accomplish their simultaneous separation and detection. Distinct...... procedures were investigated and compared for the adjustment of oxidation states of plutonium and neptunium to Pu(IV) and Np(IV), respectively. A two-step protocol using sulfite and concentrated nitric acid as redox reagents was proven to be the most effective method. The analytical results for both...

  13. Sulphur K-edge XANES and acid volatile sulphide analyses of changes in chemical speciation of S and Fe during sequential extraction of trace metals in anoxic sludge from biogas reactors

    OpenAIRE

    Shakeri Yekta, Sepehr; Gustavsson, Jenny; Svensson, Bo H.; Skyllberg, Ulf

    2012-01-01

    The effect of sequential extraction of trace metals on sulphur (S) speciation in anoxic sludge samples from two lab-scale biogas reactors augmented with Fe was investigated. Analyses of sulphur K-edge X-ray absorption near edge structure (S XANES) spectroscopy and acid volatile sulphide (AVS) were conducted on the residues from each step of the sequential extraction. The S speciation in sludge samples after AVS analysis was also determined by S XANES. Sulphur was mainly present as FeS (~60% o...

  14. Application of sequential extraction with supercritical CO{sub 2}, subcritical H{sub 2}O, and an H{sub 2}O/CO{sub 2} mixture for estimation of environmentally mobile heavy metal fractions in sediments

    Energy Technology Data Exchange (ETDEWEB)

    Heltai, G.; Feher, B.; Percsich, K.; Barabas, B.; Fekete, I. [Department of Chemistry and Biochemistry, Szent Istvan University, Goedoelloe (Hungary)

    2002-08-01

    Results from use of a new isolation procedure based on sequential extraction with supercritical CO{sub 2}, subcritical H{sub 2}O, and an H{sub 2}O/CO{sub 2} mixture in the same supercritical fluid extractor have been compared with results from the BCR-recommended three-step sequential extraction procedure. The new procedure gives more detailed information about environmentally mobile fractions (water-soluble, bicarbonate-forming), and in less time (5-6 h), than the BCR procedure. (orig.)

  15. Mobility of arsenic, cadmium and zinc in a multi-element contaminated soil profile assessed by in-situ soil pore water sampling, column leaching and sequential extraction

    Energy Technology Data Exchange (ETDEWEB)

    Beesley, Luke, E-mail: l.beesley@2007.ljmu.ac.u [Faculty of Science, Liverpool John Moores University, Liverpool L3 3AF (United Kingdom); Moreno-Jimenez, Eduardo [Departamento de Quimica Agricola, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Clemente, Rafael [Dep. of Soil and Water Conservation and Organic Waste Management, CEBAS-CSIC, Campus Universitario de Espinardo, PO Box 164, 30100 Espinardo, Murcia (Spain); Lepp, Nicholas; Dickinson, Nicholas [Faculty of Science, Liverpool John Moores University, Liverpool L3 3AF (United Kingdom)

    2010-01-15

    Three methods for predicting element mobility in soils have been applied to an iron-rich soil, contaminated with arsenic, cadmium and zinc. Soils were collected from 0 to 30 cm, 30 to 70 cm and 70 to 100 cm depths in the field and soil pore water was collected at different depths from an adjacent 100 cm deep trench. Sequential extraction and a column leaching test in the laboratory were compared to element concentrations in pore water sampled directly from the field. Arsenic showed low extractability, low leachability and occurred at low concentrations in pore water samples. Cadmium and zinc were more labile and present in higher concentrations in pore water, increasing with soil depth. Pore water sampling gave the best indication of short term element mobility when field conditions were taken into account, but further extraction and leaching procedures produced a fuller picture of element dynamics, revealing highly labile Cd deep in the soil profile. - Mobility of arsenic, cadmium and zinc in a polluted soil can be realistically interpreted by in-situ soil pore water sampling.

  16. Sequential leaching extraction of 239,240Pu, 238Pu, 241Pu and 241Am from a mud sample: An intercomparison study

    International Nuclear Information System (INIS)

    Full text: The determination of the association percentages of transuranics to different sediment phases could define their fate once they have been deposited onto the marine floor and their possible reactivity at the sediment/sea water interphase. Nowadays, there is a wide variety of leaching methods to extract transuranics from the different geochemical compounds conforming the sediments. Nevertheless, a general controversy is extended in the scientific world due to the extreme difficulty in testing their reliability, since the standards of transuranics linked to a certain sedimentary phase are not commercially available. Two mud subsamples taken from a storage container were analysed employing the same sequential extraction method, but with small handling differences.The following fractions were isolated: (1) Readily available (2) Carbonate bound and specifically adsorbed (3) Organically bound (4) Oxide and hydroxides bound and (5) residual. The 239,240Pu, 238Pu and 241Am extracted in each phase were analysed using standard radiochemical procedures. 241Pu was determined by both direct scintillation counting and through the 241Am in-growth up on the old disks containing Plutonium. The procedure for uncertainty calculations has been also included. (author)

  17. Bioavailability of CeO2 and SnO2 nanoparticles evaluated by dietary uptake in the earthworm Eisenia fetida and sequential extraction of soil and feed.

    Science.gov (United States)

    Carbone, Serena; Hertel-Aas, Turid; Joner, Erik J; Oughton, Deborah H

    2016-11-01

    The growing number of nanotechnology products on the market will inevitably lead to the release of engineered nanomaterials with potential risk to humans and environment. This study set out to investigate the exposure of soil biota to engineered nanoparticles (NPs). Cerium dioxide (CeO2 NPs) and tin dioxide nanoparticles (SnO2 NPs) were radiolabelled using neutron activation, and employed to assess the uptake and excretion kinetics in the earthworm Eisenia fetida. Through sequential extraction, NPs bioavailability in two contrasting soils and in earthworm feed was also investigated. Neither CeO2 NPs nor SnO2 NPs bioaccumulated in earthworms, and both were rapidly excreted when worms were transferred to clean soil. Low bioavailability was also indicated by low amounts of NPs recovered during extraction with non-stringent extractants. CeO2 NPs showed increasing mobility in organic soil over time (28 days), indicating that organic matter has a strong influence on the fate of CeO2 NPs in soil. PMID:27474912

  18. Neuroprotective Effect of Total and Sequential Extract of Scrophularia striata Boiss. in Rat Cerebellar Granule Neurons Following Glutamate- Induced Neurotoxicity: An In-vitro Study

    Science.gov (United States)

    Salavati, Parvin; Ramezani, Mina; Monsef-Esfahani, Hamid R; Hajiagha, Reza; Parsa, Maliheh; Tavajohi, Shoreh; Ostad, Seyed Nasser

    2013-01-01

    Neuroprotective effect of the extract from aerial parts of Scrophularia striata Boiss (Scrophulariaceae) was investigated against glutamate-induced neurotoxicity on cultured rat pups Cerebellar Granule Neurons (CGNs). CGNs from 8 days old Sprague-Dawley rat were prepared and cultured. The experiments were performed after 8 days in culture. The plant was collected from the northeastern part (Ruin region) of Iran and air-dried at room temperature. The total extract was prepared with maceration of prepared powder in ethanol 80% for three times. Sequential extracts were obtained using dried and powdered aerial parts with increasingly polar solvents: petroleum ether, chloroform, ethyl acetate and methanol 80% solution. Cultured cells were exposed to 125 μM of glutamate for 12 h following a 24 h of incubation with test fractions at concentration of 10 mcg/mL. Morphological assay was performed using invert light microscope after fixation and staining with haematoxylin. Neuronal viability was measured using MTT assay. Statistical analysis was done using SPSS software. One way analysis of variance (ANOVA) was performed by Tukey post-hoc test. Values were considered statistically significant when p-value ≤ 0.05. Results of this study showed a significant neuroprotective activity of high polarity methanolic fraction of aerial parts of Scrophularia striata against glutamate-induced neurotoxicity in a dosedependent manner. Treatment with 10 mcg/mL of the fractions showed the best result. PMID:24250613

  19. Comparison between B CR sequential extraction and geo-accumulation method to evaluate metal mobility in sediments of Dongting Lake, Central China

    Institute of Scientific and Technical Information of China (English)

    YAO Zhigang

    2008-01-01

    The form in which a metal exists strongly influences its mobility and thus,the effects on the environment.Operational methods of speciation analysis,such as the use of sequential extraction procedures,are commonly applied.The Dongting Lake,the second largest fresh-water lake in China,contains three China wetlands of international importance,the East Dongting Lake,South Dongting Lake,and West Dongting Lake.In this work,an optimized BCR sequential extraction procedure was used to assess the environmental risk of Cd,Cr,Cu,Ni,Pb and Zn in contaminated sediment of the Dongting Lake.The procedure was evaluated by using a certified reference material,BCR701.The results of the partitioning study indicated that in the lake sediments,more easily mobilized forms(acid exchangeable) were predominant for Cd,particularly in the samples from the East Dongting Lake.In contrast,the largest amount of Pb was associated with the iron and manganese oxide fractions and Cu,Zn,Cr,and Ni analyzed were mainly distributed in residual phase at an average percentage greater than 60% of the total metals.The potential risk to the lake's water contamination was highest in the East Dongting Lake based on the calculated contamination factors.On the other hand,the total metal content was determined as well by inductively coupled plasma and mass spectrometry(ICP-MS)and assessed by using geo-accumulation index.The assessment results using geo-accumulation index were compared with the information on metal speciation.Both were correspondent with each other.

  20. A sequential approach to control gas for the extraction of multi-gassy coal seams from traditional gas well drainage to mining-induced stress relief

    International Nuclear Information System (INIS)

    Highlights: • The gas reservoirs characteristics are measured and analyzed. • A sequential approach to control gas of multi-gassy coal seams is proposed. • The design of gas drainage wells has been improved. • The utilization ways of different concentrations of gas production are shown. - Abstract: As coal resources become exhausted in shallow mines, mining operations will inevitably progress from shallow depth to deep and gassy seams due to increased demands for more coal products. However, during the extraction process of deeper and gassier coal seams, new challenges to current gas control methods have emerged, these include the conflict between the coal mine safety and the economic benefits, the difficulties in reservoirs improvement, as well as the imbalance between pre-gas drainage, roadway development and coal mining. To solve these problems, a sequential approach is introduced in this paper. Three fundamental principles are proposed: the mining-induced stress relief effect of the first-mined coalbed should be sufficient to improve the permeability of the others; the coal resource of the first-mined seams must be abundant to guarantee the economic benefits; the arrangement of the vertical wells must fit the underground mining panel. Tunlan coal mine is taken as a typical example to demonstrate the effectiveness of this approach. The approach of integrating surface coalbed methane (CBM) exploitation with underground gas control technologies brings three major benefits: the improvement of underground coal mining safety, the implementation of CBM extraction, and the reduction of greenhouse gas emissions. This practice could be used as a valuable example for other coal mines having similar geological conditions

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

    Directory of Open Access Journals (Sweden)

    Xiaolin Wu

    Full Text Available 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.

  2. Response Surface Optimized Ultrasonic-Assisted Extraction of Flavonoids from Sparganii Rhizoma and Evaluation of Their in Vitro Antioxidant Activities

    OpenAIRE

    Wei Yue; Qiaoli Liang; Qinan Wu; Yanfang Wu; Guangyun Chen; Xinsheng Wang

    2012-01-01

    An efficient ultrasound-assisted extraction technique was employed to extract total flavonoids from Sparganii rhizoma. The optimum extraction conditions for the highest yield of total flavonoids were ethanol concentration 53.62%, ultrasonication time 29.41 min and ultrasound power 300 W, which were determined using response surface methodology. The extraction yields of the optimal ultrasound-assisted extraction were higher than using conventional extraction. The crude extract was then purifie...

  3. The mechanism of lipids extraction from wet microalgae Scenedesmus sp. by ionic liquid assisted subcritical water

    Science.gov (United States)

    Yu, Zhuanni; Chen, Xiaolin; Xia, Shuwei

    2016-06-01

    In this paper, the total sugar concentration, protein concentration, lipid yield and morphology characteristics of the algae residue were determined to explain the mechanism of lipids extraction from wet microalgae Scenedesmus sp. by ionic liquid assisted subcritical water. The results showed similar variation for the sugar, protein and lipid. However, the total sugar was more similar to lipids yield, so the results showed that the reaction between ionic liquid and cellulose and hemicellulose in cell wall was the most important step which determined the lipids extration directly. And the total sugar variation may be representing the lipids yield. For later lipids extraction, we can determine the total sugar concentration to predict the extraction end product.

