bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Iodine in Seafood by Inductively Coupled Plasma/Mass Spectrometry
Authors: Julshamn Kaare , Dahl Lisbeth , Eckhoff Karen 
Published: February 2020

Abstract
A method was developed for determination of total iodine content in different standard reference materials (SRMs) and seafood products by inductively coupled plasma/mass spectrometry (ICP/MS). If iodine is present as iodide and nitric acid is used in the wet digestion system, the observed signal is not stable when iodine is measured by ICP/MS at m/z 127. To stabilize the iodine signal, 3% ammonia solution (1 + 1, v/v) was added to the digest. The limit of quantitation of the method, defined as 6 times the standard deviation in the blank solution (n = 20) was estimated to be 15 mg/kg (using 0.2 g dry mass and a dilution factor of 50). The precision, expressed as repeatability of the iodine concentration, varied between 3.2 and 12% in SRMs, with concentrations of 4.70–0.17 mg/kg dry matter. The described method was compared with a method using tetramethylammonium hydroxide extraction. Both methods showed good precision and trueness by analyses of SRMs. The 2 methods were used to determine iodine in seafood from the Barents Sea, the Norwegian Sea, and the North Sea. The results showed great variation between different fish species as well as between individuals within a species. The lowest values of iodine were recorded in muscle of ling (Molva molva) with a mean of 0.07 mg/kg fresh weight and a variation between 0.03 and 0.11 mg/kg fresh weight. The highest values were found in cod (Gadus morhua) from the Barents Sea, with a mean of 2.5 mg/kg and a variation between 0.7 and 12.7 mg/kg fresh weight.
Determination of Polycyclic Aromatic Hydrocarbons from Buzzards (Buteo buteo) and Tawny Owl (Strix aluco) by Liquid Chromatography with Fluorescence Detection
Authors: Amigo Susana González , Yusty Maria Asunción Lage , Lozano Jesús Simal 
Published: February 2020

Abstract
Supercritical fluid extraction was applied to the determination of naturally contaminated polycyclic aromatic hydrocarbons (PAHs) in bird tissue by liquid chromatography with fluorescence detection (LC-FL). Recoveries (&gt;90%) and relative standard deviations (≤7.7%) were satisfactory. The levels of 10 PAHs were analyzed in 6 classes of tissues (heart, liver, intestine, muscle, lung, and kidney) of 10 buzzards and 2 tawny owls, predatory birds from the Galicia (northwest Spain). The PAHs found most abundantly were pyrene, fluoranthene, benzo[a]anthracene, and anthracene. Chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene were not detected. Intestine, kidney, and lung were more polluted than other tissues.
Simultaneous Liquid Chromatographic Determination of 39 Polycyclic Aromatic Hydrocarbons in Indoor and Outdoor Air and Application to a Survey on Indoor Air Pollution in Fuji, Japan
Authors: Ohura Takeshi , Sugiyama Tomohiko , Amagai Takashi , Fusaya Masahiro , Matsushita Hidetsuru 
Published: February 2020

Abstract
An analytical method was established for the simultaneous determination of 39 polycyclic aromatic hydrocarbons (PAHs) in air. The method was applied to a survey of gaseous and particulate PAHs in household indoor air. The survey was performed in 21 houses in the summer of 1999 and in 20 houses in the winter of 1999–2000 in Fuji, Japan. Thirty-eight PAHs were determined in indoor and outdoor air in the summer, and 39 PAHs were determined in indoor and outdoor air in the winter. The concentrations of gaseous PAHs in indoor air tended to be higher than those in outdoor air in the summer and winter. The concentrations of particulate PAHs in indoor air were the same as or lower than those in outdoor air in the summer and winter. PAH profiles, correlations between PAH concentrations, and multiple regression analysis were used to determine the factors affecting the indoor PAH concentrations. These results showed that gaseous PAHs in indoor air were primarily from indoor emission sources, especially during the summer, and that indoor particulate PAH concentrations were significantly influenced by outdoor air pollution.
Determination of Total Fumonisins in Corn by Competitive Direct Enzyme-Linked Immunosorbent Assay: Collaborative Study
Authors: Bird Chuck B , Malone Bruce , Rice Larry G , Ross P Frank , Eppley Robert , Abouzied Mohamed M ,   Collaborators:, Ashman P , Carpenter N , Drouches M , Fairchild A , Hartman R , Herald S , Holloway S , Horrisberger G , Jackson H , Jones K , Landis K , Leichtweis H , Peden J 
Published: February 2020

