bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity of Cultured Human and Mouse Fibroblasts to Trichothecenes
Authors: Abbas Hamed K , Shier W Thomas , Mirocha Chester J 
Published: February 2020

Abstract
Cultured human diploid fibroblasts and a cloned permanent line of Swiss mouse fibroblasts (3T3) have been adapted to a biological assay of trichothecenes and other toxic fungal metabolites both in purified form and as crude extracts. The assays are carried out in multi-well tissue culture trays with serial dilutions of toxins in 200 μL volumes of medium. Cells are cultured with the toxins for 3–4 days, fixed, and stained, providing a permanent record of results. The sensitivity of the assay ranges from 0.1 ng/mL (20 pg/assay) for T-2 toxin on mouse fibroblasts to no detectable toxicity at 5 μg/mL for cis-zearalenone and verrucarol. Human skin fibroblasts exhibit patterns of relative sensitivities similar to that observed with mouse fibroblasts, but the absolute sensitivities are much greater with mouse fibroblasts because they can be cultured at much lower cell densities.
Simultaneous Thin Layer Chromatographic Determination of Aflatoxin B1 and Ochratoxin A in Black Olives
Authors: Le Tutour Bernard , Tantaoui-Elaraki Abdelrhafour , Aboussalim Abdelhadi 
Published: February 2020

Abstract
A screening method has been developed for simultaneous determination of aflatoxin B1 and ochratoxin A in black olives. The technique includes extraction of both mycotoxins with aqueous methanol, cleanup using lead acetate, defatting with hexane, partitioning in chloroform, and thin layer chromatography. Detection limits are 5–7 μg aflatoxin B1 and 20 μg ochratoxin A/kg.
Specific Determination of α-Tocopherol in Food and Feed by Fluorometry. Part 1. Manual Method
Authors: Bourgeois Claude E , Pages Philippe S , Czornomaz Anne M , Albrecht Michel J , Cronenberger Lucien A , George Philippe R 
Published: February 2020

Abstract
The proposed fluorometric method for determining α-tocopherol is highly specific and sensitive, yet requires low-cost equipment available in any laboratory. It is robust and fairly fast (4 determinations in 100 min, sample preparation not included). It has been tested in parallel with a conventional thin layer chromatographic method on foods and feeds. The only necessary cleanup is the usual saponification. The unsaponifiable fraction can be extracted with ethyl ether or, preferably, with Extrelut columns. Isooctane is used as a carrier solvent. Reagents and their solvents are added to the isooctane solution before each successive reaction and are then eliminated by partition with water. The α-tocopherol (α-T) derivative always remains in isooctane. The first step is nitrosation and elimination of tocopherols and tocotrienols other than α-isomers. α-T is then oxidized to α-tocored (α-TR) with a mixture of sulfuric acid, ferric chloride, and iodine bromide. α-TR is then condensed to a new reagent: 4,5-dimethyl-o-phenylenediamine. The phenazine formed is strongly fluorescent. Iodine and bromine add to the double bonds of α-tocotrienol present and quench the fluorescence of its phenazine. A procedure for blank assays specifically inhibits the conversion of α-T to α-TR.
Convection Oven Determination of Loss of Mass on Drying of Quick Frozen French Fried Potatoes: Collaborative Study
Authors: Biltcliffe David O , Judd Hillary J , Wood Roger ,   Collaborators:, Bushnell A C , Crudington R , Evans R A , Fawcett R , Grange C N , Griffiths W , Hall P S , Harrison A J , Kidman S L , Meadows G , Reynolds S , Rymer T E , Shelton J H 
Published: February 2020

Abstract
A collaborative study was carried out on one of the methods submitted to the Joint Economic Commission for Europe (ECE)/Codex Alimentarius Commission Group of Experts on the Standardization of Quick Frozen Foods for the determination of moisture in quick frozen french (fried potatoes. The method was based on the determination of loss of mass of the sample on drying in a convection oven 16 h at 103±2°C. Two samples of uncooked quick frozen french fried potatoes and 2 samples of oven quick frozen french fried potatoes were analyzed by 14 and 13 laboratories, respectively. The method is simple and was found to be analytically satisfactory with repeatability and reproducibility values of 0.21 and 2.00 g/100 g french fried potatoes, and 0.29 and 3.00 g/100 g oven french fried potatoes, respectively. The method was adopted by the Group of Experts in preference to other proposed procedures for this determination. The method has been adopted official first action by AOAC.
Enzymatic-Ultraviolet Method for Measuring Lactose in Milk: Collaborative Study
Authors: Biltcliffe David O , Kleyn Dick H , Trout J Richard ,   Collaborators:, Azzara D , Bissonette J , Bradley R , Brown R , Chamberlin W , Cheryan M , Dimick R , Duthie A , Fox J , Sherbon J , Somkuti G , Zimmerman A 
Published: February 2020