  4. Biodiesel from wet microalgae: extraction with hexane after the microwave-assisted transesterification of lipids.

    Science.gov (United States)

    Cheng, Jun; Huang, Rui; Li, Tao; Zhou, Junhu; Cen, Kefa

    2014-10-01

    A chloroform-free novel process for the efficient production of biodiesel from wet microalgae is proposed. Crude biodiesel is produced through extraction with hexane after microwave-assisted transesterification (EHMT) of lipids in wet microalgae. Effects of different parameters, including reaction temperature, reaction time, methanol dosage, and catalyst dosage, on fatty acids methyl esters (FAMEs) yield are investigated. The yield of FAME extracted into the hexane from the wet microalgae is increased 6-fold after the transesterification of lipids. The yield of FAME obtained through EHMT of lipids in wet microalgae is comparable to that obtained through direct transesterification of dried microalgae biomass with chloroform; however, FAME content in crude biodiesel obtained through EHMT is 86.74%, while that in crude biodiesel obtained through the chloroform-based process is 75.93%. EHMT ensures that polar pigments present in microalgae are not extracted into crude biodiesel, which leads to a 50% reduction in nitrogen content in crude biodiesel.

  5. Modeling and optimization of ultrasound-assisted extraction of polysaccharide from Cucurbita moschata.

    Science.gov (United States)

    Prakash Maran, J; Mekala, V; Manikandan, S

    2013-02-15

    Polysaccharides from pumpkin were extracted by ultrasound-assisted extraction technology using four factors at five levels central composite rotatable response surface design (CCRD). On using single factor analysis, process variables such as extraction temperature (50-70 °C), power of ultrasound (50-70 W), time (15-25 min) and solid-liquid ratio (1:10-1:20 g/ml) were selected. Experiments were conducted to evaluate the effects of four independent variables on the maximum extraction yield of polysaccharides. From the experimental data, second order polynomial mathematical model were developed with high coefficient of determination values (R(2)>0.96). From response surface plots, temperature and ultrasound power exhibited independent and interactive effects on the extraction yields. Extraction temperature of 70 °C, ultrasound power of 70 W, time of 23 min and solid-liquid ratio of 1:10 g/ml were determined as optimal conditions with a maximum polysaccharides yield of 16.21%, which was confirmed through the validation of the experiments.

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

    Science.gov (United States)

    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.

  7. Extraction of Oil from Flaxseed (Linum usitatissimum L.) Using Enzyme-Assisted Three-Phase Partitioning.

    Science.gov (United States)

    Tan, Zhi-Jian; Yang, Zi-Zhen; Yi, Yong-Jian; Wang, Hong-Ying; Zhou, Wan-Lai; Li, Fen-Fang; Wang, Chao-Yun

    2016-08-01

    In this study, enzyme-assisted three-phase partitioning (EATPP) was used to extract oil from flaxseed. The whole procedure is composed of two parts: the enzymolysis procedure in which the flaxseed was hydrolyzed using an enzyme solution (the influencing parameters such as the type and concentration of enzyme, temperature, and pH were optimized) and three-phase partitioning (TPP), which was conducted by adding salt and t-butanol to the crude flaxseed slurry, resulting in the extraction of flaxseed oil into alcohol-rich upper phase. The concentration of t-butanol, concentration of salt, and the temperature were optimized to maximize the extraction yield. Under optimized conditions of a 49.29 % t-butanol concentration, 30.43 % ammonium sulfate concentration, and 35 °C extraction temperature, a maximum extraction yield of 71.68 % was obtained. This simple and effective EATPP can be used to achieve high extraction yields and oil quality, and thus, it is potential for large-scale oil production.

  8. Optimization of enzyme-assisted extraction of polysaccharides from alfalfa and its antioxidant activity.

    Science.gov (United States)

    Wang, Shaopu; Dong, Xiaofang; Tong, Jianming

    2013-11-01

    In this present study, an efficient complex enzyme-assisted extraction technology was developed and optimized to extract polysaccharides from alfalfa using four factors at five levels central composite rotatable response surface design (CCRD). The experimental data was fitted to a second order polynomial equation with high coefficient of determination values (R(2)>0.95). The results of statistical analysis showed that the linear and quadratic terms of these four variables had significant effects (Penzyme concentration of 2.5%, 2.0%, 3.0% (weight of alfalfa) of cellulase, papain and pectase, extraction temperature 52.7 °C, extraction pH 3.87, ratio of water to raw material 78.92 mL/g and extraction time 2.73 h. Under the optimal conditions, the experimental extraction yield of alfalfa polysaccharides was 5.05 ± 0.02%, which was well matched with the value (5.09%) predicted by the CCRD model. Moreover, evaluation of the antioxidant activity of polysaccharides from alfalfa in vitro suggested that the polysaccharides had good antioxidant effect, especially scavenging activity for hydroxyl radical and DPPH radical, which indicated that the polysaccharides from alfalfa may be explored as a novel natural antioxidant.

  9. Ultrasound-assisted extraction, HPLC analysis, and antioxidant activity of polyphenols from unripe apple.

    Science.gov (United States)

    Yue, Tianli; Shao, Dongyan; Yuan, Yahong; Wang, Zhouli; Qiang, Chunyan

    2012-08-01

    The polyphenols were extracted from the unripe apple assisted by a highly efficient and simple method of the ultrasound. Response surface methodology was used to investigate the effects of processing parameters, including ultrasound power, extraction time, temperature, and ethanol concentration on total polyphenols yield and polyphenols composition was analyzed by HPLC. Antioxidant activity of the polyphenols was evaluated as 2, 2-diphenyl-1-picrylhydracyl scavenging activity and inhibition activity of lipid peroxidation. The results showed that 10-100 times higher total polyphenols yield was obtained from the unripe apple than those from the reported apple pomace. The optimum extraction conditions were ultrasonic power of 519.39 W, extraction time of 30 min, extraction temperature 50°C, ethanol concentration of 50% gave the total polyphenols yield of 13.26 ± 0.56 mg GAE/g. HPLC analysis indicated that (-)-epicatechin, procyanidin B2, chlorogenic acid, and procyanidin B1 were the predominant polyphenols in unripe apple, which contributed to the higher antioxidant activity to 2, 2-diphenyl-1-picrylhydracyl of unripe apple polyphenols than other apple polyphenols. The extracted polyphenols had higher ability to inhibit lipid peroxidation than butylated hydroxy toluene, which demonstrated that the unripe apple polyphenols have the potential to be used as a substitute of some synthetic antioxidants.

  10. Optimization of ultrasonic-assisted extraction of natural antioxidants from rice bran using response surface methodology.

    Science.gov (United States)

    Tabaraki, Reza; Nateghi, Ashraf

    2011-11-01

    Ultrasonic technology was applied for extraction of polyphenols and antioxidants from the rice bran using ethanol as a food grade solvent. Response surface methodology (RSM) was used to optimize experimental conditions for extraction of polyphenols and antioxidants. Three independent variables such as solvent percentage (%), temperature (°C) and time (min) were studied. Effect of ethanol concentration was found to be significant on all responses. Total phenolic content (TPC) varied from 2.37 to 6.35mg gallic acid equivalent/g of dry sample. Antioxidant activity of the extracts was determined by the ferric reducing antioxidant power (FRAP) assay and scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. FRAP and DPPH values varied from 31.74 to 57.23μmol Fe(2+)/g of dry sample and 16.88% to 55.61% inhibition, respectively. Extraction yields ranged from 11 to 20.2%. Optimal ultrasonic-assisted extraction (UAE) conditions were identified as 65-67% ethanol, 51-54°C, 40-45min. The experimental values agreed with those predicted by SRM models, thus indicating suitability of the model employed and the success of RSM in optimizing the extraction conditions.

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

    Science.gov (United States)

    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. PMID:25256490

  12. Extraction of Oil from Flaxseed (Linum usitatissimum L.) Using Enzyme-Assisted Three-Phase Partitioning.

    Science.gov (United States)

    Tan, Zhi-Jian; Yang, Zi-Zhen; Yi, Yong-Jian; Wang, Hong-Ying; Zhou, Wan-Lai; Li, Fen-Fang; Wang, Chao-Yun

    2016-08-01

    In this study, enzyme-assisted three-phase partitioning (EATPP) was used to extract oil from flaxseed. The whole procedure is composed of two parts: the enzymolysis procedure in which the flaxseed was hydrolyzed using an enzyme solution (the influencing parameters such as the type and concentration of enzyme, temperature, and pH were optimized) and three-phase partitioning (TPP), which was conducted by adding salt and t-butanol to the crude flaxseed slurry, resulting in the extraction of flaxseed oil into alcohol-rich upper phase. The concentration of t-butanol, concentration of salt, and the temperature were optimized to maximize the extraction yield. Under optimized conditions of a 49.29 % t-butanol concentration, 30.43 % ammonium sulfate concentration, and 35 °C extraction temperature, a maximum extraction yield of 71.68 % was obtained. This simple and effective EATPP can be used to achieve high extraction yields and oil quality, and thus, it is potential for large-scale oil production. PMID:27075456

  13. Optimization of Ficus deltoidea Using Ultrasound-Assisted Extraction by Box-Behnken Statistical Design

    Directory of Open Access Journals (Sweden)

    L. J. Ong

    2016-09-01

    Full Text Available In this study, the effect of extraction parameters (ethanol concentration, sonication time, and solvent-to-sample ratio on Ficus deltoidea leaves was investigated using ultrasound-assisted extraction by response surface methodology (RSM. Total phenolic content (TPC of F. deltoidea extracts was identified using Folin-Ciocalteu method and expressed in gallic acid equivalent (GAE per g. Box-Behnken statistical design (BBD was the tool used to find the optimal conditions for maximum TPC. Besides, the extraction yield was measured and stated in percentage. The optimized TPC attained was 455.78 mg GAE/g at 64% ethanol concentration, 10 minutes sonication time, and 20 mL/g solvent-to-sample ratio whereas the greatest extraction yield was 33% with ethanol concentration of 70%, sonication time of 40 minutes, and solvent-to-material ratio at 40 mL/g. The determination coefficient, R2, for TPC indicates that 99.5% capriciousness in the response could be clarified by the ANOVA model and the value of 0.9681 of predicted R2 is in equitable agreement with the 0.9890 of adjusted R2. The present study shows that ethanol water as solvent, a short time of 10 minutes, and adequate solvent-to-sample ratio (20 mL/g are the best conditions for extraction.

  14. Kinetic modeling of the ultrasound-assisted extraction of polyphenols from Picea abies bark.

    Science.gov (United States)

    Lazar, Liliana; Talmaciu, Adina Iulia; Volf, Irina; Popa, Valentin I

    2016-09-01

    In this paper, the kinetics of polyphenols extraction from spruce bark (Picea abies) under ultrasounds action was investigated. Studies were performed in order to express the effect of some specific parameters (as: ultrasounds, surface contact between solvent and solid, extraction time and temperature) on the total phenolic content (TPC). Experiments were performed in the presence and absence of ultrasounds, using different contact surfaces between solvent and solid, for times from 5 to 75min and temperatures of 318, 323 and 333K. All these factors have a positive influence on the process, enhancing the extraction rate by recovering higher amounts of polyphenols. The process takes place in two stages: a fast one in the first 20-30min (first stage), followed by a slow one approaching to an equilibrium concentration after 40min (second stage). In these conditions, the second-order kinetic model was successfully developed for describing the mechanism of ultrasound-assisted extraction of polyphenols from P. abies bark. Based on this model, values of second-order extraction rate constant (k), initial extraction rate (h), saturation concentration (Cs) and activation energy (Ea) could be predicted. Model validation was done by plotting experimental and predicted values of TPC's, revealing a very good correlation between the obtained data (R(2)>0.98). PMID:27150760

  15. Ultrasound-Assisted Extraction of Carnosic Acid and Rosmarinic Acid Using Ionic Liquid Solution from Rosmarinus officinalis

    OpenAIRE

    Chunjian Zhao; Wenjie Wang; Yuangang Zu; Chunhui Ma; Lei Yang; Rongrui Zhang; Ge Zu

    2012-01-01

    Ionic liquid based, ultrasound-assisted extraction was successfully applied to the extraction of phenolcarboxylic acids, carnosic acid and rosmarinic acid, from Rosmarinus officinalis. Eight ionic liquids, with different cations and anions, were investigated in this work and [C8mim]Br was selected as the optimal solvent. Ultrasound extraction parameters, including soaking time, solid–liquid ratio, ultrasound power and time, and the number of extract...

