bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reveal 8-Hour Test System for Detection of Escherichia coli O157:H7 in Raw Ground Beef, Raw Beef Cubes, and Iceberg Lettuce Rinse: Collaborative Study
Authors: Bird Charles B , Hoerner Rebecca J , Restaino Lawrence ,   Collaborators:, Anderson G , Birbari W , Bodra L , Brookman D , Bryant D , Campbell C , Degraft-Hanson J , Fetviet D , Forde R , Goins D , Hajkowski S , Haley E , Holland R , Jones J , Joseph J M , Kallewaard N , Keckeissen J , Kirkbride T , Kusch S , Noel D , Nutsch A , Okolo C , Parks K , Raines D , Remes A , Roach V , Robbins R , Rodrick G , Shelef L , Theissen H , Vasavada P C , Wang T 
Published: February 2020

Abstract
Five different food types were analyzed by the Reveal for E. coli O157:H7 8-Hour Test System (Reveal 8) and either the U.S. Food and Drug Administration's Bacteriological Analytical Manual (BAM) culture method or the U.S. Department of Agriculture Food Safety Inspection Service (FSIS) culture method for the presence of E. coli O157:H7. A total of 27 laboratories representing academia and private industry in the United States and Canada participated. Food types were inoculated with E. coli O157:H7 at 2 different levels: a high level where predominantly positive results were expected, and a low level where fractional recovery was anticipated. During this study, 1110 samples and controls were analyzed by both the Reveal 8 and by BAM or FSIS by each of the collaborators (2220 samples in total). For each set of samples, 740 were artificially inoculated with E. coli O157:H7, and 370 were uninoculated controls. The Reveal 8 detected 528 presumptive positives of which 487 were confirmed positive by the BAM culture method. In comparison, BAM and FSIS detected 489 of the 740 artificially contaminated samples as positive. In an additional in-house study performed only on chilled and frozen raw ground beef, 240 artificially inoculated samples were analyzed by both the Reveal 8 and by FSIS. The Reveal 8 detected and confirmed 104 samples as positive compared to 79 confirmed positive by FSIS.
Determination of Ephedrine-Type Alkaloids in Dietary Supplements by LC/MS Using a Stable-Isotope Labeled Internal Standard
Authors: Gay Martha L , White Kevin D , Obermeyer William R , Betz Joseph M , Musser Steven M 
Published: February 2020

Abstract
Arapid, isocratic method for the separation of 6 ephedrine-type alkaloids which may occur in dietary supplements was modified to permit quantitation and confirmation by liquid chromatography/mass spectrometry using atmospheric pressure chemical ionization. Several columns and sets of conditions were examined for suitability and the results compared. The use of ion-pairing reagents to enhance resolution is also reported. Mass spectrometric conditions were adjusted to provide sufficient fragmentation for qualitative identification of the analytes. Stable-isotope labeled ephedrine was used as an internal standard for quantitation.
Gas Chromatography with Pulsed Flame Photometric Detection Multiresidue Method for Organophosphate Pesticide and Metabolite Residues at the Parts-Per-Billion Level in Representative Commodities of Fruit and Vegetable Crop Groups
Authors: Podhorniak Lynda V , Negron Juan F , Griffith Francis D 
Published: February 2020

Abstract
A gas chromatographic method with a pulsed flame photometric detector (P–FPD) is presented for the analysis of 28 parent organophosphate (OP) pesticides and their OP metabolites. A total of 57 organophosphates were analyzed in 10 representative fruit and vegetable crop groups. The method is based on a judicious selection of known procedures from FDA sources such as the Pesticide Analytical Manual and Laboratory Information Bulletins, combined in a manner to recover the OPs and their metabolite(s) at the part-per-billion (ppb) level. The method uses an acetone extraction with either miniaturized Hydromatrix column partitioning or alternately a miniaturized methylene dichloride liquid–liquid partitioning, followed by solid-phase extraction (SPE) cleanup with graphitized carbon black (GCB) and PSA cartridges. Determination of residues is by programmed temperature capillary column gas chromatography fitted with a P–FPD set in the phosphorus mode. The method is designed so that a set of samples can be prepared in 1 working day for overnight instrumental analysis. The recovery data indicates that a daily column-cutting procedure used in combination with the SPE extract cleanup effectively reduces matrix enhancement at the ppb level for many organophosphates. The OPs most susceptible to elevated recoveries around or greater than 150%, based on peak area calculations, were trichlorfon, phosmet, and the metabolites of dimethoate, fenamiphos, fenthion, and phorate.
Determination of Pesticides in Composite Dietary Samples by Gas Chromatography/Mass Spectrometry in the Selected Ion Monitoring Mode by Using a Temperature-Programmable Large Volume Injector with Preseparation Column
Authors: Rosenblum Laura , Hieber Thomas , Morgan Jeffrey 
Published: February 2020

