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Extraction Methods (extraction + methods)
Kinds of Extraction Methods Selected AbstractsVariation in Emergency Department Wait Times for Children by Race/Ethnicity and Payment SourceHEALTH SERVICES RESEARCH, Issue 6 2009Christine Y. Park Objective. To quantify the variation in emergency department (ED) wait times by patient race/ethnicity and payment source, and to divide the overall association into between- and within-hospital components. Data Source. 2005 and 2006 National Hospital Ambulatory Medical Care Surveys. Study Design. Linear regression was used to analyze the independent associations between race/ethnicity, payment source, and ED wait times in a pooled cross-sectional design. A hybrid fixed effects specification was used to measure the between- and within-hospital components. Data Extraction Methods. Data were limited to children under 16 years presenting at EDs. Principal Results. Unadjusted and adjusted ED wait times were significantly longer for non-Hispanic black and Hispanic children than for non-Hispanic white children. Children in EDs with higher shares of non-Hispanic black and Hispanic children waited longer. Moreover, Hispanic children waited 10.4 percent longer than non-Hispanic white children when treated at the same hospital. ED wait times for children did not vary significantly by payment source. Conclusions. There are sizable racial/ethnic differences in children's ED wait times that can be attributed to both the racial/ethnic mix of children in EDs and to differential treatment by race/ethnicity inside the ED. [source] Assessing Treatment Effects of Inhaled Corticosteroids on Medical Expenses and Exacerbations among COPD Patients: Longitudinal Analysis of Managed Care ClaimsHEALTH SERVICES RESEARCH, Issue 6 2008Manabu Akazawa Objective. To assess costs, effectiveness, and cost-effectiveness of inhaled corticosteroids (ICS) augmenting bronchodilator treatment for chronic obstructive pulmonary disease (COPD). Data Sources. Claims between 1997 and 2005 from a large managed care database. Study Design. Individual-level, fixed-effects regression models estimated the effects of initiating ICS on medical expenses and likelihood of severe exacerbation. Bootstrapping provided estimates of the incremental cost per severe exacerbation avoided. Data Extraction Methods. COPD patients aged 40 or older with ,15 months of continuous eligibility were identified. Monthly observations for 1 year before and up to 2 years following initiation of bronchodilators were constructed. Principal Findings. ICS treatment reduced monthly risk of severe exacerbation by 25 percent. Total costs with ICS increased for 16 months, but declined thereafter. ICS use was cost saving 46 percent of the time, with an incremental cost-effectiveness ratio of $2,973 per exacerbation avoided; for patients ,50 years old, ICS was cost saving 57 percent of time. Conclusions. ICS treatment reduces exacerbations, with an increase in total costs initially for the full sample. Compared with younger patients with COPD, patients aged 50 or older have reduced costs and improved outcomes. The estimated cost per severe exacerbation avoided, however, may be high for either group because of uncertainty as reflected by the large standard errors of the parameter estimates. [source] An Empirical Taxonomy of Hospital Governing Board RolesHEALTH SERVICES RESEARCH, Issue 4 2008Shoou-Yih D. Lee Objective. To develop a taxonomy of governing board roles in U.S. hospitals. Data Sources. 2005 AHA Hospital Governance Survey, 2004 AHA Annual Survey of Hospitals, and Area Resource File. Study Design. A governing board taxonomy was developed using cluster analysis. Results were validated and reviewed by industry experts. Differences in hospital and environmental characteristics across clusters were examined. Data Extraction Methods. One-thousand three-hundred thirty-four hospitals with complete information on the study variables were included in the analysis. Principal Findings. Five distinct clusters of hospital governing boards were identified. Statistical tests showed that the five clusters had high internal reliability and high internal validity. Statistically significant differences in hospital and environmental conditions were found among clusters. Conclusions. The developed taxonomy provides policy makers, health care executives, and researchers a useful way to describe and understand hospital governing board roles. The taxonomy may also facilitate valid and systematic assessment of governance performance. Further, the taxonomy could be used as a framework for governing boards themselves to identify areas for improvement and direction for change. [source] Dementia and Medicare at Life's EndHEALTH SERVICES RESEARCH, Issue 2 2008Vicki L. Lamb Objective. To determine the effect of a diagnosis of Alzheimer's disease or related dementias (ADRD), and the timing of first ADRD diagnosis, on Medicare expenditures at end of life. Data Sources. Monthly Medicare payment data for the 5 years before death linked to the National Long-Term Care Survey (NLTCS) for decedents between 1996 and 2000 (N=4,899). Data Extraction Methods. Medicare payment data for the 5 years before death were used to compare 5-year and 6-month intervals of expenditures (total and six subcategories of services) for persons with and without a diagnosis of ADRD during the last 5 years of life, controlling for age, gender, race, education, comorbidities, and nursing home status. Covariate matching was used. Principal Findings. On average, ADRD diagnosis was not significantly associated with excess Medicare payments over the last 5 years of life. Regarding the timing of ADRD diagnosis, there were no significant 5-year total expenditure differences for persons diagnosed with dementia more than 1 year before death. Payment differences by 6-month intervals were highly sensitive to timing of ADRD diagnosis, with the highest differences occurring around the time of diagnosis. There were reduced, non-significant, or negative total payment differences after the initial diagnosis for those diagnosed at least 1 year before death. Only those diagnosed with ADRD in the last year of life had significantly higher Medicare payments