bluuebunny/crossref_metadata_2025_split huggingface dataset:
Collaborative Study of a Mineral Oil Method for the Extraction of Light Filth from Ground Paprika
Authors: Thrasher Joel J , Gentry Rose 
Published: February 2020

Abstract
An official first action method for the extraction of light filth from spices, 44.A03— 44.A05, was modified for the analyses of ground paprika. The sample is extracted with isopropanol and light filth is isolated from 40% isopropanol with mineral oil. Eight collaborators analyzed 4 paprika samples, 2 by the official method and 2 by the proposed method. Average recoveries of added elytral squares were 97 and 66%, respectively, for the proposed and official methods. Recoveries of added rodent hairs were 94 and 61%, respectively. The method has been adopted as official first action for the extraction of light filth from ground paprika.
Automated Determination of Thiamine and Riboflavin in Various Foods
Authors: Pelletier Omer , Madère Rene 
Published: February 2020

Abstract
Thiamine and riboflavin were determined in various foods by automated analysis. Foods hydrolyzed before diastase digestion usually yielded more of both vitamins, except for lower thiamine values in fish and nonprocessed meats. Loss of both vitamins during the separation of insoluble matter from certain fruits was prevented by adding ethylene glycol monomethyl ether. Extraction in the presence of cysteine gave higher thiamine values in samples dehydrated with heat such as milk and potatoes. Recoveries of flavin adenine dinucleotide (FAD) and thiamine pyrophosphate (TPP) were complete with the automated methods, but recoveries of FAD were less satisfactory with AOAC method 43.039—43.042. Riboflavin values by the AOAC method agreed with those by the automated method in cereals, meats, and dairy products but were slightly higher in other foods. The automated method appears more specific because it directly measures total riboflavin, including that derived quantitatively from FAD and flavin mononucleotide (FMN), while in the AOAC method the natural forms are hydrolyzed to FMN which is measured against a riboflavin standard. Much of the interfering fluorescent compounds are separated from riboflavin in the flow-through automated system. In general, variations from day to day were quite acceptable by the automated methods but often unacceptable by the AOAC riboflavin method.
Analyses of Fat-Soluble Vitamins, XIV. Collaborative Study of the Determination of Vitamin D in Multivitamin Preparations
Authors: Mulder Frits J , De Vries Ellen J , Borsje Ben 
Published: February 2020

Abstract
The colorimetric assay for the determination of vitamin D (4000—50,000 international units (IU)/g) in multivitamin preparations has been collaboratively studied. The method is based on the same principle as the official method for the determination of vitamin D in concentrates, i.e., elimination of trans-isomers of vitamin D resins. The method includes the following steps: saponification and extraction (isolation of unsaponifiable material), phosphate-treated alumina column chromatography (elimination of tocopherols and vitamin A decomposition products), partition chromatography with polyethylene glycol 600 and Celite (separation of vitamin D fraction from vitamin A alcohol), adsorption chromatography on Florex (elimination of vitamin A decomposition products and small amounts of polyethylene glycol 600), maleic anhydride addition reaction (elimination of trans-isomers of vitamin D resins), and colorimetric determination at 2 wavelengths with and without acetic anhydride (an inhibitor for the color reaction of vitamin D and antimony trichloride). The mean result of 4 laboratories for 8 different samples, expressed as per cent of the known amount of vitamin D added, was 95.8% with a coefficient of variation of 10.5%. Considering the complexity of the method, the collaborative results were reasonable. The method has been adopted as official first action.
Chelate Extraction and Flame Atomic Absorption Spectrometric Determination of Nanogram Amounts of Manganese in Blood and Animal Tissue
Authors: Shearer Duncan A , Cloutier Richard O , Hidiroglou Michael 
Published: February 2020

Abstract
A method for the determination of manganese in blood and animal tissue has been developed involving wet digestion of the sample by perchloric and nitric acids, complexing with sodium diethyldithiocarbamate, and extracting with methyl isobutyl ketone at pH 6.7. The methyl isobutyl ketone is removed, and the residue is dissolved in 0.05N HCl in acetone-water (9+1) and is aspirated into an air-acetylene flame of an atomic absorption spectrometer. The limit of detectability is about 10 ng Mn/ml in the solution aspirated or 2 ng Mn/ml in bovine blood for a 20 ml sample.
Microbiological Assay of Thiopeptin in Broiler Rations
Authors: Takano Norio , Nomura Kimiko , Arakawa Akira 
Published: February 2020