  16. Ultrasound-Assisted Extraction of Arabinogalactan and Dihydroquercetin Simultaneously from Larix gmelinii as a Pretreatment for Pulping and Papermaking

    OpenAIRE

    Ma, Chunhui; YANG, Lei; Li, Wei; Yue, Jinquan; Jian LI; Zu, Yuangang

    2014-01-01

    An ultrasound-assisted extraction (UAE) method using ethanol was applied for extracting arabinogalactan (AG) and dihydroquercetin (DHQ) simultaneously from larch wood, as a pretreatment for pulping and papermaking. The extraction parameters were optimized by a Box-Behnken experimental design with the yields of AG and DHQ as the response values. Under optimum conditions (three extractions, each using 40% ethanol, for 50 min, 200 W ultrasound power and 1∶18 solid-liquid ratio), the yields of AG...

  17. Response Surface Optimization of a Rapid Ultrasound-Assisted Extraction Method for Simultaneous Determination of Tetracycline Antibiotics in Manure

    OpenAIRE

    2015-01-01

    A rapid and cleanup-free ultrasound-assisted extraction method is proposed for the simultaneous extraction of oxytetracycline, tetracycline, chlortetracycline, and doxycycline in manure. The analytes were determined using high-performance liquid chromatography with ultraviolet detector. The influence of several variables on the efficiency of the extraction procedure was investigated by single-factor experiments. The temperature, pH, and amount of extraction solution were selected for optimiza...

  18. Optimization of Ultrasound Assisted Extraction of Antioxidant Compounds from Marjoram (Origanum majorana L.) Using Response Surface Methodology

    OpenAIRE

    Hossain, Mohammad; Brunton, Nigel; Patras, Ankit; Tiwari, Brijesh; O Donnell, C.; Martin-Diana, Ana Belen; Barry-Ryan, Catherine

    2012-01-01

    The present study optimized the ultrasound assisted extraction (UAE) conditions to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)], total phenol content (TP) and content of individual polyphenols of extracts from marjoram. Optimal conditions with regard to amplitude of sonication (24.4–61.0 μm) and extraction temperature (15–35 °C) and extraction time (5–15 min) were identified using response surface methodology (RSM). The results showed that the combined trea...

  19. An Effective Vacuum Assisted Extraction Method for the Optimization of Labdane Diterpenoids from Andrographis paniculata by Response Surface Methodology

    OpenAIRE

    Ya-Qi Wang; Zhen-Feng Wu; Gang Ke; Ming Yang

    2014-01-01

    An effective vacuum assisted extraction (VAE) technique was proposed for the first time and applied to extract bioactive components from Andrographis paniculata. The process was carefully optimized by response surface methodology (RSM). Under the optimized experimental conditions, the best results were obtained using a boiling temperature of 65 °C, 50% ethanol concentration, 16 min of extraction time, one extraction cycles and a 12:1 liquid-solid ratio. Compared with conventional ultrasonic a...

  20. Novel Gas-assisted Three-liquid-phase Extraction System for Simultaneous Separation and Concentration of Anthraquinones in Herbal Extract

    Institute of Scientific and Technical Information of China (English)

    Xingfu Yang; Xiangfeng Liang; Liangrong Yang; Feng Pan; Fuli Deng; Huizhou Liu

    2014-01-01

    abstract Gas-assisted three-liquid-phase extraction (GATE), which has the advantages of both three-liquid-phase extrac-tion and solvent sublation, is a novel separation technique for separation and concentration of two organic com-pounds into different phases in one step. This highly effective and economically applicable method has been developed for separating emodin and rhein from herbal extract. In a GATE system composed of butyl acetate/PEG4000/ammonium sulfate aqueous solution, influence of various parameters including gas flow rate, flotation time, salt concentration, initial volume of PEG and butyl acetate was investigated. Within 50 min of 30 ml·min-1 nitrogen flow, removal ratio of emodin and rhein from aqueous phase could be over 99%and 97%, respectively. Mass fraction of emodin in the BA phase and rhein in the PEG phase could reach 97%and 95%, respectively. It is demonstrated that gas bubbling is effective for partitioning of emodin and rhein into butyl acetate and PEG phase respectively, and dispersed PEG and butyl acetate could be captured from the aqueous solution. Experi-mental results show that GATE could be an effective and economical technology for concentration and separation of co-existed products in medicinal plants.

  1. Supercritical Carbon Dioxide and Microwave-Assisted Extraction of Functional Lipophilic Compounds from Arthrospira platensis

    Directory of Open Access Journals (Sweden)

    Diego A. Esquivel-Hernández

    2016-05-01

    Full Text Available Arthrospira platensis biomass was used in order to obtain functional lipophilic compounds through green extraction technologies such as supercritical carbon dioxide fluid extraction (SFE and microwave-assisted extraction (MAE. The temperature (T factor was evaluated for MAE, while for SFE, pressure (P, temperature (T, and co-solvent (ethanol (CS were evaluated. The maximum extraction yield of the obtained oleoresin was (4.07% ± 0.14% and (4.27% ± 0.10% for SFE and MAE, respectively. Extracts were characterized by gas chromatography mass spectrometry (GC-MS and gas chromatography flame ionization detector (GC-FID. The maximum contents of functional lipophilic compounds in the SFE and MAE extracts were: for carotenoids 283 ± 0.10 μg/g and 629 ± 0.13 μg/g, respectively; for tocopherols 5.01 ± 0.05 μg/g and 2.46 ± 0.09 μg/g, respectively; and for fatty acids 34.76 ± 0.08 mg/g and 15.88 ± 0.06 mg/g, respectively. In conclusion, the SFE process at P 450 bar, T 60 °C and CS 53.33% of CO2 produced the highest yield of tocopherols, carotenoids and fatty acids. The MAE process at 400 W and 50 °C gives the best extracts in terms of tocopherols and carotenoids. For yield and fatty acids, the MAE process at 400 W and 70 °C produced the highest values. Both SFE and MAE showed to be suitable green extraction technologies for obtaining functional lipophilic compounds from Arthrospira platensis.

  2. Supercritical Carbon Dioxide and Microwave-Assisted Extraction of Functional Lipophilic Compounds from Arthrospira platensis

    Science.gov (United States)

    Esquivel-Hernández, Diego A.; López, Víctor H.; Rodríguez-Rodríguez, José; Alemán-Nava, Gibrán S.; Cuéllar-Bermúdez, Sara P.; Rostro-Alanis, Magdalena; Parra-Saldívar, Roberto

    2016-01-01

    Arthrospira platensis biomass was used in order to obtain functional lipophilic compounds through green extraction technologies such as supercritical carbon dioxide fluid extraction (SFE) and microwave-assisted extraction (MAE). The temperature (T) factor was evaluated for MAE, while for SFE, pressure (P), temperature (T), and co-solvent (ethanol) (CS) were evaluated. The maximum extraction yield of the obtained oleoresin was (4.07% ± 0.14%) and (4.27% ± 0.10%) for SFE and MAE, respectively. Extracts were characterized by gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detector (GC-FID). The maximum contents of functional lipophilic compounds in the SFE and MAE extracts were: for carotenoids 283 ± 0.10 μg/g and 629 ± 0.13 μg/g, respectively; for tocopherols 5.01 ± 0.05 μg/g and 2.46 ± 0.09 μg/g, respectively; and for fatty acids 34.76 ± 0.08 mg/g and 15.88 ± 0.06 mg/g, respectively. In conclusion, the SFE process at P 450 bar, T 60 °C and CS 53.33% of CO2 produced the highest yield of tocopherols, carotenoids and fatty acids. The MAE process at 400 W and 50 °C gives the best extracts in terms of tocopherols and carotenoids. For yield and fatty acids, the MAE process at 400 W and 70 °C produced the highest values. Both SFE and MAE showed to be suitable green extraction technologies for obtaining functional lipophilic compounds from Arthrospira platensis. PMID:27164081

  3. Optimization for Ultrasound-assisted Calcium Hydroxide Extraction of Protein from Shrimp Waste using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Xiaopeng Cui

    2014-02-01

    Full Text Available Each year a considerable number of shrimp wastes were discarded. It caused a waste of resources, but also led to environmental pollution. In order to make a reasonable use of shrimp waste, protein was extracted from Vannamei waste by calcium hydroxide and ultrasonic-assisted, then used response surface methodology to optimize experiments to find the optimum extraction method. The optimal condition, predicted protein extraction rate of 37%, was obtained under the optimum conditions of the extraction time of 81 min, the extraction temperature of 60.00°C and the extraction concentration of 0.18 g/g dry matter.

  4. Improving selenium extraction by sequential enzymatic processes for Se-speciation of selenium-enriched Agaricus bisporus

    Energy Technology Data Exchange (ETDEWEB)

    Dernovics, M.; Stefanka, Z.; Fodor, P. [Department of Applied Chemistry, Faculty of Food Science, Szent Istvan University, Budapest (Hungary)

    2002-02-01

    Sample preparation methods based on the use of proteolytic and cell wall digesting enzymes for the speciation analysis of selenized mushroom were investigated. The sample (Agaricus bisporus; 160 {mu}g total Se per g sample) was grown on compost supplemented with selenized yeast. Experiments were carried out to elucidate the possible role of the cell wall digesting enzymes - Lysing enzyme and Driselase - in the improvement of extraction efficiency with and without inhibiting proteolysis during cell wall digestion. A 3-step procedure applying Lysing enzyme and pronase gave the highest extraction efficiency (89%); however, the best species recovery was achieved by a one-step proteolytic procedure. All the procedures of selenium speciation were controlled by independent ICP-AES analysis measuring the total amount of selenium. (orig.)

  5. Sequential diffusion of ammonium and nitrate from soil extracts to a polytetrafluoroethylene trap for 15N determination

    DEFF Research Database (Denmark)

    Sørensen, P.; Jensen, E.S.

    1991-01-01

    with simulated soil extracts obtained using 50 ml of 2 M potassium chloride solution containing 130-mu-g of NH4+-N (2.3 atom% N-15) and 120-mu-g of NO3--N (natural N-15 abundance). No cross-over in the N-15 abundances of NH4+-N and NO3--N was observed, indicating a quantitative diffusion process (72 h, 25......A novel diffusion method was used for preparation of NH4+- and NO3--N samples from soil extracts for N-15 determination. Ammonium, and nitrate following reduction to ammonia, are allowed to diffuse to an acid-wetted glass filter enclosed in polytetrafluoroethylene tape. The method was evaluated...

  6. Dynamic flow-through sequential extraction for assessment of fractional transformation and inter-element associations of arsenic in stabilized soil and sludge

    Energy Technology Data Exchange (ETDEWEB)

    Buanuam, Janya, E-mail: b_janya@hotmail.com [UFZ - Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstrasse 15, 04318 Leipzig (Germany); Wennrich, Rainer [UFZ - Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstrasse 15, 04318 Leipzig (Germany)

    2010-12-15

    A dynamic flow-through extraction system was applied for the first time to ascertain the fractional transformation and inter-element associations of arsenic in stabilized environmental solids, as exemplified by the partitioning of soil and sludge stabilized with three additives, namely MnO{sub 2}, Ca(OH){sub 2} and FeSO{sub 4}. The extraction system used not only gave fractionation data, but also the extraction profiles (extractograms) which were used for investigation of the breaking down of phases, kinetic releasing of As and elemental association between As and inorganic additives. Five geochemical fractions of As were elucidated by accommodation in the flow manifold of a modified Wenzel's sequential extraction scheme, well established for fractionation of arsenic. The results revealed that MnO{sub 2} and FeSO{sub 4} have a slight effect on As phase transformation for soil and sludge samples amended for one week whereas the addition of Ca(OH){sub 2} increases As mobility due to the desorption of As from the solid Fe-oxides phase. The significant change in fractional transformation after 8 weeks of incubation can be seen in MnO{sub 2}-treated soil. There was an increase of 17% in the non-mobilizable As fraction in MnO{sub 2}-treated soil. From extractograms, arsenic in untreated soil was found to be rapidly leached and concurrently released with Fe. This may be evidence that the release of As is dependent on the dissolution of amorphous Fe oxides. In MnO{sub 2}-treated soil, a strong affinity was observed between Mn and As in the amorphous Fe/Al oxides fraction, and this plays an important role in slowing down the kinetics of As releasing.

  7. Extraction, Preconcentration and Isolation of Flavonoids from Apocynum venetum L. Leaves Using Ionic Liquid-Based Ultrasonic-Assisted Extraction Coupled with an Aqueous Biphasic System

    OpenAIRE

    Zhijian Tan; Yongjian Yi; Hongying Wang; Wanlai Zhou; Chaoyun Wang

    2016-01-01

    Background: Ionic liquids (ILs) are considered as green solvents, and widely applied for the extraction of various compounds. Methods: The present research focuses on the extraction of flavonoids from Apocynum venetum L. leaves by ultrasound-assisted extraction (UAE). Several major influencing factors were optimized. Then, an aqueous biphasic system (ABS) was applied for further isolation of flavonoids. Results: The flavonoids were mainly distributed in the top phase, while impurities were ex...

