bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimations of Vitamin A Biopotency in Liquid Feed Supplements
Authors: Parrish D B , Aguilar Dalia 
Published: February 2020

Abstract
Liquid feed concentrates and supplements were analyzed for total vitamin A content, and relative biopotencies were calculated from maleic values determined on those products. The initial relative biopotencies were from 65 to 97% for concentrates and 57 to 85% for supplements. Even when total vitamin A content decreased, storage up to 47 weeks had relatively small effect on relative biopotencies. A single correction factor could not be applied to relate vitamin A analytical data to vitamin A biopotency. Small quantities of anhydroretinol, vitamin A ether, and other unidentified types of vitamin A were found in several liquid feed products. On some samples spectrophotometric determinations yielded values in the same general range as calculated values based on relative biopotencies, but in a few instances the relationship was poor.
Improved Extraction Technique for the Infrared Spectrophotometry Analysis of Dioxathion, Malathion, and Other Organophosphate Insecticides in Livestock Emulsion Dips
Authors: Czech Fred P , Evans George 
Published: February 2020

Abstract
Certain livestock emulsion dips of dioxathion, malathion, and other organophosphate insecticides are not amenable to complete extraction of active ingredient by previous methods employed in infrared spectrophotometric determination. Evidence is presented which indicates that the major interference is dirt or soil contributed to the emulsion by animals during dipping. An improved extraction technique is presented which obviates this difficulty; it is recommended as a standard substitute in infrared analysis of organophosphate livestock dips.
Determination of Mercury in Biological Materials
Authors: Jeffus M T , Elkins J S , Kenner C T 
Published: February 2020

Abstract
Mercury in biological samples is determined by digestion in nitric acid, sulfuric acid, and permanganate, followed by reduction and aeration for measurement by atomic absorption at room temperature. The average recovery is 95.8% with a standard deviation of 13.3%. The standard deviation, calculated from the difference between duplicates of 23 samples, is 0.063 μg mercury, which represents 9.4% of the average value of the samples. The method is simple and requires approximately 4 hr for completion. Mercury can be confirmed by adsorption on gold foil after maximum absorbance has been obtained during aeration.
Rapid Method for Detection and Identification of Synthetic Water-Soluble Coloring Matters in Foods and Drugs
Authors: Lehmann G , Collet P , Hahn H G , Ashworth M R F 
Published: February 2020

Abstract
A method is described for the rapid detection of coloring matters in foods. In this method, acid dyes from the substrate of foods (starch, pectins, sugars, and gelatin) are dissolved with ammonical alcohol, followed by acidification and adsorption of the dyes from solution onto polyamide powder. Protein-containing foods are treated with acetone to remove fat and water and to coagulate soluble protein. This yields a product which can be used as the filling in a newly designed chromatographic tube; the coloring matters can be eluted with ammoniacal alcohol and the protein remains on the column. Water-soluble forms of natural coloring matters such as chlorophyll, carmine, annatto, alkanna red, betanin, and grape juice red pigment can also be adsorbed on polyamide powder. Basic dyes are adsorbed on carboxymethyl cellulose. Since the coloring matters are eluted at room temperature, they are not expected to undergo irreversible changes during the procedure.
Rapid Screening Test for the Evaluation of Quaternary Ammonium Compounds by Triphenyltetrazolium Chloride Reduction by Microorganisms
Authors: Sitkiewicz Raymond J 
Published: February 2020

Abstract
A rapid screening test has been developed to determine killing dilutions of quaternary ammonium compounds. Two factors, Letheen broth as a quaternary ammonium compound neutralizer and triphenyltetrazolium chloride as a microbial growth indicator, resulted in a rapid test system for the evaluation of quaternary ammonium compounds. This rapid test system takes from 4 to 8 hr to complete as opposed to the 24 to 48 hr for other tests. A new germicide can be bacteriologically screened in one day.
Test to Determine Whether Shucked Oysters Have Been Frozen and Thawed
Authors: Gould Edith , Medler Michael J 
Published: February 2020