during the last 12 months of life, primarily for acute care services. Conclusions. ADRD has a smaller impact on total Medicare expenditures than previously reported in controlled studies. The significant differences occur primarily around the time of diagnosis. Although rates of dementia are increasing per se, our results suggest that long-term (1+ year) ADRD diagnoses do not contribute to greater total Medicare costs at the end of life. [source] Factors Associated with Physician Interventions to Address Adolescent SmokingHEALTH SERVICES RESEARCH, Issue 3 2004Tammy H. Sims Objective. To determine the percent of adolescent Medicaid patients with medical record documentation about tobacco use status and cessation assistance; and factors associated with providers documenting and intervening with adolescent smokers. Data Source. Secondary analysis of data collected in 1999 from medical records of Wisconsin Medicaid health maintenance organization (HMO) recipients 11 to 21 years old. Study Design. Random reviews and data collection were related to visits from January 1997 to January 1999. Data collected included patient demographics, provider type, number of visits, and whether smoking status and cessation interventions were documented. Data Extraction Methods. Medical charts were reviewed and a database was created using a data abstraction tool developed and approved by a committee to address tobacco use in Medicaid managed care participants. Principal Findings. Among adolescents seen by a physician from 1997 to 1999, tobacco use status was documented in 55 percent of patient charts. Most often tobacco use status was documented on history and physical or prenatal forms. Of identified adolescent smokers, 50 percent were advised to quit, 42 percent assisted, and 16 percent followed for smoking cessation. Pregnant patients were more likely to have tobacco use documented than nonpregnant patients (OR=10.8, 95 percent CI=4.9 to 24). The odds of documentation increased 21 percent for every one-year increase in patient age. Conclusions. Providers miss opportunities to intervene with adolescents who may be using tobacco. Medical record prompts, similar to the tobacco use question on prenatal forms and the tobacco use vital sign stamp, are essential for reminding providers to consistently document and address tobacco use among adolescents. [source] The Costs of Decedents in the Medicare Program: Implications for Payments to Medicare+Choice PlansHEALTH SERVICES RESEARCH, Issue 1 2004Melinda Beeuwkes Buntin Objective. To discuss and quantify the incentives that Medicare managed care plans have to avoid (through selective enrollment or disenrollment) people who are at risk for very high costs, focusing on Medicare beneficiaries in the last year of life,a group that accounts for more than one-quarter of Medicare's annual expenditures. Data Source. Medicare administrative claims for 1994 and 1995. Study Design. We calculated the payment a plan would have received under three risk-adjustment systems for each beneficiary in our 1995 sample based on his or her age, gender, county of residence, original reason for Medicare entitlement, and principal inpatient diagnoses received during any hospital stays in 1994. We compared these amounts to the actual costs incurred by those beneficiaries. We then looked for clinical categories that were predictive of costs, including costs in a beneficiary's last year of life, not accounted for by the risk adjusters. Data Extraction Methods. The analyses were conducted using claims for a 5 percent random sample of Medicare beneficiaries who died in 1995 and a matched group of survivors. Principal Findings. Medicare is currently implementing the Principal Inpatient Diagnostic Cost Groups (PIP-DCG) risk adjustment payment system to address the problem of risk selection in the Medicare+Choice program. We quantify the strong financial disincentives to enroll terminally ill beneficiaries that plans still have under this risk adjustment system. We also show that up to one-third of the selection observed between Medicare HMOs and the traditional fee-for-service system could be due to differential enrollment of decedents. A risk adjustment system that incorporated more of the available diagnostic information would attenuate this disincentive; however, plans could still use clinical information (not included in the risk adjustment scheme) to identify beneficiaries whose expected costs exceed expected payments. Conclusions. More disaggregated prospective risk adjustment methods and alternative payment systems that compensate plans for delivering care to certain classes of patients should be considered to ensure access to high-quality managed care for all beneficiaries. [source] Improving Care for Minorities: Can Quality Improvement Interventions Improve Care and Outcomes For Depressed Minorities?HEALTH SERVICES RESEARCH, Issue 2 2003Controlled Trial, Results of a Randomized Objective. Ethnic minority patients often receive poorer quality care and have worse outcomes than white patients, yet practice-based approaches to reduce such disparities have not been identified. We determined whether practice-initiated quality improvement (QI) interventions for depressed primary care patients improve care across ethnic groups and reduce outcome disparities. Study Setting. The sample consists of 46 primary care practices in 6 U.S. managed care organizations; 181 clinicians; 398 Latinos, 93 African Americans, and 778 white patients with probable depressive disorder. Study Design. Matched practices were randomized to usual care or one of two QI programs that trained local experts to educate clinicians; nurses to educate, assess, and follow-up with patients; and psychotherapists to conduct Cognitive Behavioral Therapy. Patients and physicians selected treatments. Interventions featured modest accommodations for minority patients (e.g., translations, cultural training for clinicians). Data Extraction Methods. Multilevel logistic regression analyses assessed intervention effects within and among ethnic groups. Principal Findings. At baseline, all ethnic groups (Latino, African American, white) had low to moderate rates of appropriate care and the interventions significantly improved appropriate care at six