  8. Optimization of enzyme-assisted extraction and characterization of polysaccharides from Hericium erinaceus.

    Science.gov (United States)

    Zhu, Yang; Li, Qian; Mao, Guanghua; Zou, Ye; Feng, Weiwei; Zheng, Daheng; Wang, Wei; Zhou, Lulu; Zhang, Tianxiu; Yang, Jun; Yang, Liuqing; Wu, Xiangyang

    2014-01-30

    The enzyme-assisted extraction (EAE) of polysaccharides from the fruits of Hericium erinaceus was studied. In this study, response surface methodology and the Box-Behnken design based on single-factor and orthogonal experiments were applied to optimize the EAE conditions. The optimal extraction conditions were as follows: a pH of 5.71, a temperature of 52.03°C and a time of 33.79 min. The optimal extraction conditions resulted in the highest H. erinaceus polysaccharides (HEP) yield, with a value 13.46 ± 0.37%, which represented an increase of 67.72% compared to hot water extraction (HWE). The polysaccharides were characterized by FT-IR, SEM, CD, AFM, and GC. The results showed that HEP was composed of mannose, glucose, xylose, and galactose in a molar ratio of 15.16:5.55:4.21:1. The functional groups of the H. erinaceus polysaccharides extracted by HWE and EAE were fundamentally identical but had apparent conformational changes.

  9. Combined effect of ohmic heating and enzyme assisted aqueous extraction process on soy oil recovery.

    Science.gov (United States)

    Pare, Akash; Nema, Anurag; Singh, V K; Mandhyan, B L

    2014-08-01

    This research describes a new technological process for soybean oil extraction. The process deals with the combined effect of ohmic heating and enzyme assisted aqueous oil extraction process (EAEP) on enhancement of oil recovery from soybean seed. The experimental process consisted of following basic steps, namely, dehulling, wet grinding, enzymatic treatment, ohmic heating, aqueous extraction and centrifugation. The effect of ohmic heating parameters namely electric field strength (EFS), end point temperature (EPT) and holding time (HT) on aqueous oil extraction process were investigated. Three levels of electric field strength (i.e. OH600V, OH750V and OH900V), 3 levels of end point temperature (i.e. 70, 80 and 90 °C) and 3 levels of holding time (i.e. 0, 5 and 10 min.) were taken as independent variables using full factorial design. Percentage oil recovery from soybean by EAEP alone and EAEP coupled with ohmic heating were 53.12 % and 56.86 % to 73 % respectively. The maximum oil recovery (73 %) was obtained when the sample was heated and maintained at 90 °C using electric field strength of OH600V for a holding time of 10 min. The free fatty acid (FFA) of the extracted oil (i.e. in range of 0.97 to 1.29 %) was within the acceptable limit of 3 % (oleic acid) and 0.5-3 % prescribed respectively by PFA and BIS.

  10. Oil extraction from sheanut (Vitellaria paradoxa Gaertn C.F.) kernels assisted by microwaves.

    Science.gov (United States)

    Nde, Divine B; Boldor, Dorin; Astete, Carlos; Muley, Pranjali; Xu, Zhimin

    2016-03-01

    Shea butter, is highly solicited in cosmetics, pharmaceuticals, chocolates and biodiesel formulations. Microwave assisted extraction (MAE) of butter from sheanut kernels was carried using the Doehlert's experimental design. Factors studied were microwave heating time, temperature and solvent/solute ratio while the responses were the quantity of oil extracted and the acid number. Second order models were established to describe the influence of experimental parameters on the responses studied. Under optimum MAE conditions of heating time 23 min, temperature 75 °C and solvent/solute ratio 4:1 more than 88 % of the oil with a free fatty acid (FFA) value less than 2, was extracted compared to the 10 h and solvent/solute ratio of 10:1 required for soxhlet extraction. Scanning electron microscopy was used to elucidate the effect of microwave heating on the kernels' microstructure. Substantial reduction in extraction time and volumes of solvent used and oil of suitable quality are the main benefits derived from the MAE process. PMID:27570267

  11. Ionic liquids based simultaneous ultrasonic and microwave assisted extraction of phenolic compounds from burdock leaves

    International Nuclear Information System (INIS)

    The ionic liquids based simultaneous ultrasonic and microwave assisted extraction (IL-UMAE) technique was first proposed and applied to isolate compounds. The ionic liquids comprising a range of four anions, five 1-alkyl-3-methylimidazolium derivatives were designed and prepared. The results suggested that varying the anion and cation both had apparent effects on the extraction of phenolics. The results also showed that irradiation power, time and solid–liquid ratio significantly affected the yields. The yields of caffeic acid and quercetin obtained by IL-UMAE were higher than those by regular UMAE. Compared with conventional heat-reflux extraction (HRE), the proposed approach exhibited higher efficiency (8–17% enhanced) and shorter extraction time (from 5 h to 30 s). The results indicated ILUMAE to be a fast and efficient extraction technique. Moreover, the proposed method was validated by the reproducibility and recovery experiments. The ILUMAE method provided good recoveries (from 96.1% to 105.3%) with RSD lower than 5.2%, which indicated that the proposed method was credible. Based on the designable nature of ionic liquids, and the rapid and highly efficient performance of the proposed approach, ILUMAE provided a new alternative for preparation of various useful substances from solid samples.

  12. Effect of Ultrasonic-Assisted Extraction on Phenolic Content of Avocado

    International Nuclear Information System (INIS)

    This study evaluate the effect of ultrasonic application in the extraction process on total phenolic content (TPC) of Hass avocado (Persea americana Mill) pulp. In this study, the solid/ solvent ratio of 1/30 (wt/ vol) and extraction temperature of 40 degree Celsius gave higher TPC value. This ratio and temperature was applied in the ultrasonic-assisted extraction (UAE) of avocado pulp. This study then compared the TPC obtained from the avocado pulp extract without involving ultrasonic and the TPC obtained from the UAE. Results showed that the TPC value of avocado pulp was significantly higher in the UAE (235.77 mg GAE/ 100g dried sample) compared to the TPC in the non-UAE (166.32 mg GAE/ 100g dried sample). The increase in the TPC was between ∼31 % and ∼41 % when 5 to 20 min of ultra sonication applied in the extraction. Ultra sonication duration of 15 min gave the highest TPC where the value was significantly higher compared to the other duration. (author)

  13. Sequential analysis

    CERN Document Server

    Wald, Abraham

    2013-01-01

    In 1943, while in charge of Columbia University's Statistical Research Group, Abraham Wald devised Sequential Design, an innovative statistical inference system. Because the decision to terminate an experiment is not predetermined, sequential analysis can arrive at a decision much sooner and with substantially fewer observations than equally reliable test procedures based on a predetermined number of observations. The system's immense value was immediately recognized, and its use was restricted to wartime research and procedures. In 1945, it was released to the public and has since revolutio

  14. Using sequential extraction techniques to assess the partitioning of plutonium and neptunium-237 from multiple sources in sediments from the Ob River (Siberia).

    Science.gov (United States)

    Kenna, Timothy C

    2009-07-01

    Sequential extraction techniques have been developed to assess partitioning of anthropogenic radionuclides ((240)Pu, (239)Pu, and (237)Np), originating from a variety of sources, as identified by using bulk sediment isotopic composition. Sediments were leached sequentially with a series of six chemical treatments designed to approximate different environmental processes that may occur or to selectively extract trace metals contained in different solid phases of the sediments (i.e., exchangeable, reducible, carbonate, organic, acid leachable, and refractory). Results indicate the majority of Pu and Np is similarly distributed within many of the extracted fractions, with the largest percentage (66-97%) of both elements being observed in sediments treated with buffered citrate dithionite (CDB), which targets easily reduced constituents such as Mn and Fe hydrous oxides. While these results do indicate an association of Pu and Np with redox sensitive elements, the environmental implications are unclear given that the CDB treatment is more extreme than naturally occurring conditions. Minor amounts of Np partition differently from Pu in sediments. The NH(4)-acetate treatment, which is designed to liberate trace metals that are loosely adsorbed onto the surfaces of sedimentary materials such as hydrated iron oxides and humic substances, or present at exchangeable sites in clay minerals, mobilized approximately 12% of the total Np while Pu levels were below detection. The H(2)O(2) treatment, which is designed to liberate trace metals bound to organic matter, mobilized approximately 8 and approximately 1% of Np and Pu, respectively. These results indicate that a minor portion of the total Np may be affected by environmental conditions that have little or no effect on Pu. Between 7 and 24% of the Pu was observed in treatments designed to liberate Pu and Np that are tightly bound to lithogenic phases or refractory silicates. The (240)Pu/(239)Pu observed in accessible and

  15. Three-way multivariate analysis of metal fractionation results from sediment samples obtained by different sequential extraction procedures and ICP-OES

    International Nuclear Information System (INIS)

    Three typical schemes for metal fractionation were applied to analyse coastal surface sediment samples from Bahia Blanca estuary, where an important industrial emplacement is located. Also, three certified reference materials for total metal concentrations were analysed. The studied metals were cadmium, chromium, copper, lead and zinc because of their hazardous potential and related abundance in the estuary. The concentration of metals was determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). A three-way multivariate analysis was performed in order to obtain a better visualization of the experimental data. The extracted information was used to evaluate the equivalence among the results obtained by the three sequential extraction schemes. The data were analysed by parallel factor analysis (PARAFAC). PARAFAC models with two factors describe appropriately the data sets (explained variance about 54% and core consistency of 100%). The multivariate decomposition showed that the three applied schemes are able to describe equally well the behaviour of the metals in the different sediment fractions

  16. Comparison of first pass bolus AIFs extracted from sequential {sup 18}F-FDG PET and DSC-MRI of mice

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Eleanor, E-mail: ee244@cam.ac.uk [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Sawiak, Stephen J. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Behavioural and Clinical Neuroscience Institute, Department of Experimental Psychology, University of Cambridge, Cambridge, CB2 3EB (United Kingdom); Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom)

    2014-01-11

    Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and {sup 18}F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

  17. Iodine speciation in coastal and inland bathing waters and seaweeds extracts using a sequential injection standard addition flow-batch method.

    Science.gov (United States)

    Santos, Inês C; Mesquita, Raquel B R; Bordalo, Adriano A; Rangel, António O S S

    2015-02-01

    The present work describes the development of a sequential injection standard addition method for iodine speciation in bathing waters and seaweeds extracts without prior sample treatment. Iodine speciation was obtained by assessing the iodide and iodate content, the two inorganic forms of iodine in waters. For the determination of iodide, an iodide ion selective electrode (ISE) was used. The indirect determination of iodate was based on the spectrophotometric determination of nitrite (Griess reaction). For the iodate measurement, a mixing chamber was employed (flow batch approach) to explore the inherent efficient mixing, essential for the indirect determination of iodate. The application of the standard addition method enabled detection limits of 0.14 µM for iodide and 0.02 µM for iodate, together with the direct introduction of the target water samples, coastal and inland bathing waters. The results obtained were in agreement with those obtained by ICP-MS and a colorimetric reference procedure. Recovery tests also confirmed the accuracy of the developed method which was effectively applied to bathing waters and seaweed extracts. PMID:25435219

  18. On-line dynamic extraction and automated determination of readily bioavailable hexavalent chromium in solid substrates using micro-sequential injection bead-injection lab-on-valve hyphenated with electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Long, Xiangbao; Miró, Manuel; Hansen, Elo Harald

    2006-01-01

    A novel and miniaturized micro-sequential injection bead injection lab-on-valve (μSI-BI-LOV) fractionation system was developed for in-line microcolumn soil extraction under simulated environmental scenarios and accurate monitoring of the content of easily mobilisable hexavalent chromium in soil ...