Abstract
An objective test is described that will detect whether refrigerated, shucked whole oysters have been frozen and thawed at any time. Latent forms of malic enzyme activity are solubilized by freezing and thawing and can be differentiated from the normally soluble form by their differing rates of electrophoretic migration under the conditions described in this paper. SuperchiUed (23°F) oyster meats showed the same latent malic enzyme activity as the frozen. A sharply discontinuous buffer system during the polyacrylamide gel electrophoresis and a carefully timed incubation period for the histochemical staining are essential to the test. In oyster meats stored at 34°F for up to 3 weeks, neither autolysis nor bacterial action was great enough to produce the enzymogram peculiar to oysters that have been frozen or superchilled and thawed.
Spectrophotofluorodensitometric Measurement of Ochratoxin A in Cereal Products
Authors: Chu Fun Sun , Butz Mary E 
Published: February 2020

Abstract
A spectrophotofluorodensitometric method for measurement of oehratoxin A on TLC plates has been described. The lower limit concentration of this method is 0.5–1.0 ng ochratoxin A/spot. A method including extraction and primary treatment for detection of ochratoxin A in cereal products has also been developed. The adequacy of this method is evident from the different recovery experiments. More than 85% of the added toxin was recovered in most analyses. The overall precision of the measurement was 3–4%. The sensitivity of this method was approximately 10–50 ppb (μg/kg).
Use of Tracheal Organ Cultures for Bioassay of Aflatoxins
Authors: Nair K P C , Colwell W M , Edds G T , Cardeilhac P T 
Published: February 2020

Abstract
Tracheal organ cultures from day-old chicks were used for the assay of aflatoxins. Ciliary epithelium in the organ culture was found to be highly sensitive to aflatoxins B1 and G1. Anatoxin B1, incorporated into the medium in which the organ cultures were established, readily caused distinguishable eytomorphological changes in 48 hr at a concentration of 0.2 μg/ml and complete cessation of ciliary movement at a concentration of 0.5 μg/ml. Anatoxin G1 produced the same effects, but at higher concentrations (0.5 μg/ml and 2.0–2.5μg/ml). The degree of cytomorphological changes of the ciliary epithelium in the organ cultures was proportional to the concentration of aflatoxins and the period of time exposed. A dose-response curve was developed for the period of observation. The technique is simple, reproducible, and inexpensive. The feasibility of developing this test system as a biological assay for the presence of aflatoxins and other mycotoxins in feeds and foodstuffs is being explored.
Determination of Oxygen and Carbon Dioxide in Medicinal Gas Mixtures by Gas-Solid Chromatography
Authors: Langham William S 
Published: February 2020

Abstract
A gas-solid chromatographic method is presented for the analysis of oxygen, oxygenhelium, and oxygen-carbon dioxide mixtures. The method utilizes a 16’ Porapak Q chromatographic column, hydrogen carrier gas, and a thermal conductivity detection system. It is applicable to the analysis of nitrogen, helium, argon, carbon monoxide, and nitrous oxide. Dry Ice conditions are required for the oxygen analysis; carbon dioxide is determined at ambient temperatures. Details for the assembly of a suitable chromatograph and a procedure for sampling gas cylinders are presented. Samples of medicinal gases were analyzed by the proposed method and by the Orsat absorption method. The results by both methods were in good agreement.
Isolation of Shigella from Foods
Authors: Fishbein Morris , Mehlman Ira J , Wentz Barry 
Published: February 2020

Abstract
Experiments based on adverse competitive ratios were undertaken in which minimal numbers of Shigella were inundated with high density competitive populations obtained from natural foods such as ground meat or crabmeat. The effects of oxygen tension and metabolites on Shigella growth were also examined. The limitations of the Shigella detection system were analyzed and defined and an extremely sensitive model for Shigella enumeration was devised for laboratory experimentation. By means of the new system, the study of Shigella recovery under competitive stress will be much simplified. It is recommended that the isolation procedures be studied further to improve their specificity.
6,6′-Oxybis(2-Naphthalenesulfonic Acid) in FD&C Yellow No. 6
Authors: Marmion Daniel M 
Published: February 2020

Abstract
6,6′-Oxybis(2-naphthalenesulfonic acid), DONS, is shown to be present in FD&C Yellow No. 6 by column chromatography and UV spectrophotometry.
Comparison of Some Cleanup Columns for Residue Analysis of Chlorinated and Phosphorus-Containing Pesticides
Authors: Versino B , van der Venne M-TH , Vissers H 
Published: February 2020

