bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microbial Assay Systems for Determining Antibiotic Residues in Soils
Authors: Katz Jack M , Katz Stanley E 
Published: February 2020

Abstract
Procedures tor the assay or bacitracin, chlortetracycline, erythromycin, oxytetracycline, and tylosin residues in soils are presented. Except for tylosin, 1 μg antibiotic/g soil could be detected and measured. Recoveries of bacitracin (43.0-83.9%) averaged 60.3% and were unaffected by clay, sand, or silt content. Recoveries of chlortetracycline (40.0-116.0%) averaged 63.9% with no apparent relationship between recoveries and soil composition. Recoveries of oxytetracycline (30.8-100.0%) averaged 64.5% and were affected by silt and clay content. There was an inverse relationship between recoveries of tylosin and clay and silt content. Recoveries ranged from 6.5% in a soil containing 23.7% silt and 16.3% clay to 74.1% in a soil containing 96.3% sand. Recoveries of erythromycin were similarly related to clay and silt content, with recoveries averaging 36.3% in soil containing 40% silt and clay and 76.0% in soil containing 96.3% sand. Penicillin could not be recovered from soils because of its instability. Streptomycin was irreversibly adsorbed and could not be extracted from any soil studied.
Rapid Method for Extraction and Reverse Phase Liquid Chromatographic Determination of Paraquat Residues in Water
Authors: Ahmad Ijaz 
Published: February 2020

Abstract
A simple and fast analytical method is described for the quantitative determination of low levels of paraquat residues in water. The method involves extraction and concentration of paraquat in water by using a C18 Sep-Pak cartridge followed by reverse phase high performance liquid chromatographic determination with ultraviolet detection at 257 nm. Recoveries of paraquat from spiked samples were above 93% with a coefficient of variation of 6.1%. The method can be used for water samples with paraquat concentrations as low as 0.05 ppm.
Simultaneous Determination of Protein (Nitrogen), Phosphorus, and Calcium in Animal Feedstuffs by Multichannel Flow-Injection Analysis
Authors: Staden Jacobus F Van 
Published: February 2020

Abstract
A 3-channel flow-injection procedure was developed, which enables the simultaneous determination of protein, phosphorus, and calcium in a wide range of animal feeds from a single digestion. Samples are digested with a block digestor, diluted, and analyzed at a rate of 82 samples/h. Protein (nitrogen) as ammonia is determined colorimetrically by the indophenol method. Phosphorus and calcium are determined by measuring the absorbances of the molybdenum blue and calcium-cresolphthalein complexes at 660 and 580 nm, respectively. Protein is determined in the range from 0 to 75%, phosphorus in the range from 0 to 6%, and calcium in the range from 0 to 6%. The results obtained do not differ significantly from those obtained by proven manual methods, and considerable time, space, and reagents are saved.
Comparative Analysis of Meat Samples Prepared with Food Chopper and Bowl Cutter
Authors: Pettinati Julio D , Ackerman Stanley A , Jenkins Ronald K , Happich Muriel L , Phillips John G 
Published: February 2020

Abstract
Analyses of meat samples after preparation with either a bowl cutter or by the official procedure with a food chopper were compared for homogeneity of comminution and for differences in fat, moisture, and protein content. Cutting time in the bowl cutter was limited to minimize temperature rise in samples. Beef chuck, pork shoulder, and beef shank, cheek, and tongue were used in the study. Variances of replicate analysis data for the 5 meat types were pooled for either cutter or chopper treatment and for each analyzed component. Sample portions cut and mixed by using the bowl cutter were more homogeneous than those ground with a food chopper. Comparative accuracy was indicated by fat and moisture means: 5 were in good agreement and 5 differed significantly; 3 of 5 paired protein means differed significantly but were within 0.3% protein. Results on precision and accuracy as well as the simplicity and convenience of the bowl cutter procedure favor its use as an alternative to a food chopper for preparing meat samples for analysis.
High Performance Liquid Chromatographic Analysis of Rotenone Formulations: Collaborative Study
Authors: Bushway Rodney J ,   Collaborators:, Bennett M J , Betker W R , Bolduc R , Burns A , Carlstrom A A , Cuan E , Doherty P J , Freedlander R S , Fugere J B , Gentry G M , Hanks A R , Hodgins W E , Jung P D , King W , Launer J E , Meinen V J , Minyard J P , Polli R L , Porterfield D , Schwamb L , Skelly N E , Stringham R W , Wood G A 
Published: February 2020

