bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid Spectrophotometric Method for Determination of 2-Aminobutane in Postharvest Dips
Authors: Baker Harvey J 
Published: February 2020

Abstract
A rapid method is described for measuring 2-aminobutane in postharvest dip fluids. Samples of the dip fluid are diluted to bring the 2-aminobutane content in the range 500—5000 μg and reacted with carbon disulfide and cupric ion to form a chloroform-extractable complex measured spectrophotometrically at 430 nm. The accuracy and reproducibility of the method are comparable with the more lengthy modified product and residue methods.
High Pressure Liquid Chromatographic Determination of Aflatoxins in Peanut Products
Authors: Pons Walter A , Franz Anthony O 
Published: February 2020

Abstract
A precise and sensitive high pressure liquid chromatographic method is proposed for determining aflatoxins B1, B2, G1, and G2 in all types of peanut products. The method is based on acidified aqueous methanol extraction, partition of aflatoxins into dichloromethane, and purification of the extract on a 2 g silica gel column. Aflatoxins in the purified extract are completely resolved on a microparticulate (10 μm) porous silica gel column in approximately 10 min with a water-saturated chloroform-cyclohexane-acetonitrile solvent. The preferred detection system, B1 and B2 by ultraviolet absorbance at 360— 365 nm and G1 and G2 by fluorescence, allows accurate and sensitive detection of all 4 aflatoxins at levels as low as 0.3—1.0 μg/kg. Repetitive assay of 3 samples of naturally contaminated peanut butters containing total aflatoxins (B1 + B2 + G1 + G2) at levels of 5, 10, and 15 μg/kg gave within-laboratory coefficients of variation of 11, 5, and 5%, respectively.
Headspace Sampling and Gas-Solid Chromatographic Determination and Confirmation of ≥ 1 ppb Vinyl Chloride Residues in Polyvinyl Chloride Food Packaging
Authors: Dennison J Lawrence , Breder Charles V , Mcneal Timothy , Snyder Roger C , Roach John A , Sphon James A 
Published: February 2020

Abstract
The determination and confirmation of residual vinyl chloride (VC) in polyvinyl chloride (PVC) food packaging materials are described. PVC packaging materials are dissolved in dimethylacetamide (DMAC). VC is sparged from solution with helium gas and collected in sealed vials of ethanol. VC is detected and quantitated by using a headspace sampling technique and standard gas-solid chromatography (GSC) with flame ionization detection. GSC peak heights of about 5% full scale deflection are obtained for samples of PVC containing 1 ppb VC. Polymer samples taken from tubing, blood bags, food packaging films, bottles, and unprocessed resin were analyzed. Residual VC levels ranged from 0.3 to 913 ppb. VC was confirmed by GSC-mass spectrometry, using selected ion recording of m/z 62 and 64 in conjunction with full mass scans to identify components eluting near VC.
Gas-Liquid Chromatography and Flame Photometric Detection of Phosphine in Wheat
Authors: Nowicki Thomas W 
Published: February 2020

Abstract
A screening method using gas-liquid chromatography with flame photometric detection has been developed for determining phosphine in wheat. Phosphine is measured as the sum of physically bound intact phosphine and that derived from residual aluminum phosphide. Wheat is extracted in a closed, partially evacuated glass system by refluxing with 10% sulfuric acid. Liberated gases are swept into a gas-collection flask fitted with rubber septa to permit gas sampling. Aliquots of collected gas are injected into a gas chromatograph. Phosphine is quantitated by peak area as determined by an electronic integrator. Recoveries varied with concentration: 67% was recovered at 0.10 ppm and 98% was recovered at 19 ppm. For concentrations less than 1.5 ppm, the coefficient of variation was 9.95%. Using flame photometric detection, phosphine concentrations as low as 0.04 ppm were easily determined in wheat.
Microcolorimetric Method for Determining Boron in Fertiliz
Authors: Thorpe Virginia A 
Published: February 2020

Abstract
A modification and evaluation of an unpublished azomethine H colorimetric method for determining boron in fertilizer are described By changing formulations of the color reagent and buffer-masking solution, interferences were eliminated and color development reached a maximum in 1 hr and remained stable for an additional hour. The method was simplified by combining the color reagent and buffer-masking solution; matrix and acid effects were controlled by adjusting sample and acid background in the solution, thus eliminating the need for standard addition techniques. Samples with boron contents from 0.03 to 3.0% were analyzed with the proposed method; the expected values were obtained with coefficients of variation of 3.19 and 1.27%, respectively, for the low and high levels of boron.
High Pressure Liquid and Thin Layer Chromatography of Synthetic Acid Fast Dyes in Alcoholic Products
Authors: Martin Glenn E , Tenenbaum Milton , Alfonso Felipe , Dyer Randolph H 
Published: February 2020