months (by 8,20 percentage points) within each ethnic group, with no significant difference in response by ethnic group. The interventions significantly decreased the likelihood that Latinos and African Americans would report probable depression at months 6 and 12; the white intervention sample did not differ from controls in reported probable depression at either follow-up. While the intervention significantly improved the rate of employment for whites and not for minorities, precision was low for comparing intervention response on this outcome. It is important to note that minorities remained less likely to have appropriate care and more likely to be depressed than white patients. Conclusions. Implementation of quality improvement interventions that have modest accommodations for minority patients can improve quality of care for whites and underserved minorities alike, while minorities may be especially likely to benefit clinically. Further research needs to clarify whether employment benefits are limited to whites and if so, whether this represents a difference in opportunities. Quality improvement programs appear to improve quality of care without increasing disparities, and may offer an approach to reduce health disparities. [source] Extraction and analysis of colourful eggshell pigments using HPLC and HPLC/electrospray ionization tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 6 2009A. Gorchein Abstract The literature on the pigments of avian eggshells is critically reviewed. Methods using methanolic sulfuric acid or hydrochloric acid to extract eggshell pigments are unsuitable to detect the occurrence of zinc protoporphyrin or zinc biliverdin because they demetallate these compounds. Extraction methods are described here using EDTA and acetonitrile,acetic acid or acetonitrile,dimethyl sulfoxide, which do not demetallate zinc protoporphyrin. Such extracts were prepared from eggshell of the common nighthawk, Chordeiles minor, and from another six bird species. Protoporphyrin and biliverdin were identified and fully characterized by HPLC/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS) in all samples, but none contained zinc protoporphyrin. The zinc complex of biliverdin, claimed to be an additional pigment responsible for eggshell background colours, was labile to EDTA and acid pH and if occurring naturally could not be extracted intact by the published or the modified protocols. An explanation is advanced for the exceptional report that all porphyrins from uroporphyrin to protoporphyrin were found in eggshells of the fowl Gallus domesticus. Copyright © 2009 John Wiley & Sons, Ltd. [source] Sugarcane proteomics: Establishment of a protein extraction method for 2-DE in stalk tissues and initiation of sugarcane proteome reference mapELECTROPHORESIS, Issue 12 2010Ramesh Sundar Amalraj Abstract Sugarcane is an important commercial crop cultivated for its stalks and sugar is a prized commodity essential in human nutrition. Proteomics of sugarcane is in its infancy, especially when dealing with the stalk tissues, where there is no study to date. A systematic proteome analysis of stalk tissue yet remains to be investigated in sugarcane, wherein the stalk tissue is well known for its rigidity, fibrous nature, and the presence of oxidative enzymes, phenolic compounds and extreme levels of carbohydrates, thus making the protein extraction complicated. Here, we evaluated five different protein extraction methods in sugarcane stalk tissues. These methods are as follows: direct extraction using lysis buffer (LB), TCA/acetone precipitation followed by solubilization in LB, LB containing thiourea (LBT), and LBT containing tris, and phenol extraction. Both quantitative and qualitative protein analyses were performed for each method. 2-DE analysis of extracted total proteins revealed distinct differences in protein patterns among the methods, which might be due to their physicochemical limitations. Based on the 2-D gel protein profiles, TCA/acetone precipitation-LBT and phenol extraction methods showed good results. The phenol method showed a shift in pI values of proteins on 2-D gel, which was mostly overcome by the use of 2-D cleanup kit after protein extraction. Among all the methods tested, 2-D cleanup-phenol method was found to be the most suitable for producing high number of good-quality spots and reproducibility. In total, 30 and 12 protein spots commonly present in LB, LBT and phenol methods, and LBT method were selected and subjected to eLD -IT-TOF-MS/MS and nESI-LC-MS/MS analyses, respectively, and a reference map has been established for sugarcane stalk tissue proteome. A total of 36 nonredundant proteins were identified. This is a very first basic study on sugarcane stalk proteome analysis and will promote the unexplored areas of sugarcane proteome research. [source] Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2006,2008)ELECTROPHORESIS, Issue 1 2009Michael C. Breadmore Abstract Poor sensitivity is still considered to be one of the major limitations of electrophoresis, which is surprising given the power, flexibility and versatility of many of the approaches to on-line concentration that have developed over the last 20 years. This is still a very active area of interest and this review will cover developments in the field over the last two years since the last review (Electrophoresis 2007, 28, 254,281) through to June 2008. It includes developments in the fields of stacking, covering all methods from field-amplified sample stacking and large volume sample stacking, through to ITP, dynamic pH junction and sweeping. Attention is also given to on-line or in-line extraction methods that have been used for electrophoresis. [source] Proteomic analysis of rat brain tissue: Comparison of protocols for two-dimensional gel electrophoresis analysis based on different solubilizing agentsELECTROPHORESIS, Issue 24 2002Lucia Carboni Abstract The present study reports a comparison of recently described solubilizing methods, to set up a simple protocol for obtaining two-dimensional (2-D) gel electrophoresis maps of brain tissue. Different protocols were used for preparing rat brain homogenates and the resulting maps were compared by image analysis. Three different detergents, two