Abstract
A microbiological assay method is described for the determination of thiopeptin in poultry feeds. Feed samples are extracted with acetone-water (9+1). Interfering substances are compensated for by extracting standard solutions from antibiotic-free feed. Microbiological activity is measured on monolayer agar plates by the paper disk diffusion method with Acholeplasma laitllaivii A. Concentrations are calculated from the responses to high and low levels of the unknown and the standard. A mean recovery of 96% was obtained from samples prepared by fortifying basal feeds in the laboratory with thiopeptin at concentrations ranging from 0.6 to 2.0 mg/kg shortly before extraction. The average recovery rate was 93% in feed samples prepared by 5 feed manufacturers with thiopeptin concentrations ranging from 0.6 to 2.5 g/ton.
Gas-Liquid Chromatographic Determination of Diflubenzuron (Dimilin) in Water as Its Trifluoroacetyl Derivative
Authors: Worobey Brian L , Webster G R Barrie 
Published: February 2020

Abstract
A new gas-liquid chromatographic (GLC) procedure has been developed for the analysis of diflubenzuron, 1-(4-chlorophenyl)-3-(2,6-difluorobenzoyl) urea, in pond water. The residues from fortified pond water were extracted with ethyl acetate, derivatized, and cleaned up on a mini Florisil column. The diflubenzuron was determined by GLC as its N,N′-di(trifluoroacetyl) derivative, using electron capture detection. A 50% full scale deflection was obtained with 0.03 ng injected. Recoveries from fortified unfiltered pond water were 65.7, 72.8, 82.0, and 90.8% at the 0.020, 0.059, 0.197, and 0.788 mg/L (ppm) levels, respectively. Recoveries from fortified filtered pond water were 94.1 and 89.3% at the 0.020 and 0.060 mg/L levels, respectively. It is postulated that diflubenzuron is immobilized by adsorption, for example, to particulate organic matter in the pond water because recovery data from unfiltered water followed the linear form of the Freundlich equation.
Automated Analytical System for Phenols Incorporated into Screening Method Suitable for Determination of 2-Methyl-4-chlorophenoxyacetic Acid and/or 2,4-Dichlorophenoxyacetic Acid Herbicide Residues in Water
Authors: Ott Daniel E , Friestad Hakon O 
Published: February 2020

Abstract
2-Methyl-4-chlorophenoxyacetic acid (MCPA) and 2,4-dichlorophenoxyacetie acid (2,4-D) are extracted from water with methylene chloride and are degraded when heated in the presence of pyridine hydrochloride to their corresponding phenols which are determined automatically with a modified distillation-colorimetric analyzer system. The method has been evaluated primarily with surface water samples collected from areas of known MCPA applications. The lower limit of detection of MCPA is about 50 µg/L water. Response for 2,4-D is almost identical to that for MCPA at equal concentrations. Comparative responses to other potential responding phenoxy acid herbicides have not been determined. MCPA results from this method for several water samples compared favorably with results from a gas chromatographic method. The scntiautontated colorimetric method can be applied to water samples of unknown history as a screening method in which case a significant, positive recorder response, suitably corrected for free phenol response as suggested herein, indicates probability of presence of one or more of the responding herbicides. The sample would then need to be examined by other, more definitive means.
Thin Layer Chromatographic Detection of Carum bulbocastanum Koch in Carum carvi Linn
Authors: Sen Asit R , Sardar Pranab K , Sengupta Pratima 
Published: February 2020

Abstract
A rapid thin layer chromatographic method has been developed to detect Carum bulbocastanum Koch in Carum carvi Linn. The volatile essential oils are developed on silica gel G plates, using benzene-petroleum ether and visualized by 2,4-dinitrophenylhydrazine spray. This procedure can also differentiate mixtures of the 2 seeds.
Analysis of Polychlorinated Biphenyls by Carbon-13 Nuclear Magnetic Resonance Spectroscopy
Authors: Levy George C , Hewitt James M 
Published: February 2020

Abstract
A technique is presented for the analysis of polychlorinated biphenyl mixtures by assigning 13C resonances to the observed peaks and matching these shifts to the shifts of known individual polychlorinated biphenyls. The technique has not proved to be as useful for heavily chlorinated mixtures.
Micro-Determination of p-Hydroxybenzoic Esters in Pharmaceuticals and Cosmetics
Authors: Weisenberg Emil , Gershon Baruch , Schoenberg Judith 
Published: February 2020