Abstract
High pressure liquid chromatography (HPLC) was used to resolve FD&C Blue No. 1 (Brilliant Blue), FD&C Blue No. 2 (Indigotine), Amaranth (formerly certified as FD&C Red No. 2 ) , FD&C Red No. 3 (Erythrosine), FD&C Red No. 4, FD&C Red No. 40, FD&C Yellow No. 5 (Tartrazine), FD&C Yellow No. 6 (Sunset Yellow FCF), and FD&C Green No. 3 (Fast Green FCF). These synthetic acid fast dyes as found in wine and flavor samples were extracted with wool yarn and analyzed by HPLC and thin layer chromatography. The 2 methods are compared for sensitivity and resolution. The HPLC procedure is a quicker way to screen a larger number of samples for artificial colors with better resolution than that obtained by thin layer chromatography. HPLC can separate FD&C Red No. 40 from FD&C Red No. 4 and this could not be achieved by using the described TLC solvent system. The FD&C dyes most commonly found in flavors and distilled spirits were FD&C Red No. 40, FD&C Yellow No. 5, and FD&C Yellow No. 6.
Fluorometric Determination of Metaraminol Bitartrate Injection
Authors: Weber John D 
Published: February 2020

Abstract
A fluorescence assay for metaraminol bitartrate injection has been developed which uses o-phthalaldehyde as a fluorogenic reagent, and does not require prior isolation of metaraminol. It is 50 times more sensitive than the USP assay. Six analyses of 2 vials of the same lot of metaraminol bitartrate injection gave 96.0± 0.4% of label declaration.
Use of the High-Speed Over-Head Mixer in Howard Mold Count Preparations
Authors: Cichowicz Stanley M 
Published: February 2020

Abstract
High-speed blenders are used in the preparation step for mold counting of ground capsicums, onion powder, garlic powder, and tomato powder. Waring-type blenders have several disadvantages: (1) accurate rpm measurement cannot be made under load conditions; (2) an external variable transformer must be used to regulate the speed; (3) different models can have varying top speeds. The over-head Sorvall-type mixer overcomes these disadvantages. It has a built-in speed control and can be calibrated under load conditions by direct access through the top of the motor. Test results show that there is no difference between mold counts of samples prepared by the 2 types of blenders. The high-speed over-head mixer has been adopted as an alternative to the high-speed blender now described in the official method.
Comparative Accuracy of Five Biochemical Systems for Identifying Salmonella and Related Foodborne Bacteria: Collaborative Study
Authors: Poelma Paul L , Romero Aida , Andrews Wallace H 
Published: February 2020

Abstract
The comparative accuracy of 4 biochemical diagnostic kits (API, Enterotube, Minitek, and Pathotec) and the conventional (AOAC) tube system for identifying primarily Salmonella and other enteric isolates was collaboratively studied. Each of 11 participating analysts received 40 foodborne isolates (25 Salmonella and 15 non-Salmonella cultures), representing a total of 440 cultures examined by each identification system. In decreasing order of accuracy, the overall number of correctly identified cultures with each of the systems was as follows: AOAC, 423 (96.1%), Minitek, 403 (91.6%), Enterotube, 395 (89.8%), API, 394 (89.5%), and Pathotec, 373 (84.8%). A cost analysis showed that all 4 diagnostic kit systems were less expensive than the conventional AOAC tube system for a single culture identification. Three of the diagnostic kits have been adopted as official first action as alternatives to the AOAC biochemical tube system for presumptive generic identification of foodborne Salmonella and for screening and eliminating non-Salmonella isolates. Routine incorporation of any one of the 3 diagnostic kits, however, should be preceded by the demonstration in the analyst's own laboratory of adequate correlation between the kit and the AOAC system.
Modified Method for Electron Capture Gas-Liquid Chromatographic Determination of Hexestrol Residues in Bovine Tissues
Authors: Tobioka Hisaya , Kawashima Ryoji 
Published: February 2020