delipidation methods, and introduction of a fractionation step based on different protein solubility in surfactants, were evaluated. When using efficient zwitterionic detergents (3-[(3-cholamidopropyl)dimethylamino]-1-propanesulfonate, CHAPS; amidosulfobetaine 14, ASB-14), the patterns obtained by direct loading of total extracts were qualitatively overlapping with patterns obtained from fractionated samples. In contrast, a weaker nonionic agent (Nonidet P-40, NP-40) produced a different protein pattern in the collected fractions. Delipidation did not improve the results for all the different extraction methods. Immunoblots performed with antibodies recognizing cytosolic and membrane-spanning proteins, which were detected as nondegraded spots, showed that membrane proteins with intermediate molecular mass could be recovered. We suggest, as a simple and efficient method for preparing rat brain maps, the homogenization in a solution containing an efficient zwitterionic surfactant, which allows to solubilize cytosolic and membrane proteins in a single step. Alternatively, a fractionation can be carried out on samples homogenized by a weak solubilizing agent, a more labor-intensive effort resulting in a larger number of proteins on two maps. [source] Quantification of bacterial subgroups in soil: comparison of DNA extracted directly from soil or from cells previously released by density gradient centrifugationENVIRONMENTAL MICROBIOLOGY, Issue 7 2001Sophie Courtois All molecular analyses of soil bacterial diversity are based on the extraction of a representative fraction of cellular DNA. Methods of DNA extraction for this purpose are divided into two categories: those in which cells are lysed within the soil (direct extraction) and those in which cells are first removed from soil (cell extraction) and then lysed. The purpose of this study was to compare a method of direct extraction with a method in which cells were first separated from the soil matrix by Nycodenz gradient centrifugation in order to evaluate the effect of these different approaches on the analysis of the spectrum of diversity in a microbial community. We used a method based on polymerase chain reaction (PCR) amplification of a 16S rRNA gene fragment, followed by hybridization of the amplified fragments to a set of specific probes to assess the phylogenetic diversity of our samples. Control parameters, such as the relationship between amount of DNA template and amount of PCR product and the influence of competing DNA on PCR amplification, were first examined. Comparison between extraction methods showed that less DNA was extracted when cells were first separated from the soil matrix (0.4 µg g,1 dry weight soil versus 38,93 µg g,1 obtained by in situ lysis methods). However, with the exception of the ,-subclass of Proteobacteria, there was no significant difference in the spectrum of diversity resulting from the two extraction strategies. [source] Bauxite manufacturing residues from Gardanne (France) and Portovesme (Italy) exert different patterns of pollution and toxicity to sea urchin embryosENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2002Giovanni Pagano Abstract This study was designed to investigate the composition and toxicity of solid residues from bauxite manufacturing plants. Soil and dust samples were collected in the proximity of two bauxite plants (Gardanne, France, and Portovesme, Italy). Samples were analyzed for their content of some selected inorganic contaminants by means of inductively coupled plasma optical emission spectroscopy (ICP-OES) either following acid digestion procedures or by seawater release of soluble components. Toxicity was tested by sea urchin bioassays to evaluate a set of toxicity endpoints including acute embryotoxicity, developmental defects, changes in sperm fertilization success, transmissible damage from sperm to the offspring, and cytogenetic abnormalities. Inorganic analysis showed two distinct sets of inorganic contaminants in Gardanne versus Portovesme, including Al, Cr, Cu, Fe, Mn, Pb, Ti, and Zn; sample composition (seawater-soluble cotaminants) and toxicity showed a noteworthy association. The most severe toxicity to embryogenesis and to sperm fertilization success was exerted by some Portovesme samples (0.03,0.5% w/v), with a significant association between toxicity and dose-related seawater release of Zn, Pb, and Mn. Seawater extraction of a toxic dust sample (G20) from the Gardanne factory showed increasing seawater release of Al, Fe, and Mn; the G20 sample, at the level of 0.5%, affected both developing sea urchin embryos and sperm (offspring quality). Soil samples around the Gardanne factory showed the highest frequency of toxic soil sites eastward from the factory. The present data point to solid deposition from bauxite plants as a potential subject of environmental health concern. The results suggest that extraction methods for evaluating the toxicity of complex mixtures should be based on the environmental availability of mixture components. The differences in sample toxicity among the tested sites, however, suggest possible site-to-site variability in geochemical and/or technological parameters. [source] Cytotoxicity of settling particulate matter and sediments of the Neckar River (Germany) during a winter floodENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2000Henner Hollert Abstract To investigate the cytotoxic and genotoxic potentials of settling particulate matter (SPM) carried by the Neckar River, a well-studied model for a lock-regulated river in central Europe, during a flood, acute cytotoxicity was investigated using the fibroblast-like fish cell line RTG-2 with the neutral red retention, the succinic acid dehydrogenase (MTT), and the lactatedehydro-genase (LDH) release assays as well as microscopic inspection as endpoints. Genotoxicity of water, pore water, sediments, and SPM were assessed using the Ames test. Different extraction methods (Soxhlet extraction with solvents of variable polarity as well as a fluid/fluid extraction according to pH) in addition to a supplementation of biotests with S9 fractions from the liver of ,-naphthoflavone/phenobarbital-induced rats allowed a further characterization of the biological damage. Both sediments and