bluuebunny/crossref_metadata_2025_split huggingface dataset:
Confirmation of Pesticide Residue Identity. II. Derivative Formation in Solid Matrix for the Confirmation of DDT, DDD, Methoxychlor, Perthane, cis- and trans-Chlordane, Heptachlor, and Heptachlor Epoxide Pesticide Residues by Gas Chromatography
Authors: Y Chau Alfred S , Lanouette M 
Published: February 2020

Abstract
A new approach has been developed for the simultaneous confirmation of DDT-type compounds, chlordanes, heptachlor, and heptachlor epoxide. Derivatives are formed by a solid matrix derivation technique in alumina/KOH and alumina/potassium tert.-butoxide. It is compared with the previously reported solution derivation technique. The high yield and simplicity of the present procedure should be useful in routine analysis, particularly for samples with a low concentration of the parent pesticide.
An Evaluation of a Buffered Agar Method for the Assay of Neomycin Sulfate in Feeds
Authors: Williams B J , Mayerhofer H J 
Published: February 2020

Abstract
The AOAC method for the assay of neomycin sulfate in feeds, 38.192–38.195, was modified by buffering the base and seed agar at pH 8.0 with tris (hydroxymethyl) aminomethane and deleting calcium chloride from the medium. Commercial feeds were assayed by both the modified and official AOAC methods and results were compared. The modified method was 2.64 times more sensitive than the AOAC method. The mean concentration of neomycin sulfate estimated by the modified method was 119.7% of that estimated by the AOAC method (significant at p &lt; 0.01). Differences in method variability were not statistically significant at the 1% level. Linear correlation between the logarithms of neomycin concentrations and zone diameters was excellent for both methods, and the slopes of their regression equations were approximately equal.
Fast Screening Method for Detection of Aflatoxin Contamination in Cottonseed Products
Authors: Cucullu Alva F , Pons Walter A , Goldblatt Leo A 
Published: February 2020

Abstract
The detection method incorporates a 3 min blender extraction of the sample with aqueous acetonitrile, followed by partition of aflatoxins from an aliquot of the extract into benzene to effect a 4-fold concentration of the aflatoxins. A millicolumn (4 mm id × 20 cm long) filled with zones of acidic alumina (1.5 cm) and silica gel (9 cm) is placed in a portion of the benzene extract and the column is developed 5 min in chloroform-acetonitrile-2-propanol. Aflatoxins are detected by the presence of a sharp blue fluorescent band about 1 cm above the alumina zone when the developed column is examined under longwave ultraviolet light. Total analysis time is 15 min, and sensitivity of the method is in the range of 10–20 μg total aflatoxins (B1 + B2)/kg. An indication of the approximate contamination level can be obtained from the intensity of the fluorescent aflatoxin band.
Spectrophotometric Determination of Pyrantel Tartrate in Soybean Premix and Swine Feeds
Authors: Lynch M J 
Published: February 2020

Abstract
Spectrophotometry methods are described for the determination of the anthelmintic agent pyrantel tartrate in soybean premix and medicated swine feeds. In each method, pyrantel is separated into chloroform as the ion pair with perchlorate or iodide anions and recovered from the solvent by extraction with O.1N HCL . The pyrantel content of this aqueousacid extract is determined by 2-component UV absorption spectrophotometry. These methods are specific for the determination of the pyrantel content of premix and feeds containing 2 potential degradation products: 1,4,5,6-tetrahydro-l-methyl-2-(cis-2-(2-thienyl)vinyl)py-rimidine and (E)-N-(3-methylaminopropyl)-2- thiopheneacrylamide. Pyrantel recoveries ranged from 96 to 101% in 8 premix blends, and 94 to 104% in 7 feed samples. Coefficients of variation ranged from 1.9 to 4.2% in premix and 1.8 to 7.6% in feed. No significant interference was encountered by unmedicated premix or feed samples.
Gas-Liquid Chromatographic Estimation of Sucrose Diacetate Hexaisobutyrate in Soft Drinks
Authors: Conacher H B S , Chadha R K 
Published: February 2020

Abstract
A rapid screening procedure is presented for the estimation of sucrose diacetate hexaisobutyrate (SAIB) in soft drinks. After extraction, SAIB is analyzed directly by gas-liquid chromatography, using trimyristin as internal standard. Recoveries of SAIB from drinks fortified with this compound ranged mainly between 94 and 98%, with a high of 104%. The analysis of 10 commercial citrus-based drinks showed 5 drinks to contain SAIB in the 12–14 nig/10 fluid oz range; none was detected in the other drinks.
Gas-Liquid Chromatographic Determination of Vitamins D2 and D3 in Infant Formulas and Feeding Preparations
Authors: M Touw H D , C KRöSE B M , Molenaar H M 
Published: February 2020