Abstract
Collaborators in 8 dairy and food industry laboratories performed one lactose determination on each of 8 unknown samples of milk, lowfat milk, or skim milk, as 3 pairs of blind duplicates. Two known samples were provided to gain experience prior to analysis of the unknown samples. All of the above samples were also analyzed for lactose content by the official AOAC gravimetric method (16.507) by a commercial laboratory. From the overall mean of results on all samples, determinations by the enzymatic method averaged 0.49% lower than by the AOAC method. This difference was significant by the t-test (P = 0.05), which indicated a lack of agreement between the compared methods in determining lactose content. Standard deviations were similar for the 3 sets of blind duplicates which ranged between 3.67 and 4.55% lactose content. F-values revealed that variations between means obtained by laboratories differed significantly as compared with variations within laboratory means. The method has been adopted official first action.
Simplified Method for Liquid Chromatographic Determination of Carbofuran in Soils
Authors: Lauren Denis R 
Published: February 2020

Abstract
A simple, direct method is described for determining carbofuran (CF), 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate, in soils. Methanol extraction is followed by hexane–methanol–water (2 + 4 + 1) partition and liquid chromatographic analysis of the aqueous layer with UV detection at 280 nm. The method specifies dilution of the partitioned extract with water to methanol–water (20 + 80), and injection of 1000 μL sample volumes. This technique allowed a 10-fold increase in sensitivity over direct injection from the partition step. Recovery of CF by the method is about 90%, and less than 0.4 μg CF/ g soil can be detected at a medium detector sensitivity of 0.04 AUFS.
Liquid Chromatographic Analysis System for Cyclopiazonic Acid in Peanuts
Authors: Lansden John A 
Published: February 2020

Abstract
A liquid chromatographic procedure has been developed for analysis of cyclopiazonic acid in peanuts. The chromatographic system specifies a C18 or C8 column loaded with 4-dodecyldiethylenetriamine and an aqueous mobile phase containing 4-dodecyldiethylenetriamine, zinc acetate, ammonium acetate, 2-propanol, and acetonitrile. Cyclopiazonic acid was extracted from peanuts with methanol-chloroform (20 + 80), partitioned into aqueous sodium bicarbonate, acidified, and back-extracted into dichloromethane. The limit of detection (280 nm UV) was approximately 4 ng and detector response was linear to at least 1 μg pure cyclopiazonic acid. The recovery of cyclopiazonic acid from peanuts spiked at 68.9, 210, and 955 μ/kg was 85.9% (12.86% CV), 72.9% (6.43% CV), and 81.4% (0.40% CV), respectively. Calculation of the chromatographic peak parameters based on the exponentially modified Gaussian model indicated that the C18 column produced less peak skewing than did the C8 column.
Short Liquid Chromatographic Method for Determination of Zearalenone and alpha-Zearalenol
Authors: Chang Henry L , Devries Jonathan W 
Published: February 2020

Abstract
A rapid method has been developed for the determination of zearalenone and alpha-zearalenol, using liquid-liquid partition for sample extract cleanup followed by liquid chromatography (LC) with fluorescence detection. The same extract can also be used for determination of aflatoxin by LC. Relative standard deviations for the method based on duplicate analyses are 4.18% for artificially contaminated samples and 13.92% for naturally contaminated samples. The method was compared with the AOAC method of extraction and column chromatography extract cleanup, using the same LC conditions for quantitation for both methods. Results showed a correlation coefficient of 0.990 with a mean zearalenone content by this method of 987.8 ppb, and 732.6 ppb by the official AOAC method. The detection limit of this method is 2.2 ppb for zearalenone and 1.5 ppb for alpha-zearalenol.
Recovery of Salmonella Species from Nonfat Dry Milk Rehydrated Under Rapid and Reduced Pre-enrichment Conditions: Collaborative Study
Authors: Poelma Paul L , Andrews Wallace H , Wilson Clyde R ,   Collaborators:, Bennett B , Elliot P H , Estela L A , Flowers R , Jogan M J , Lancette G A , Liddle K , Mastrorocco D A , McDonald R L , Moran A , Morrison D L , Noah C W , Okrend A , Roberts B , Romick T , Ruby R M , Sherman G , Singleton E R , Smith T , Sveum W H , Wagner C A , Wagner D E , Zipkes M R 
Published: February 2020