SPM extracts caused cytotoxic effects in RTG-2 cells. Cytotoxicity was found to increase significantly with polarity of extracting solvents (NR50 = effective concentration for 50% cell death in the neutral red test: 80 [65], 100 [70], 180 [220], and 225 [270] mg/ml for ethanol, acetone, dichloromethane, and n -hexane extracts, respectively, if measured with [without] S9 supplementation). Following extraction according to pH, cytotoxicity could be attributed mainly to neutral substances (NR50: 80 and 218 mg dry SPM/ml test medium for the neutral and the acid fractions, respectively), whereas the slightly acid and basic fractions already showed little or no cytotoxicity. Samples taken during the period of flood rise showed the highest cytotoxic activities. Cytotoxicity was significantly enhanced by the addition of S9 preparations. In contrast, no genotoxic activity was found in native surface waters, pore waters, and SPM. [source] Direct examination of soil for sporangia of Synchytrium endobioticum using chloroform, calcium chloride and zinc sulphate as extraction reagentsEPPO BULLETIN, Issue 1 2005G. C. M. Van Leeuwen Fields infested with Synchytrium endobioticum can be descheduled when the soil is found free from sporangia of S. endobioticum. For direct examination, EPPO Standard PM 3/59 describes a soil extraction technique based on the use of a sieve shaker with six sieves. We compared recovery of sporangia between this (modified) method and an extraction method employed by the Dutch Plant Protection Service (PPS method). Recovery was determined using an inoculum dilution series: 125, 25, 5, 1, 0.2 or 0.04 sporangia per g soil. Extraction reagents used were chloroform and calcium chloride in the method described by EPPO, calcium chloride and zinc sulphate in the PPS method. At 125 sporangia per g soil, the mean density determined for the modified EPPO method was 228 sporangia per g soil when chloroform was used. Using calcium chloride, recovery percentage was higher for the modified EPPO method than for the PPS method (286, 136%, n.s. P < 0.05). The advantage of the modified EPPO method was the larger soil volume to be processed; its disadvantages were use of complex equipment and noxious reagents (chloroform). Both extraction methods showed high variation in recovery between samples, making accurate estimation of sporangial densities in soil awkward. [source] Comparison of the effectiveness of five extraction methods for Clavibacter michiganensis subsp. sepedonicus and Ralstonia solanacearum from potato tubersEPPO BULLETIN, Issue 2 2001J. Martin In the EU Control Directives, the recommended extraction procedure for testing potatoes for Clavibacter michiganensis subsp. sepedonicus and Ralstonia solanacearum comprises incubation followed by differential centrifugation. This method can be qualified as complex because of the number of different steps required. This study evaluates five different extraction methods for each bacterium from both a technical point of view and for the quality of the results. Results showed that in the case of C. m. sepedonicus the clarification step should be avoided. The incubation/shaking method with three subsamples gives at least as satisfactory results as the official EU procedure. It also has other advantages, facilitating immunofluorescence readings due to the reduced quantity of plant debris, and improving the speed and the reliability of the analysis. [source] Oxidative stability of Echium plantagineum seed oil bodiesEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010David A. Gray Abstract Echium plantagineum seed contains a highly polyunsaturated oil (approximately 14% linoleic acid, 10% ,-linolenic acid, 33% ,-linolenic acid and 14% stearidonic acid); almost half of the fatty acids are omega-3 fatty acids, so there is an interest in the possible health benefits of this oil, which, once extracted, is prone to oxidation. For the first time in reported literature, oil bodies (OBs), the organelles that store the oil in mature seed, were recovered from E. plantagineum seeds. The oxidative stability of these organelles ex vivo, dispersed in an aqueous continuous phase, was tested against processed E. plantagineum oil emulsions stabilised with either SDS or Tween 20. For both primary and secondary oxidation products the OBs were the most stable form of dispersed oil, and the dispersed systems were all more stable than bulk E. plantagineum oil after incubating at 40°C for 7 days. The possible reasons for the enhanced chemical stability of E. plantagineum OBs are explored in this paper. Practical applications: OBs, the natural store of oil in oilseeds, can be recovered from seeds intact and are relatively stable to oxidation ex vivo. Echium seed OBs, enriched in physiologically active omega-3 fatty acids, therefore offer an attractive alternative to traditional oil extraction methods and overcome the need to encapsulate the omega-3 rich oil. [source] Effect of various extraction conditions on the phenolic contents of pomegranate seed oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2008Hajar Abbasi Abstract Pomegranate seeds are byproducts of the pomegranate juice industry. Because of the presence of large amounts of certain pharmaceutical and nutraceutical components in the seeds, a proper extraction method to obtain these components is highly demanded in the food industry. In this study, the effect of different extraction methods on the total phenolic contents of the oil extracted from pomegranate seeds of the Malas variety from Shahreza, Iran, was investigated. Four different extraction methods including normal stirring, Soxhlet, microwave irradiation and ultrasonic irradiation using two types of organic solvents as well as a supercritical fluid extraction (SFE) method using CO2 as solvent were applied. The different organic solvents of this study did not indicate any significant differences in the total phenolic contents of the extracted oils, but the extracted oils from the various conditions of SFE indicated wide changes in the amount of phenolic compounds (7.8,72.1,mg/g). The total phenolic content of the extracted oil from one of the SFE runs was several times greater than those in the extracted oils using organic solvents. [source] Soil