Abstract
A rapid and specific method is described for the determination of microamounts of methyl, propyl, and butyl p-hydroxybenzoic esters (parabens) in pharmaceuticals and cosmetics. The method involves the direct extraction of parabens into benzene or chloroform followed by derivatization with phosphorochloridate. The diethyl phosphate ester derivatives are cleaned up on a Florisil minicolumn and finally measured by gas-liquid chromatography on 5% OV-210 on Gas-Chrom Q. A flame photometric detector or a KCl thermionic detector may be used. The concentration response was linear up to 40 ng parabens. The reproducibility and margin of error were tested with fortified samples. This method may be applied to the estimation of other phenol derivatives.
Field Desorption Mass Spectrometry of Mycotoxins and Mycotoxin Mixtures, and Its Application as a Screening Technique for Foodstuffs
Authors: Sphon James A , Dreifuss Peter A , Schulten Hans-Rolf 
Published: February 2020

Abstract
The field desorption mass spectra of a variety of mycotoxins have been studied. These include the 4 aflatoxins B1, B2, G1; and G2, rubratoxin B, T-2 toxin, and zearalenone, as well as mixtures of these mycotoxins. The spectra of all of the mycotoxins exhibited molecular ions [M]+. Under the conditions employed, only rubratoxin B exhibited major fragmentation. The field desorption technique has been applied to the analysis of both spiked and naturally contaminated extracts of foodstuffs. The potential of the method as an analytical screening technique for the presence of mycotoxins has been evaluated.
Gas-Liquid Chromatographic Determination of m-Phenoxybenzyl cis, trans-(±)-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate in Aqueous Formulations
Authors: Simonaitis Richard A , Cail R Spencer , Zehner James M , Bry Roy E 
Published: February 2020

Abstract
A simple and rapid gas-liquid chromatographic (GLC) method was developed for the analysis of aqueous solutions of FMC 33297 (m-phenoxybenzyl cis,trans-(±)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate). The compound is extracted from aqueous solution with benzene and cleaned up by liquid chromatography. The sample extracts are analyzed by GLC with a flame ionization detector and quantitated by comparing integrator counts of extracts with those of standards. Recoveries of FMC 33297 were 90—100%. The method has good precision (the standard deviation for 4 determinations of a 0.002394% formulation was 6 × 10−6) and is sensitive to 0.00004% active ingredient by weight.
Trace Analysis of Zearalenone and/or Zearalanol in Animal Chow by High Pressure Liquid Chromatography and Gas-Liquid Chromatography
Authors: Holder Claude L , Nony Charles R , Bowman Malcolm C 
Published: February 2020

Abstract
An analytical method is described for determining residues of the estrogens zearalenone and/or zearalanol in animal chow at levels as low as 10 ppb. The chow is extracted with methanol and cleaned up by a 3-step procedure employing a Sephadex LH-20 column, liquid-liquid partitioning at pH 13 and 8.3, and a silica gel column. Residues of the 2 compounds, separated on silica gel, are assayed by using high pressure liquid chromatography with ultraviolet detection. Additional data are also included concerning p-values of the compounds in several solvent systems, Rf values from thin layer chromatography with 9 solvent systems, solubilities in 3 solvents, and a procedure for preparing their pentafluoropropionyl derivatives for analysis by electron capture gas-liquid chromatography.
Detection of Low-Level Carbadox Residues in Animal Feeds by High Pressure Liquid Chromatography
Authors: Luchtefeld Ronald G 
Published: February 2020

Abstract
The high pressure liquid chromatographic (HPLC) method is capable of detecting from 1 to 0.024 ppm methyl 3-(2-quinoxalinyl-methylene) carhazate-Nl,N4-dioxido (carbadox). Carbadox is extracted from the feed with 2% NH4OH in acetone, passed through a liquid-liquid partition, subjected to HPLC, and detected by using a 365 nm detector. No feed materials or other active drug ingredients produced false positive results.
Modified Sutter’s Arginine Dihydrolase Medium for Pseudomonas Speciation
Authors: Cary Sylvia G 
Published: February 2020

Abstract
Sutter’s arginine dihydrolase medium has been modified to obtain maximum yields of arginine dihydrolase. Bromothymol blue is the indicator for alkalinity in Sutter’s medium. By adding glucose and lowering the pH of the medium, more positive reactions were obtained in 24 hr as well as a sharper color contrast to the base medium which facilitated reading the reactions. The modified Sutter’s medium was included in the routine biochemical schema for speciation of pseudomonads isolated from cosmetic products. Of the 706 strains belonging to the 5 species isolated from cosmetic products, only one false negative reaction was obtained with a strain of Pseudomonas putida. The medium was also used for the biochemical characterization of 122 Pseudomonas sp. isolates.
An Improved Cooked Meat Medium for the Detection of Clostridium botulinum
Authors: Quagliaro Daniel A 
Published: February 2020