Abstract
Use of a temperature-programmable preseparation column in the gas chromatographic (GC) injection port permits determination of a wide range of semi-volatile pesticides including organochlorines, organophosphates, triazines, and anilines in fatty composite dietary samples while reducing sample preparation time and solvent consumption. Dietary samples are mixed with diatomaceous earth and are Soxhlet-extracted with an azeotropic solution of hexane and acetone. Sample preparation uses liquid–liquid partitioning over diatomaceous earth followed by normal phase chromatography over partially deactivated alumina. The final cleanup step occurs in a preseparation column in the GC injector, which is able to perform splitless transfer of the analytes to the analytical column and purge 99% of the high molecular weight residue. Detection is performed by GC/mass spectrometry (MS) in the selected ion monitoring mode. Method detection limits were at or below 2 ng/g for 24 of 35 pesticides studied, with recovery between 70 and 125% for 27 pesticides in samples fortified at 10 ng/g. Recovery was not dependent on fat content when measured in laboratory fortified samples containing 1, 5, and 10% fat by weight. Precision over multiple injections was acceptable, with a relative standard deviation of 2.6–15% for 25 analytes.
Determination of Azadirachtin in Agricultural Matrixes and Commercial Formulations by Enzyme-Linked Immunosorbent Assay
Authors: Hemalatha Kalidindi , Venugopal Namburi B K , Venugopal Namburi B K , Rao Beedu S 
Published: February 2020

Abstract
An enzyme-linked immunosorbent assay (ELISA) was developed for azadirachtin (aza), a biopesticide from the neem tree (Azadirachta indica A. Juss). The immunogen was synthesized by epoxidation using the furan ring in the aza molecule. Rabbits were immunized with either bovine serum albumin (BSA)-azadirachtin or ovalbumin (OA)-azadirachtin conjugate. Evaluation of the antisera by antibody capture assay showed that the antibody titer of antisera raised against OA-aza was 1:30 000. An indirect competitive ELISA was developed with BSA-azadirachtin as coating antigen and aza-specific antibodies raised against OA-aza immunogen. The immunoassay showed an inhibitory concentration (IC50) value of 75 ppb, with a range of detection from 0.5 to 1000 ppb for azadirachtin [based on regression analysis, y = 85.87 (−18.89x); r2 = −0.97]. Cross-reactivity of the antibodies with 2 aza- derivatives (22,23-dihydro-23β-methoxy azadirachtin and 3-tigloylazadirachtol) was 33 and 29%, respectively. The indirect competitive ELISA was validated and evaluated by quantitating aza in spiked agricultural commodities and from neem formulations. Azadirachtin was spiked into 5 different agricultural commodities: tomato, brinjal, coffee, tea, and cotton seed at 500 and 1000 ppb and recovered at 62–100%. In samples drawn from 6 lots, the aza content in neem-seed kernels ranged from 0.1 to 0.15%; in commercial neem formulations the content ranged from 200 to 2000 ppm. The method developed may be applied to environmental monitoring of aza and quality assurance studies of aza-based commercial formulations.
Spectrofluorimetric Determination of Vigabatrin and Gabapentin in Dosage Forms and Spiked Plasma Samples Through Derivatization with 4-Chloro-7-Nitrobenzo-2-Oxa-1,3-Diazole
Authors: Hassan Ekram M , Belal Fathalla , Al-Deeb Omar A , Khalil Nasr Y 
Published: February 2020