Abstract
A method is described for the isolation and quantitative GLC determination of vitamins D2 and D3 individually in infant formulas and tube feeding preparations. Saponification, elimination of sterols, extraction, and Celite column chromatography are done according to the procedure of Eisses and De Vries. However, thin layer chromatography on Adsorbosil and GLC with a 2% OV-17 column are used for cleanup and determination, respectively. The average recovery of added vitamin D3 (200%800 units/60 g solid sample) was 61.0±2.3%. When the internal standard addition technique was used, recovery improved to 101.3±6%.
IUNS-AIN Nomenclature for Vitamin E
Authors: Ames Stanley R 
Published: February 2020

Abstract
An improved new nomenclature system for the biologically and nutritionally important stereoisomers and mixtures of stereoisomers of vitamin K has been proposed. The term vitamin E is used as the generic descriptor for biologically active tocol and tocotrienol derivatives. α-Toeopherol, formerly (d-α-tocopherol, refers specifically to the isomer of trimethyltocol that occurs naturally, All-rac-α-tocopherol, formerly (dl-α-tocopherol, refers to the equimolar mixture of the 8 possible stereoisomers of α-toeopherol obtained by synthesis from racemic isophytol. 2DL-α-Tocopherol, also formerly (dl-α-tocopherol, refers to the equimolar mixture of the 2 C-2 diastereoisomers of a-tocopherol obtained by synthesis from natural phytol. 2L,-α-Tocopherol, formerly l-α-tocopherol, refers to the C-2 epimer of a-tocopherol. Both the General Assembly and the Gouncil of the International Union of Nutritional Sciences (IUNS) and the Council of the American Institute of Nutrition (AIN) have endorsed these proposals. The new IUNS-AIN nomenclature for vitamin E has been adopted as official first action. In addition the official first action method for α-tocopherol and α-tocopheryl acetate, 39.A01–39.A14, has been adopted as official final action.
Application of Atomic Absorption Spectroscopy to Plant Analysis. I. Comparison of Zinc and Manganese Analysis with Official AOAC Colorimetric Methods
Authors: Smith D L , W G Schrenk 
Published: February 2020

Abstract
A rapid and simple atomic absorption spectroscopic method has been developed for determining zinc and manganese in plants. The method has been applied to sample solutions containing 0.2–1.4 μg zinc/ml and 0.4–2.4 μg manganese/ml. Operating conditions for performing the analyses have been established for the Jarrell-Ash tri-flame burner (air-acetylene or nitrous oxide-acetylene flame) and the Beckman total consumption burner (oxygenacetylene flame). Variation of gas flow to t he burners did not significantly affect the absorption signals; however, the current applied to the hollow cathode was found to be important for zinc analysis. No significant interferences were noted from other ions present in plants when the tri-flame burner was used, but potassium, sodium, and sulfate ions caused slight decreases in the zinc absorption and t h e phosphate ion produced as much as a 20% decrease in signal for the total consumption burner. Wet- and dry-ashing techniques produced similar results, but variations in some cases were somewhat greater than desirable. Per cent recovery of added zinc (10 or 20 μg) and manganese (12 or 24 μg) ranged from 87 to 106% with most results being near 100%. A comparison of the AOAC and atomic absorption methods i n dicates that the atomic absorption method is as reliable and accurate as the official AOAC colorimetric methods. The atomic absorption method is simpler and faster than the AOAC method.
Pepsin Digestibility Method for Animal Proteins: 1971 Collaborative Study
Authors: Gehrt Albert J 
Published: February 2020

Abstract
The official method for pepsin digestibility of animal proteins, 7.040–7.046, was modified in 1970 by isolating the indigestible residue by filtration instead of centrifuging. The modified method was adopted as official first action in 1970 for all animal proteins except poultry byproduct meal and hydrolyzed feathers, since several collaborators encountered slow filtering and high results with the last 2 items. During the past year, meat meal, blood meal, poultry by-product meal, and hydrolyzed feathers were studied by 20 collaborators, using the first action method unchanged except for inclusion of more detailed filtering instructions. No filtration difficulties were encountered and the agreement between collaborators was good for all products tested. Several collaborators obtained high results, due either to use of pepsin NF or to low incubation temperature. Use of pepsin with a 1:10,000 activity and proper incubation temperature yielded concordant results. The modified method has been adopted as official final action for all animal proteins except poultry by-product meal and hydrolyzed feathers and as official first action for these 2 products.
Determination of Lead in Fish by Atomic Absorption Spectrophotometry and by Polarography. I. Development of the Methods
Authors: Gajan Raymond J , Larry Damon 
Published: February 2020