Abstract
Fumonisins—mycotoxins produced by some Fusarium species—have been shown to be the causative agent of diseases in horses and other domesticated animals as well as possible carcinogens in humans. A collaborative study was conducted to evaluate the effectiveness of a competitive direct enzyme-linked immunosorbent assay (CD-ELISA) for the determination of total fumonisins (B1, B2, and B3) in corn. The test portion was extracted with methanol–water (7 + 3), filtered, diluted, and tested on the CD-ELISA. Naturally and artificially contaminated corn test portions were sent to 13 collaborators in the United States. Naturally contaminated field test portions were prepared at 3 different levels. Artificially contaminated test portions were spiked at 1.0, 3.0, and 5.0 mg/kg total fumonisins (B1, B2, and B3). Average recoveries of total fumonisins were 120, 100, and 90%, respectively. The relative standard deviations for repeatability ranged from 13.3 to 23.3% and the relative standard deviations for reproducibility ranged from 15.8 to 30.3% across all levels tested. HORRAT values, calculated for each individual sample, ranged from 1.24 to 1.94. This method demonstrated acceptable intra- and interlaboratory precision at the levels tested.
Determination of Vitamins A (Retinol) and E (alpha-Tocopherol) in Foods by Liquid Chromatography: Collaborative Study
Authors: DeVries Jonathan W , Silvera Karlene R ,   Collaborators:, Al-Hasani S , Alfiere J , Berge C , Boerner C , Cardozo S , Chettiar M , Dupont K , Gustafson K , Hanson E , Kazeminy A , Krueger D , Mazal R , Meland P , Mioc B , Oehrl L , Vinski E , Willis D , Wittrig B 
Published: February 2020

Abstract
A collaborative study was conducted for the determination of vitamins A and E. Existing AOAC liquid chromatographic (LC) methods are suited for specific vitamins A and E analytical applications. This method differs from existing methods in that it can be used to assay samples in all 9 sectors of the food matrix. Standards and test samples are saponified in basic ethanol–water solution, neutralized, and diluted, converting fats to fatty acids and retinol esters and tocopherol esters to retinol and tocopherol, respectively. Retinol and alpha-tocopherol are quantitated on separate LC systems, using UV detection at 313 or 328 nm for retinol, and fluorescence detection (excitation 290 nm, emission 330 nm) for alpha-tocopherol. Vitamin concentrations are calculated by comparison of the peak heights or peak areas of vitamins in test samples with those of standards.
Method Extension Study to Validate Applicability of AOAC Official Method 997.03 Visual Immunoprecipitate Assay (VIP®) for Listeria monocytogenes and Related Listeria spp. from Environmental Surfaces: Collaborative Study
Authors: Feldsine Philip T , Lienau Andrew H , Leung Stephanie C , Mui Linda A ,   Collaborators:, Aguilar G , Aharchi J , Aldridge I , Arling V , Bitner B , Bullard C , Carlson P , Cox C , Deiss K , Dillon J , Dombroski P , Ellingson J , Fitzgerald S , Forgey R , Gailbreath K , Gallagher D , Geftman V , Herbst K , Hillis P , Johnson M , Koch S , Lewis D , Luepke J , Martensen D , McDonagh S , McGovern B , Moon B , Moreland L , Murray L , Richter D , Robertson M , Rogers P , Rucker C , Sacca J , Siu M-C , Smith C , Smith J , Stoltzfus E , Summers C , Taylor B , Toth J , Vess R , White S , Witt J-L , Young S 
Published: February 2020

Abstract
Test portions from 3 environmental surface types, representative of typical surfaces found in a food production facility, were analyzed by the Visual Immunoprecipitate assay (VIP®) and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) culture method for Listeria monocytogenes and related Listeria species. In all cases, naturally contaminated environmental test samples were collected from an actual food production facility by sponge or swab. Test samples from concrete surfaces were collected by both swab and sponge; sponge test samples were collected from rubber surfaces, and swabs were used to sample steel surfaces. Test portions from each surface type were simultaneously analyzed by both methods. A total of 27 laboratories, representing government agencies as well as private industry in both the United States and Canada, participated in the study. During this study, a total of 615 test portions and controls was analyzed and confirmed, of which 227 were positive and 378 were negative by both methods. Nine test portions were positive by culture, but negative by the VIP. Five test portions were negative by culture, but positive by the VIP. Four test portions were negative by VIP and by culture, but confirmed positive when VIP enrichment broths were subcultured to selective agars. The data reported here indicate that the VIP method and the USDA/FSIS culture method are statistically equivalent for detection of L. monocytogenes and related Listeria species from environmental surfaces taken by sponges or swabs.
Cleanup Procedure for Determination of Aflatoxins in Major Agricultural Commodities by Liquid Chromatography
Authors: Sobolev Victor S , Dorner Joe W 
Published: February 2020