Abstract
A comparison is presented of 8 of the most widely used cleanup methods based on adsorption column chromatography for chlorinated and phosphorus-containing compounds and their metabolites. For chlorinated pesticides, all methods show equivalent efficiency and recovery. For phosphorus-containing compounds and metabolites, methods employing columns filled with adsorbent mixtures work better than “all-Florisii” columns.
Estimations of Vitamin A Biopotency in Dry Supplements and Premixes
Authors: Parrish D B , Aguilar Dalia 
Published: February 2020

Abstract
Vitamin A biopotency was estimated on 20 dry vitamin A supplements and premixes from maleic value determinations. Relative bio-potencies of most samples were 90% or higher; only one recently obtained premix and an older supplement were less than 84%. Thus, the data indicate that most of the vitamin A was in the all-trans form. The problem of true vitamin A value for the dry supplements and premixes is of less concern than for the liquid feed supplements analyzed previously, and relative biopotency calculations apparently are not needed on most samples.
Determination of Mercury in Fish by Flameless Atomic Absorption: A Collaborative Study
Authors: Munns R K , Holland D C 
Published: February 2020

Abstract
A collaborative study for the analysis of total mercury in fish is reported. The method is based upon a measurement of the volatilized mercury vapor by flameless atomic absorption. The fish muscle is digested with nitric-sulfuricperchloric acids. The mercury (II) is reduced with stannous chloride-hydroxylamine and then volatilized at room temperature in a stream of air. The air is pumped through a gas cell where the mercury vapor is measured by atomic absorption at 253.7 nm. Nine laboratories participated in the study. An overall mercury recovery of 83.5% and a standard deviation of 0.066 were obtained. Similar samples were analyzed by the official AOAC method. Results were erratic, with an overall mercury recovery of 46% and a range of 0 to 106%.
A Colorimetric Method for the Quantitative Determination of Total Aldehydes in Cold-Pressed Orange and Grapefruit Oils
Authors: Dougherty Marshall H , Petrus Donald R 
Published: February 2020

Abstract
A colorimetric method for the quantitative determination of the aldehyde content of cold-pressed orange and grapefruit oils is described. The method employs N-hydroxybenzenesulfonamide and may be conducted in conjunction with the analyses of citrus essences and juices for total aldehyde content, since the same standards and reagents are used. Data for reproducibility, standard curves, and sample analyses are given and discussed. Equations are given for conversion of results to per cent decanal.
Collaborative Study for the Determination of Nequinate in Feeds
Authors: Cox Phillip L 
Published: February 2020

Abstract
A collaborative study has been conducted on a previously reported method for the determination of nequinate in feeds. The drug is extracted from feed with 1% formic acid in chloroform and measured spectrofluorometrically after dilution with chloroform and the addition of methanesulfonic acid. Eight collaborators participated in the study, analyzing 7 different feeds. The average coefficient of variation for the study was 5.3%. The method is recommended for adoption as official first action.
Collaborative Study of a Gas Chromatographic Method for Ipronidazole in Feeds
Authors: De Ritter Elmer , Osadca Modest 
Published: February 2020

Abstract
A GLC method for ipronidazole in turkey feeds at levels of 0.0033, 0.0066, and 0.0099% was studied by 7 laboratories. Ipronidazole is extracted by shaking with warm 0.2N HCl. An aliquot of the extract is made alkaline and the ipronidazole is extracted with benzene and diluted further for GLC with an electron capture detector. The method is simple, rapid, and free from interference. Agreement between laboratories was very satisfactory; coefficients of variation were 7.1, 3.0, and 8.0%. Recoveries of ipronidazole were 97, 96, and 99%. It is recommended that the method be adopted as official first action and that the study be continued.
A Sensitive Gas Chromatographie Determination of Diethylstilbestrol in Animal Feeds
Authors: Donoho A L , Decker O D , Koester J , Koons J R 
Published: February 2020

Abstract
A GLC method is described for the determination of diethylstilbestrol (DES) in feeds and supplements containing 0.00022-0.0022% DES (2-20 g/ton). A 20 g sample is extracted with an ethanol-chloroform mixture and an aliquot containing 1 or 2 μg DES is taken for assay. The extract is washed with pH 10.5 carbonate buffer and the DES is partitioned into 1N NaOH. After this purification, the DES is reacted in base with dichloroacetyl chloride and the esters formed are simultaneously extracted into chloroform. The DES esters are measured by GLC, using a 5% UC W-98 column and electron affinity detection. Dioctyl tetrachlorophthalate is used as internal standard. The coefficients of variation are on the order of 5% in supplements and 10% in complete feeds.
Confirmation of Organophosphorus Pesticide Residues at Nanogram Levels by Two-Dimensional Thin Layer Chromatography
Authors: Gardner Albert M 
Published: February 2020