Abstract
A gas-liquid chromatographic (GLC) method with electron capture detection was developed for determining hexestrol residues based on a GLC method for diethylstilbestrol residues. The extraction and purification procedures were based on a published procedure. Pentafluoropropionic (PFP) and heptafluorobutyric (HFB) anhydrides and other halogenated compounds were compared as acylation reagents. PFP anhydride was selected because it provided reproducible GLC responses. Of the 3 column packing materials tested, OV-17, OV-210, and QF-1, OV-17 was the most stable under the GLC conditions used. A pH 10.5—10.6 in the purification step gave higher recoveries than pH 10.3 or pH 10.8 and was selected for use. The method is suitable for determining residues of 0.5 ppb. The limit of sensitivity ranges from 0.1 to 0.2 ppb.
Fluorometric Determination of Histamine in Cheese
Authors: Chambers Theodore L , Staruszkiewicz Walter F 
Published: February 2020

Abstract
Thirty-one samples of cheese obtained from retail outlets were analyzed for histamine, using an official AOAC fluorometric method. The types of cheese analyzed and the ranges of histamine found were: colby, 0.3—2.8; camembert, 0 . 4 - 4 . 2 ; cheddar, 1.2-5.8; gouda, 1.3-2.4; provolone, 2.0-23.5; roquefort, 1.0-16.8; mozzarella 1.6-5.0; and Swiss, 0.4—250 mg histamine/ 100 g. Ten of the 12 samples of swiss cheese contained &lt; 1 6 mg histamine/100 g. The remaining 2 samples which contained 116 and 250 mg histamine/lOO g were judged organoleptically to be of poor quality. An investigation of one processing facility showed that the production of histamine in swiss cheese may have been a result of a hydrogen peroxide/ low temperature treatment of the milk supply. Recovery of histamine added to methanol extracts of cheese ranged from 93 to 105%. Histamine content was confirmed by high pressure liquid chromatographic analysis of the methanol extracts.
Determination of Streptomycin Residues in Eggs and Stability of Residues After Cooking
Authors: Inglis Jean M , Katz Stanley E 
Published: February 2020

Abstract
An assay procedure for streptomycin was developed, using a surfactant-pH 8 buffer extraction, heating at 85°C to eliminate inhibition from lysozyme activity, and centrifuging to remove physical- barriers to diffusion. Recoveries of streptomycin from supplemented eggs averaged 42% over the range of 0.33—2.05 jug streptomycin/g egg. Eggs were supplemented at 3.0, 30.0, and 300 /tg streptomycin/g and subjected to various cooking procedures: frying, poaching, scrambling, and hard boiling. There was little or no loss of activity as a result of the various cooking procedures with the exception of one of the hard boiled varieties where there was a 40% loss only at the 3.0 /ig/g supplementation. Streptomycin residues were quite stable to normal egg preparation procedures.
Extraction of Benzene Hexachloride Isomers from Water Samples, Using a Macroreticular Resin
Authors: Yamato Yasuhiro , Suzuki Manabu , Watanabe Tadao 
Published: February 2020

Abstract
Four BHC isomers added to 3 L BHC-free distilled water at levels of 1.0, 0.1, and 0.01 ppb were quantitatively recovered (&gt;94%), using an amberlite XAD-2 resin. Cas-liquid chromatography with electron capture detection and a column packed with 2 % Apiezon L on 100—120 mesh Gas-Chrom Q was used as a determinative step. This method was also used to detect BHC residues in tap water and river surface waters in the Kitakyushu District, Japan. The 4 BHC isomers were detected at levels below parts per trillion in almost all the samples analyzed: α-BHC &gt; β-BHC &gt; γ-BHC &gt; δ-BHC. The maximum residue level of total BHC was 0.604 ppb and the minimum was 0.007 ppb. The minimum detectability for total BHC in a 3 L water sample was 0.001 ppb.
Pentafluorobenzyl Ester Derivatives of Nine Chlorophenoxy Acid Herbicides: Spectroscopic Properties and Utility for Identification Purposes
Authors: De Beer Jacques O , Van Peteghem Carlos H , Heyndrickx Aubin M 
Published: February 2020

Abstract
The pentafluorobenzyl esters of 9 chlorophenoxy acid herbicides were synthesized by the reaction of the acids with pentafluorobenzylbromide in alkaline acetone solution. Ultraviolet (UV), infrared (IR), proton magnetic resonance (PMR), and mass spectra (MS) were recorded. IR and mass spectra are shown and UV, PMR, and MS data are tabulated and discussed. A technique for extraction of the chlorophenoxy alkyl acid herbicides, followed by conversion to the corresponding pentafluorobenzyl esters, was developed for human urine samples. Applications in different concentration ranges (ppm, ppb) by different spectroscopic techniques (MS, IR) are demonstrated.
Drug Residues in Animal Tissues and Their Regulatory Significance—The Canadian Point of View
Authors: Campbell David J 
Published: February 2020