Abstract
A highly sensitive and specific method is proposed for the determination of vigabatrin (I) and gabapentin (II) in their dosage forms and spiked human plasma. The method is based on coupling the drugs with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole in borate buffer at pH 7.1 and measuring the resulting fluorescence at 532 nm after excitation at 465 nm. The fluorescence intensity was a linear function of the concentration of the drugs over the ranges of 1.3–6.5 and 1.7–8.5 μg/mL for I and II, respectively. Minimum detectability values were 0.54 μg/mL (4.2 × 10−6M) and 0.97 μg/mL (5.7 × 10−6M) for I and II, respectively, under the described conditions. The proposed method was successfully applied to the determination of the 2 drugs in their dosage forms, and the percent recoveries ± standard deviation (SD) were 104.53 ± 1.2 and 100.00 ± 1.32 of the label claim for I and II, respectively. The method was further applied to the determination of vigabatrin in spiked plasma samples. The percent recovery ± SD was 101.58 ± 2.68. Interference from endogenous α-amino acids was overcome through selective complexation with freshly prepared Cu(OH)2. The interference likely to be encountered from co-administered drugs, such as carbamazepine, cimetidine, clonazepam, clopazam, phenobarbital, valproic acid, and lamotrigine, was also studied. A reaction pathway is suggested.
Characterization of Partially Transesterified Poly(β-Hydroxyalkanoate)s by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry
Authors: Saeed Kamal A , Ayorinde Folahan O , Eribo Broderick E , Gordon Michael , Collier Ledelle 
Published: February 2020

Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was used for the characterization of a partially transesterified poly(β-hydroxyalkanoate) (PHA), a polymer produced by the bacterial strain Alcaligenes eutrophus with saponified vegetable oils as the sole carbon sources. The transesterification was carried out separately under acidic and basic conditions to obtain PHA oligomers weighing &lt;10 kDa. The intact oligomers were detected in their cationized forms, [M + Na]+ and and [M + K]+, by MALDI–TOFMS. A composition analysis, using the MALDI-TOF spectra, indicated that the oligomers obtained via acid catalysis contained a methyl 3-hydroxybutyrate end group, and those obtained by base catalysis had a methyl crotonate (olefinic) end group. In addition to hydroxybutyrate (HB), the oligomers were found to contain a small percentage of hydroxyvalerate, which was independently confirmed by gas chromatography/mass spectrometry. In comparison, analysis of a commercial PHA polymer, transesterified under identical conditions, showed only the presence of HB, i.e., a pure poly(HB) homopolymer.
Quantitation of Volatile Oils in Ground Cumin by Supercritical Fluid Extraction and Gas Chromatography with Flame Ionization Detection
Authors: Heikes David L , Scott Brendan , Gorzovalitis Nick A 
Published: February 2020

Abstract
Ground cumin is used as a flavoring agent in a number of ethnic cuisines. The chemical entities, which primarily establish its characteristically pungent flavor, are found in the volatile oil of cumin. Fixed oils and carbohydrates tend to round out the harshness of the volatile oil components. However, the quantity of volatile oil is commonly the measure of the quality of this spice. For several decades, the spice industry has used a classical distillation procedure for the determination of volatile oil in cumin and other spices. However, the method is cumbersome and requires nearly 8 h to complete. Supercritical fluid extraction with capillary gas chromatography–flame ionization detection is utilized in the formulation of a rapid, accurate, and specific method for the determination of volatile oil in ground cumin. Samples are extracted in a static-dynamic mode with CO2 at 550 bar and 100°C. Toluene is used as a static modifier addition. The extracted volatile oil, collected in toluene, is analyzed directly using tetradecane as the internal standard. Integration is performed as grouped peaks to include all chemical entities found in cumin volatile oil recovered from the official distillation procedure. Results from this procedure compare favorably with those obtained by the official procedure (coefficient of correlation = 0.995, 24 samples).
Validation and Quality Assurance of Planar Chromatographic Procedures in Pharmaceutical Analysis
Authors: Ferenczi-Fodor Katalin , Végh Zoltán , Nagy-Turák Anikó , Renger Bernd , Zeller Marco 
Published: February 2020

Abstract
Within the process of the International Conference on Harmonization (ICH), 2 guidelines were released containing a standardized terminology, a verified model of requirements for the validation of analytical procedures, and some guidance in the practical aspects of conducting validation studies in pharmaceutical analysis. For planar chromatographic procedures, which may be used at different levels either in qualitative identity testing, assays, semiquantitative limit tests, or quantitative determination of impurities, this paper tries to transfer these formal requirements into practical approaches for validation. Basic acceptance criteria for evaluation of validation experiments based on practical experience are proposed. In addition, selected parameters for robustness testing of given procedures and quality assurance of quantitative planar chromatographic testing by control charts is described.
Validation of a UV Spectrophotometric Method for the Determination of Melatonine in Solid Dosage Forms
Authors: Pérez Renato F , Lemus Igor G , Bocic Rony V , Pérez Mauricio V , García-Madrid Rubén 
Published: February 2020