Abstract
A new 2-dimensional TLC technique is described in which organophosphorus pesticides are oxidized after 1-dimensional development on silica gel G plates before development in the second direction. This system is more specific as it involves chromatography of both the parent pesticide and the subsequent derivative. Bromine vapor is used for oxidation; horse serum cholinesterase and indoxyl acetate are used for detection. Rf values and minimum detection levels of 26 organophosphorus pesticides are tabulated. Eighteen pesticides are identified at the 0.01 ppm level in fortified crops.
Modification of the Official AOAC Method for Fat Content Determination of Dried Egg Yolk
Authors: Navarro J G , Borie F , Barrientos V , Caiozzi M 
Published: February 2020

Abstract
Fatty acid residues higher in weight and of different composition than those obtained by the official AOAC method, 17.011(b), are obtained when the following 2 changes are made in this method for the determination of fat in dried egg yolk: (1) the replacement of the recommended HCl (4 + 1) solution by HCl (1 + 1) solution and (2) a mild boiling of the sample-HCl mixture for 20 min instead of heating in a boiling water bath for 30 min. Each yolk fat determination was followed by a GLC fatty acid analysis.
Collaborative Study of the Extraction of Light Filth from Crude and Refined Papain
Authors: Brickey Paris M 
Published: February 2020

Abstract
A method for the extraction of light filth from crude and refined papain has been developed. The product is solubilized by boiling in water, followed by wet sieving. Depending upon the amount of residue remaining on the sieve, the product is either transferred directly to filter paper(s) or trapped off in a Wildman trap flask. Collaborative recoveries of spiked insect fragments and rodent hairs were 94 and 92%, respectively. The method has been adopted as official first action.
Collaborative Study of a Method for the Extraction of Light Filth from Ground Chicory
Authors: Thrasher J J 
Published: February 2020

Abstract
Collaborative results are presented on a new method for light filth in ground chicory. A comparison of the new method and the official method, 40.007(b), indicates that recoveries of spiked larvae and adult insects were approximately equal for the 2 methods. However, average recovery of rodent hairs by the proposed method was 86% while rodent hair recovery by the official method was 55%. The new method utilizes detergent digestion and wet sieving followed by flotation with paraffin oil from 40% isopropanol. It is less time consuming to perform and cleaner filter papers are obtained. The new method has been adopted as official first action.
Collaborative Study of a Method for the Recovery of Acid-Insoluble Residues (Soil) in Frozen Spinach and Strawberries
Authors: Winter F H 
Published: February 2020

Abstract
A method is described for determining soil in frozen fruits and vegetables. The frozen contents of the package are transferred to a plastic bag, thawed in warm water, removed, blended, and placed in a 2 L beaker. Water is added, the contents are swirled, and, after 3 decantations of the supernatant, the residue is collected on a filter and ashed. After HCl treatment, the residue is ashed once more and weighed. The method was applied to over 50 samples of spinach and strawberries. The standard deviation between 12 collaborators, who analyzed 4 samples each, varied from 0.0051 for spinach to 0.0087 for strawberries. The method has been adopted as official first action.
Assay of Ipecac and Its Preparations. II. Collaborative Study
Authors: Sharkey Margaret F , Smith Edward , Levine Joseph 
Published: February 2020

Abstract
A method for the determination of 2 major alkaloids in ipecac sirup and powdered ipecac root was subjected to collaborative study. A 4-column chromatographic procedure is used for the isolation of emetine and cephaeline, which are measured individually by UV absorption. Two commercial sirups were employed as samples. The powdered root samples were representative of the different ratios of emetine and cephaeline occurring in the different species. The collaborative results were good: Standard deviations ranged from 0.024 to 0.066 for the powdered samples and from 1.11 to 2.77 for the sirup samples. The methods have been adopted as official first action for determination of emetine and cephaeline in ipecac sirup, powdered root, and fluidextract.
Gas-Liquid Chromatographic Assay for Salicylamide, Acetaminophen, and Caffeine Mixtures, Using On-Line, Computerized Real-Time Data Acquisition
Authors: Alber Larry L , Overton Mack W , Smith Donald E 
Published: February 2020

