bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Pressure Liquid Chromatographic Determination of Furazolidone in Turkey Tissue
Authors: Hoener Betty-Ann , Lee Gloria , Lundergan William 
Published: February 2020

Abstract
A high pressure liquid chromatographic method for determining furazolidone in turkey tissue has been developed. Tissues are ground with methanol and centrifuged. For lower levels of furazolidone, 2—40 ppb, the supernate is evaporated to dryness and redissolved before it is injected onto the liquid chromatographic column. Using a reverse phase column and an ultraviolet absorption detector set at 365 nm, the assay is linear over the concentration range 2—400 ppb with a coefficient of variation of &lt;4%. Average recovery from fortified tissues was 96% with a coefficient of variation of 6% at the 50-400 ppb level, and 105% with a coefficient of variation of 11% at the 2—40 ppb level.
High Pressure Liquid Chromatographic Determination of the Five Major Alkaloids in Papaver somniferum L. and Thebaine in Papaver bracteatum Lindl. Capsular Tissue
Authors: Vincent Phillip G , Engelke Beatriz Ferreira 
Published: February 2020

Abstract
A high pressure liquid chromatographic isocratic procedure is described for determining and quantitating the 5 major alkaloids narcotine, papaverine, thebaine, codeine, and morphine in Papaver somniferum L. and thebaine in Papaver bracteatum Lindl. Other papaveraceous alkaloids, including salutaridine, oripavine, laudanosine, isothebaine, cryptopine, alpinigenine, narceine, protopine, and gnoscopine, were also quantitated. The values for morphine, codeine, and thebaine in P. somniferum were in agreement within 5—9% with values obtained by the United Nations Narcotics Laboratory by other methods. In contrast to previously reported procedures, the advantage of this method is that no precolumn or other purification other than solvent extraction of the capsular tissue is necessary. Isocratic chromatography alone on a single column resolved the 5 major alkaloids.
High Pressure Liquid Chromatographic Determination of Saccharides in Corn Sirups: Collaborative Study
Authors: Engel C Earl , Olinger Philip M 
Published: February 2020

Abstract
A liquid chromatographic method for quantitative analysis of saccharides in corn sirup was investigated. Fructose, glucose, and related saccharides are separated on an Aminex 50W-X4, calcium form, cation exchange column or, alternatively, on an Aminex Q15-S, calcium form, cation exchange column. Water is the solvent. All carbohydrate components in the sirup elute from the column, permitting normalized computation vs. synthetically prepared standards. The corn sirup samples are diluted to an approximate dry substance and injected directly into the chromatograph. When required, interfering ionic material is removed with the aid of a mixed strong acid-weak base ion exchange resin. The reproducibility and repeatability coefficients of variation for fructose (on samples ranging from 15 to 90% fructose) are 0.9 and 0.3%, respectively. The reproducibility and repeatability coefficients of variation for glucose (on samples ranging from 8 to 50% glucose) are 1.4 and 0.5%, respectively. The method has been adopted as official first action.
Thin Layer Chromatographic Determination of Ctrinin
Authors: Chalam Ramaswamy V , Stahr Henry M 
Published: February 2020

Abstract
A thin layer chromatographic (TLC) method is described for the determination of citrinin in feeds. Citrinin is extracted from feed with methanol and water, the mixture is made alkaline with 10% sodium carbonate, and the aqueous solution is filtered and extracted with chloroform to remove most of the interfering materials. The aqueous layer is acidified with 2N HCl and extracted with chloroform. The chloroform extract is concentrated and spotted on a thin layer chromatographic (TLC) plate which is developed in chloroform-acetoneethanol- water (60+40+10+1). The citrinin is viewed under ultraviolet light after TLC. Either visual or fiuorodensitometric quantitation is used. Recoveries of citrinin from various feed samples spiked at levels of 2.0–5 μg/g were 75–92%. The proposed method can detect 0.5 μg/g feed, including corn, silage, ready mixed feeds, and feed pellets.
Gas-Liquid Chromatographic Determination of 7-Nonalactone in Alcoholic Flavors and Beverages
Authors: Dyer Randolph H , Martin Glenn E 
Published: February 2020