  19. Liquid-liquid extraction separation and sequential determination of plutonium and americium in environmental samples by alpha-spectrometry

    International Nuclear Information System (INIS)

    A procedure is described by which plutonium and americium can be determined in environmental samples. The sample is leached with nitric acid and hydrogen peroxide, and the two elements are co-precipitated with ferric hydroxide and calcium oxalate. The calcium oxalate is incinerated at 4500 and the ash is dissolved in nitric acid. Plutonium is extracted with tri-n-octylamine solution in xylene from 4M nitric acid and stripped with ammonium iodide/hydrochloric acid. Americium is extracted with thenoyltrifluoroacetone solution in xylene at pH 4 together with rare-earth elements and stripped with 1M nitric acid. Americium and the rare-earth elements thus separated are sorbed on Dowex 1 x 4 resin from 1M nitric acid in 93% methanol, the rare-earth elements are eluted with 0.1M hydrochloric acid/0.5M ammonium thiocyanate/80% methanol and the americium is finally eluted with 1.5M hydrochloric acid in 86% methanol. Plutonium and americium in each fraction are electro-deposited and determined by alpha-spectrometry. Overall average recoveries are 81% for plutonium and 59% for americium. (author)

  20. Blotting Assisted by Heating and Solvent Extraction for DESI-MS Imaging

    Science.gov (United States)

    Cabral, Elaine C.; Mirabelli, Mario F.; Perez, Consuelo J.; Ifa, Demian R.

    2013-06-01

    Imprints of potato sprout ( Solanum tuberosum L.), gingko leaves (Gingko biloba L. ) and strawberries (Fragaria x ananassa Duch. ) were successfully imaged by desorption electrospray ionization mass spectrometry (DESI-MS) on TLC plates through blotting assisted by heating and/or solvent extraction. Ion images showing the distribution of significant compounds such as glycoalkaloid toxins in potato sprout, ginkgolic acids and flavonoids in ginkgo leaves, and sugars and anthocyanidin in strawberry were obtained. Practical implications of this work include analysis of a wide range of irregular or soft materials by different imprinting conditions without requiring the addition of matrices or use of specific kinds of surfaces.

  1. Fast environment-friendly ball mill-assisted deep eutectic solvent-based extraction of natural products.

    Science.gov (United States)

    Wang, Man; Wang, Jiaqin; Zhang, Yue; Xia, Qian; Bi, Wentao; Yang, Xiaodi; Chen, David Da Yong

    2016-04-22

    A fast environment-friendly extraction method, ball mill-assisted deep eutectic solvent-based extraction, was used for the extraction of natural products from plants. In this study, tanshinones were selected as target compounds to evaluate the efficiency of the developed extraction method. Under the optimized experimental conditions, cryptotanshinone (0.176mg/g), tanshinone I (0.181mg/g), and tanshinone II A (0.421mg/g) were extracted from Salvia miltiorrhiza Bunge, and the developed method was found to be greener, more efficient, and faster than conventional, environmentally harmful extraction methods such as methanol-based ultrasound-assisted extraction and heat reflux extraction. The analytical performances including recovery, reproducibility (RSD, n=5), correlation of determination (r(2)), and the limit of detection, with the ranges of 96.1-103.9%, 1.6-1.9%, 0.9973-0.9984, and 5-8ng/mL, were respectively obtained. Application of ball mill-assisted deep eutectic solvent-based extraction may fundamentally shape the future development of extraction methods. PMID:27033981

  2. The Use of Response Surface Methodology to Optimize the Ultrasound-Assisted Extraction of Five Anthraquinones from Rheum palmatum L.

    Directory of Open Access Journals (Sweden)

    Xianghua Xia

    2011-07-01

    Full Text Available In this paper, ultrasound-assisted extraction (UAE was applied to the extraction of anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion from Rheum palmatum L. The five anthraquinones were quantified and analyzed by high performance liquid chromatography coupled with UV detection (HPLC-UV. The extraction solvent, extraction temperature and extraction time parameters, the three main factors for UAE, were optimized with response surface methodology (RSM to obtain the highest extraction efficiency. The optimal conditions were the use of 84% methanol as solvent, an extraction time of 33 min and an extraction temperature of 67 °C. Under these optimal conditions, the experimental values agreed closely with the predicted values. The analysis of variance indicated a high goodness of model fit and the success of RSM method for optimizing anthraquinones extraction in Rheum palmatum L.

  3. Ultrasound-Assisted Extraction of Antioxidants in Misai Kucing (Orthosiphon stamineus

    Directory of Open Access Journals (Sweden)

    Swee Kheng Ho

    2014-08-01

    Full Text Available Ultrasound-assisted extraction (UAE with ethanol was used to extract the compounds responsible for the antioxidant activities of Misai Kucing (Orthosiphon stamineus. Response surface methodology (RSM was used to optimize four independent variables: ethanol concentration (%, amplitude (%, duty cycle (W/s and extraction time (min. Antioxidant compounds were determined by total phenolic content and total flavonoid content to be 1.4 g gallic acid equivalent/100 g DW and 45 g catechin equivalent/100 g DW, respectively. Antioxidant activities were evaluated using the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+ radical scavenging capacity assay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH• radical scavenging capacity assay to be 1,961.3 and 2,423.3 µmol Trolox Equivalent Antioxidant Capacity (TEAC/100 g DW, respectively. Based on the optimal conditions, experimental values were reported to be close to the predicted value by RSM modeling (p > 0.05, indicating the suitability of UAE for extracting the antioxidants of Misai Kucing. Rosmarinic acid, kaempferol-rutinoside and sinesetine were identified by high performance liquid chromatography-mass spectrometry.

  4. Ultrasound-assisted extraction method for the simultaneous determination of emerging contaminants in freshwater sediments.

    Science.gov (United States)

    de Sousa, Diana Nara Ribeiro; Grosseli, Guilherme Martins; Mozeto, Antonio Aparecido; Carneiro, Renato Lajarim; Fadini, Pedro Sergio

    2015-10-01

    Sediments are the fate of several emerging organic contaminants, such as pharmaceuticals, personal care products and hormones, and therefore an important subject in environmental monitoring studies. In the present work, a simple and sensitive method was developed, validated and applied for the simultaneous extraction of atenolol, caffeine, carbamazepine, diclofenac, ibuprofen, naproxen, propranolol, triclosan, estrone, 17-β-estradiol and 17-α-ethinylestradiol using ultrasound-assisted extraction from freshwater sediment samples followed by solid-phase extraction clean-up and liquid chromatography with tandem mass spectrometry detection. The solvent type and extraction pH were evaluated to obtain the highest recoveries of the compounds. The best method shows absolute recoveries between 54.0 and 94.4% at 50 ng/g concentration. The method exhibits good precision with relative standard deviation ranging from 1.0-16%. The detection and quantification limits ranged from 0.006-0.067 and 0.016-0.336 ng/g, respectively. The developed method was successfully applied to freshwater sediment samples collected from different sites in Jundiaí River basin of São Paulo State, Brazil. The compounds atenolol, caffeine, propranolol and triclosan were detected in all the sampling sites with concentrations of 13.8, 41.0, 28.5 and 176 ng/g, respectively. PMID:26257164

  5. Detergent assisted lipid extraction from wet yeast biomass for biodiesel: A response surface methodology approach.

    Science.gov (United States)

    Yellapu, Sravan Kumar; Bezawada, Jyothi; Kaur, Rajwinder; Kuttiraja, Mathiazhakan; Tyagi, Rajeshwar D

    2016-10-01

    The lipid extraction from the microbial biomass is a tedious and high cost dependent process. In the present study, detergent assisted lipids extraction from the culture of the yeast Yarrowia lipolytica SKY-7 was carried out. Response surface methodology (RSM) was used to investigate the effect of three principle parameters (N-LS concentration, time and temperature) on microbial lipid extraction efficiency % (w/w). The results obtained by statistical analysis showed that the quadratic model fits in all cases. Maximum lipid recovery of 95.3±0.3% w/w was obtained at the optimum level of process variables [N-LS concentration 24.42mg (equal to 48mgN-LS/g dry biomass), treatment time 8.8min and reaction temperature 30.2°C]. Whereas the conventional chloroform and methanol extraction to achieve total lipid recovery required 12h at 60°C. The study confirmed that oleaginous yeast biomass treatment with N-lauroyl sarcosine would be a promising approach for industrial scale microbial lipid recovery. PMID:27416517

  6. Extraction of Angelica sinensis polysaccharides using ultrasound-assisted way and its bioactivity.

    Science.gov (United States)

    Zhao, Ying; Shi, Yongyong; Yang, Huixin; Mao, Lijuan

    2016-07-01

    In the present article, ultrasound-assisted extraction (UAE) of polysaccharides from Angelica sinensis were investigated. The aim of the study is to examine the extraction parameters such as ultrasound power (140-180W), the ratio of liquid to solid (5-7), extraction time (40-50min) and extraction temperature (80-100°C) and to obtain the best possible combinations of these parameters through response surface methodology (RSM). Based on contour plots and variance analysis, optimum operational conditions for maximizing polysaccharides yield were found to be 180w, 7, 45min and 90°C. Under the optimum operating conditions determined, 6.96% polysaccharides were achieved. In addition, the results showed that A. sinensis polysaccharides (ASP) could increase antioxidant enzymes activities and decrease the MDA levels in the skeletal muscle of exhaustive exercise rats. This study provides strong evidence that A. sinensis polysaccharides supplementation possessed protective effects against exhaustive exercise-induced oxidative stress. PMID:26845475

  7. Enzyme-assisted extraction of anticoagulant polysaccharide from Liparis tessellatus eggs.

    Science.gov (United States)

    Ticar, Bernadeth F; Rohmah, Zuliyati; Ambut, Carmelo V; Choi, Yeung-Joon; Mussatto, Solange I; Choi, Byeong-Dae

    2015-03-01

    This study aimed to recover a heparin-like anticoagulant polysaccharide from Liparis tessellatus eggs (PLE) by using enzyme-assisted extraction technique. Extraction experiments were carried out using three different enzymes (Alcalase®2.4 L, Flavourzyme®500 MG, and Protamex®) under different conditions of temperature (45, 50, and 55°C), pH (6.5, 7.0, and 7.5), incubation time (24, 36, and 48 h), and enzyme to substrate ratio (E/S=0.5, 1.0, and 1.5%, w/w), which were combined according to a D-optimal design. Statistical analysis of extraction results allowed identifying the variables with greater influence on the extraction yield, and selecting the conditions that maximize the PLE extraction. The best extraction results were achieved when using the Protamex® enzyme in an E/S ratio of 1.34% (w/w), pH 6.60, 47.40°C, during 26.50 h. Under these conditions, a polysaccharide yield of 2.10% (w/w) was obtained. Clotting time measurements, activated partial thromboplastin time, and prothrombin time for evaluation of the anticoagulant properties of PLE were determined and showed increasing activities in correlation with the concentrations used. In the final step, the heparin-like nature of PLE was confirmed by digestion with heparinases I, II, and III, which showed ΔDiHS-0S, ΔDiHS-6S, ΔDiHS-diS1, and ΔDiHS-diS2 at compositions of 0.04, 0.03, 0.35, and 0.24 mol/g, respectively.

  8. Kinetics of Ultrasound-Assisted Flavonoid Extraction from Agri-Food Solid Wastes Using Water/Glycerol Mixtures

    OpenAIRE

    Dimitris P. Makris

    2016-01-01

    Red grape pomace (RGP) and onion solid wastes (OSW) were used as raw material to produce flavonoid-enriched extracts, using ultrasound-assisted solid-liquid extraction. The extraction medium used was composed of water and glycerol and under the conditions used the extraction of flavonoids from both materials was shown to obey first-order kinetics. Maximum diffusivities (De) values were 4.01 × 10−11 and 2.35 × 10−11 m2·s−1, for RGP and OSW extraction, respectively, while the corresponding acti...

  9. Kinetics of Ultrasound-Assisted Flavonoid Extraction from Agri-Food Solid Wastes Using Water/Glycerol Mixtures

    Directory of Open Access Journals (Sweden)

    Dimitris P. Makris

    2016-01-01

    Full Text Available Red grape pomace (RGP and onion solid wastes (OSW were used as raw material to produce flavonoid-enriched extracts, using ultrasound-assisted solid-liquid extraction. The extraction medium used was composed of water and glycerol and under the conditions used the extraction of flavonoids from both materials was shown to obey first-order kinetics. Maximum diffusivities (De values were 4.01 × 10−11 and 2.35 × 10−11 m2·s−1, for RGP and OSW extraction, respectively, while the corresponding activation energies (Ea were 14.00 and 15.23 kJ·mol−1.