Abstract
A simple, fast, reliable, and inexpensive chemical cleanup procedure was developed for quantitation of aflatoxins in major important agricultural commodities by liquid chromatography (LC). Aflatoxins were extracted from a ground sample with methanol–water (80 + 20, v/v), and after a single cleanup step on a minicolumn packed with basic aluminum oxide, they were quantitated by LC equipped with a C18 column, photochemical reactor, and fluorescence detector. Water–methanol–1-butanol (1400 + 720 + 25, v/v/v) served as the mobile phase. Recoveries of aflatoxins B1, B2, G1, and G2 from peanuts spiked at 5.0, 2.5, 7.5, and 2.5 μg/kg were 87.2 ± 2.3, 82.0 ± 0.8, 80.0 ± 1.8, and 80.4 ± 2.8%, respectively. Similar recoveries, precision, and accuracy were achieved for corn, cottonseed, almonds, Brazil nuts, pistachios, and walnuts. The quantitation limit for aflatoxin B1 was 1 μg/kg. The minimal cost of the minicolumn allows for substantial savings compared with available commercial aflatoxin cleanup devices.
Quantitative LC/MS-MS Determination of Sulfonamides and Some Other Antibiotics in Honey
Authors: Kaufmann Anton , Roth Sven , Ryser Bianca , Widmer Mirjam , Guggisberg Dominik 
Published: February 2020

Abstract
A simple and rapid method was developed for the determination of 20 antibiotics (sulfonamides, tetracyclines, and flumequine) in honey by liquid chromatography tandem mass spectrometry. The proposed method is sensitive (limit of detection 0.5 to 10 ppb for the various antibiotics) and selective. A hydrolysis step ensures the liberation of sugar-bound sulfonamides. The approach has been used to analyze some 300 honey samples. A number of them were found to have exceeded the Swiss limit of 50 ppb.
Liquid Chromatographic Determination of Ampicillin Residues in Porcine Muscle Tissue by a Multipenicillin Analytical Method: European Collaborative Study
Authors: Verdon Eric , Couëdor Pierric , Maris Pierre , Laurentie Michel ,   Collaborators:, Batjoens P , Brady B , Branzell C , Csokan P , Da Silva I , Degroodt J M , Edder P , Gomes M N N H , Kennedy D G , Keukens H , Kraus M , Lindfors E , Martin de Pozuelo M , Moretain J P , Orntoft I , Österdahl B G , Rasmussen A , Regan L , Reuvers Th , Roudaut B , Satarzadeh M , van Rhijn J A 
Published: February 2020

