bluuebunny/crossref_metadata_2025_split huggingface dataset:
CIPAC Collaborative Study of the Heat-Stability of Diazinon Formulations, Using Both CIPAC and AOAC Analytical Methods
Authors: Eberle Dieter O , Suter Rolf , Nowak Klaus , Bosshardt Hans P 
Published: February 2020

Abstract
Diazinon (O,O-diethyl O-(2-isopropyl-6-methyl-4-pyrimidinyl) phosphorothioate) and 3 different Diazinon formulations were analyzed both by the official CIPAC titrimetric method and by the AOAC official first action gas chromatographic method. In addition, all samples were subjected to the CIPAC accelerated storage test by heating (2 weeks at 54°C) and analyzed by the 2 methods before and after storage. Eight collaborators from European countries and the United States took part in the study. Analytical results were reproducible within and between laboratories by both methods. As demonstrated by an analysis of variance, the 2 procedures yielded identical results. Therefore, both the CIPAC and the AOAC methods may be considered as equivalent with good accuracy and reproducibility. After storage at 54°C for 14 days only one Diazinon dust formulation revealed a significant decrease in Diazinon content as shown by a t-test.
Gas-Liquid Chromatographic Determination of Diethylstilbestrol Monomethyl Ether in Diethylstilbestrol
Authors: Gainer Frank E , Chiasson William J 
Published: February 2020

Abstract
A gas chromatographic method is described for the determination of the monomethyl ether of diethylstilbestrol (MME) in diethylstilbestrol (DES). A 1 g sample of DES is dissolved in an aqueous solution of 0.5N sodium hydroxide and extracted with a chloroform solution containing benefin, the internal standard. The chloroform solution is back-extracted with sodium hydroxide, and an aliquot is chromatographed after silylation. The MME peaks (cis and trans') are measured relative to the internal standard peak. The method was tested for accuracy within the 120—2000 ppm range, and a linear plot of detector response vs. concentration was obtained. The method is also suitable for the determination of diethylstilbestrol dimethyl ether (DME) if present with MME in a DES sample.
Alkaline Distillation of Ammoniacal and Nitrate Nitrogen with Raney Catalyst Powder
Authors: Johnson Frank J , Miller Danish L 
Published: February 2020

Abstract
Raney catalyst powder was substituted successfully for Devarda alloy in the direct distillation of ammoniacal and nitrate nitrogen, and the catalyst powder was slightly more efficient than the alloy. Nitrate-containing fertilizer materials and some synthetic mixed fertilizers were analyzed by direct distillation with Raney catalyst powder as well as by accepted methods. The proposed method is precise and accurate, and is applicable to fertilizers containing ammoniacal and nitrate nitrogen and no other forms of nitrogen.
Liquid Chromatographic System for Separating Opium Alkaloids
Authors: Beasley Thomas H , Smith David W , Ziegler Howard W , Charles Richard L 
Published: February 2020

Abstract
A high-pressure liquid chromatographic procedure has been developed for the separation of 6 major alkaloids in gum or powdered opium. The alkaloids are absorbed from an aqueous dimethylsulfoxide solution onto a strong cation exchange resin and eluted with methanolammonia; the solvent is removed by reduced pressure evaporation. The alkaloids from the residue are then dissolved in chloroform-methanol (3+1). The sample solution, plus brucine alkaloid as an internal standard, is placed on a Corasil Type II column (microbore) and eluted with hexane that is gradient programmed with a solution of chloroform-methanol-diethylamine (100+300+1). The absorbance of the eluate is continuously monitored in a flow-through ultraviolet photometer.
Collaborative Study of the α-Toxin Method for Estimating Population Levels of Clostridium perfringens in Food
Authors: Harmon Stanley M , Kautter Donald A 
Published: February 2020

Abstract
A microbiological method for estimating population levels of Clostridium perfringens in food, based on the presence of α-toxin, was studied collaboratively in 15 laboratories. The collaborators extracted α-toxin from identical samples of roast beef and quantitatively determined it in hemolysin indicator plates. The titer of a-toxin found was utilized to estimate the population level of C. perfringens in the roast beef by correlating the titer of α-toxin present in the beef with experimental data on the relationship of viable counts and α-toxin production supplied to the collaborators. Forty-five of 52 samples examined were found to contain α-toxin at a dilution of 1+63 to 1+127 as measured in hemolysin indicator plates. The remainder had α-toxin titers one 2-fold dilution higher or lower. The estimated population levels obtained by the various laboratories ranged from 7.3 α 107 to 17.8 α 107/g. The standard deviation among replicate determinations within collaborators was 3.5 × 107/g. These results indicate that the precision of the α-toxin method makes it useful for estimating the maximum population of C. perfringens in a suspect outbreak food.
Automated Analyses of Sugar, Starch, and Amylose in Potatoes by Measuring Sugar-Dinitrosalicylate and Amylose-Iodine Color Reactions
Authors: Mccready Rolland M , Ducay Eufemio D , Gauger Mona A 
Published: February 2020