Abstract
A method for the determination of lead in fish by atomic absorption spectrophotometry and polarography is described. The samples were dry-ashed at 500°C and dissolved in IN HC1; lead was determined by either method. Good agreement between atomic absorption spectrophotometry and polarography was obtained at levels of 1.0 to 10.0 ppm. Over this range the recoveries averaged 96.1% for polarography and 93.8% for atomic absorption spectrophotometry. Twelve species of fresh and salt water fish were analyzed.
Aflatoxins M1 and M2 and Parasiticol: Thin Layer Chromatography and Physical and Chemical Properties
Authors: Stubblefield R D , Shotwell O L , Shannon G M 
Published: February 2020

Abstract
A survey of known anatoxin solvent systems for resolution of aflatoxins M1 and M2 on TLC plates revealed that the best system for determining aflatoxins B1, B2, G1, G2, M1, and M2 is isopropyl alcohol-acetone-chloroform (5 + 10 + 85). Substitution of various alcohols for isopropyl alcohol in this system demonstrated that maximum resolution of M1 and M2 was achieved with n-amyl alcohol-acetone-chloroform (10 + 10 + 80); however, B1, B2, G1, and G2 migrated with the solvent front. When alcohol-chloroform (5 + 95) mixtures were investigated, n-propyl, n-butyl, and tert-butyl alcohol + chloroform resolved M1 and M2 best but did not separate B1, B2, G1, or G2. Molar absorptivities of both M1 and M2 were determined in methanol, chloroform, acetonitrile, and acetonitrile-benzene (2 + 98). Relative fluorescent intensities of aflatoxins B1, M1, and M2 were compared on both developed and undeveloped TLC plates. Fluorescent intensities of B1 and M1 on silica gel were nearly equal, and the intensity of M2 was 1.4–1.5 times that of the other 2 aflatoxins. Water adducts of anatoxin M1 and parasiticol were prepared. The diacetate adducts of parasiticol were formed by treatment with acetic anhydride and concentrated HC1. Monoacetyl derivatives of M1, M2, and parasiticol were obtained by treatment with pyridine and acetic anhydride. Good resolution of the water-addition derivatives of B1, G1, parasiticol, and Mi on TLC plates was achieved with isopropyl alcoholacetone-chloroform (5 + 10 + 85).
Rapid Method for the Quantitative Measurement of Numerous Pharmaceutically Important Amines
Authors: Matthew W Richard , Browne Howard C , Weber J Bex 
Published: February 2020

Abstract
A simplified variation of the bromothymol blue method has been used successfully to analyze numerous pharmaceutically important amines. A single benzene extraction of the yellow amine-dye complex is made possible by buffering the dye solution at pH 7.0 and by maintaining the organic-to-aqueous ratio at not less than 3:1. This procedure not only greatly reduces the analysis time but also makes possible the analysis of numerous aromatic amines by a simple single extractiondye method. Any variation in t h e solubility of the amine-dye complex is compensated for by the simultaneous determ ination of a known standard of equal volume. Total analysis time for a dissolved sample does not exceed 15 min. These factors make the method especially useful for the routine analysis of pharmaceutical products.
Determination of Residues from Herbicide iV-(l, 1- Dimethylpropynyl)-3, 5-Dichlorobenzamide by Electron Capture Gas-Liquid Chromatography
Authors: Abler Irving L , Gordon Charles F , Haines Linwood D , Wargo Joseph P 
Published: February 2020

Abstract
Terminal residues of N-(l,l-dimethyrpropynyl)- 3,5-dichlorobenzamide and/or its metabolites are determined by digesting the sample with sulfuric acid and methanol to convert residues to methyl 3,5-dichlorobenzoate. This compound is codistilled from the reaction medium, purified by chromatography on Florisil, and measured by electron capture gas-liquid chromatography. The method is sensitive to 0.01 ppm. A decline pattern for residues on alfalfa is given.
Modification of AOAC Method for Determination of Soluble Solids in Tomato Products
Authors: Lamb Frank C 
Published: February 2020