Abstract
A new medium composed of cooked meat and fluid thioglycolate broth was tested with 20 proteolytic and 11 saccharolytic strains of Clostridium botulinum. All of the proteolytic strains produced a black ring at the surface of the broth, presumably due to hydrogen sulfide production, while the saccharolytic strains produced white opaque rings. Since the black ring is formed rapidly and is easily seen, the new medium may be useful for the rapid identification of proteolysis in unknown isolates. Growth and toxin production were better in the new medium than in the usual cooked meat medium or in cooked meat medium plus 0.5% glucose. These results suggest that the new medium will be useful in facilitating identification of C. botulinum.
Gas-Solid Chromatographic Confirmation of Vinyl Chloride Levels in Oils and Vinegars by using Electrolytic Conductivity Detection
Authors: Page B Denis , O’Grady Ronald 
Published: February 2020

Abstract
A gas-solid chromatographic headspace method has been developed for the quantitative confirmation of vinyl chloride (VC) in oils and vinegars. The method, based on the electrolytic conductivity detector, permits quantitative confirmation of VC residues as low as 0.05 and 0.02 ppm for oil and vinegar, respectively. A number of samples were analyzed by using a previously reported flame ionization method and the proposed technique. The results by using the latter technique averaged 5% lower.
Aflatoxin and Zearalenone Occurrence in Dry-Milled Corn Products
Authors: Stoloff Leonard , Dalrymple Barbara 
Published: February 2020

Abstract
Eighty-two com dry-milling establishments in 20 States were surveyed concerning control practices for preventing the use of corn contaminated with aflatoxin or zearalenone. Prime products and by-products from each establishment were analyzed for these mycotoxins to determine whether a correlation exists between control practices and product contamination. No zearalenone was detected in any product; there was little awareness of the potential for contamination with this mycotoxin. No correlation was found between control practices and aflatoxin contamination encountered, but there was a positive correlation between aflatoxin contamination and the geographical source of the corn. Reported experimental findings in regard to the distribution of aflatoxin between prime product and by-product were generally corroborated.
Gas-Liquid Chromatographic Determination of Solvents in Commercial Nail Lacquer Preparations
Authors: Stutsman Martin J 
Published: February 2020

Abstract
A gas-liquid chromatographic (GLC) method has been developed for the determination of 5 solvents (butanol, butyl acetate, ethyl acetate, 2-propanol, and toluene) and camphor in commercial nail lacquer preparations. Resins and pigments are first precipitated from the solvents by dilution with isooctane. n-Propyl acetate is then added as an internal standard to the isooctane solution of solvents and the mixture is analyzed by temperature-programmed GLC. Analyses at 3 concentration levels (4, 20, and 40%) with 4 determinations at each level gave good recoveries.
Ultraviolet Determination of Chlordimeform in Cattle Dipping Baths and Sprays
Authors: Machin Michael V , Dingle John H P 
Published: February 2020

Abstract
A simple and reliable method has been developed for determining chlordimeform. A preliminary cleanup converts chlordimeform to its hydrochloride and removes ultraviolet-absorbing impurities. The aqueous acid phase containing chlordimeform. HCl is diluted and passed through a silica gel column. The column effluent is used as the reference solution and a portion not eluted through silica gel is used as the sample solution in the spectrophotometer. The absorbance at 240 nm is measured, and chlordimeform concentration is determined from the calibration graph. The method applied to solutions of acaricides gives good results in the range of 0.02–0.06% w/v chlordimeform; higher concentrations may be determined by appropriate dilutions.
Gas Chromatographic Determination of Residual Methylene Chloride and Trichloroethylene in Decaffeinated Instant and Ground Coffee with Electrolytic Conductivity and Electron Capture Detection
Authors: Page B Denis , Charbonneau Claudette F 
Published: February 2020

Abstract
A method is described for the quantitative determination of residual methylene chloride (MC) and trichloroethylene (TCE) in decaffeinated instant and ground roasted coffees. The residual solvents were isolated by a closed system vacuum distillation technique with toluene as a carrier solvent, chromatographed on Chromosorb 102, detected by both electron capture and electrolytic conductivity detectors, and quantitated by comparison with an internal standard. Average recoveries of MC from instant and ground coffees spiked at 1, 10, and 25 ppm were 100.0 (88-113), 93.2 (92-95), and 97.7% (94-102%); and for TCE, 97.2 (92-101), 96.2 (95-99), and 96.5% (92-100%), respectively. The results from both detectors are compared. At lower attenuations, levels less than 1 ppm can be readily measured. The procedure developed was applied to domestic and imported coffee samples.
Collaborative Study of Gas-Liquid Chromatographic Method for Determining Fluometuron
Authors: Hofberg Arthur H , Heinrichs Lee C , Barringer V Michael , Tin Maung , Gentry Gene A 
Published: February 2020