Abstract
Sugar-containing potato extracts were analyzed for sugars before and after invertase hydrolysis using Sumner and Sisler’s dinitrosalicylate method, modified and automated. Amylose and total starch were determined on sugar-free potato flour by automated methods, amylose was analyzed by the iodine color reaction, and starch as glucose was determined after hydrolysis with trifluoroacetic acid and reaction with dinitrosalicylate. Results were sufficiently reliable and satisfactory for surveying white potato samples for carbohydrates.
Ultraviolet Spectroscopic Determination of Dimetridazole in Feeds
Authors: Stone Loyal R , Hobson Dale L 
Published: February 2020

Abstract
A simple and rapid procedure for the determination of dimetridazole (l,2-dimethyl-5-nitroimidazole) in feeds is described, using only liquid-liquid extractions before ultraviolet (UV) measurement. The drug is more effectively separated from interfering substances by this method than by the 2 alumina chromatographic steps required in the official first action AOAC method. Dimetridazole is extracted from feed with chloroform and trisodium phosphate solution and transferred from chloroform into hydrochloric acid; sodium hydroxide is added to the solution and the drug is transferred into benzene for UV measurement. Ipronidazole and zoalene interfere. The presence of bentonite decreases recovery. The interference from natural feed ingredients is negligible. An average coefficient of variation of 1.9% and an average recovery of 98% were found on repetitive assays of 3 feeds of known dimetridazole content.
Organic Solvent Extraction of Lead and Cadmium from Aqueous Solutions for Atomic Absorption Spectrophotometric Measurement
Authors: Childs Ernest A , Gaffke John N 
Published: February 2020

Abstract
The efficiency of solvent extraction of lead and cadmium for atomic absorption spectrophotometry was investigated. Quantitative extraction from an aqueous solution into methyl isobutyl ketone was possible, using sodium diethyl dithiocarbamate in the pH range of 5.5—8.5 for Cd and 5.5—7.5 for Pb. A 4-fold concentration from aqueous to organic solvent allowed accurate measurement (error &lt;± 10%) of concentrations &lt;0.02 μg Pb/ml and &lt;0.05 μg Cd/ ml. Detection limits of 0.01 μg Pb/ml and 0.0005 fig Cd/ml were established.
Collaborative Study of a Fluorometric Method for Determining Selenium in Foods
Authors: Ihnat Milan 
Published: February 2020

Abstract
A fluorometric method for the determination of selenium in foods reported previously was studied collaboratively. Nineteen laboratories reported analytical results on 10 samples representative of vegetables, cereal, dairy products, meat, and fish, and containing naturally occurring selenium. For the 5 pairs of samples, the coefficients of variation based on precision standard deviation were 2 5 . 9% at 16 ng selenium, 15.8% at 98 ng, 8.5% at 233 ng, 6.1% at 379 ng, and 4.1 % at 427 ng. The corresponding coefficients of variation computed from overall standard deviations were 65.3, 17.5, 8.9, 8.1, and 5.6%. Systematic error was significant for 2 pairs (F-test, p = 0.01), but not for the remaining 3 (p = 0.05). The ratio of the systematic error standard deviation to the precision standard deviation varied from 0.21 to 1.64. Analyses of 2 NBS standard reference materials, orchard leaves (75 ng selenium) and bovine liver (208 ng selenium), yielded results higher by 16 and 10%, respectively. The precision and accuracy of the collaborative procedure were deemed acceptable and the method has been adopted as official first action.
Adsorption Chromatographic Separation of Chlorinated Hydrocarbons from Lipids
Authors: Claeys Robert R , Inman Roderick D 
Published: February 2020