Abstract
A collaborative study was conducted on a high performance liquid chromatographic (HPLC) method for determining rotenone in formulations. One liquid and 4 dust samples, containing other rotenoids and pesticides, with rotenone guarantees ranging from 0.75% to 20% were analyzed by 16 laboratories. Peak height measurements were used by 14 laboratories while 8 laboratories used integrator area measurements. Samples were extracted on a rotary shaker for 1% h with dioxane. An aliquot was analyzed using reverse phase HPLC and UV detection at 280 nm. Coefficients of variation ranged from 2.47 to 3.19% for peak height determinations and from 2.56 to 6.00% for peak area determinations. One collaborator analyzed the samples by the official infrared method for a comparison. The HPLC method has been adopted official first action.
Multiresidue Method for Determination of Pesticides in Kiwif ruit, Apples, and Berryfruits
Authors: Holland P T , Mcghie T K 
Published: February 2020

Abstract
A rapid multiresidue procedure for fruits, based on methanol extraction, is presented. Water and highly water-soluble co-extractives are removed by partitioning the pesticides into toluene. Carbon-cellulose-Florisil cleanup is performed before gas chromatography on OV-225 with electron capture detection. A wide range of pesticides can be determined to 0.1 mg/kg without concentrating the extract. Gas chromatography of the crude toluene partition using SE-30 and an alkali flame ionization detector provides confirmatory data and allows detection of some carbamates. Dichlorvos, dimethoate, and acephate are determined directly in the methanol extract by flame photometric detection. High recoveries were obtained for 4 organochlorine insecticides, 13 organophosphorus insecticides, 2 synthetic pyrethroids, two JV-methyl carbamates, and 10 fungicides. The method is economical of solvents, glassware, and time, and is recommended for routine surveillance of residue levels on fruit.
High Performance Liquid Chromatographic and Colorimetric Determination of Synthetic Dyes in Gelatin-Containing Sweets, Following Polyamide Adsorption and Ion-Pair Extraction with Tri-n-octylamine
Authors: Puttemans Marc L , Dryon Louis , Massart Désiŕe L 
Published: February 2020

Abstract
Dyes are determined in gelatin-containing sweets. The gelatin must be eliminated first because it interferes with the normal ion-pair extraction of dyes with tri-n-octylamine to chloroform. Techniques such as precipitation of gelatin with organic solvents, and add and enzymatic digestion of gelatin are shown to be unsuccessful because the remaining ;elatin still influences the extraction scheme. Posicive results are obtained when dyes are adsorbed on polyamide, gelatin is washed away, and dyes are desorbed with a methanol-ammonia mixture. Dyes are identified by thin layer chromatography and high performance liquid chromatography (HPLC), and quantitated by HPLC or colorimetry.
Electrothermal Atomic Absorption Spectroscopic Determination of Chromium in Plant Tissues
Authors: Cary Earle E , Rutzke Michael 
Published: February 2020

Abstract
This method involves sample digestion in nitric, perchloric, and sulfuric acids. Chromium is concentrated by coprecipitation with ferric hydroxide. Redissolved iron is removed by liquid-liquid extraction, remaining silica is dissolved with hydrofluoric acid, and chromium is determined by electrothermal atomic absorption spectrometry. The sensitivity and detection limits for chromium approach those given by the manufacturers of the various instruments. Recovery studies and analysis of standard materials show that this method is reliable.
Determination of Lead in Bonemeal by Differential Pulse Anodic Stripping Voltammetry Using a Hydrochloric Acid Solubilization
Authors: Satzger R Duane , Kuennen Roy W , Fricke Fred L 
Published: February 2020

Abstract
A safe, rapid method is described for the determination of lead in bonemeal. This method uses a hydrochloric acid solubilization performed under pressure followed by determination by differential pulse anodic stripping voltammetry. This provides an alternative to a nitric-perchloric acid wet ash. Data obtained using both methods are compared. The mean recovery of a standard Pb spike was 99.2 ± 1%. The concentration of Pb in bonemeal ranged from 1.0 to 15.6 μg/g.
Dilution Errors in Aflatoxin Determinations Caused by Compounds Extracted from Peanuts
Authors: Dickens James W , Whitaker Thomas B 
Published: February 2020