Abstract
A gas-liquid chromatographic (CLC) method was developed for the quantitative determination of γ-nonalactone in alcoholic flavors and beverages. Other common lactones (heptalactone, octalactone, decalactone, undecalactone, and dodecalactone) were separated using the GLC procedure, and mass spectrometric confirmation of these compounds and γ-nonalactone was carried out. In addition, fresh coconuts were analγzed; no γ-nonalactone was found at a detection limit of 0.5 mg/L. Thirty-six samples of flavors and beverages were analyzed for γ-nonalactone; the results ranged from 5750 to &lt;0.5 mg/L.
Determination of Virginiamycin in Feeds
Authors: Ragheb Hussein S , Black Lisa J , Waisner Debra L 
Published: February 2020

Abstract
Virginiamycin was extracted from the feed by ethanol-pH 2.5 phosphate buffer (1+l). The pH during extraction was adjusted (when necessary) to between 4 and 5. Sample dilutions and the standard dose response line were prepared to contain ethanol-pH 6 phosphate buffer (2+8), and the test organism was Sarcina lutea. Three feeds (a poultry ration, a swine finishing ration, and a swine starter ration) showed virginiamycin recovery of 88.8–108.9% when standard solutions were added at concentrations of 4.54–90.8 g/ton. The coefficient of variation (4–20%) was larger for low potency feeds (10 g/ton) compared to the higher feeds (100 g/ton). Similarly, excellent recovery was obtained when the swine starter feed was fortified by a commercial premix. Amprolium, roxarsone, and monensin can be present at 20 times the concentration of virginiamycin with little or no interference in the antibiotic determination. Lasalocid at 10 times the concentration of virginiamycin caused a slightly positive bias (recovery, 107.4%).
Modification of the Neutral-Detergent Fiber Procedure for Cereals and Vegetables by Using α-Amylase
Authors: Mcqueen Ralph E , Nicholson James W G 
Published: February 2020

Abstract
Samples with a high starch content that were incubated at 40°C overnight (12-18 hr) in pH 7 buffer with bacterial α-amylase before determination of their neutral-detergent fiber (NDF) contents were easier to filter and had lower estimates of NDF and hemicellulose than when the conventional procedure was used. At neutral pH, bacterial a-amylase was more effective in this role than 2 common fungal amylase preparations. Pretreatment with pepsin at pH 1.8 also reduced the estimates of NDF content but some samples still proved difficult to filter. Bacterial α-amylase that was added during the initial step of the ccnventional procedure exhibited some activity even after boiling in neutral-detergent reagent for 30 min and promoted rapid filtration of the samples, but led to estimates that were higher than those obtained following overnight incubation at 40°C. The reported modification of incubating samples overnight with α-amylase promotes rapid filtration, and thereby gives more accurate NDF estimates and less analytical variation for samples of cereal grains and vegetables that have a high starch content.
High Pressure Liquid Chromatographic Separation of Rotenoids from Plant Extracts
Authors: Moring Stephen E , McChesney James D 
Published: February 2020

Abstract
The concomitant isolation, identification, and quantitative determination of rotenoids by high pressure liquid chromatography and ultraviolet and mass spectral analyses is presented. Plant samples are extracted with chloroform-methanol, subjected to a combination of solvent partitioning and silica gel open column chromatographic cleanup, and then chromatographed by HPLC reverse phase techniques. Concentrations of rotenone and deguelin are reported for Tephrosia virginiana (L.) Pers. and Amorpha canescens Persh.
Mass Spectrometric Identification and Gas-Liquid Chromatographic Determination of 2-Chloroethyl Esters of Fatty Acids in Spices and Foods
Authors: Heikes David L , Griffitt Kenneth R 
Published: February 2020

Abstract
The 2-chloroethyl esters of 5 fatty acids have been identified in spice and food samples by gas-liquid chromatography-mass spectrometry (GLC/MS). Twenty-four spice samples were analyzed for the 2-chloroethyl esters of fatty acids by AOAC official multiple residue pesticide procedures using CLC with microcoulometric detection. The esters of capric, lauric, myristic, palmitic, and linoleic acids have been identified at levels up to 1400 ppm. 2-Chloroethyl linoleate was the most abundant ester in all samples. Several foods analyzed by the same procedures showed levels of 2-chloroethyl linoleate as high as 35 ppm. Recoveries from fortified samples ranged from 84 to 98% for the various esters. A method using an acid-catalyzed esterification reaction was developed to rapidly determine the fatty acid content of these spices. CLC analysis with microcoulometric detection was used. Recoveries from fortified samples ranged from 92 to 110%. After 2 spice samples found to be free of 2-chloroethyl esters were fumigated with ethylene oxide, the level of 2-chloroethyl linoleate reached 77 ppm. All levels of 2-chloroethyl esters were confirmed by GLC/MS.
Collaborative Studies on Cytogenetic and Dominant Lethal Assays
Authors: Sheu Ching-Ju W 
Published: February 2020