metaproteomics: a review of an emerging environmental science.EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2009Significance, methodology, perspectives Summary Soil is a dynamic system in which microorganisms perform important tasks in organic matter transformations and nutrient cycles. Recently, some studies have started to focus on soil metaproteomics as a tool for understanding the function and the role of members of the microbial community. The aim of our work was to provide a review of soil proteomics by looking at the methodologies used in order to illustrate the challenges and gaps in this field, and to provide a broad perspective about the use and meaning of soil metaproteomics. The development of soil metaproteomics is influenced strongly by the extraction methods. Several methods are available but only a few provide an identification of soil proteins, while others extract proteins and are able to separate them by electrophoresis but do not provide an identification. The extraction of humic compounds together with proteins interferes with the latter's separation and identification, although some methods can avoid these chemical interferences. Nevertheless, the major problems regarding protein identification reside in the fact that soil is a poor source of proteins and that there is not enough sequence-database information for the identification of proteins by mass spectrometric analysis. Once these pitfalls have been solved, the identification of soil proteins may provide information about the biogeochemical potential of soils and pollutant degradation and act as an indicator of soil quality, identifying which proteins and microorganisms are affected by a degradation process. The development of soil metaproteomics opens the way to proteomic studies in other complex substrates, such as organic wastes. These studies can be a source of knowledge about the possibility of driven soil restoration in polluted and degraded areas with low organic matter content and even for the identification of enzymes and proteins with a potential biotechnological value. [source] The effect of aging biosolids on the availability of cadmium and zinc in soilEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2001S. Stacey Summary A major concern with the safe re-use of biosolids on land is the potential for release of metals from organic matter in the biosolids, due to decomposition proceeding as biosolids age. To quantify the effects of biosolid aging on Cd and Zn bioavailability, two sewage sludges (Lagoon sludge and Filtered sludge) and a garden compost were incubated at 25°C and 35°C for 100 days. Changes in availability of Cd and Zn were determined using isotope dilution principles, with the materials being labelled with carrier-free 109Cd and 65Zn. We determined isotopically exchangeable metal pools (E values) and plant available metal pools (L values) by measuring specific activities of Cd and Zn in soil extracts and in wheat plants, respectively. Changes in carbon content over time were determined using 13C-NMR spectroscopy and chemical extraction methods, and related to changes in availability of metal pools as determined by isotopic procedures. Hot-water-extractable carbon content, assumed to represent easily decomposable organic matter, decreased during the 100 days by 80,190 mg kg,1. The Compost and Lagoon sludge showed no change in L values for Cd or Zn with time, but in the Filtered sludge the L values for Cd and Zn increased significantly, by 43% and 56%, respectively. The isotopically exchangeable pools of Cd and Zn did not change with incubation treatment of the biosolids. These data indicate that the potential for metal release from biosolids as organic matter decomposes depends to a large extent on the biosolid composition. [source] Immunological quantification of the nematode parasitic bacterium Pasteuria penetrans in soilFEMS MICROBIOLOGY ECOLOGY, Issue 3 2001S Fould Abstract Currently, the abundance of Pasteuria penetrans in soils, an unculturable bacterial parasite of root-knot nematodes (Meloidogyne spp.), is estimated by the percentage of nematode juveniles infected with bacteria and the number of spores attached to their cuticle. Indirect immunofluorescence led to detection of free spores directly in soil suspensions using UV light and polyclonal antibodies raised against two P. penetrans populations (ORS-21414-Sen and PP1). Three extraction methods were compared in order to improve spore recovery. A gentle shaking/sieving method recovered more than 90% of the spores inoculated in soils and was more efficient and simple than aqueous two-phase partitioning and polyethylene glycol extractions. All the spores inoculated in sandy or sandy,clay soils were detected with immunofluorescence microscopy. The quantification of the spores was improved using an ELISA technique that showed a good correlation between optical density and spore concentration in inoculated soils. Specific antibodies provide a suitable method to quantify P. penetrans and may be used to follow the evolution of the real pool of bacteria either in native suppressive soils or in inoculated ones. [source] Aroma-impact compounds in Lysimachia foenum-graecum extractsFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2009Na Shu Abstract Two different extraction methods were used to obtain representative extracts from stems and leaves of Lysimachia foenum-graecum, a Chinese plant with a smoky, spicy, green, woody and caramel aroma. An extract was obtained by steam distillation followed by pentane back-extraction. Plants were also extracted with dichloromethane, and the non-volatile compounds were separated from volatiles by high-vacuum distillation (SAFE). Compared to the steam distillate extract, the SAFE-distilled extract was judged to be more similar to the aroma of the starting materials. The aroma-impact compounds of the SAFE extract were then determined using multidimensional GC. From the detection frequencies and the intensities of the peaks, 47 peaks with odour-activity were determined, using an adaptation of the GC,SNIFF method, to have an impact on the overall aroma of the extract. Fifty-four compounds responsible for the peaks presenting odour-activity were identified from mass spectral data, retention