Abstract
A collaborative study was conducted to compare the relative efficiency of the AOAC rapid rehydration method with the reduced rehydration soak method for the recovery of Salmonella species from nonfat dry milk (NFDM). In the AOAC method, a 25 g sample of NFDM is rapidly rehydrated at a 1:9 sample/water ratio and mixed by swirling. After 60 min, the flask contents are adjusted to a pH of 6.8, and 0.45 mL of 1% aqueous brilliant green dye solution is added. The flasks are then incubated at 35°C. In the soak method, a 25 g sample of NFDM is gently added to the sterile brilliant green (BG) water at a 1:9 sample/ BG water ratio and allowed to soak undisturbed for 60 min at room temperature before incubation. Twelve collaborators analyzed 3 shipments of samples with the following results for the AOAC and soak methods: shipment 1—31 and 46 positive samples, respectively, with a 48% increase in detection by the soak method; shipment 3-45 and 66 positive samples, respectively, with a 47% increase in detection by the soak method; shipment 2—no significant difference in recovery of Salmonella species by the 2 methods. It is recommended that the official final action method for the detection of Salmonella species, 46.054- 46.067, be revised to use the soak method for the analysis of nonfat dry milk.
Enumeration of Total Coliforms, Fecal Coliforms, and Escherichia coli in Foods by Hydrophobic Grid Membrane Filter: Collaborative Study
Authors: Entis Phyllis ,   Collaborators:, Bennett B , Brodsky M H , Burgener D M , Carlson V L , Carson M , Catherwood K , Ciebin B S , Cox N A , Dahiya R S , Daley H , Devenish J , Erickson J , Fettig P , Foster R , Gorski J , Hall P A , Hunt S D , Jagow J , Jenkins P , Jordan P R , Krieger F , Kwan P , Lanier J M , Liliard H S , Martin A , Milling M E , Nakanishi H , Nath E , Oggle J , Okrend A , Pongchairerks V , Posey D , Rodriguez J , Rose B E , Sayfie J , Taylor C , Teramoto T , Vandellen E 
Published: February 2020

Abstract
A collaborative study was conducted in 18 laboratories to assess the performance of the hydrophobic grid membrane filter method against that of the AOAC official first action method 46.013-46.016 for enumerating total and fecal coliforms and Escherichia coli. The study was carried out on frozen breaded fish, raw comminuted poultry, unroasted walnut pieces, ground black pepper, and cheddar cheese. The hydrophobic grid membrane filter method recovered significantly larger numbers of target bacteria in 7 of the food/analysis combinations: fecal coliforms in fish; E. coli in poultry; fecal coliforms and E. coli in walnuts; and total coliforms, fecal coliforms and E. coli in black pepper. Random error (Sr2) associated with the hydrophobic grid membrane filter method was significantly lower than that of the reference method in over 30% of the paired sample series. The hydrophobic grid membrane filter method for total coliform, fecal coliform, and E. coli enumeration in foods has been adopted official first action.
Gas Chromatographic Determination of Fenvalerate Insecticide Residues in Processed Tomato Products and By-Products
Authors: Spittler Terry D , Argauer Robert J , Lisk Donald J , Mumma Ralph O , Winnett George , Ferro David N ,   Collaborators:, Bogus E , Greco E , Gutenmann W , Miles E , Simmons K , Walton J , Zimmerman L 
Published: February 2020

Abstract
The results of a 5-laboratory collaborative determination of residues of the synthetic pyrethroid insecticide fenvalerate in tomato products are presented. Tomatoes from plants treated in the field at 2-4 day intervals (13 foliar applications) were processed into chopped fresh tomatoes, canned quarters, juice, paste, and the by-product skins plus seeds. Gas chromatographic analysis of the commodities for fenvalerate showed the fresh produce to contain 0.26 ppm, and the skins plus seeds contained 1.9 ppm. Residues were barely detectable in canned peeled quarters and juice, but averaged 0.12 ppm for paste, the concentration product of juice. High residues were associated with the skin content of the product. Five laboratories using modifications of the same analytical technique obtained good collaborative agreement.
Identification and Semiquantitation of Monensin Sodium in Liver Tissue
Authors: Martinez Elizabeth E , Shimoda Wilbert 
Published: February 2020