Abstract
Two ire vivo cytogenetic studies and one dominant lethal study were jointly conducted by members of government, academic, industrial, and independent commercial laboratories between 1970 and 1975 to determine the validity and reproducibility of the techniques. The cytogenetic studies consisted of preparations and analyses of bone marrow cells from male rats for chromosome abnormalities. In the first study, participants from 4 laboratories jointly prepared slides at a Food and Drug Administration (FDA) laboratory according to a prescribed procedure and independently analyzed the slides in their own laboratories. In the second study involving 6 laboratories, a workshop was held at Dow Chemical Co. to reduce scoring differences and to develop a joint protocol. All participants then independently performed the exact procedure in their own laboratories, using animals from a common source. In the dominant lethal study involving 6 laboratories, a workshop was held at the FDA to discuss protocol and to practice the technique. All participants then independently conducted the study in their own laboratories using rats and test chemicals from common sources. In all 3 studies, significant interlaboratory variability existed, and the differences varied with the parameters analyzed.
Review of in vitro Test Systems Using DNA Damage and Repair for Screening of Chemical Carcinogens
Authors: Williams Gary M 
Published: February 2020

Abstract
Chemical carcinogens are mechanistically classified as genotoxic which interact directly with DNA, and epigenetic which cause chronic tissue injury, hormonal imbalance, and promotional effects. This review evaluates in vitro tests for their contribution to a battery for identifying genotoxic chemical carcinogens. In addition to bacterial mutagenic assays, nonspecific DNA damage/repair tests are recommended for screening chemicals, in particular the hepatocyte primary culture/DNA repair test.
Intercomparison Study on the Determination of Single Administration Toxicity in Rats
Authors: Hunter William J , Lingk W , Recht P 
Published: February 2020

Abstract
In 1977, the Commission of the European Communities initiated an intercomparison study to determine the single administration oral LD50 value in rats of each of 5 chemicals with the aims of comparing experimentation technologies, determining the degree of variation in the results and the various parameters used to establish the LD50 value, and establishing a common protocol for the determination of the LD50 value. Sixty-five laboratories in 8 countries took part in the first study. The significant variation in protocol may have led to the large interlaboratory variation observed in the results. Therefore, participating laboratories carried out a second study using a common protocol, preceded by a pilot study. A total of 100 laboratories in 13 countries participated. A majority of results of the second study are currently being analyzed, and the indications are that the interlaboratory variation has been significantly reduced.
Comparison of Studies on Saccharin and Sodium Nitrite
Authors: Taylor Jean M , Morgenroth Victor H 
Published: February 2020

Abstract
A review of long term animal studies of saccharin and sodium nitrite was undertaken to assess the effect of variability of selected protocol elements on the results obtained. These elements were divided into 4 general categories: design, including selection of test animals, basal diet, dosage form and doses of test substance, route of administration, and duration of exposure; observations, including gross observations during life and at necropsy, clinical tests, and histopathology; performance, including conduct of the test and animal husbandry; and analytical procedures, including chemical and statistical analyses. Because many of the protocol elements are not fully discussed in study reports, it was often impossible to determine what actually had been done. The review of various saccharin studies suggests that bladder tumors resulted following in utero exposure. In utero exposure with sodium nitrite did not appear to cause reticuloendothelial changes. The numerous variations in protocol elements in the nitrite studies precluded identification of a prime element responsible for the variation in reticuloendothelial changes observed. It can be concluded from this review that achievement of reproducibility in long term studies requires minimal variation of protocol elements for the new study.
Comparison of Stomacher and Waring Blendor for Homogenizing Foods to be Examined for Clostridium perfringens
Authors: Harmon Stanley M , Kautter Donald A 
Published: February 2020