Abstract
Florisil, alumina, and silicic acid were compared for the column chromatographic separation of lipids from chlorinated hydrocarbons. Alumina had the largest capacity per unit volume to retain lipids and oils (0.7 g beef lipid/ 25 g alumina) while eluting dieldrin. Florisil had a larger capacity than silicic acid. Deactivation and elution with a nonpolar solvent gave superior separation over previously used polar solvent elution from activated adsorbents. The effects of temperature, water, and lipid load on the elution of dieldrin were studied. A yellow dye, p-methoxyazobenzene, was found to have a slightly larger elution volume than dieldrin, and is useful as a visible reference material for the elution of chlorinated hydrocarbons.
Identification of the Photoalteration Products Formed from Parathion by Ultraviolet Light
Authors: Joiner Ronald L , Baetcke Karl P 
Published: February 2020

Abstract
A comparison of the effects of various time periods of ultraviolet light on the formation of rearrangement products of parathion is presented. Twelve products were separated and identified by thin layer chromatography in 4 systems, and were confirmed by infrared spectroscopy, when possible. The effect of 2 solvents, methanol and acetone, on the formation and percentage composition of photoalteration products of parathion from high-intensity ultraviolet light is also discussed. Retention times are given for each component from gas chromatography by electron capture and flame photometric detection.
Applications of Nuclear Magnetic Resonance Spectroscopy to Certifiable Food Colors
Authors: Marmion Daniel M 
Published: February 2020

Abstract
Nuclear magnetic resonance spectroscopy (NMR) has been evaluated as a tool for the study of certifiable food colors and found useful as a means of identifying individual colorants, differentiating between single colors and mixtures, identifying and semiquantitating the colorants in secondary mixtures, establishing the presence of excipients such as sucrose, and detecting the adulteration of a color additive with forbidden colorants. NMR also shows promise as a method to examine the purity of food colors and to study process conditions.
Extraction and Analysis of Carotenoids in Fresh Plant Materials
Authors: Quackenbush Forrest W 
Published: February 2020

Abstract
Efforts were made to develop an improved method of analysis for the carotenoids in fresh plant material. The present official final action method (39.014—39.017) does not include analysis for xanthophylls. Use of ethanol as extractant compared favorably with the use of acetonehexane mixtures specified in the present method (39.015). Direct extraction of the residue after evaporation of an aliquot of the ethanol extract avoided xanthophyll losses that may be encountered in phasic partition. This extract was then chromatographed on silica gel G to separate carotenes and monohydroxy and dihydroxy pigments from non-pigmenting epoxy-xanthophylls. Magnesia chromatography of a portion of the ethanol extract followed by methanolic HC1 treatment of the xanthophyll fraction gave inconsistent results, apparently because of variable degrees of xanthophyll destruction by the HC1.
Collaborative Study of the Determination of Poly chlorinated Biphenyls in Paperboard
Authors: Finsterwalder Charles E 
Published: February 2020

Abstract
Eleven laboratories collaboratively studied a method for the determination of polychlorinated biphenyls (PCBs) (Aroclors 1242 and 1254) in paperboard, which involves alcoholic potassium hydroxide extraction, Florisil column cleanup, and electron capture gas-liquid chromatography. Blank paperboard spiked with 2 levels of each Aroclor and paperboard which had Aroclor 1242 incorporated during manufacture were analyzed. Average recovery of Aroclor 1242 at the 12.5 ppm level was 80.8%; at the 8.2 ppm level, 87.8%. Average recovery of Aroclor 1254 at the 12.3 ppm level was 87.0% ; at the 8.9 ppm level, 85.4%. The mean recovery of Aroclor 1242 from the specially prepared paperboard was 5.6 ppm, with a standard deviation of 15.8%. The method has been adopted as official first action.
Effects of Feeding Penicillin to Chickens
Authors: Katz Stanley E , Fassbender Carol A , Dinnerstein Paula S , Dowling John J 
Published: February 2020

Abstract
The feeding of penicillin to broilers and laying hens did not result in the deposition of any penicillin activity in the blood, muscle, liver, kidneys, or eggs. About 9 8% of the penicillin activity was destroyed in the upper portion of the intestinal tract with very little activity reaching the small intestine. When penicilloic acid, one of the degradation products, was fed to broilers it stimulated the development of lactosefermenting organisms in the intestinal tract, which showed antibiotic resistance as reflected by the streptomycin and tetracycline resistance markers.
Collaborative Study of a Modified Resazurin Test for Estimating Bacterial Count in Raw Maple Sap
Authors: Kissinger John C 
Published: February 2020

Abstract
A modified resazurin test technique for rapid estimation of bacterial counts in maple sap was studied in 13 collaborating laboratories. Statistical analysis of the collaborators' results indicates that this method can rapidly identify heavily contaminated sap which would yield low grade sirup or would be unsuitable for sirup manufacture. The method has been adopted as official first action
Semiautomated Batch System for Fertilizer Screening Analyses
Authors: Whittier Philip C , Forster Ann , McKinney James 
Published: February 2020