Abstract
A collaborative study involving 14 laboratories was conducted to determine residues of ampicillin in porcine muscle tissue by using a liquid chromatographic method developed for multipenicillin analysis that can quantitate 8 penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, nafcillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in muscle tissue. This method involves extraction of the penicillins with phosphate buffer, pH 9, followed cleanup and concentration on a C18 solid-phase extraction column and reaction with benzoic anhydride at 50°C and with 1,2,4-triazole and mercury(II) chloride solution, pH 9.0, at 65°C. The derivatized compounds are eluted isocratically on a C8 column with a mobile phase of acetonitrile and phosphate buffer (pH 6; 0.1M) containing sodium thiosulfate and the ion-pair reagent tetrabutylammonium hydrogen sulfate. The penicillins are detected by UV absorption at 325 nm. The limit of detection and the limit of determination (quantitation) of the method were calculated to be approximately 3–5 and 25 μg/kg, respectively, in accordance with the criteria of European Union (EU) Decision No. 93/256/EEC. In this first interlaboratory study, collaborators were instructed to monitor 4 different penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, and amoxicillin) by analyzing 8 blind samples of muscle tissue in triplicate. These samples were prepared from 2 materials containing different concentrations of incurred ampicillin (63.5 μg/kg for material No. 1 and 358.1 μg/kg for material No. 2) and 1 blank material. The repeatability relative standard deviation and the reproducibility relative standard deviation were 10.2 and 17.4%, respectively, for material No. 1 and 7.0 and 16.0%, respectively, for material No. 2. These results demonstrate that the method is suitable for the determination of ampicillin residues in muscle tissue at the EU maximum residue limit (50 μg/kg) and above. However, the identification of positives by this procedure may need additional confirmation by techniques with greater specificity, such as liquid chromatography combined with mass spectrometry, or tandem mass spectrometry. Investigations regarding the basis of interlaboratory testing studies will further demonstrate the suitability of multiresidue methodology for detecting and quantitating other compounds in the family of penicillin antibiotics.
Visual Immunoprecipitate Assay Eight Hour Method for Detection of Enterohemorrhagic Escherichia coli O157:H7 in Raw and Cooked Beef (Modification of AOAC Official Method 996.09): Collaborative Study
Authors: Feldsine Philip T , Kerr David E , Leung Stephanie C , Lienau Andrew H , Moser Ruth F , Mui Linda A ,   Collaborators:, Anderson G , Beasley M , Clements S , Dillon J , Dombroski P , Forgey R , Gartside S , Hernandez C , Hopkins S , Johnson K , Meier J , Nguyen T , Ortega R , Reynolds J , Smith J , Solis D , Summers C , Terry J , Tuncan E , Vrana D , Warren W , Wood S 
Published: February 2020

Abstract
AOAC Official Method 996.09, Visual Immunoprecipitate Assay (VIP®) for Escherichia coli O157:H7, was modified to incorporate a new enrichment protocol using BioControl EHEC8™ medium for testing raw and cooked beef. Foods were tested by VIP assay and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) enrichment procedure and the FDA Bacteriological Analytical Manual (BAM) isolation and confirmation techniques. A total of 15 collaborators participated. Raw and cooked ground beef were inoculated with E. coli O157:H7 at 2 different levels: a high level, where predominantly positive results were expect d, and a low level where fractional recovery was anticipated. Collaborators tested 396 test portions and controls by both methods, for a total of 792 test portions. Of the 396 paired test portions, 75 were positive and 230 were negative by both the VIP and culture methods. Eleven test portions were presumptively positive by VIP and could not be confirmed culturally; 32 were negative by VIP, but confirmed positive by culture; and 65 were negative by the culture method, but confirmed positive by the VIP method. There was no statistical difference between results obtained with the VIP for EHEC 8 h method and the culture method except for cooked beef, where the VIP had significantly higher recovery for one inoculation level.
N-Nitroso Compounds and Mutagens in Chinese Fermented (Sour) Corn Pancakes
Authors: Groves Frank D , Issaq Haleem , Fox Stephen , Jeffrey Alan M , Whysner John , Zhang Lian , You Wei-Cheng , Fraumeni Joseph F 
Published: February 2020

Abstract
Stomach cancer rates in rural Linqu County, Shandong Province, China, are exceptionally high. A previous case-control study revealed that the risk of stomach cancer was 30%higher among those who consumed sour (fermented) corn pancakes at least daily. A previous study of the sour pancakes reported volatile nitrosamines in most specimens, and almost half reportedly showed mutagenic activity. Few households currently consume sour pancakes, and the duration of fermentation has been shortened. We tested specimens of pancake batter and sour pancakes from Linqu County for mutagenic activity using the Ames test; for N-nitroso compounds (NOC) we used the Nitrolite–thermal energy analysis (TEA) method. Results of the Ames test were inconclusive: only 1 out of 15 cooked pancakes showed a positive mutagenic response, and all 15 batter specimens were negative; however, several batter specimens showed a weakly positive trend of mutagenicity with extract concentration. Our assay for total nitroso compounds was weakly positive in only 1 out of 15 specimens of sour pancake batter. That specimen was also tested by gas chromatography–TEA for nitrosaminoacids and volatile nitrosamines, but none were detected. It seems unlikely that the Chinese sour pancakes are significantly contaminated by NOC or other mutagens.
Measurement of Resistant Starch by Enzymatic Digestion in Starch and Selected Plant Materials: Collaborative Study
Authors: McCleary Barry V , McNally Marian , Rossiter Patricia ,   Collaborators:, Aman P , Amrein T , Arnouts S , Arrigoni E , Bauer L , Bavor C , Brunt K , Bryant R , Bureau S , Camire M E , Champ M , Chen Q , Chin M-L , Colilla W , Coppin J , Costa D , Crosby G , Dean J , De J. Berrios J , de Valck J , Doerfer J , Dougherty M , Eybye K , Fahey G , Femenia A , Forssell P , Gelroth J , Geske J , Hidaka H , Isaksen M F , Kettlitz B , Kozlowski F , Laerke H N , Li B , Lincoln Y , Liu Q , Martensson A-C , Mattys S , Meuser F , Monro J , Niba L , Niemann C , Panozzo J , Rossiter P , Roturier J-M , Sampson C , Sanders P , Suter D , Tas A A , Themeier H , Tudorica C , Watson R , Weber L , Weinstein M , Wilkinson M , Yen J , Zheng T 
Published: February 2020