Abstract
The aim of the work described in this paper was to provide a fast, easy, inexpensive, precise, and accurate method for the determination of melatonine in solid pharmaceutical dosage forms. The developed method is based on a UV first-derivative spectrophotometric determination, which exhibits excellent linearity in aqueous solutions (r2 = 0.996) for analyte concentrations of 1.5–4.5 mg/dL within a pH range of 5–9. Neither excipients present in the formulation nor indole adulterants, such as tryptophan (up to 5%), interfere with the assay. A study of variation parameters showed that sonication temperature was the main factor for successful determination. At temperatures of &lt;45°C, the sample dissolved completely, and accurate spectrophotometric measurements were obtained. A study was conducted of all the parameters established by the United States Pharmacopeia, 23rd Rev., to validate an analytical method for a solid pharmaceutical form, i.e., linearity, range, accuracy, precision, and specificity. All the parameters were in accordance with the acceptance criteria of the Comité de Guías Oficiales de Validación de la Dirección General de Control de Insumos para la Salud de Méjico. In addition, robustness and content uniformity tests were performed to substantiate the usefulness of the method.
Petrifilm™ Rapid S. aureus Count Plate Method for Rapid Enumeration of Staphylococcus aureus in Selected Foods: Collaborative Study
Authors: Silbernagel Karen M , Lindberg Kathryn G ,   Collaborators:, Ary M , Bannach B , Barbour M , Battista K , Bauten H , Beatty S , Bogar S , Buczek L , Bulthau M , Burnett T , Carver C , Cha K , Cooper L , D’Andrea L , Davis B , Fain A , Feiler B , Fender M , Hirt W , Iannucci M , Jackson J K , Jensen D , Johnson K , Julien-Davis G , Kempf A , Krone P , Kusch S , LaPointe A , Leiva B R , Lewandowski V , Lewis J , Maycock L , Mebs D , McCann T , Moulsoff M , Newcomer C , Ooya M , O’Shea P , Otten N , Reed J , Remes A , Resutek J , Rukamp B , Rukamp S , Saito A , Shafie A , Smith A , Tabatt J , Tanaka H , Torrance H , VandeVoort M , Wang D , Windsor S , Xiong Y , Zebchuck A 
Published: February 2020

Abstract
A rehydratable dry-film plating method for Staphylococcus aureusin foods, the 3M™ Petrifilm™ Rapid S. aureus Count Plate method, was compared with AOAC® Official MethodSM 975.55 (Staphylococcus aureus in Foods). Nine foods—instant nonfat dried milk, dry seasoned vegetable coating, frozen hash browns, frozen cooked chicken patty, frozen ground raw pork, shredded cheddar cheese, fresh green beans, pasta filled with beef and cheese, and egg custard—were analyzed for S. aureus by 13 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample and 3 levels of inoculated test sample, each in duplicate. The mean log counts for the methods were comparable for pasta filled with beef and cheese; frozen hash browns; cooked chicken patty; egg custard; frozen ground raw pork; and instant nonfat dried milk. The repeatability and reproducibility variances of the Petrifilm Rapid S. aureus Count Plate method were similar to those of the standard method.
Detection of Hazelnut Oil in Virgin Olive Oil by Assessment of Free Sterols and Triacylglycerols
Authors: Vichi Stefania , Pizzale Lorena , Toffano Emilio , Bortolomeazzi Renzo , Conte Lanfranco 
Published: February 2020

Abstract
Free sterols were evaluated as factors for discriminating between genuine virgin olive oil and hazelnut-mixed virgin olive oil. Numeric analyses of the results amplified the differences between groups. The application of this method to virgin olive oil samples and their mixtures with 10% hazelnut oil distinguished between genuine and nongenuine virgin olive oil with statistical certainty. Triacylglycerol analysis was tested for the same purpose by using parameter ΔECN42, but although it possessed a discriminating capacity, it alone could not distinguish the aforementioned groups with sufficient certainty. Free Δ7-sterols data were combined with ΔECN42 data into a single discriminating function to improve differentiation and bring more ruggedness, and for detection of low amounts (10%) of hazelnut oil in virgin olive oil. In fact, the values obtained by addition of Δ7-sterol data and ΔECN42 data showed a higher discriminating capacity than single parameters. In a single operation the method produced all the oil fractions necessary for analysis of free sterols and triacylglycerols with ECN42. Solid-phase extraction was applied in substitution of traditional chromatography on a silica column.
Fatty Acid Composition of Chlorella and Spirulina Microalgae Species
Authors: Ötleş Semih , Pire Ruhşen 
Published: February 2020