Abstract
A system has been developed for screening large numbers of fertilizer samples for nitrogen, phosphorus, potassium, and magnesium. The basis of the system is an assemblage of instruments found in virtually all fertilizer laboratories, supplemented by some specialized automatic aliquoting equipment. The methods that were in current use in our laboratory were streamlined and used in the system. The system has enough flexibility that other methods and instruments can be readily adapted to it. By using this system, we have reduced handling and costs, increased efficiency and production, and eliminated much analytical error.
Simple, Rapid Digestion Technique for the Determination of Mercury in Sea Food by Flameless Atomic Absorption Spectroscopy
Authors: Krinitz Benjamin , Holak Walter 
Published: February 2020

Abstract
A rapid digestion technique, using a Teflon vessel, for mercury determination by flameless atomic absorption spectroscopy was collaboratively studied. Average recoveries of added mercury to samples of freeze-dried shrimp and blended frozen tuna (8 collaborators) were 92, 87, 100, and 9 8% for levels of 0.25, 0.30, 0.45, and 0.50 μg, respectively, with standard deviations of 0.030, 0.046, 0.048, and 0.067. The digestion technique has been adopted as official first action.
Survey of Corn for Fusarium Toxins
Authors: Eppley Robert M , Stoloff Leonard , Trucksess Mary W , Chung Choong W 
Published: February 2020

Abstract
Samples of the 1972 corn crop were collected in areas where the potential for Fusarium contamination of the corn was considered to be high or where known Fusarium damage had been reported. The 223 samples were collected in the spring following the crop year from terminal elevators or from stocks on hand at food processing establishments and were analyzed for zearalenone, anatoxins, and T-2 toxin by a modified multimycotoxin detection method. A rabbit skin bioassay was used to screen for possible T-2 toxin at levels below the chemical detection limits. Zearalenone was found in 17% of the samples (0.1-5.0 mg/kg); anatoxin was found in 5 samples (trace-10 μg/kg). A skin irritant was found in extracts from 93 of 173 samples by the rabbit skin bioassay. This effect may be due to the T-2 toxin or some other mycotoxin.
Spectrofluorometric Determination of Lasalocid Sodium in Finished Feeds and Premixes
Authors: Osadca Modest , Araujo Mercedes 
Published: February 2020

Abstract
A simple, rapid, and sensitive chemical method is described for determining lasalocid sodium in finished poultry feeds and premixes. The drug is extracted with ethyl acetate directly from premixes and after a brief treatment with pH 4.7 buffer from finished feeds. Lasalocid sodium concentration is measured spectrofluorometrically and a correction for nonspecific fluorescence is determined after formation of a lasalocid- boric acid complex. Replicate assays of typical poultry mashes and pellets containing about 0.0075% lasalocid sodium yielded coefficients of variation of 2.8 to 5.0%. Average recovery of lasalocid sodium added in the laboratory at 0.0037, 0.0075, and 0.0112% was 90% with a pooled standard deviation of ±1.86%.
Determination of the Herbicide Isopropalin in Technical Grade Material and in Formulations
Authors: Dean Decker Oliver , Frank Richard 
Published: February 2020

Abstract
Two methods are described for the determination of isopropalin (2,6-dinitro-N,N-dipropylcumidine) in technical grade material (a concentrate in xylene) and emulsifiable concentrate formulations. Samples measured spectrophotometrically are purified by Florisil column chromatography. Samples measured gas chromatographically are dissolved in chloroform, mixed with the internal standard, and then injected into a gas chromatograph equipped with a flame ionization detector.
Collaborative Study of a Spectrophotometry Method for the Determination of Sorbic Acid in Fresh Dairy Products
Authors: Wilamowski George 
Published: February 2020

Abstract
A collaborative study has been completed on the determination of sorbic acid in 2 dairy products by a spectrophotometric method. Mozzarella cheese and cold pack cheese food were analyzed for sorbic acid. The sorbic acid was extracted from the dairy products with metaphosphoric acid and partitioned into a petroleum ether-anhydrous ether mixture. The concentration of sorbic acid was determined from its absorbance at 250 nm and its presence was confirmed by the disappearance of this absorbance maximum after shaking the ether solution with aqueous permanganate. The results obtained in the 10 collaborators’ laboratories were statistically evaluated. The average per cent recovery of sorbic acid in mozzarella cheese was 93.6—95.6 and in cold pack cheese food 90.7—101.9. A comparison was also made between the extraction procedure and the AOAC colorimetric method for sorbic acid in cold pack cheese food. The AOAC method had lower variability and higher per cent recovery for this product. The spectrophotometric method has been adopted as official first action as a screening procedure for sorbic acid in fresh dairy products.
Comparison of Culture Methods for Detection of Salmonella in Dried Active Yeast
Authors: Wilson Clyde R , Poelma Paul L , Andrews Wallace H 
Published: February 2020