Abstract
Today it is almost impossible to produce food of animal origin which is free from traces of drugs or chemicals. In Canada the problem of drug residues is controlled by a method of assessment of human safety which involves many factors. The toxicity of the drug in laboratory animals or, if possible, in man, is established and a no-effect dose is then estimated. These studies require oral administration of the drug and include acute, subacute, and teratogenicity studies. Depending on these results, chronic reproductive or carcinogenicity studies may be required before a no-effect dose can be estimated. Residue studies must encompass data on metabolism, pharmacokinetics, and depletion studies in edible tissues and for products such as milk and eggs. For veterinary drug residues, we must consider the target food animal with its particular metabolism, tissue disposition, and excretion patterns. The analytical method for residue detection must be acceptable and its sensitivity limits suitable for the drug and its major metabolites.
Trends in the European Communities Toward Developing Analytical Methods for Regulating Animal Drugs and Feed Additives
Authors: Somogyi Arpad 
Published: February 2020

Abstract
The heterogeneity of the legal basis in the 9 member states of the European Communities (EC) regarding the tolerance of drug residues in edible animal products precluded, until now, the establishment of common principles governing the relationship between analytical requirements and the approval of animal drugs and feed additives. While feed additives are regulated on the EC level (Directive on Additives in Feedingstuffs of 1970), no binding and comprehensive measures are currently in force regarding animal drugs. A draft proposal, presently under review by the member states, covers the regulatory aspects of approval, use, and control of veterinary medicinal substances. Furthermore, it describes in detail the analytical, pharmacological, toxicological, and clinical requirements and standards a new drug must meet before application for approval within the EC can be considered. According to this document, the first of its kind in the EC, sufficiently sensitive analytical methods must be submitted to assure that, under conditions prevailing in a routine laboratory, drug residue levels which are not considered safe will be detected. A brief outline of current measures and draft proposals of future regulations is given from the viewpoint of analytical methods for residues of animal drugs and feed additives.
Antibiotic Residues: Regulations, Tolerances, and Detection in the European Economic Community
Authors: Van Schothorst Mike , Van Leusden Frans M , Nouws Jac F M 
Published: February 2020

Abstract
The use of antimicrobial agents for growth promotion and therapy in the European Economic Community and the resulting public health problems are discussed. Methods for detection of residues based on microbiological criteria for acceptance are presented and evaluated.
Method for Antibiotic Determination in Animal Tissue, As Applied to Lasalocid
Authors: Donald Alexander Mac 
Published: February 2020

Abstract
The development of a tissue residue method for an antibiotic is dependent on the history of the overall problem; the current requirements that must be met for regulatory approval; the chemistry of the compound; its physical/chemical parameters; and its microbiological spectrum for the best possible fit of all of these to ensure a procedure that will work reliably in the originator's laboratory and to the same degree of effectiveness in anyone's laboratory. A note is made of those factors that must be included as controls on the procedure and those experiments that must be included to differentiate matrix from method influences.
Detection, Identification, and Quantitation of Organic Compounds with Bioanalytical Systems Based on Mass Spectrometry
Authors: Horning Evan C , Carroll David I , Dzidic Ismet , Stillwell Richard N , Thenot Jean-Paul 
Published: February 2020

Abstract
Bioanalytical systems which include a gas chromatograph, a mass spectrometer, and a computer provide the most effective analytical methods for organic compounds other than macromolecules. The use of computer and microprocessor/computer instrumental combinations is increasing. Electron impact mass spectrometry is used for identification purposes; chemical ionization is best for quantitative work. Current studies indicate that negative ion mass spectrometry with non-filament sources will be useful in analyses for toxic agents (pesticides, fungicides, herbicides). Future analytical systems will have both positive and negative ion mass analyzer capabilities. Sample preparation methods depend on the type of analysis. Liquid chromatography is useful when the concentration is low. Open tubular glass capillary columns are coming into wider use, both in gas chromatography alone and in combined systems. The limits of detection are now in the subpicogram range, but the determining factor is usually the nature of the compounds under analysis and the extent of adsorption.
Endogenous Estradiol-17/β in Bovine Tissues
Authors: Henricks Donald M , Torrence Allan K 
Published: February 2020