Abstract
A bioautographic technique for the determination of monensin sodium in animal feed has been applied to chicken and beef liver tissues. The reliable limit of sensitivity is 100 ppb, but 10 ppb can be detected. This technique can be used to semiquantitate monensin in tissues by comparing the zones of inhibition of unknown test samples against monensin standards.
Elimination of Aliquoting in Automated Flame Photometric Determination of K2O in Fertilizers
Authors: Steele Layna D , Ramsey Kelly J , Kane Peter F 
Published: February 2020

Abstract
Current automated instrument systems used in conjunction with the official AOAC flame photometric method for K2O in fertilizer, 2.D06, all require a dilution step to bring the fertilizer extract to the appropriate concentration range. Two CFA (Continuous Flow Analysis) automated instrument systems are described which together eliminate aliquoting over the full range of fertilizer potassium, a significant saving of analyst effort if large numbers of samples are analyzed. The systems have performance characteristics well within the limits in the official method, and produce results comparable to current methods on routine samples.
Rapid Determination of Color Additives, Using the C18 Cartridge
Authors: Young Mary L 
Published: February 2020

Abstract
A reliable method has been developed for the rapid separation and identification of the 7 permitted FD&C dyes (Red Nos. 3 and 40; Blue Nos. 1 and 2; Yellow Nos. 5 and 6; Green No. 3) and the recently banned FD&C Red No. 2 in foods. The colors are separated by using the C18 cartridge, and their identity is confirmed by spectrophotometry.
Modified Flotation Technique for Quantitative Determination of Mite Populations in Feedstuffs
Authors: Thind Bharat B , Wallace David J 
Published: February 2020

Abstract
Modifications are described to a previously published technique for quantitative determination of mite populations in animal feedingstuffs. In the modified method, the oil phase is kerosene instead of a mixture of kerosene and tetralin (1 + 1), and aqueous industrial methylated spirit is substituted for aqueous ethanol in the aqueous phase. Emulsion formation at the interface is considerably reduced by incorporating a pre-extraction stage. Examination of mites on the filter paper is made easier and quicker by staining them with Phloxin B. Trials carried out with known numbers of mites in samples of dairy feed concentrates indicate mean recoveries of 84-96% throughout the range tested. The results show that the accuracy of the technique is not affected by the level of infestation.
Comparison of HgO and CuS04 as Digestion Catalysts in Manual Kjeldahl Determination of Crude Protein in Animal Feeds: Collaborative Study
Authors: Kane Peter F ,   Collaborators:, Altemeier A , Austin L L , Beggs C V , Cathey R D , Grant R , Hester J B , Hudson S , Johnson W C , Krause J , Midkiff V , Morris H F , Mueller E E , O’Neil M , Perry W V , Smith R D , Stedman R , Steele L D , Tulloch R N , VanDeKoppel G , Vickery R M , Willkens G , Williams D C 
Published: February 2020

Abstract
The official AOAC manual Kjeldahl method for determining crude protein in animal feeds, 7.015, uses HgO as a catalyst in the digestion step. Because of environmental considerations, there is considerable interest in alternative catalysts. A collaborative study compares the official HgO-catalyzed method and an alternative using CuS04. Fifty-four samples consisting of blind duplicates of closely matched pairs, representing a range of animal feed materials and 2 standard materials, were analyzed once by each method. Results were returned by 22 laboratories. Means and standard deviations between methods were comparable. The CuS04-catalyzed method has been adopted official first action.
Liquid Chromatographic Determination of Acetic Acid in Foods
Authors: Ashoor Samy H , Welty Jim 
Published: February 2020

Abstract
A liquid chromatographic (LC) method has been developed for the determination of acetic acid in vinegar and other foods. The LC system includes an Aminex HPX-87H column and a UV detector set at 210 nm. The mobile phase is 0.009N H2S04 at a flow rate of 0.7 mL/min. The method is simple and specific for acetic acid. Recoveries of acetic acid from a variety of products ranged from 93.3 to 102% with coefficients of variation from 2.4 to 4.6%.
Identification of a Propantheline Analog in Propantheline Bromide Tablets
Authors: Ford Bruce L , Wall Andrew K , Johnston Michael A , Lea Anthony R 
Published: February 2020