indices, olfactory character and co-injection of authentic standards. Copyright © 2008 John Wiley & Sons, Ltd. [source] New RF extrinsic resistances extraction procedure for deep-submicron MOS transistorsINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 2 2010J. C. Tinoco Abstract The modeling of MOS transistors used for RF applications needs the definition of a lumped equivalent circuit where the intrinsic device and series extrinsic resistances are properly evaluated. The model accuracy depends on the extraction precision of each intrinsic lumped element. In order to determine the intrinsic device behavior, it is necessary to first remove the series extrinsic resistances. For this reason their extraction becomes critical for the modeling of MOS transistors in RF circuit design. Several extraction methods have been proposed; nevertheless, the measurement noise strongly affects the obtained results. The method proposed by Bracale and co-workers is the most robust extraction procedure against measurement noise, but fails to predict correctly the series extrinsic resistances for deep-submicron devices. For those reasons, we deeply analyze the method proposed by Bracale in order to understand and then overcome its limitations. Based on those analyses, a robust extraction method for deep-submicron devices is proposed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Numerically distributed circuit parameters model on microstrip transmission line circuits and its application on CADINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 4 2003Xiaolong Zhong Abstract A new numerical model of microstrip transmission line circuits in terms of distributed circuit parameters is here illustrated. Based on full-wave electromagnetic results, the extraction methods of these distributed circuit parameters on different types of microstrip transmission line circuits are introduced. As a preparatory experiment, an improved CAD method using this model is tested on microstrip low-pass filter. Copyright © 2003 John Wiley & Sons, Ltd. [source] Bacterial synthesis of biodegradable polyhydroxyalkanoatesJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007R.A.J. Verlinden Summary Various bacterial species accumulate intracellular polyhydroxyalkanoates (PHAs) granules as energy and carbon reserves inside their cells. PHAs are biodegradable, environmentally friendly and biocompatible thermoplastics. Varying in toughness and flexibility, depending on their formulation, they can be used in various ways similar to many nonbiodegradable petrochemical plastics currently in use. They can be used either in pure form or as additives to oil-derived plastics such as polyethylene. However, these bioplastics are currently far more expensive than petrochemically based plastics and are therefore used mostly in applications that conventional plastics cannot perform, such as medical applications. PHAs are immunologically inert and are only slowly degraded in human tissue, which means they can be used as devices inside the body. Recent research has focused on the use of alternative substrates, novel extraction methods, genetically enhanced species and mixed cultures with a view to make PHAs more commercially attractive. [source] Ochratoxin A removal in synthetic and natural grape juices by selected oenological Saccharomyces strainsJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2004H. Bejaoui Abstract Aims:, To assess, for the first time the efficiency in removing ochratoxin A (OTA) from laboratory medium [yeast peptone glucose (YPG)], synthetic grape juice medium (SGM) and natural grape juice by viable and dead (heat and acid-treated) oenological Saccharomyces strains (five S. cerevisiae and one S. bayanus) compared with a commercial yeast walls additive. Methods and Results:, Levels of OTA during its interaction with six oenological Saccharomyces strains (five S. cerevisiae and one S. bayanus) or with a commercial yeast walls additive in YPG medium, in SGM or in natural grape juices was assessed by HPLC after appropriate extraction methods. A significant decrease of OTA levels in YPG medium and SGM was observed for many of the growing strains reaching a maximum of 45%, but no degradation products were detected. With both heat and acid pretreated yeasts, OTA removal was enhanced, indicating that adsorption, not catabolism, is the mechanism to reduce OTA concentrations. Adsorption was also improved when the yeast concentration was increased and when the pH of the medium was lower. Approximately 90% of OTA was bound rapidly within 5 min and up to 72 h of incubation with heat-treated cells of either S. cerevisiae or S. bayanus. A comparative study between heat-treated cells (HC) and commercial yeast walls (YW) (used as oenological additive), introduced at two different concentrations (0·2 and 6·7 g l,1) in an OTA-contaminated grape juice, showed the highest efficiency by HC to adsorb rapidly within 5 min the total amount of the mycotoxin. Conclusions:, Oenological S. cerevisiae and S. bayanus were able to remove ochatoxin A from synthetic and natural grape juices. This removal was rapid and improved by dead yeasts having more efficiency than commercial yeast walls. Significance and Impact of the Study:, The efficiency of heat-treated yeasts to remove OTA gives a new hope for grape juice and must decontamination avoiding negative impacts on human health. [source] APPLICATION OF ULTRASONICATION OR HIGH-PRESSURE EXTRACTION OF FLAVONOIDS FROM LITCHI FRUIT PERICARPJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2009K. NAGENDRA PRASAD ABSTRACT Litchi (Litchi chinensis Sonn.) fruit pericarp (LFP) contains a high amount of flavonoids, which could be used as natural antioxidants. Some emerging novel technologies, such as ultrasonic extraction (UE) and high-pressure extraction (HPE), have exhibited great potential for flavonoid extraction. Experiments were conducted to comparatively investigate the effects of conventional extraction (CE), 40-KHz UE and 200- or 400-MPa HPE on the extraction efficiency of flavonoids from LFP. After 30 min of extraction, the extract yield, total phenolic content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide anion scavenging ability were examined. The crude extract yields by the UE, 