Abstract
The Colworth Stomacher Model 400 homogenizer was compared with the Waring Blendor for preparing food homogenates to be examined for Clostridium perfringens. Forty-eight samples representing 6 different food types were inoculated with C. perfringens and examined by the AOAC official first action method for enumeration of C. perfringens in foods. Identical paired specimens of each food type were blended with the 2 devices, and plate counts were made as specified in the official first action method. The effects of frozen storage on plate counts were determined by examining 24 food samples that had been stored for 3 days at —68°C and homogenized by both devices. Results of a statistical analysis of the experimental data indicated no significant difference overall (P &gt; 0.05) in the plate counts of homogenates prepared with the Waring Blendor or the Stomacher 400, either before or after frozen storage of the food samples. However, the overall plate count average of the 48 samples was slightly higher with the Waring Blendor than with the Stomacher 400 homogenizer.
Extraction, Cleanup, and Quantitative Determination of Aflatoxins B1 and M1 in Beef Liver
Authors: Trucksess Mary W , Stoloff Leonard 
Published: February 2020

Abstract
A method for the determination of aflatoxin Bx in eggs was applicable for aflatoxin B1 in liver, but ineffective for aflatoxin Mx in liver because of poor recovery of added aflatoxin and interferences in thin layer chromatography. The method was modified by the addition of citric acid to the extracting solvent and ammonium sulfate to the extract solution for removing protein. The elution system for silica gel column cleanup was also changed by substituting methanol for acetone, and adding a step for confirmation of aflatoxin M1 identity. The method has been used successfully for survey and research on aflatoxin residues in animal tissues.
Aflatoxin Variation Among Corn Samples with Varying Ratios of Aspergillus flarws-Inoculated/Noninoculated Kernels
Authors: Lillehoj Eivind B , Calvert Oscar H , Kwolek William F , Zuber Marcus S 
Published: February 2020

Abstract
Aflatoxin levels and physical properties of corn kernels inoculated with Aspergillus flavus during development and noninoculated kernels were compared in samples with various proportions of the 2 kernel types. The relationship between mean toxin levels and associated standard deviations of 5 samples demonstrated a linear association from the lowest toxin in noninoculated corn through a mixture of 60% inoculated/40% noninoculated. However, at the highest toxin level in the 100% inoculated material, a reduction in sample variation was observed. Examination of individual kernel weights showed that inoculated kernels were distinctly lighter than noninoculated seed. A uniform grinding procedure of the samples yielded heterogeneous particle sizes based on the starting corn. The large particle fraction (&gt;500 μm) decreased from 100% noninoculated kernels through the mixtures to the 100% inoculated seed; particles below 150 &gt;m were most abundant in the ground samples from inoculated kernels. In addition, the density of particles within a size category varied; lower densities were observed in samples obtained from A. flavus-inoculated kernels.
High Pressure Liquid Chromatographic Determination of Chloramine-T in Food
Authors: Beljaars Paul R , Rondags Theo M M 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) method for determining chloramine-T (N-chloro-N-sodium-p-toluenesulfonamide) in foods such as ice cream, minced meat, and shrimp is described. Deproteinized samples are treated with sulfite to convert chloramine-T to p-toluenesulfonamide (p-TSA) and extracted, and HPLC analysis is performed on concentrated extracts. Sample extracts are chromatographed on a reverse phase 10 μm Lichrosorb RP-18 column with acetonitrile-water (10+90), and quantitated by an ultraviolet detector (220 nm) and digital integrator. The relationship between recorded peak area and concentration was linear to 0.600 μg p-TSA/μL. The detection limit was 2.5 ng p-TSA/μL, corresponding to a chloramine-T concentration of 0.8 mg/kg in samples. Recoveries of added chloramine-T were 88% for ice cream, 73% for minced meat, and 51% for shrimp. Precision data indicate a relative standard deviation of 1.54 and 2.14% for the complete analysis of ice cream with levels of 15 and 63 mg chloramine-T/ kg (n = 5 determinations), respectively. The HPLC method was applied to chloramine-T determinations in 62 ice cream, 25 minced meat, and 25 shrimp samples.
Further Study of the Spectrophotometric Determination of Capsaicin
Authors: Palacio José Jorge Ramos 
Published: February 2020

Abstract
This study has been undertaken to clarify the previous work on the determination of capsaicin so that the results will be more uniform. For a good colorimetric reaction, the ethyl acetate should have a low water content; 0.1% is optimum concentration for vanadium oxytrichloride. In samples with low Scoville rating, paprika pigment can interfere with the analysis. The absorbance due to this pigment has been studied to determine the absorbance due to capsaicin.
Modified Method for Carbadox in Feeds: Collaborative Study
Authors: Goras John T 
Published: February 2020