Abstract
A major impurity in a sample of propantheline bromide tablets has been identified as 9-hydroxypropantheIine on the basis of the proton magnetic resonance (PMR) and mass spectra (MS). This identification was confirmed by methanolysis of the tablet extract, which yielded a mixture of methyl xanthanoate and methyl 9-hydroxyxanthanoate. A liquid chromatographic (LC) procedure is described which will permit quantitation of 9-hydroxypropantheline bromide in the presence of propantheline bromide, xanthone, and xanthanoic acid.
Detection of Escherichia coli Enterotoxins by Using Mouse Adrenal Cell and Suckling Mouse Assays: Collaborative Study
Authors: Lovett Joseph , Peeler James T ,   Collaborators:, Boutin B K , Cholensky J S , Edwards A W , Ferreira J L , Hunt J M , Kaysner C A , O’Brien K , Ruby R M 
Published: February 2020

Abstract
The ability of 10 Escherichia coli strains to produce heat-stable enterotoxin (ST) and heat-labile enterotoxin (LT) was determined by 8 analysts in a collaborative study. The suckling mouse model and the mouse adrenal cell line (Y-l) tests were used to detect ST and LT, respectively. Cultures for assay were grown 24 h in casamino acid-yeast extracttrace salts broth at 37°C in a shaker incubator at 250 rpm. Cell-free culture broth prepared by centrifugation and filtration was divided into 2 portions: One was heated for 30 min and used both for ST assay and as a heated control for LT assay; the other was used unheated for LT assay. Results were expressed as positive for ST, positive for LT, positive for ST and LT, or negative for both ST and LT; percent of correct estimates was calculated for each culture for each analyst. At the 95% confidence interval, the overall correct results were 96.3 ± 2.9 and 95.0 ± 3.4% for ST and LT, respectively. The test performances thus were satisfactory for detecting ST and LT produced in vitro by E. coli. The method has been adopted official first action.
Liquid Chromatographic Determination of Carbadox, Desoxycarbadox, and Nitrofurazones in Pork Tissues
Authors: Macintosh Agnes I , Neville George A 
Published: February 2020

Abstract
A liquid chromatographic (LC) method has been developed for the determination of carbadox, desoxycarbadox, and nitrofurazones in the 10-40 ppb range in pork muscle, liver, and kidney tissues. Tissues were homogenized in absolute ethanol, and the homogenates were treated with metaphosphoric acid and reduced in volume by rotovaporization. Hexane was added to the concentrates, which were then centrifuged to remove fat. After addition of KH2P04 to the aqueous phase and extraction with ethyl acetate, the extracts were passed through alumina columns before analysis by reverse phase LC. Overall average recoveries (10-40 ppb range) for carbadox and desoxycarbadox from spiked tissues were 53% ± 13.6 and 61% ± 7.2, respectively; overall average recoveries for nitrofurazone and furazolidone were 43% ± 7.3 and 77% ± 10.9, respectively. Before these optimum determinations, degradation by even minimal incandescent light was found to reduce recovery especially of desoxycarbadox. The results of this photochemical degradation are reported and briefly discussed.
Rapid Quantitation and Confirmation of Aflatoxins in Corn and Peanut Butter, Using a Disposable Silica Gel Column, Thin Layer Chromatography, and Gas Chromatography/Mass Spectrometry
Authors: Trucksess Mary W , Brumley William C , Nesheim Stanley 
Published: February 2020

Abstract
Asimple, rapid, and solvent-efficient method for determining aflatoxins in corn and peanut butter is described. Aflatoxins B1, B2, G1, and G2 were extracted from SO g sample with 200 mL methanol-water (85 + 15). A portion of the extract was diluted with 10% NaCl solution to a final concentration of 50% methanol, and then defatted with hexane. The aflatoxins were partitioned into chloroform. The chloroform solution was evaporated, and the residue was placed on a 0.5 g disposable silica gel column. The column was washed with 3 mL each of hexane, ethyl ether, and methylene chloride. Aflatoxins were eluted with 6 mL chloroform-acetone (9 + 1). The solvent was removed by evaporation on a steam bath, and the aflatoxins were determined using thin layer chromatography (TLC) with silica gel plates and a chloroform-acetone (9 + 1) developing solvent. Overall average recovery of aflatoxin B] from corn was 82%, and the limit of determination was 2 ng/g. For mass spectrometric (MS) confirmation, aflatoxin B1, in the extract from 3 g sample (20 ng/g) was purified by TLC and applied by direct oncolumn injection at 40°C into a 6 m fused silica capillary gas chromatographic column. The column was connected directly to the ion source. After injection, the temperature was rapidly raised to 250¯C, and the purified extract was analyzed by negative ion chemical ionization MS.