Abstract
Two New Age foods which contain high concentrations of whole food nutrients are the single-celled microalgae Chlorella and Spirulina. They are accepted as functional foods, which are defined as products derived from natural sources, whose consumption is likely to benefit human health and enhance performance. These foods are used as a supplement/ingredient or as a complete food to enhance the performance and state of the human body, or improve a specific bodily function. Functional foods are used mainly as products to nourish the human body after physical exertion or as a preventive measure against ailments. We determined the fatty acid compositions, particularly polyunsaturated fatty acid compositions, of Chlorella and Spirulina by capillary column-gas chromatography. The data obtained show that Spirulina contains unusually high levels of gamma-linolenic acid, an essential polyunsaturated fatty acid.
Liquid Chromatography/Electrospray Ionization/Isotopic Dilution Mass Spectrometry Analysis of n-(Phosphonomethyl) Glycine and Mass Spectrometry Analysis of Aminomethyl Phosphonic Acid in Environmental Water and Vegetation Matrixes
Authors: Grey Lorna , Nguyen Bick , Yang Paul 
Published: February 2020

Abstract
A liquid chromatography/electrospray/mass spectrometry (LC/ES/MS) method was developed for the analysis of glyphosate (n-phosphonomethyl glycine) and its metabolite, aminomethyl phosphonic acid (AMPA) using isotope-labelled glyphosate as a method surrogate. Optimized parameters were achieved to derivatize glyphosate and AMPA using 9-fluorenylmethyl chloroformate (FMOC-Cl) in borate buffer prior to a reversedphase LC analysis. Method spike recovery data obtained using laboratory and real world sample matrixes indicated an excellent correlation between the recovery of the native and isotope-labelled glyphosate. Hence, the first performance-based, isotope dilution MS method with superior precision, accuracy, and data quality was developed for the analysis of glyphosate. There was, however, no observable correlation between the isotope-labelled glyphosate and AMPA. Thus, the use of this procedure for the accurate analysis of AMPA was not supported. Method detection limits established using standard U.S. Environmental Protection Agency protocol were 0.06 and 0.30 μg/L, respectively, for glyphosate and AMPA in water matrixes and 0.11 and 0.53 μg/g, respectively, in vegetation matrixes. Problems, solutions, and the method performance data related to the analysis of chlorine-treated drinking water samples are discussed. Applying this method to other environmental matrixes, e.g., soil, with minimum modifications is possible, assuring accurate, multimedia studies of glyphosate concentration in the environment and the delivery of useful multimedia information for regulatory applications.
Method of Determination of Appropriate Heat Treatment of Animal Meal by Immunoassay Developed for Detection of Cooked Beef: Interlaboratory Study
Authors: Björklund Erland , Pallaroni Lea , Holst Christoph von , Unglaub Wolfgang ,   Collaborators:, Bosch J , Calderon-Alvarez F , Costa J , Cowles J , Gaede W , Krause M , Marmo S , Pecoraro S , Reaney S , Sutton M , Thiele D , Wolf C 
Published: February 2020

Abstract
An interlaboratory trial was conducted for the validation of an enzyme-linked immunosorbent assay (ELISA) method for determination of appropriate heat treatment of animal meal. A commercially available ELISA test kit developed for the identification of beef in cooked food was used in the study. Twelve laboratories from 7 European countries examined 2 different analytical protocols to establish the most appropriate analytical method. Three different samples were used, 2 animal waste materials sterilized at 129 and 134°C (wet conditions), respectively, and a meat and bone meal material processed at dry conditions (maximum temperature, 140°C). Statistical evaluation applying t-statistics showed that the animal meal treated according to European legislation (&gt;133°C) was clearly distinguishable from the 2 other test materials at a 99% confidence level using both analytical protocols. This method can be considered as a complementary test to the immunoassay developed for the detection of pork in cooked food that is already applied in routine analysis for the surveillance of rendering plants.