Abstract
Several methods have been developed to analyze peanuts for aflatoxin by using thin layer chromatography (TLC). These methods depend on solvent extraction of aflatoxin from a sample of the product. Unfortunately, solvent solutions used to extract aflatoxin from peanuts also extract measurable quantities of other compounds such as oils, fats, sugars, and protein. The volume of these extracted compounds causes error in measuring the proportion of the solvent solution analyzed for aflatoxin. Also, because the cleanup procedures for some methods are inadequate, the volume of some of these extracted compounds also causes error in measuring the proportion of the extracted aflatoxin placed on TLC plates. These 2 errors cause underestimation of aflatoxin concentrations by approximately 11,14, and 57c for the CB method, the modified version of the BF method generally used for raw peanuts, and a water slurry method, respectively. The correction specified bytheCB method for fats in the extraction solvent reduces the approximate error for the CB method from 11 to 1%.
Determination of Styrene Migration from Food-Contact Polymers into Margarine, Using Azeotropic Distillation and Headspace Gas Chromatography
Authors: Varner Sandra L , Breder Charles V , Fazio Thomas 
Published: February 2020

Abstract
Migration studies were conducted to determine the quantity of styrene that migrates from polymers into fatty foods, specifically margarine. Azeotropic distillation was used to isolate styrene from the margarine. Headspace gas chromatography with a Chromosorb 104 column and a flame ionization detector was used for quantitation. The quantitation limit for the method was about 25 ppb (wt/wt) styrene in margarine. On the average, greater than 90% of the styrene was recovered. Several commercial margarines were examined. The method and results of the migration studies are presented. There was no detectable migration of styrene into margarine.
Application of Tenax Trapping to Analysis of Gas Phase Organic Compounds in Ultra-Low Tar Cigarette Smoke
Authors: Higgins Cecil E , Griest Wayne H , Olerich Gerry 
Published: February 2020

Abstract
A method well suited to the analysis of gas phase organic compounds in ultra-low tar delivery cigarette smoke has been developed. The cigarette is smoked directly through a filter and a Tenax trap arranged in series. The components collected on Tenax are analyzed by thermal-desorption programmed-temperature gas chromatography. Components are then quantitated by the use of external standards. The smoke from high tar delivery cigarettes also can be analyzed by thermal desorption gas chromatography of portions of well mixed solid dilutions of the trapping Tenax. Deliveries of 34 gas phase components were determined for 4 ultra-low tar cigarettes having tar deliveries ranging from &lt;0.01 to 3 mg tar/cigarette, and 24 components for 5 cigarettes delivering 7 to 45 mg tar/cigarette.
Screening of Fresh Water Fish Extracts for Enzyme-Inducing Substances by an Aryl Hydrocarbon Hydroxylase Induction Bioassay Technique
Authors: Casterline James L , Bradlaw June A , Puma Bartholomew J , Ku Yuoh 
Published: February 2020

Abstract
A sensitive biological test to detect the presence of certain contaminants, such as highly toxic halogenated dioxins, dibenzofurans, and biphenyls in foods, was applied to extracts of fresh water fish that had been prepared by a food extraction-cleanup procedure developed by the Food and Drug Administration for pesticides and industrial chemicals. Aryl hydrocarbon hydroxylase (AHH) activity in a rat hepatoma cell line was used as the biological detection system for residues that induce enzyme activity. The induction of AHH activity by the extracts was compared with a standard AHH-induction curve for the most active compound known, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and results were computed as TCDD equivalents. Several dilutions of fish extracts were used to produce AHH-induction curves from which an optimal dose-response range was determined and used to estimate TCDD equivalents. Cleaned-up extracts of fish obtained from different water bodies in the United States were examined for AHH activity. The samples which had low levels of polyhalogenated contaminants produced low biological activity, while a higher activity was obtained from fish that contained higher levels of polyhalogenated contaminants. The results suggest that the fish extracts can be screened for AHH inducers before chemical analysis.
Identification of Trout and Salmon Bloods by Simple Immunological Technique and by Electrofocusing Patterns of Red Cell Enzyme Superoxide Dismutase
Authors: Sutton John G , Goodwin Janet , Horscroft Gillian , Stockdale Russell E , Frake Allan 
Published: February 2020