400 HPE and CE were 24, 30 and 1.83%, respectively. However, there were no significant differences (P > 0.05) in the total phenolic content and antioxidant activity tested among these three different extractions at the same concentration. In addition, two flavonoids, namely epicatechin and epicatechin gallate, were identified and quantified as the major compounds, while catechin and procyanidin B2 were identified as the minor compounds. The total flavonoid content detected was 0.65, 0.75, 0.29 and 0.07 mg/g dry weight by HPE at 200 and 400 MPs, UE, and CE, respectively. Thus, the HPE technique showed a higher efficiency in extracting flavonoids from LFP, and the HPE could reduce the extraction time and increase the amount of the extracted phenolics. PRACTICAL APPLICATIONS Litchi (Litchi chinensis Sonn.) is a subtropical fruit that originated in Southeast Asia. As litchi fruit is gradually accepted by consumers for its delicious taste and attractive red skin, litchi production has steadily increased in recent decades, with increasing exports to Europe and North America from both the southern and northern hemisphere production areas. Litchi fruit pericarp (LFP) accounts for approximately 16% by weight of the whole fresh fruit and is comprised of a significant amount of flavonoids. Therefore, LFP tissues may be considered an important source of dietary flavonoids. This work showed that HPE technique has a high efficiency in extracting flavonoids from LFP tissues, which may help the litchi industry develop new extraction methods to better utilize the flavonoids from LFP tissues. [source] INFLUENCE OF SUPERCRITICAL CARBON DIOXIDE AND METHANOLIC EXTRACTS OF ROSEMARY ON OXIDATION AND SENSORY PROPERTIES OF WHEAT GERM OILJOURNAL OF FOOD QUALITY, Issue 6 2009OZLEM YESIL-CELIKTAS ABSTRACT Both supercritical CO2 and methanolic extracts from the leaves of rosemary (Rosmarinus officinalis) harvested from three different locations of Turkey at four different times of the year were added at a concentration of 100 mg/kg to wheat germ oil. Wheat germ oil samples were stored in an incubator for 10 days at 50C in order to promote oxidation and for the efficacy of the extracts for stabilization purposes to be examined. Degree of oxidation was determined by peroxide and p -anisidine values, which were performed every 2 days. Extracts from Mersin and Canakkale regions performed better results. Additionally, June and September harvests had lower peroxide values. According to the descriptive sensory analysis, both locations and extraction methods were found to effect flavor. Some flavor attributes, such as wheatlike/starchy, fishy and rubbery/metallic changed during storage regardless of locations and extraction methods. Supercritical CO2 extracts performed better results in terms of both oxidation and sensory properties. PRACTICAL APPLICATIONS From the perspective of the food industry, wheat germ oil stabilized with a natural antioxidant such as rosemary can be marketed as a functional product that can create a niche. Rosemary extracts containing higher amounts of rosmarinic acid and carnosic acid should be preferred in order to provide a better shelf life of an edible oil such as wheat germ oil. [source] Detection of Ralstonia solanacearum in Potato Tubers by Polymerase Chain ReactionJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2000K.-H. Pastrik Abstract A new polymerase chain reaction (PCR) assay was developed for the detection of Ralstonia solanacearum in potato tubers. The designed primers PS-1/PS-2 based on the sequence data of the 16S rRNA gene. Using the optimized PCR protocol, it was possible to detect R. solanacearum cells artificially added to concentrated potato extracts in the range of 1,10 colony-forming units (CFU) per PCR reaction mixture (10,100 CFU/ml potato homogenate). No amplification products were obtained, when bacteria belonging to other species or genera were submitted to PCR under the same conditions. A total of 10 different DNA extraction methods were adapted for the isolation of R. solanacearum DNA from potato homogenates and were compared for their suitability as pre-PCR procedures. Zusammenfassung Es wurde ein neuer PCR-Test entwickelt für die Detektion von Ralstonia solanacearum in Kartoffel-Knollen. Die entwickelten Primer PS-1/PS-2 basierten auf Sequenzdaten des 16S rRNA Gens. Mit dem optimierten PCR Protokoll war es möglich künstlich zugegebene R. solanacearum Zellen in konzentrierten Kartoffel-Homogenaten zu detektieren, bei einer Nachweis-Empfindlichkeit von 1,10 CFU pro PCR-Mix (10,100 CFU pro ml Kartoffel-Homogenat). Mit dem optimierten PCR Protokoll wurden keine Amplifikationsprodukte bei Bakterien anderer Arten oder Gattungen erhalten. Außerdem wurden 10 unterschiedliche DNA-Extraktionsmethoden getestet zur Isolierung von Ralstonia solanacearum DNA aus Kartoffel-Homogenat und ihre Eignung für die PCR verglichen. [source] Differentiation among various kinds of cheese by identification of casein using HPLC-chip/MS/MS,JOURNAL OF SEPARATION SCIENCE, JSS, Issue 16 2010Martin Franc Abstract In proteomics, proteins can be identified by enzymatic cleavage of the target protein using an enzyme of the known specificity (primarily trypsin), sequencing the obtained specific peptides by MS and comparing the amino acid sequence of the peptides with a protein database. The sophisticated approach described above was used in this study to determine and verify the original species of cheeses. Proteins were extracted from three different cheese samples which were produced from cow, sheep and goat milks. The isolated proteins were cleaved with trypsin and the peptides obtained were sequenced and identified by a HPLC-chip/MS/MS microfluidic system. Two different extraction methods and two various chromatographic sorbents packed in plastic chips were studied. ,-Lactoglobuline and four kinds of casein were found in the cheese samples. The species of ,-casein were identified unambiguously in all the three cheese samples and, thus, ,-casein can be used to determine the origin of milk of the cheese. The other proteins found in the samples show very similar primary structures and cannot be recommended for identification of the cheese milk origin. [source] | ||||||||||||||||||||||||||||||||||