Abstract
The official first action method for soluble solids in tomato products, 32.008–32.010, was modified to permit the optional use of an ultracentrifuge to prepare samples for readings in a refractometer. Excellent agreement was obtained between the official method which specifies filtration and the centrifugation technique. Good agreement was also obtained between 2 laboratories using the centrifugation technique. The official method was modified to include the optional use of an ultracentrifuge for sample preparation.
Systematic Approach to the Detection of Explosive Residues. I. Basic Techniques
Authors: Washington Willard D , Midkiff Charles R 
Published: February 2020

Abstract
An analytical scheme, in several parts, dealing with the identification of explosives and incendiary destructive devices encountered in actual cases is described. Part I is introductory and is the first step taken in the examination of bomb debris for the various types of explosives and/or incendiaries. Examples and photographs of typical bomb residues are presented.
Automated Method for Extraction, Cleanup, and Gas Chromatographic Determination of Triazine Herbicides in Soil
Authors: Hörmann W D , Formica G , Ramsteiner K , Eberle D O 
Published: February 2020

Abstract
Complete automation of extraction, cleanup, and GLC determination of residue analysis of some important triazine herbicides in soils has been achieved. Manually sieved soil samples are continuously delivered to the system, which presents cleaned up extracts to an automated GLC injection system. Peak areas are calculated by a digital electronic integrator. The output of the integrator is connected to a teletype printer which generates both printed hard copy and a punched paper tape in standard ASCII code. This information is fed by a punchtape reader into a programmed Wang 700 desktop computer. Final analysis reports are printed by an attached typewriter. The system allows a 4-fold output of analytical results with half the personnel compared to manual analysis.
Tracheal Organ Cultures for the Bioassay of Nanogram Quantities of Mycotoxins
Authors: Cardeilhac P T , Nair K P C , Colwell W M 
Published: February 2020

Abstract
Tracheal organ cultures from day-old chicks can be used in a bioassay to detect nanogram quantities of several mycotoxins implicated in animal diseases. Mycotoxins assayed with the minimum amount detectable (ng) are as follows: anatoxins B1 (22), B2 (1367), and G1 (89); patulin (750); sporidesmin (139); sporidesmin B (163); sterigmatocystin (12); gliotoxin (85); and ochratoxin A (175). By using miniature tissue culture chambers the volume of toxin containing media bathing the explants is reduced to 0.1 ml. The test depends on a cytotoxic effect of the toxins and the 50% lethal concentration (LC50) is considered to be the minimum detectable concentration. Cytotoxic potencies of several mycotoxins vary in a manner similar to their toxicities to the intact animalas indicated by a comparison of the cytotoxic LC50 determined by bioassay to an LD50 for ducklings.
Spectroanalytical Parameters of Fungal Metabolites. I. Citrinin
Authors: Neely W C , Ellis S P , Davis N D , Diener U L 
Published: February 2020

Abstract
The spectral data of the fungal metabolite, citrinin, were investigated and prior work was reviewed. The analytically important concentration ranges for ultraviolet and fluorometric determinations were studied in 3 solvents. The limits of detection were also determined in the solvents as well as on thin layer chromatographic films. CHCl3 was judged to be the best medium for detection and analysis with a limit of detection of 2 × 10−9M. Ultraviolet absorption and fluorescence emission were linear functions of concentration between 1 × 10−6 and 1 × 10−3M and 4 × 10−9 and 2 × 10−5M, respectively. A quantum efficiency of fluorescence of 0.058 and a mean fluorescence lifetime of 1.52 nsec were calculated. Precautions necessary to avoid thermal decomposition and photodegradation of the sample are outlined.
Survey of Ethylenethiourea in Commercial Ethylenebisdithiocarbamate Formulations
Authors: Bontoyan W R , Bontoyan J. B. Looker , Kaiser T E , Giang P , Olive B M 
Published: February 2020

Abstract
Twenty-eight different ethylenebisdithiocarbamate commercial products were examined for ethylenethiourea (ETU), a degradation product of ethylenebisdithiocarbamates. All products contained ETU, which was identified by thin layer and gas-liquid chromatography, infrared spectrophotometry, and mass spectrography. The techniques and parameters for identification and quantitative measurement are described.
Colorimetric Assay of Citral and Citronellal in Volatile Oils
Authors: Karawya Mohamed S , Hashim Fayek M , Hifnawy Mohamed S 
Published: February 2020