Abstract
Species identification of animal bloods is readily achieved by immunological tests. Differentiation among fish species on this basis is more difficult although considerable success has been achieved on the basis of both inter- and intra-specific differences in their serum proteins. This report describes a method for the identification of the different species of fish within the Salmonidae family and some coarse fish families on the basis of an immunological test and electrofocusing patterns of the enzyme superoxide dismutase from the red cell. The immunological technique relies on the development of a specific anti-trout (Salmonidae) serum which is used initially to differentiate the blood of a Salmonidae from other freshwater fish. Further discrimination, within the Salmonidae, is made on the basis of the different polymorphic forms of the enzyme superoxide dismutase separated in a pH 2.5 to 8 gradient. Using this technique, it is possible to differentiate among salmon, sea/brown trout, char, cheetah trout, and a number of varieties of rainbow trout.
High Pressure Liquid Chromatographic Determination of Sulfisoxazole in Dosage Forms: Collaborative Study
Authors: Roos Robert W ,   Collaborators:, Alexander L R , Falcone N , Lepore J , Mack G D , Marzilli J , Muzeni R , Papas A N 
Published: February 2020

Abstract
A reverse phase high pressure liquid chromatographic method for the determination of sulfisoxazole in tablets, solution, and ointment dosage forms was collaboratively studied by 7 laboratories. The method uses a C18 column, an acetonitrile-acetic acid-water mobile phase, sulfadimethoxime as the internal standard, and photometric detection at 254 nm. Collaborators were supplied samples of 2 commercial tablets, 1 synthetic tablet powder, 1 commercial and 1 synthetic ophthalmic solution, and 1 commercial ophthalmic ointment. Mean recoveries of sulfisoxazole from the synthetic tablet powder and ophthalmic solution were 99.9 and 100.0%, respectively. Mean coefficients of variation for all samples analyzed were less than 2%. The method was adopted interim official first action.
Comparison of AOAC and Atomic Absorption Spectrophotometry Methods for Determining Sodium in Fertilizers: Collaborative Study
Authors: Corominas Luis F , Navarro Roberto A , Rojas Pedro ,   Collaborators:, Aihara M , Baker N I F , Baumgartner B , Case V W , Cherwin M G , Erickson E , Huber E J , Hunter G B , Jasper D , Johnson F J , Lartigue L , Mobley R J , Navarro R A , Reimann L , Rojas P , Roll E F , Sabapathy T R , Sensmeier R K , Smith J L , Ware W C , Williams J L , Wood T M , Woodis T C 
Published: February 2020

Abstract
A collaborative study was carried out to compare AOAC method 2.147-2.150 for determining sodium in fertilizers with the atomic absorption spectrophotometric (AAS) method. Twelve synthetic NPK samples, 6 pairs of blind duplicates (0.06-8.5% Na), were sent to 22 collaborators; a total of 13 sets of results were received and evaluated by the modified matched pairs technique. The AAS method showed better performance in samples with low sodium content and high potassium content. The AAS method has been adopted official first action for determining sodium in fertilizers.
Survey of Infant Foods for Clostridium botulinum Spores
Authors: Guilfoyle Dennis E , Yager James F 
Published: February 2020

Abstract
A total of 236 samples of infant foods, including honey, dry cereal, nonfat dry milk, evaporated milk, canned formula, and canned baby food, were collected in the New York City area and tested for the presence of Clostridium botulinum spores. Methods for recovery of spores were validated using foods spiked with 4 spores/mL or g. None of the products contained C. botulinum spores, indicating that their incidence in these commercial foods is not widespread. This limited study did not identify any food types that could be suspected of being involved in the transmission of infant botulism.
Ion-Pair Reverse Phase Liquid Chromatographic Determination of Sodium Acifluorfen in Feed
Authors: Roy Timothy A , Meeks J Ralph , Mackerer Carl R 
Published: February 2020

Abstract
Ion-pair reverse phase liquid chromatography (LC) and UV detection at 280 nm have been used to determine sodium acifluorfen (sodium-5-[2-chloro- 4-(trifluoromethyl)-phenoxy]-2-nitrobenzoate), an experimental diphenyl ether herbicide, in dog feed. Sodium-5-(2,4-dichlorophenoxy)-2-nitrobenzoate is used as the internal standard. The feed is homogenized in 0.01N HC1, followed by ethyl acetate extraction, and centrifugation. The organic layer is removed and evaporated and the residue is reconstituted in methanol and filtered before LC analysis (mobile phase methanol-water (58 + 42), 0.005M in letrabutylammonium phosphate and 0.045M in (NH4)2HPO4, at pH 7.4). The ion-pair technique offers a high degree of control over the retention characteristics of the herbicide and internal standard. The use of the internal standard permits precise and accurate quantitation and substantially reduces analysis time compared with the external standard method.
Comparison of Gas Chromatographic/Mass Spectrometric and Liquid Chromatographic/Mass Spectrometric Methods for Confirmation of Coumaphos and Its Oxygen Analog in Eggs and Milk
Authors: White Kevin D , Min Zhao , Brumley William C , Krause Richard T , Sphon James A 
Published: February 2020