Abstract
An improved procedure has been developed for the isolation of Salmonella from dried active yeast. Examination is presently made with a procedure employing pre-enrichment in 1% tryptone broth using a sample-broth ratio of 1:5, with subsequent transfers to selenite cystine (SC) broth and tetrathionate (TT) broth before streaking onto selective agars. The new method employs trypticase soy broth as the pre-enrichment medium using a samplebroth ratio of 1: 10, and subsequent transfers to lauryl sulfate tryptose (LST) broth and TT broth before streaking onto selective agars. The most significant points of change are samplebroth ratio and substitution of LST broth for SC broth. After a 24 hr pre-enrichment period, most probable numbers of the 5 Salmonella serotypes tested with the present procedure ranged from 13 × 103 to 7 × 105/ml compared with 13 × 106 to 49 × 107/ml using the new procedure. An incompatibility between active yeast and SC broth resulted in marked inhibition of 4 of the 5 Salmonella serotypes tested. LST broth was found to be highly productive for Salmonella growth and can be used in place of SC broth because of the absence of a large bacterial flora in dried active yeast. TT broth is retained as one of the selective broths in the event gross contamination is encountered and Salmonella becomes overgrown by non-salmonellae in the LST broth.
Collaborative Study of a Column Chromatographic Method for the Determination of Polythiazide in the Presence of Vanillin
Authors: Raymond Fazzari F , Levine Joseph 
Published: February 2020

Abstract
Polythiazide is eluted from a sulfanilic acid column with isooctane-ether solvent. The eluting solvent is then removed and the polythiazide is determined spectrophotometrically in methanol at about 268 nm. Vanillin is retained on the column as a Schiff’s base formed with the sulfanilic acid. The method was collaboratively studied by 9 analysts. The average per cent recovered and standard deviation for polythiazidevanillin preparations was 100.7±2.0. The method has been adopted as official first action.
Detection of Cashew Nut Shells in Coffee, Tea, and Chicory
Authors: Sengupta Pratima , Sen Asit R , Ghoshdastidar Nomita , Roy Bidhan R 
Published: February 2020

Abstract
Thin layer chromatography has been investigated for the identification of cashew nut shell, one of the common adulterants in ground coffee, tea, and chicory. The ether extract of the sample is applied to silica gel C plates and developed with benzene-dioxane-acetic acid (90+25+4) . Cashew nut shell shows 3 distinctive spots (Rf 0.7, 0.54, and 0.34) with diazotized benzidine which are totally absent in tea, coffee, and chicory. The spots have been identified as anacardic acid, cardol, and anacardol, respectively.
Differentiation of Caraway, Coriander, and Cumin by Study of Their Volatile Oils, Using Thin Layer Chromatography
Authors: Sen Asit R , Sengupta Pratima , Mondal Alpana , Roy Bidhan R 
Published: February 2020

Abstract
A rapid thin layer chromatographic test has been developed to differentiate caraway, coriander, and cumin. Samples are steam-distilled and 1% solutions of the volatile oils are chromatographed on silica gel G plates, using benzene- chloroform ( l+l ) as the solvent system. After exposure to iodine vapor, characteristic spots develop which can be used to distinguish and differentiate caraway, coriander, and cumin.
Determination of Methyl Salicylate in Root Beer
Authors: Markus John R 
Published: February 2020

Abstract
Root beer samples were analyzed for methyl salicylate by 17 laboratories, using the official final action AOAC method, 12.046-12.051. In this method, after the sample is distilled, methyl salicylate is extracted from the distillate with chloroform, and the compound is determined by gas-liquid chromatography. Recoveries of added methyl salicylate, 0.395 mg/ml, ranged from 0.349 to 0.428 mg/ml, with an average of 0.392 mg/ml. The average standard deviation and coefficient of variation were ±0.022 and 5.69%, respectively. On the basis of this study, procedural changes were recommended for method 12.046-12.051. They have been incorporated into the 12th Edition of Official Methods of Analysis.