Abstract
A specific colorimetric method has been devised for the determination of citral and citronellal in volatile oils in the presence of other constituents , particularly aldehydes and ketones. The method is based on the fact that the reddish color generally produced by Schiff’s reagent with aldehydes fades on t h e addition of methanolic KOH. On acidification with methanolic H2SO4, a permanent, measurable green color develops which is specific for citral and citronellal. Quantitative TLC, based on the color reaction above, was also developed for the determination of citral or citronellal in volatile oils. T h e results were compared with those obtained by the Egyptian Pharmacopoeia 1963 method.
Per Cent Fatty Acid Composition and Quality Differences of Chinook and Coho Salmon
Authors: Iverson John L 
Published: February 2020

Abstract
The fatty acid profiles of prime and “spent” (inferior quality) Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) have been determined. There are indications that the long chain monounsaturated acids are preferentially utilized by the migrating salmon. However, there may be larger generic and specific run variations that preclude the use of a fatty acid compositional approach to differentiate between prime and spent salmon.
Determination of Starch by Glucose Oxidase and Polarographic Measurement
Authors: Trop Moshe , Grossman Shlomo 
Published: February 2020

Abstract
A method for the determination of starch in foodstuffs is reported. Interferences which are sometimes encountered with titrimetric or spectrophotometric determinative steps are avoided. In the method, the starch is hydrolyzed to glucose and the glucose is selectively oxidized in the presence of glucose oxidase. The rate of oxygen absorption for the oxidation reaction is measured and related to the starch content of the foodstuff. Results are presented for wheat and potato flours, which are shown to contain 71 and 59% starch , respectively. The method is specific, accurate, simple, and rapid and is applicable to foodstuffs containing interfering substances which often preclude analysis by other means.
Determination of Iron in Low-Iron Diets by Colorimetric and Atomic Absorption Procedures
Authors: Davies Muriel I , Bush K , Motzok I 
Published: February 2020

Abstract
Colorimetric (sulfonated bathophenanthroline) and atomic absorption methods for the analysis of iron in low-iron diets (7–30 ppm used in the biological assay of iron) gave mean values which were not significantly different; however, the values obtained with atomic absorption were significantly more variable. Copper, phosphate, perchlorate, sulfate, and a mixture simulating some of the mineral constituents of the basal diet in concentrations occurring in digests of the basal diet did not interfere with color development.
Thin Layer Chromatographic Separation and Spectrophotofluorometric Determination of Thiabendazole Residues on and in Citrus
Authors: Norman S M , Fouse D C , Craft C C 
Published: February 2020

Abstract
A thin layer chromatographic (TLC)-spectrophotofluorometric method was developed for quantitative determination of thiabendazole on and in citrus. Whole citrus fruits are surface stripped with ethyl acetate and a concentrated aliquot is separated by TLC. Wholefruit blends, juice, oil, and dried citrus pulp cattle feed are extracted with ethyl acetate, partitioned into 0.1N HC1, and then partitioned into ethyl acetate-chloroform from an aqueous basic solution prior to TLC. Thiabendazole is eluted from the chromatogram with acidified methanol and the intensity of fluorescence is compared to standards similarly chromatographed and measured. The method is accurate in determining thiabendazole content ranging from 0.2 to 6 ppm. Recoveries of thiabendazole from fortified samples were 95–99% for surface strippings and 70–91% for rind and pulp extractives. No significant difference was found between residue values determined by the TLC method and by the Merck method. TLC eliminates citrus constituents which occasionally interfere with the Merck method.
Methods of Estimating Dietary Exposure of the General Population to Organochlorine Insecticide Residues: Diet Analyses 1965–1967
Authors: Mcgill A E J , Robinson J , Stein M 
Published: February 2020

Abstract
The amounts of organochlorine insecticides in the diet of the general population of Great Britain has been estimated by analyzing representative whole cooked meals. The methods of quantitation are briefly outlined and techniques suitable for qualitative confirmation of identity of these compounds are discussed. The estimated dietary intakes are compared with the food in other dietary surveys and, in the case of dieldrin, they are also compared with the amounts calculated from the concentrations of this compound in body fat and blood. The dietary intakes of dieldrin in 1965–1966 and 1967 were estimated to be 0.00030 and 0.00020 mg/kg/day, respectively, the difference being statistically significant. The maximum estimated intakes of total equivalent DDT were 0.0011 and 0.0014, respectively.