Abstract
The official first action method for carbadox in swine feed, 42.C01-42.C04, was modified in 2 respects. First, the samples were leached overnight at room temperature instead of boiled for 1 hr. This change avoided problems with overheating and excessive evaporation. Second, the dilution scheme for samples spiked with carbadox standard solution was changed to give absorbance values that were within the optimum working range of all types of spectrophotometers. The modified procedure was collaboratively studied by 21 laboratories. The repeatability standard deviation (σo) and reproducibility standard deviation (σo) were σ0 = 0.00029% and σx = 0.00056% (8.9% of grand mean) for feeds containing 0.00617% carbadox; and σo = 0.0012% and σx = 0.0019% (9.3% of grand mean) for feeds containing 0.0198% carbadox. The between-laboratory variance ratio was significant for feeds containing 0.0198% carbadox. The mean per cent of intent values for feeds containing 0.00617% carbadox and 0.0198% carbadox were 102% and 104%, respectively. In general, the statistical results were comparable to those previously obtained for the official first action method. Consequently, the modified procedure is not recommended as a replacement for the official first action method.
Infrared Spectrophotometric Method for Analysis of Guthion Insecticide: Collaborative Study
Authors: Cohen Charles J ,   Collaborators:, Audino J B , Byrne M , Grimes G S , Hanks A R , Jennings F A , Looker J , Minyard J P , Winstead G R , Winterle E R 
Published: February 2020

Abstract
A collaborative study on the assay of Guthion (azinphos methyl) has been conducted by 10 laboratories. Data were obtained on a 2 Ib/gal. liquid concentrate and a 50% wettable powder formulation. The procedure specifies extraction and/or dilution followed by infrared absorbance measurement at 654 cm-1. The method has been adopted as official first action.
Mycotoxins in Animal Feedstuffs: Sensitive Thin Layer Chromatographic Detection of Aflatoxin, Ochratoxin A, Sterigmatocystin, Zearalenone, and T-2 Toxin
Authors: Patterson Deryck S P , Roberts Basil A 
Published: February 2020

Abstract
Improvements have been made to a previously described multi-mycotoxin method that involved a membrane cleanup step. Using 2-dimensional thin layer chromatography and appropriate solvent systems, aflatoxin B1 can be detected in mixed feedstuffs and various ingredients at levels ranging from 0.1 to 0.3 μg/kg. Corresponding detection limits for ochratoxin A and sterigmatocystin are 5 to 20 μg/kg and for T-2 toxin and zearalenone 20 to 200 μg/kg.
Comparative Study of Two Methods for Extraction of Aflatoxin from Peanut Meal and Peanut Butter
Authors: Chang Henry H L , Vries Jonathan W De , Hobbs William E 
Published: February 2020

Abstract
The difference between the CB and Best Foods methods in extracting aflatoxins from peanut products has been studied. The CB method yields 60, 121, 35, and 22% higher results for aflatoxins B1, B2, G1, and G2, respectively for 4 samples of peanut meal and 6 samples of peanut butter studied. Both reverse phase liquid chromatography and thin layer chromatography were used to quantitate the extracted aflatoxins.
Detection of Admixtures of Turmeric, Curcuma longa Linn., with Curcuma aromatica Salisb. by Thin Layer and Gas-Liquid Chromatography
Authors: Raghuveer Kalyan G , Govindarajan Venkatesa S 
Published: February 2020

Abstract
Simple and definitive thin layer chromatographic methods are described for the detection of admixtures of Curcuma longa with Curcuma aromatica at the 5% levels. The tests are performed on hexane extracts, thus avoiding distillation of the volatile oil, and are based on the separation of high boiling sesquiterpene compounds by hexane or benzene. Chromatograms are sprayed with vanillin-sulfuric acid or Gibbs reagent to give distinct spots for C. aromatica which are absent from C. longa. Gas chromatography of the extracts also distinguishes the admixtures through a late-eluting peak for C. aromatica.
Elimination of the Hortvet Degree in Cryoscopy
Authors: Richardson Gary H 
Published: February 2020

Abstract
It is recommended that Hortvet degrees be replaced by Celsius degrees in official methods to prevent difficulties in interpretation of data on added water in milk, caused by differences in the 2 thermometers. At one calibration point, this difference amounts to &gt;3% added water in milk, and could affect the action level.