  10. Determination of endogenous brassinosteroids using sequential magnetic solid phase extraction followed by in situ derivatization/desorption method coupled with liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Ding, Jun; Mao, Li-Jing; Guo, Ning; Yu, Lei; Feng, Yu-Qi

    2016-05-13

    In this study, a sequential magnetic solid phase extraction followed by in situ derivatization/desorption method was proposed for the fast, selective and sensitive determination of brassinosteroids (BRs) in plant tissues. Magnetic sorbent for quick, easy, cheap, effective, rugged and safe method (mQuEChERS) and polymer(4-vinylphenylboronic acid-co-ethylene glycol dimethacrylate) coated Fe3O4@SiO2 (p(4-VPBA-co-EGDMA) coated Fe3O4@SiO2) were prepared and characterized. Using them as sorbents, pigments and hydrophilic interferents were firstly removed from plant extract by mQuEChERS, and then endogenous BRs were selectively enriched by p(4-VPBA-co-EGDMA) coated Fe3O4@SiO2 through boronate affinity interaction. After loading BRs on p(4-VPBA-co-EGDMA) coated Fe3O4@SiO2, instead of directly eluting free BRs, the adsorbed BRs were released by adding 4-(N,N-dimethyamino)phenylboronic acid (4-DMAPBA) solution for in situ derivatizaiton/desorption of BRs based on a transesterification reaction between the boronate moieties of p(4-VPBA-co-EGDMA) coated Fe3O4@SiO2 and 4-DMAPBA, finally the resultant solution was submitted to LC-MS/MS for quantification. The whole procedure of the sequential MSPE could be accomplished within 1h, and the matrix effect to MS signal after the sample pretreatment was estimated to be in the range of 93.0-97.4%. The established method provided broad linear dynamics ranges (1.0-100.0pg/mL) with correlation coefficients (R) >0.9978, substantial sensitivity (limits of detection ranged from 0.27 to 1.29pg/mL), high reproducibility (intra-day and inter-day relative standard deviations (RSDs) less than 14.8%) and satisfactory accuracy (recoveries ranged from 74.0%-116.6%). Furthermore, endogenous BRs were successfully detected in one flower of Brassica napus L. (22.5-542.7pg/g fresh weight) and other plant tissues (13.7-289.8pg/g fresh weight). PMID:27072523

  11. Optimization of ultrasonic-assisted extraction of antioxidant compounds from Guava (Psidium guajava L.) leaves using response surface methodology

    OpenAIRE

    Fansheng Kong; Shujuan Yu; Zeng Feng; Xinlan Wu

    2015-01-01

    Objective: To optimization of extraction of antioxidant compounds from guava (Psidium guajava L.) leaves and showed that the guava leaves are the potential source of antioxidant compounds. Materials and Methods: The bioactive polysaccharide compounds of guava leaves (P. guajava L.) were obtained using ultrasonic assisted extraction. Extraction was carried out according to Box Behnken central composite design, and independent variables were temperature (20–60°C), time (20–40 min) and power (20...

  12. Determination of fructooligosaccharides in burdock using HPLC and microwave-assisted extraction.

    Science.gov (United States)

    Li, Jing; Liu, Xiaomei; Zhou, Bin; Zhao, Jing; Li, Shaoping

    2013-06-19

    The root of burdock ( Arctium lappa L.) is a commonly used vegetable in Asia. Fructooligosaccharides (FOS) are usually considered as its main bioactive components. Thus, quantitative analysis of these components is very important for the quality control of burdock. In this study, an HPLC-ELSD and microwave-assisted extraction method was developed for the simultaneous determination of seven FOS with degrees of polymerization (DP) between 3 and 9, as well as fructose, glucose, and sucrose in burdock from different regions. The separation was performed on a Waters XBridge Amide column (4.6 × 250 mm i.d., 3.5 μm) with gradient elution. All calibration curves for investigated analytes showed good linear regression (r > 0.9990). Their LODs and LOQs were lower than 3.63 and 24.82 μg/mL, respectively. The recoveries ranged from 99.2 to 102.6%. The developed method was successfully applied to determination of ten sugars in burdock from different locations of Asia. The results showed that the contents of FOS in different samples of burdock collected at appropriate times were similar, and the developed HPLC-ELSD with microwave-assisted extraction method is helpful to control the quality of burdock.

  13. Determination of fructooligosaccharides in burdock using HPLC and microwave-assisted extraction.

    Science.gov (United States)

    Li, Jing; Liu, Xiaomei; Zhou, Bin; Zhao, Jing; Li, Shaoping

    2013-06-19

    The root of burdock ( Arctium lappa L.) is a commonly used vegetable in Asia. Fructooligosaccharides (FOS) are usually considered as its main bioactive components. Thus, quantitative analysis of these components is very important for the quality control of burdock. In this study, an HPLC-ELSD and microwave-assisted extraction method was developed for the simultaneous determination of seven FOS with degrees of polymerization (DP) between 3 and 9, as well as fructose, glucose, and sucrose in burdock from different regions. The separation was performed on a Waters XBridge Amide column (4.6 × 250 mm i.d., 3.5 μm) with gradient elution. All calibration curves for investigated analytes showed good linear regression (r > 0.9990). Their LODs and LOQs were lower than 3.63 and 24.82 μg/mL, respectively. The recoveries ranged from 99.2 to 102.6%. The developed method was successfully applied to determination of ten sugars in burdock from different locations of Asia. The results showed that the contents of FOS in different samples of burdock collected at appropriate times were similar, and the developed HPLC-ELSD with microwave-assisted extraction method is helpful to control the quality of burdock. PMID:23745967

  14. Effect of onion extract on corneal haze suppression after air assisted lamellar keratectomy.

    Science.gov (United States)

    Kim, Soohyun; Park, Young Woo; Lee, Euiri; Park, Sang Wan; Park, Sungwon; Noh, Hyunwoo; Kim, Jong Whi; Seong, Je Kyung; Seo, Kangmoon

    2016-03-01

    This study evaluated the effect of onion extract on corneal haze suppression after applying the air assisted lamellar keratectomy. The air assisted lamellar keratectomy was performed on 24 canine eyes. They were treated with an artificial tear (group C), prednisolone acetate (group P), onion extract (group O) and TGF-β1 (group T) three times per day from 7 to 28 days after the surgery. Corneal haze occurred on the all eyes and was observed beginning 7 days after the surgery. The haze was significantly decreased in groups P and O from day 14 compared with the group C using the clinical (group P; P=0.021, group O; P=0.037) and objective evaluation method (group P; P=0.021, group O; P=0.039). In contrast, it was significantly increased in group T from day 14 compared with group C based on the clinical (P=0.002) and objective evaluation method (Phaze development by suppressing the differentiation of fibroblasts into myofibroblasts.

  15. Sequential extraction and compositional analysis of oil-bearing fluid inclusions in reservoir rocks from Kuche Depression, Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The free oils, adsorbed oils and oil-bearing fluid inclusions have been extracted separately and analyzed by GC and GC-MS in reservoir rock samples collected from the Kuche Depression. The results demonstrate that the molecular compositions of oil-bearing fluid inclusions are significantly different from those of the free oils (the current oils). Compared with the current oil, the oil-bearing fluid inclusions are characterized by relatively high values of parameters Pr/nC17and Ph/nC18, low values of Pr/Ph, hopanes/steranes, C30-diahopane/C30-hopane and Ts/Tm, low content of C29Ts terpane and high maturities as indicated by C29 steranes 20S/(20R+20S). In addition, the oil-bearing fluid inclusions correlate very well with the oils in northern and central Tarim Basin, which were derived from Cambrian-Ordovician marine source rocks. The adsorbedoils appear to be an intermediate type between free oils and oil-bearing fluid inclusions. The above analytical data indicate that there are at least two oil-charging episodes for these reservoir rock samples. The early charging oils were derived from Cambrian-Ordovician marine source rocks, and the later charging oils, from Triassic-Jurassic terrestrial source rocks. The primary marine oils were overwhelmingly diluted by the following terrestrial oils.

  16. Multivariate statistical analysis and optimization of ultrasound-assisted extraction of natural pigments from waste red beet stalks.

    Science.gov (United States)

    Maran, J Prakash; Priya, B

    2016-01-01

    In this study, ultrasound-assisted extraction (UAE) of natural pigment extraction from waste red beet stalks were optimized under four factors (extraction temperature, ultrasonic power, extraction time and solid-liquid ratio) by using three level Box-Behnken response surface design. Extraction temperature, ultrasonic power and solid-liquid ratio were significantly influenced the extraction yield of pigments. Extraction temperature of 53 °C, ultrasonic power of 89 w, extraction time of 35 min and SL ratio of 1:19 g/ml was identified as the optimal condition. Under this condition, the actual yield of (betacyanin of 1.28 ± 0.02 and betaxanthin of 5.31 ± 0.09 mg/g) pigments was well correlated with predicted values (betacyanin was 1.29 mg/g and betaxanthin was 5.32 mg/g). PMID:26788000

  17. Understanding the remobilization of copper, zinc, cadmium and lead due to ageing through sequential extraction and isotopic exchangeability.

    Science.gov (United States)

    Kumar, Manish

    2016-06-01

    Artificial infiltration facilities (AIFs) are useful to control urban runoff and regulate combined sewer overflows. Over the years, AIFs accumulate significant amounts of soakaway sediments and organic matter. The prolonged retention of soakaway sediments in AIFs is likely to cause metal remobilization due to ageing processes. The measurement of the individual consequence of ageing demands homogeneity in physical and chemical profiles of samples. This leads to assessment of metal remobilization in a single soil core through solid-phase extractions and isotopic exchangeability (E value). Depth-wise variation in the physicochemical properties and metal content of the underlying soil (below 1 m of AIFs) was created through 2 weeks of continuous leaching with artificial road runoff (ARR). Ten samples obtained from a 50-cm core by sectioning it at 5-cm intervals were subsequently incubated for 18 months. The results suggest that degradation of organic matter and changes in functional groups due to ageing govern metal remobilization. In general, the top segment showed significant alteration due to ageing. Post incubation, Zn increased dramatically in contrast to subdued Cu and Pb levels in exchangeable fractions with concomitant rise in organic-bound fractions. Isotopic exchangeability of Cd and Zn showed pronounced effect of ageing, although the effect of ageing was distinct in chemical partitioning and isotopic exchangeability of metals; a comparative study of short-term versus long-term incubation will benefit assessment of initial dynamics and final equilibrium. Consequently, the outcome from this work is a viable tool in risk prediction related to soakaway sediment accumulation in AIF. PMID:27236447

  18. Comparison of ultrasound-assisted cloud point extraction and ultrasound-assisted dispersive liquid liquid microextraction for copper coupled with spectrophotometric determination

    Science.gov (United States)

    Yang, Shengchun; Fang, Xiang; Duan, Liju; Yang, Shu; Lei, Zirong; Wen, Xiaodong

    2015-09-01

    In this work, ultrasound-assisted cloud point extraction (UA-CPE) and ultrasound-assisted dispersive liquid liquid microextraction (UA-DLLME) were investigated and compared firstly as ultrasound-assisted liquid phase microextraction methods, which were coupled with spectrophotometer for copper preconcentration and detection. Compared to conventional CPE and DLLME, the extraction patterns were changed and improved by the effect of ultrasound. As novel methods, their applications were expanded and the analytical performance of spectrophotometric determination for copper was considerably improved. The influence factors of UA-CPE and UA-DLLME were studied in detail. Under the optimal conditions, the limits of detection (LODs) for copper were 0.7 μg L-1 of UA-CPE and 0.8 μg L-1 of UA-DLLME with sensitivity enhancement factors (EFs) of 17 and 16. The developed methods were applied to the determination of trace copper in real water samples with satisfactory analytical results.

  19. Comparison of ultrasound-assisted cloud point extraction and ultrasound-assisted dispersive liquid liquid microextraction for copper coupled with spectrophotometric determination.

    Science.gov (United States)

    Yang, Shengchun; Fang, Xiang; Duan, Liju; Yang, Shu; Lei, Zirong; Wen, Xiaodong

    2015-09-01

    In this work, ultrasound-assisted cloud point extraction (UA-CPE) and ultrasound-assisted dispersive liquid liquid microextraction (UA-DLLME) were investigated and compared firstly as ultrasound-assisted liquid phase microextraction methods, which were coupled with spectrophotometer for copper preconcentration and detection. Compared to conventional CPE and DLLME, the extraction patterns were changed and improved by the effect of ultrasound. As novel methods, their applications were expanded and the analytical performance of spectrophotometric determination for copper was considerably improved. The influence factors of UA-CPE and UA-DLLME were studied in detail. Under the optimal conditions, the limits of detection (LODs) for copper were 0.7 μg L(-1) of UA-CPE and 0.8 μg L(-1) of UA-DLLME with sensitivity enhancement factors (EFs) of 17 and 16. The developed methods were applied to the determination of trace copper in real water samples with satisfactory analytical results.