Abstract
A comparison of a liquid chromatographic (LC)/mass spectrometric (MS) procedure for confirming coumaphos, an organophosphate insecticide, and its oxygen analog in milk and eggs with a capillary gas chromatographic (GO/MS method is presented. For the confirmation of coumaphos and its oxygen analog, multiple ion detection of both positive and negative ions from the chemical ionization mass spectra was used. Samples of milk and eggs fortified with the 2 compounds at the 0.1,0.01, and 0.005 ppm levels were analyzed. The major finding is the relatively greater efficiency of the LC/MS interface compared with the GC/MS capillary injector.
Liquid Chromatography, Microfluorometry, and Dye-Titration Determination of Vitamin C in Fresh Fruit and Vegetables
Authors: Wills Ron B H , Wimalasirl Pushparany , Greenfield Heather 
Published: February 2020

Abstract
The vitamin C content of several fresh fruit and vegetables was determined by a liquid chromatographic (LC) method which gave simultaneous separate values for ascorbic acid and dehydroascorbic acid (DHA) and by the official AOAC methods of microfluorometry and dye-titration. The levels of ascorbic acid obtained by LC and dye-titration were in good agreement, except for a few colored products where it was difficult to determine the end point of the titration. The combined values for ascorbic acid and DHA obtained by LC and microfluorometry were in agreement for most produce, but for about one-third of the samples, the values obtained by microfluorometry were significantly higher.
Liquid Chromatographic Assay for Dalapon Grasskiller Products: Collaborative Study
Authors: Stevens Timothy S , Wedelstaedt Cathy ,   Collaborators:, Bennett B , Grorud R , Harris T , Hodgins E , King S W , Lonn P D 
Published: February 2020

Abstract
As a replacement for the present mercury reagent titration assay for dalapon grasskiller products, a liquid chromatographic method has been developed and collaboratively studied. The method separates the active ingredient, 2,2-dichloropropionic acid, from its related products by paired ion chromatography with UV detection at 214 nm. Statistical analysis of the data indicates that a single assay from one laboratory should not differ by more than 2.2% from the average assay of many laboratories, at the 95% confidence level, for products containing about 75% 2,2-dichloropropionic acid equivalent as the magnesium and/or sodium salt. The method has been adopted official first action.
Determination of Authenticity of Sake by Carbon Isotope Ratio Analysis
Authors: Martin Glenn E , Burggraff James M , Alfonso Felipe C , Figert Donald M 
Published: February 2020

Abstract
Sake samples are fractionally distilled so that the resultant ethanol concentration of the distillate is approximately 95%. Determination of 14C by liquid scintillation counting on the ethanol fraction differentiates alcohol produced by fermentation from synthetic ethanol produced from fossil fuel sources. 13C/12C stable isotope ratio analysis (SIRA) is capable of detecting alcohol from a cane or corn source in sake samples. This analysis also shows the addition of corn or cane sugar before or after fermentation of the sake.
Rapid Direct Determination of Lead in Evaporated Milk by Anodic Stripping Voltammetry Without Sample Pretreatment
Authors: Zink Eric W , Moffitt Robert A , Matson Wayne R 
Published: February 2020

Abstract
The method presented describes the direct determination of lead in evaporated milk in which the milk ashing step prior to analysis is eliminated. Digital instrument readout units are μg Pb /mL milk. Total analysis time after instrument calibration is less than 3 min per sample. Range of the method is 0.05-1.0 ppm lead in milk, and precision of the method expressed by relative standard deviation of duplicate pairs ranged from 30% at 0.1 μg/mL to 3% at 1.0 μg/mL of lead in milk. The method compares favorably with the AOAC official first action anodic stripping voltammetric method (25.074). In addition, the method appears to work equally well for skim evaporated milk, sweetened condensed milk, and nonfat powdered dry milk when the latter two are reconstituted with water according to product label instructions. Recovery and interference studies are presented.