Abstract
Interlaboratory performance statistics was determined for a method developed to measure the resistant starch (RS) content of selected plant food products and a range of commercial starch samples. Food materials examined contained RS (cooked kidney beans, green banana, and corn flakes) and commercial starches, most of which naturally contain, or were processed to yield, elevated RS levels. The method evaluated was optimized to yield RS values in agreement with those reported for in vivo studies. Thirty-seven laboratories tested 8 pairs of blind duplicate starch or plant material samples with RS values between 0.6 (regular maize starch) and 64% (fresh weight basis). For matrixes excluding regular maize starch, repeatability relative standard deviation (RSDr) values ranged from 1.97 to 4.2%, and reproducibility relative standard deviation (RSDR) values ranged from 4.58 to 10.9%. The range of applicability of the test is 2–64% RS. The method is not suitable for products with &lt;1% RS (e.g., regular maize starch; 0.6% RS). For such products, RSDr and RSDR values are unacceptably high.
Determination of Ciprofloxacin with a Room-Temperature Phosphorescence Flow-Through Sensor Based on Lanthanide-Sensitized Luminescence
Authors: Cuenca-Trujillo Rosa M , Ayora-Cañada M José , Molina-Díaz Antonio 
Published: February 2020

Abstract
Direct measurement of the sensitized luminescence of the europium-ciprofloxacin chelate immobilized on a cationic exchanger was used to develop a flow-through room-temperature phosphorescence optosensor for determination of ciprofloxacin. The phosphorescent chelate is formed on-line at room temperature in a flow-injection system and is immobilized on a weakly acidic cation-exchange resin packed in a flow cell. Optimum experimental conditions and analytical performance are discussed in detail. The sensor response for ciprofloxacin was linear, from 1.5 × 10−6 to 2.0 × 10−5M with a relative standard deviation of 2.5% (n = 10) and a detection limit of 1.1 × 10−7M. The effect of possible interferences on sensor response was studied. The sensor was successfully tested for the determination of ciprofloxacin in pharmaceutical formulations.
Determination of Nitrogen Solubility in Dilute Pepsin Hydrochloric Acid Solution of Fishmeal: Interlaboratory Study
Authors: Miller Eric L , Bimbo Anthony P , Walters David E , Barlow Stuart M , Sheridan Berni ,   Collaborators:, Abarca I , Araos M , Batieste K M , Benios C J , Broden A , Butler B H , Caquilpan R , Cotton G , Gísladóttir G , Hernández B , Kinnari J , Marrou R , New F , Schulze C W , Sieh J , Solar M G , Sulca B , Timme E 
Published: February 2020

Abstract
A revised method to determine solubility of nitrogen in dilute pepsin, using 0.0002% pepsin in place of 0.2% in AOAC Official Method 971.09, was tested in 16 laboratories with 12 samples of fishmeal. Results were calculated according to 2 procedures: AOAC Official Method 971.09 and a method described in 1964 by researchers at the Torry Research Station (Aberdeen, Scotland), and generally referred to as the modified Torry method. Variations in the method of shaking and source of pepsin were also investigated. Pepsin solubility values were lower and more variable when calculated by the Torry procedure. The method of shaking apparently affected the result when calculated according to the Torry but not the AOAC method. The source of pepsin had no significant effect on between-laboratory variability, but a comparison of the 2 main sources within one laboratory resulted in highly significant differences. Based on this study, the International Fishmeal and Fish Oil Organization has adopted this new method, using 0.0002% pepsin but keeping the AOAC method of calculation. The type of shaker and source of pepsin are recommended but are not mandatory. The repeatability and reproducibility limits of this new method are 1.6 and 3.3% units of solubility, respectively.