  20. Spectrophotometric determination of low levels arsenic species in beverages after ion-pairing vortex-assisted cloud-point extraction with acridine red.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan; Kır, Ufuk

    2016-01-01

    A new, low-cost, micellar-sensitive and selective spectrophotometric method was developed for the determination of inorganic arsenic (As) species in beverage samples. Vortex-assisted cloud-point extraction (VA-CPE) was used for the efficient pre-concentration of As(V) in the selected samples. The method is based on selective and sensitive ion-pairing of As(V) with acridine red (ARH(+)) in the presence of pyrogallol and sequential extraction into the micellar phase of Triton X-45 at pH 6.0. Under the optimised conditions, the calibration curve was highly linear in the range of 0.8-280 µg l(-1) for As(V). The limits of detection and quantification of the method were 0.25 and 0.83 µg l(-1), respectively. The method was successfully applied to the determination of trace As in the pre-treated and digested samples under microwave and ultrasonic power. As(V) and total As levels in the samples were spectrophotometrically determined after pre-concentration with VA-CPE at 494 nm before and after oxidation with acidic KMnO4. The As(III) levels were calculated from the difference between As(V) and total As levels. The accuracy of the method was demonstrated by analysis of two certified reference materials (CRMs) where the measured values for As were statistically within the 95% confidence limit for the certified values.

  1. Study on demetalization of sewage sludge by sequential extraction before liquefaction for the production of cleaner bio-oil and bio-char.

    Science.gov (United States)

    Leng, Lijian; Yuan, Xingzhong; Shao, Jianguang; Huang, Huajun; Wang, Hou; Li, Hui; Chen, Xiaohong; Zeng, Guangming

    2016-01-01

    Demetalization of sewage sludge (SS) by sequential extraction before liquefaction was implemented to produce cleaner bio-char and bio-oil. Demetalization steps 1 and 2 did not cause much organic matter loss on SS, and thus the bio-oil and bio-char yields and the compositions of bio-oils were also not affected significantly. However, the demetalization procedures resulted in the production of cleaner bio-chars and bio-oils. The total concentrations and the acid soluble/exchangeable fraction (F1 fraction, the most toxic heavy metal fraction) of heavy metals (Cu, Cr, Pb, Zn, and Cd) in these products were significantly reduced and the environmental risks of these products were also relived considerably compared with those produced from raw SS, respectively. Additionally, these bio-oils had less heavy fractions. Demetalization processes with removal of F1 and F2 fractions of heavy metals would benefit the production of cleaner bio-char and bio-oil by liquefaction of heavy metal abundant biomass like SS.

  2. Strong Acid Mixture and Sequential Geochemical Arsenic Extractions in Surface Sediments from the Santa Maria La Reforma Coastal Lagoon, Mexico: A Bioavailability Assessment.

    Science.gov (United States)

    Rivera-Hernández, José R; Green-Ruiz, Carlos

    2016-02-01

    Thirty-three sediment samples were collected from the Santa Maria La Reforma coastal lagoon and digested by way of a strong acid mixture and sequential arsenic (As)-extraction method to determine the arsenic (As) content and bioavailability. The As content was determined by atomic fluorescence spectrometry. In addition, grain-size analyses were performed, and organic carbon, carbonate, and iron (Fe) and manganese (Mn) concentrations were determined. Fe and Mn determination was performed by atomic absorption spectroscopy. A Pearson correlation matrix and As enrichment factors were calculated. Sediment concentrations from Santa Maria La Reforma ranged from 3.6 to 25 µg As g(-1) with an average of 13.4 ± 7.6 µg As g(-1). The highest values were observed in the northern (Playa Colorada), north-central (Mocorito River discharge zone), and southern zones ("El Tule" agricultural drain). Most samples were classified as exhibiting no or minor As enrichment and were lower than the threshold effect level (TEL; 7.24 µg g(-1)) for biota (MacDonald et al. in Ecotoxicology 5:253-278, 1996). Low bioavailable As values (<3 %) were measured in the majority of the sediment. The highest As percentages were associated with the oxyhydroxide fraction (F5). The results indicate that As bioavailability is negligible.

  3. Application of Short Sequential Extraction Procedure(SSEP) for the Determination of Zn, Cu, and Cd Contents in Riverbed Sludge in Hejiagou, Harbin, China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A short sequential extraction procedure(SSEP) was applied to the determination of more readily available metal fractions of Zn, Cu, and Cd in the riverbed sludge in Hejiagou, Harbin, China. From the results, a potential order of metal availability in seven sludge samples was proposed: Cd<Cu<Zn, and samples S1,S2, and S4 were used for the determination of total Zn content, and sample S3 used for the determination of total Cu content in the mobile and the mobilizable fractions showed the highest pollution risk. The results with regard to metal mobility in sludge samples were confirmed by the individual and global contamination factors that were calculated from the nonresidual and resi-dual metal contents. The results obtained from metal-release experiments after exposure of sludge to environmental conditions agreed well with those obtained from both SSEP and the individual and global contamination factors, indicating that the maximum metal release could be an additional factor to evaluate the heavy metal availability in contaminated sludge. A substantial time saving was achieved by using the metal-release method in the present study.

  4. Evolution of phosphorus complexation and mineralogy during (hydro)thermal treatments of activated and anaerobically digested sludge: Insights from sequential extraction and P K-edge XANES.

    Science.gov (United States)

    Huang, Rixiang; Tang, Yuanzhi

    2016-09-01

    (Hydro)thermal treatments of sewage sludge is a promising option that can simultaneously target safe waste disposal, energy recovery, and nutrient recovery/recycling. The speciation of phosphorus (P) in sludge is of great relevance to P reclamation/recycling and soil application of sludge-derived products, thus it is critical to understand the effects of different treatment techniques and conditions on P speciation. This study systematically characterized P speciation (i.e. complexation and mineral forms) in chars derived from pyrolysis and hydrothermal carbonization (HTC) of municipal sewage sludges. Combined sequential extraction and P K-edge X-ray absorption near edge structure (XANES) spectroscopy analysis revealed the dependence of P transformation on treatment conditions and metal composition in the feedstocks. Pyrolysis of sludges decreased the relative abundance of phytic acid while increased the abundance of Al-associated P. HTC thoroughly homogenized and exposed P for interaction with various metals/minerals, with the final P speciation closely related to the composition/speciation of metals and their affinities to P. Results from this study revealed the mechanisms of P transformation during (hydro)thermal treatments of sewage sludges, and might be applicable to other biosolids. It also provided fundamental knowledge basis for the design and selection of waste management strategies for better P (re)cycling and reclamation. PMID:27232988

  5. Rapid determination of plutonium isotopes in environmental samples using sequential injection extraction chromatography and detection by inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per; Miró, Manuel

    2009-10-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed by detection of isolated analytes with inductively coupled plasma mass spectrometry (ICP-MS). The method has been devised for the determination of Pu isotopes at environmentally relevant concentrations, whereby it has been successfully applied to the analyses of large volumes/amounts of samples, for example, 100-200 g of soil and sediment, 20 g of seaweed, and 200 L of seawater following analyte preconcentration. The investigation of the separation capability of the assembled SI system revealed that up to 200 g of soil or sediment can be treated using a column containing about 0.70 g of TEVA resin. The analytical results of Pu isotopes in the reference materials showed good agreement with the certified or reference values at the 0.05 significance level. Chemical yields of Pu ranged from 80 to 105%, and the decontamination factors for uranium, thorium, mercury and lead were all above 10(4). The duration of the in-line extraction chromatographic run was <1.5 h, and the proposed setup was able to handle up to 20 samples (14 mL each) in a fully automated mode using a single chromatographic column. The SI manifold is thus suitable for rapid and automated determination of Pu isotopes in environmental risk assessment and emergency preparedness scenarios. PMID:19722516

  6. Optimization of enzyme assisted extraction of Fructus Mori polysaccharides and its activities on antioxidant and alcohol dehydrogenase.

    Science.gov (United States)

    Deng, Qingfang; Zhou, Xin; Chen, Huaguo

    2014-10-13

    In the present study, enzyme assisted extraction of Fructus Mori polysaccharides (FMPS) from F. mori using four kinds of enzymes and three compound enzymes were examined. Research found that glucose oxidase offered a better performance in enhancement of the extraction yields of FMPS, antioxidant and activate alcohol dehydrogenase activities. The glucose oxidase assisted extraction process was further optimized by using response surface method (RSM) to obtain maximum yield of crude FMPS. The results showed that optimized extraction conditions were ratio of enzyme amount 0.40%, enzyme treated time 38 min, treated temperature 58 °C and liquid-solid radio 11.0. Under these conditions, the mean experimental value of extraction yield (16.16 ± 0.14%) corresponded well with the predicted values and increased 160% than none enzyme treated ones. Pharmacological verification tests showed that F. mori crude polysaccharides had good antioxidant and activate alcohol dehydrogenase activities in vitro.

  7. Ultrasonic-Assisted Extraction of Raspberry Seed Oil and Evaluation of Its Physicochemical Properties, Fatty Acid Compositions and Antioxidant Activities.

    Science.gov (United States)

    Teng, Hui; Chen, Lei; Huang, Qun; Wang, Jinli; Lin, Qiyang; Liu, Mingxin; Lee, Won Young; Song, Hongbo

    2016-01-01

    Ultrasonic-assisted extraction was employed for highly efficient separation of aroma oil from raspberry seeds. A central composite design with two variables and five levels was employed and effects of process variables of sonication time and extraction temperature on oil recovery and quality were investigated. Optimal conditions predicted by response surface methodology were sonication time of 37 min and extraction temperature of 54°C. Specifically, ultrasonic-assisted extraction (UAE) was able to provide a higher content of beneficial unsaturated fatty acids, whereas conventional Soxhlet extraction (SE) resulted in a higher amount of saturated fatty acids. Moreover, raspberry seed oil contained abundant amounts of edible linoleic acid and linolenic acid, which suggest raspberry seeds could be valuable edible sources of natural γ-linolenic acid products. In comparison with SE, UAE exerted higher free radical scavenging capacities. In addition, UAE significantly blocked H2O2-induced intracellular reactive oxygen species (ROS) generation. PMID:27120053

  8. Ultrasonic-Assisted Extraction of Raspberry Seed Oil and Evaluation of Its Physicochemical Properties, Fatty Acid Compositions and Antioxidant Activities.

    Directory of Open Access Journals (Sweden)

    Hui Teng

    Full Text Available Ultrasonic-assisted extraction was employed for highly efficient separation of aroma oil from raspberry seeds. A central composite design with two variables and five levels was employed and effects of process variables of sonication time and extraction temperature on oil recovery and quality were investigated. Optimal conditions predicted by response surface methodology were sonication time of 37 min and extraction temperature of 54°C. Specifically, ultrasonic-assisted extraction (UAE was able to provide a higher content of beneficial unsaturated fatty acids, whereas conventional Soxhlet extraction (SE resulted in a higher amount of saturated fatty acids. Moreover, raspberry seed oil contained abundant amounts of edible linoleic acid and linolenic acid, which suggest raspberry seeds could be valuable edible sources of natural γ-linolenic acid products. In comparison with SE, UAE exerted higher free radical scavenging capacities. In addition, UAE significantly blocked H2O2-induced intracellular reactive oxygen species (ROS generation.

  9. Optimization of Ultrasound-assisted extraction of polyphenols, tannins and epigallocatechin gallate from barks of Stryphnodendron adstringens (Mart.) Coville bark extracts

    OpenAIRE

    Sousa, Jordana N.; Nathalia B. Pedroso; Leonardo L. Borges; Gerlon A.; Jose R. Paula; Edemilson C. Conceicao

    2014-01-01

    Background: Stryphnodendron adstringens (Mar.) Coville is a native plant from Brazil, rich in phenolic compounds and used on popular medicine as a wound healing agent, in the treatment of gastric lesions and as antimicrobial. Materials and Methods: Ultrassound-assisted extraction (UAE) was applied to extraction of epigallocatechin gallate (EGCG), total polyphenols (TP) and total tannins (TT) content from barks of Stryphnodendron adstringens (Mar.) Coville. Several operating parameters, namely...

  10. Seaweed hydrocolloid production: an update on enzyme assisted extraction and modification technologies.

    Science.gov (United States)

    Rhein-Knudsen, Nanna; Ale, Marcel Tutor; Meyer, Anne S

    2015-06-01

    Agar, alginate, and carrageenans are high-value seaweed hydrocolloids, which are used as gelation and thickening agents in different food, pharmaceutical, and biotechnological applications. The annual global production of these hydrocolloids has recently reached 100,000 tons with a gross market value just above US$ 1.1 billion. The techno-functional properties of the seaweed polysaccharides depend strictly on their unique structural make-up, notably degree and position of sulfation and presence of anhydro-bridges. Classical extraction techniques include hot alkali treatments, but recent research has shown promising results with enzymes. Current methods mainly involve use of commercially available enzyme mixtures developed for terrestrial plant material processing. Application of seaweed polysaccharide targeted enzymes allows for selective extraction at mild conditions as well as tailor-made modifications of the hydrocolloids to obtain specific functionalities. This review provides an update of the detailed structural features of κ-, ι-, λ-carrageenans, agars, and alginate, and a thorough discussion of enzyme assisted extraction and processing techniques for these hydrocolloids.