Abstract
The development of an assay for the estrogen estradiol-17β in bovine muscle, kidney, liver, and uterine endometrium is described in this report. The tissue was homogenized, extracted, partitioned, and subjected to routine radioimmunoassay. Chromatography was not used. The first part of the report presents data on the accuracy, reproducibility, and sensitivity of the assay. The concentration of estradiol-17β in the tissues compared with muscle was ranked as follows: uterine endometrium (10-fold higher), liver (3-fold), and kidney (3-fold). The estrogen concentration was not significantly different in the muscle between heifers, but was significantly greater (P &lt; 0.05) in the liver and kidney of heifers and steers. In heifers pre- and post-estrous phase endometrium (a target tissue of E2β) contained significantly greater concentrations of estradiol-17β than did luteal phase endometrium (P &lt; 0.05), but mean levels in the edible tissues were not significantly different (P &gt; 0.05) between these 2 of the 4 stages of the estrous cycle.
Atomic Absorption Spectrometric Determination of Arsenic and Selenium in Offal and Fish by Hydride Generation
Authors: Flanjak Johann 
Published: February 2020

Abstract
A method for determining As and Se in beef offal and fish was developed. The sample was digested by heating with a mixture of nitric, perchloric, and sulfuric acids. No pre-reduction of As and Se was necessary. Using a simplified generator, the metal hydrides were evolved by reduction with sodium borohydride pellets from sulfuric and hydrochloric acid media. The hydrides were swept by a flow of nitrogen into a nitrogen-hydrogen-entrained air flame. Absolute detection limit of the method was about 6 ng for As and 4 ng for Se, and absolute sensitivity for both metals was estimated to be 5 ng. Effects of the presence of several cations and anions in the matrix were investigated and some were found to have a suppressive effect on the atomic absorption signal. The analytical results obtained for samples of NBS No. 1571 Orchard Leaves and NBS No. 1577 Bovine Liver agreed well with certified values.
Mass Fragmentographic Determination of Pentachlorophenol in Rainbow Trout
Authors: Wu Anthony , Lech John J , Glickman Andrew , Lynn Pearson M 
Published: February 2020

Abstract
Pentachlorophenol (PCP) is extracted from selected tissues of rainbow trout and converted to pentachloroanisole (PCA) by means of alkylation in the presence of potassium carbonate as a condensing agent. Pentachlorophenetole (PPT) is used as an internal standard. The electron impact mass fragmentography is carried out by monitoring m/e 280 (PCA), 294 (PPT), and 237. A plot of peak height vs. concentration is linear from 0.03 to 4.0 ng. Accuracy and precision of the method is ± 2% (N = 36). The results are accurate enough to warrant the use of this method for determining PCP in fish, as well as for monitoring PCP from various environmental sources. In addition, this technique provides a simple and rapid method by which a mixture of PCA and PCP can be determined simultaneously.
Enumeration of Coliforms and Salmonella in Food Prepared by Blending and Stomaching
Authors: Andrews Wallace H , Wilson Clyde R , Poelma Paul L , Romero Aida , Mcclure Foster D , Gentile Dorothy E 
Published: February 2020

Abstract
The efficiencies of the Waring blender, the Stomacher 400, and the Stomacher 3500 were compared for preparing food samples for enumerating coliforms and Salmonella. Comparative most probable number (MPN) determinations were performed on 289 samples, representing 12 categories of nonfatty foods and 2 categories of fatty foods. Total coliforms were enumerated in 9 categories of nonfatty foods, and the geometric means of MPNs in samples prepared by the Stomacher 400 and the Stomacher 3500 were not statistically different from those means of MPNs of samples prepared by the blender in 100 and 89% of the categories, respectively. In the 3 categories of nonfatty foods in which fecal coliforms were enumerated, geometric means of the MPNs of samples prepared by the Stomacher 400 and the Stomacher 3500 were not statistically different from those means of MPNs of samples prepared by the blender in 3 and 2 of the food categories, respectively. Of the 3 categories of nonfatty foods in which Salmonella was enumerated, geometric means of the MPNs of samples prepared by the Stomacher 400 and the Stomacher 3500 were not statistically different from those means of MPNs of samples prepared by the blender in 3 and 2 of the categories, respectively. Adding Tween 80 to 2 categories of fatty foods at final concentrations of 0.5, 1.0, and 2.0% did not result in a consistent increase in coliform MPNs obtained after stomaching with either model.