Abstract
Salicylamide, acetaminophen, and caffeine in drug formulations can be separated and quantitatively measured by GLC. Amobarbital and cyclizine are used as internal standards; the 4’ GLC column contains 3% OV-17 on Gas Chrom Q. The signal from the KCl thermionic detector is amplified and fed directly into the analog-to-digital converter of a PDP 12A LINC System computer. Results by the computer are compared to manual peak height measurements for 6 commercial preparations injected in duplicate and to results obtained from a UV procedure.
Identification of Phenothiazine Derivatives and Analogs by X-Ray Diffraction. I. Examination of Pure Compounds
Authors: De Leenheer A , Heyndrickx A 
Published: February 2020

Abstract
X-ray diffraction data for phenothiazines and chemically related compounds have been obtained by the Debye-Scherrer powder technique with photographic recording. Classification of compounds according to their X-ray data has been made, using the “innermost line index” method. The results obtained serve as reference data with absolute specificity for identification purposes.
Missouri Automated Method for Total Nitrogen in All Fertilizers
Authors: Gehrke Charles W , Wall Larry L , Killingley John S , Inada Kazuyoshi 
Published: February 2020

Abstract
An automated spectrophotometric method, utilizing Technicon AutoAnalyzer modules, has been developed for the analysis of nitrogen in fertilizers. The continuous digestor, which was found to effectively digest organic materials in solution after the reduction step, is coupled with an automated colorimetric system. This colorimetric system employs the ammonia-phenate-hypochlorite reaction. The fertilizer samples are reduced manually via the comprehensive nitrogen method (CNM). The sampling rate chosen is 30 cups/hr (6 reference standards included) which yields an effective analysis rate of 24 samples/hr. The impinger mixer at the exit end of the digestor helix is replaced with a jacketed double-mixing coil and an AO glass fitting for a more stable baseline and improved precision. Manganous ions at a concentration of 5.0 ppm introduced into the color development manifold as a catalyst give a significant increase in sensitivity. When commercial fertilizer samples were analyzed with the automated system, consistently low results were obtained for some samples as compared to results obtained by the AOAC CNM. However, 0.01M potassium sodium tartrate in the color development manifold provides sufficient complexing potential to eliminate the effect of interfering ions. One hundred commercial fertilizer samples including solid, liquid, and suspension fertilizers were analyzed by the Missouri automated nitrogen method. The results agreed well with the results obtained by multiple independent analyses by the AOAC CNM. Details of the automated system, sample preparation, reagent concentrations and preparation, and experimental data are given.
Effect on Eggs of Applications to Poultry of Pesticide Formulations Contaminated with Chlorinated Hydrocarbons
Authors: Thomas Ronald F , Medley Jerry G 
Published: February 2020

Abstract
This study shows the results of intentional contamination of 3 pesticide formulations for application to poultry. Formulations used were 1% rotenone dust with 0.005–0.3% of both DDT and dieldrin contamination, 5% carbaryl dust with 0.01–0.10% of both DDT and dieldrin contamination, and 50% malathion liquid with 0.1–0.3% chlordane contamination. The DDT and dieldrin were added as a mixture. One group of hens was treated with the rotenone dust, one group with the carbaryl dust, and a third group with the 50% malathion liquid. Residues in eggs of both DDT and dieldrin resulted from proper use of rotenone and carbaryl and were increased by doubling the amounts of dust applied to the hens. Chlordane residues, if present, were below detectable levels. Treated hens from each of the 3 groups were artificially inseminated and some eggs were incubated, but no apparent inhibition of hatchability occurred following use of the levels of contamination employed in this study.
Collaborative Study of Modified Elmore Method for Mercury in Formulations
Authors: Launer James E 
Published: February 2020

Abstract
The titrimetric method for mercury described by Elmore in 1946 was modified and collaboratively studied with formulations containing 6.7% phenylmercury urea in one test pair and 1% mercuric nitrate in another test pair. Mercury is determined in diluted solution, following reflux at 30 drops/min with fuming H2SO4-red fuming HNO3, by titration with standard thiocyanate solution, using ferric alum as indicator. The method is not applicable in presence of large quantities of chlorine-bearing materials. Single determinations on 4 samples by 14 collaborators showed that the standard deviation estimation of random error was 0.058 for phenylmercury urea and 0.004 for mercuric nitrate. Standard deviation estimates of systematic error were 0.048 and 0.009, respectively. The method has been adopted as official first action.