  11. Enzyme-assisted extraction for the HPLC determination of aflatoxin M1 in cheese.

    Science.gov (United States)

    Pietri, Amedeo; Fortunati, Paola; Mulazzi, Annalisa; Bertuzzi, Terenzio

    2016-02-01

    The extraction of aflatoxin M1 (AFM1) from cheese is generally carried out using chlorinated organic solvents. In this study, two innovative methods were developed, based on an enzyme-assisted (EA) extraction using proteolytic enzymes (pepsin or pepsin-pancreatin). After purification through an immunoaffinity column, AFM1 is determined by HPLC-FLD. A comparison between the new EA methods and an established chloroform (CH) method was carried out on 24 cheese samples. The results showed that the extraction efficiency of the EA methods was independent of ripening time of cheese, whereas the CH method was not able to fully recover AFM1 from ripened cheeses. The simpler (pepsin) of the two methods has been adopted by our laboratory for routine analysis of AFM1 in cheese. In comparison with the CH method, the pepsin-HCl (P-HCl) method is simpler, avoiding solvent evaporation, dissolution and partition in a separating funnel; moreover, it gives higher recoveries, comparable LOD and LOQ and more accurate results.

  12. Green ultrasound-assisted extraction of anthocyanin and phenolic compounds from purple sweet potato using response surface methodology

    Science.gov (United States)

    Zhu, Zhenzhou; Guan, Qingyan; Guo, Ying; He, Jingren; Liu, Gang; Li, Shuyi; Barba, Francisco J.; Jaffrin, Michel Y.

    2016-01-01

    Response surface methodology was used to optimize experimental conditions for ultrasound-assisted extraction of valuable components (anthocyanins and phenolics) from purple sweet potatoes using water as a solvent. The Box-Behnken design was used for optimizing extraction responses of anthocyanin extraction yield, phenolic extraction yield, and specific energy consumption. Conditions to obtain maximal anthocyanin extraction yield, maximal phenolic extraction yield, and minimal specific energy consumption were different; an overall desirability function was used to search for overall optimal conditions: extraction temperature of 68ºC, ultrasonic treatment time of 52 min, and a liquid/solid ratio of 20. The optimized anthocyanin extraction yield, phenolic extraction yield, and specific energy consumption were 4.91 mg 100 g-1 fresh weight, 3.24 mg g-1 fresh weight, and 2.07 kWh g-1, respectively, with a desirability of 0.99. This study indicates that ultrasound-assisted extraction should contribute to a green process for valorization of purple sweet potatoes.

  13. Comparison of solid phase extraction, saponification and gel permeation chromatography for the clean-up of microwave-assisted biological extracts in the analysis of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Navarro, P; Cortazar, E; Bartolomé, L; Deusto, M; Raposo, J C; Zuloaga, O; Arana, G; Etxebarria, N

    2006-09-22

    The feasibility of different clean-up procedures was studied for the determination of polycyclic aromatic hydrocarbons (PAHs) in biota samples such as oysters, mussels and fish liver. In this sense, once the samples were extracted--essentially with acetone and in a microwave system--and before they could be analysed by gas chromatography-mass spectrometry (GC-MS), three different approaches were studied for the clean-up step: solid phase extraction (SPE), microwave-assisted saponification (MAS) and gel permeation chromatography (GPC). The main aim of this work was to maximise the recoveries of PAHs and to minimise the presence of interfering compounds in the last extract. In the case of SPE, Florisil cartridges of 1, 2 and 5 g, and silica cartridges of 5 g were studied. In that case, and with oysters and mussels, microwave-assisted extraction and 5 g Florisil cartridges provided good results. In addition, the concentrations obtained for Standard Reference Material (SRM) NIST 2977 (mussel tissue) were in good agreement with the certified values. In the case of microwave-assisted saponification, the extracts were not as clean as those obtained with 5 g Florisil and this fact lead to overestimate the concentration of the heaviest PAHs. Finally, the cleanest extracts were obtained by GPC. The method was successfully applied to mussels, oysters and hake liver, and the results obtained for NIST 2977 (mussel tissue) were within the confidence interval of the certified reference material for most of the certified analytes.

  14. Mining Heterogeneous Multidimensional Sequential Patterns

    OpenAIRE

    Egho, Elias; Raïssi, Chedy; Jay, Nicolas; Napoli, Amedeo

    2014-01-01

    All domains of science and technology produce large and heterogeneous data. Although much work has been done in this area, mining such data is still a challenge. No previous research targets the mining of heterogeneous multidimensional sequential data. In this work, we present a new approach to extract heterogeneous multidimensional sequential patterns with different levels of granularity by relying on external taxonomies. We show the efficiency and interest of our approach with the analysis ...

  15. Determination of Oleanolic and Ursolic Acids in Hedyotis diffusa Using Hyphenated Ultrasound-Assisted Supercritical Carbon Dioxide Extraction and Chromatography

    OpenAIRE

    Ming-Chi Wei; Yu-Chiao Yang; Show-Jen Hong

    2015-01-01

    Oleanolic acid (OA) and ursolic acid (UA) were extracted from Hedyotis diffusa using a hyphenated procedure of ultrasound-assisted and supercritical carbon dioxide (HSC–CO2) extraction at different temperatures, pressures, cosolvent percentages, and SC–CO2 flow rates. The results indicated that these parameters significantly affected the extraction yield. The maximal yields of OA (0.917 mg/g of dry plant) and UA (3.540 mg/g of dry plant) were obtained at a dynamic extraction time of 110 min, ...

  16. Closed vessel microwave assisted extraction - An innovative method for determination of trace metals in plant materials

    Science.gov (United States)

    Oeztan, S.; Duering, R.-A.

    2012-04-01

    Determination of metal concentrations in plant samples is important for better understanding of effects of toxic metals that are biologically magnified through the food chain and compose a great danger to all living beings. In recent years the use of microwave assisted extraction for plant samples has shown tremendous research interest which will probably substitute conventional procedures in the future. Generally conventional procedures have disadvantages including consuming of time and solvents. The objective of this study is to investigate and compare a new closed vessel microwave extraction (MAE) method with the combination of EDTA (MAE-EDTA) for the determination of metal contents (Cd, Mn, Pb, Zn) in plant samples (Lolio-Cynosuretum) by ICP-OES. Validation of the method was done by comparison of the results with another MAE procedure (MAE-H) which is applied with the mixture of 69% nitric acid (HNO3) and 30% hydrogen peroxide (H2O2). Moreover, conventional plant extraction (CE) method, for which the dissolution of plant samples were handled in HNO3 after dry ashing at 420° C, was used as a reference method. Approximately 0.5 g of sample was digested in 5 ml HNO3, 3 ml H2O2, and 5 ml deionized H2O for MAE-H and in 8 ml EDTA solution for MAE-EDTA. Certified plant reference materials (CRMs) were used for comparison of recovery rates from different extraction protocols. Thereby, the applicability of both MAE-H and MAE-EDTA procedures could be demonstrated. For 58 plant samples MAE-H showed the same extraction yields as CE in the determination of trace metal contents of the investigated elements in plant samples. MAE-EDTA gave similar values when compared to MAE-H and highly linear relationships were found for determination of Cd, Mn, Pb and Zn amounts. The recoveries for the CRMs were within the range 89.6-115%. Finally, strategic characteristics of MAE-EDTA for determination metal contents (Cd, Mn, Pb, Zn) in plant samples are: (i) applicability to a large set

  17. Extraction of user's navigation commands from upper body force interaction in walker assisted gait

    Directory of Open Access Journals (Sweden)

    Pons José L

    2010-08-01

    Full Text Available Abstract Background The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. Results For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 ± 0.358·10-2 kgf and delay ((1.897 ± 0.3697·101ms. A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. Conclusions The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.

  18. Microwave- and ultrasound-assisted extraction of vanillin and its quantification by high-performance liquid chromatography in Vanilla planifolia.

    Science.gov (United States)

    Sharma, Anuj; Verma, Subash Chandra; Saxena, Nisha; Chadda, Neetu; Singh, Narendra Pratap; Sinha, Arun Kumar

    2006-03-01

    Microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and conventional extraction of vanillin and its quantification by HPLC in pods of Vanilla planifolia is described. A range of nonpolar to polar solvents were used for the extraction of vanillin employing MAE, UAE and conventional methods. Various extraction parameters such as nature of the solvent, solvent volume, time of irradiation, microwave and ultrasound energy inputs were optimized. HPLC was performed on RP ODS column (4.6 mm ID x 250 mm, 5 microm, Waters), a photodiode array detector (Waters 2996) using gradient solvent system of ACN and ortho-phosphoric acid in water (0.001:99.999 v/v) at 25 degrees C. Regression equation revealed a linear relationship (r2 > 0.9998) between the mass of vanillin injected and the peak areas. The detection limit (S/N = 3) and limit of quantification (S/N = 10) were 0.65 and 1.2 microg/g, respectively. Recovery was achieved in the range 98.5-99.6% for vanillin. Maximum yield of vanilla extract (29.81, 29.068 and 14.31% by conventional extraction, MAE and UAE, respectively) was found in a mixture of ethanol/water (40:60 v/v). Dehydrated ethanolic extract showed the highest amount of vanillin (1.8, 1.25 and 0.99% by MAE, conventional extraction and UAE, respectively).

  19. Influence of Accelerated Solvent Extraction and Ultrasound-Assisted Extraction on the Anthocyanin Profile of Different Vaccinium Species in the Context of Statistical Models for Authentication.

    Science.gov (United States)

    Heffels, Peter; Weber, Fabian; Schieber, Andreas

    2015-09-01

    Anthocyanins are frequently discussed as marker compounds for fruit product authenticity. Proper analysis including sample preparation for the determination of anthocyanin concentrations is crucial for the comparability of authenticity data. The present study determined the influence of accelerated solvent extraction (ASE) and ultrasound-assisted extraction (UAE), using two different solvent compositions on the anthocyanin profile of bilberries (Vaccinium myrtillus L.), lowbush blueberries (Vaccinium angustifolium Ait.), and American cranberries (Vaccinium macrocarpon Ait.). Besides differences in total anthocyanin concentrations in the extracts, significant deviations (p ≤ 0.05) in the individual anthocyanin concentration were observed, resulting in differing anthocyanin proportions. Linear discriminant analysis comparing the differences caused by the extraction method to the natural differences within a set of 26 bilberry and lowbush blueberry samples of different origins was conducted. It revealed that profile variations induced by the extraction methods are in a similar scale to profile variations as a result of geographic and climatic differences. PMID:26330254

  20. Fractional determination of some metallic elements including rate earth elements, thorium and uranium in agricultural soil by a sequential extraction procedure

    International Nuclear Information System (INIS)

    In order to investigate the behavior and distribution of metallic elements including rare earth elements(REEs), thorium(Th) and uranium(U) in the agricultural field, these elements in agricultural soils were partitioned into 6 fractions by a sequential extraction procedure: water soluble(F1), exchangeable(F2), bound to inorganic matter(F3), bound to organic matter(F4), bound to free oxides(F5) and residual(F6) fractions, and determined for each fraction as well as for total amount. Soil samples were collected from the agricultural field (paddy and upland field) and non-agricultural field in Sakata City (from 2005 to 2010) and Murayama City (from 2008 to 2010) in Yamagata Prefecture, and Sekikawa Village, Iwafune District (from 2007 to 2010) in Niigata Prefecture. Consequently, the following matters have been mainly clarified. (1) The distribution proportion of metallic elements among six fractions of the soils are varied depending on elements and soil utilization(i.e., paddy, upland or no plow). Among REEs, the tendency that the proportion of F5 of heavy-REE(HREE) is generally larger than that of light-REE(LREE) or in middle-REE(MREE) can be found. (2) The differences of REEs concentrations(or REE pattern) of soils are observed among sampling points. It can be related to the nature of soil including the content of Fe-Mn oxides or organic carbon (i.e., the affinity for free oxides or organic matter). (3) The distribution proportion as well as total concentrations of metallic elements in soils are not greatly varied regardless of sampling period(i.e., spring or autumn). (author)