Abstract
A gas-liquid chromatographic (GLC) method for determining fluometuron in a wettable powder formulation containing about 80% active ingredient was collaboratively studied using a matched pair scheme. The samples were dissolved in chloroform containing diethyl phthalate as an internal standard, derivatized with trifluoroacetic anhydride, and chromatographed on OV-3, using a flame ionization detector. Analyses of the 2 samples by 14 collaborators, using peak height measurements, showed the following results: 0.99% overall coefficient of variation, 1.08% coefficient of variation for the random error, and no evidence of systematic error. The validity of these results was verified by a concurrent collaborative effort using high pressure liquid chromatography. Analyses of the 2 samples by 8 collaborators, using peak height measurements, showed a 1.17 standard deviation of the total for liquid chromatography vs. 0.76 standard deviation of the total for GLC. The averages for Sample A and Sample B by liquid chromatography showed a relative difference of 0.19 and 0.00%, respectively, when compared with the results by the GLC method. The GLC method has been adopted as official first action.
Comparison of Semiautomated and Manual Methods for the Determination of Thiamine in Baby Cereals and Infant and Dietary Formulas
Authors: Ribbron Wallace M , Stevenson Kenneth E , Kirk James R 
Published: February 2020

Abstract
Using a semiautomated method, the mean thiamine content of specific products ranged from 88 to 101% and 83 to 93% for baby cereals and infant and dietary formulas, respectively, of those obtained with the AOAC manual method. The best results were obtained when data for the semiautomated method were calculated from a standard curve obtained by using thiamine solutions which had been digested and hydrolyzed along with the samples.
Aflatoxins in Egyptian Foodstuffs
Authors: Girgis Amir N , El-Shbrif Safinaz , Rofael Nazmy , Nesheim Stanley 
Published: February 2020

Abstract
Six samples each of wheat, corn, lentils, beans, fenugreek, peanuts, and cottonseed cake from various areas of Egypt were analyzed for aflatoxins both at the time of collection and after 12 months’ storage. Aflatoxin was found at low levels (3 to 12 ppb total aflatoxins in 14 of 42 samples, as follows: 1 sample each of corn, lentils, and beans; 2 peanut samples; 3 fenugreek samples ; and 6 cottonseed cake samples. None of the samples contained aflatoxins above 11.7 ppb.
Aflatoxin in Tunisian Aleppo Pine Nuts
Authors: Boutrif Ezzeddine , Jemmali Mongi , Pohland Albert E , Campbell Alfred D 
Published: February 2020

Abstract
Twenty-six of 50 Aleppo pine nut samples collected throughout Tunisia showed relatively high levels of contamination by aflatoxin. Some samples contained as much as 2000 ppb aflatoxin B1, and very few contained less than 100 ppb. Total aflatoxins as high as 7550 ppb were found. A traditional pudding, widely consumed in Tunisia, which was prepared from contaminated nuts still contained more than 80% of the aflatoxin originally present in the nuts.
Survey of 1975 Wheat and Soybeans for Aflatoxin, Zearalenone, and Ochratoxin
Authors: Shotwell Odette L , Goulden Marion L , Bennett Glenn A , Plattner Ronald D , Hesseltine Clifford W 
Published: February 2020

Abstract
Wheat samples (102 lots) were collected from Virginia, North Carolina, southeastern Missouri, southern Illinois, and Kentucky. Soybean samples (180 lots) were collected from Virginia, Illinois, Iowa, Minnesota, Nebraska, Alabama, Arkansas, and Texas. Samples of both commodities were analyzed for zearalenone, aflatoxin, and ochratoxin by the Eppley method. None of the 3 mycotoxins was detected in soybeans. Aflatoxins and ochratoxin A were not detected in wheat, but zearalenone was detected in 19 of 42 samples collected in Virginia. Half of the Virginia samples were collected because they were mold-damaged. Zearalenone levels ranged from 0.36 to 11.05 ppm; the identity of the zearalenone was confirmed by gas-liquid chromatography and mass spectroscopy. Gibberella zea infection (6–60%) was detected in all of the zearalenone-positive samples; 6–60% of the kernels in the samples tested contained G. zea.