bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Cyanogenic Glycoside in Seeds by Molecular Absorption Spectrometry in the Gas Phase
Authors: Kupchella Lawrence , Syty Augusta 
Published: February 2020

Abstract
As a means of evaluating cyanogenic glycoside content, cyanide was determined in apple, cherry, almond, and peach seeds. Sample preparation involved enzymatic hydrolysis and collection of hydrogen cyanide in strong base. For analysis, cyanide was converted to ammonium by addition of excess KMn04 followed by treatment with H2S04, and the resulting NH4+ was determined by the novel gas-phase molecular absorption spectrometric technique. An atomic absorption spectrophotometer, with a flow-through absorption cell replacing the flame, was used in the analysis. Recovery of amygdalin was 98.4 ± 1.2% complete. Cyanogenic glycoside contents determined in seeds (0.93% for apple, 2.05% for cherry, 2.43% for peach, and 0.00% for almond, reported in terms of amygdalin), were confirmed by a standard titration method. The lowest detectable concentration was 0.2 μg NH4+/mL, which corresponds to a detection limit of 0.5 mg amygdalin in the seed sample.
Analyst Performance with Aflatoxin Methods as Determined from AOCS Smalley Check Sample Program: Short-Term and Long-Term Views
Authors: Mckinney John D 
Published: February 2020

Abstract
The International Smalley Aflatoxin Check Sample Program of the American Oil Chemists' Society has offered check sample series for aflatoxins in peanut meal, cottonseed meal, and corn meal since 1976, and an aflatoxin M in raw milk series since 1980. This paper provides the computed mean of all analysts' results and between-laboratory precision for each of the samples in each of the check sample series distributed in 1980–81 and 1981–82. In addition, a comparison is made of the relative measurement and analytical accuracy of those analysts who have participated in the peanut meal series for at least 4 years and in the cottonseed and corn meal series since their inception (6 years). For this comparison, each analyst's result for each sample was calculated as a percent of the mean for all analysts for that sample; these values were then averaged for each analyst over all the meal samples in all the series for each meal type in which the analyst had participated, to obtain an overall measure of analytical accuracy. A similar calculation was made using the reported results for the defined solution of anatoxins included in each series, to obtain an overall measure of measurement accuracy. An evaluation of the meal series results for the past 2 seasons shows an overall within-laboratory precision in the range reported for the collaborative studies by which the methods were validated; the between-laboratory precision, although improved over past years, is still far from the collaborative study range. The precision data for the aflatoxin solution included in each series indicate this bias could be related, in large part, to the reference standards used. The extended period evaluation of analysts' performance shows no apparent correlation between measurement and analytical accuracy except for a general positive trend for those analysts using the BF method for anatoxins in peanut meal. A comparison of the accuracy of the BF and CB methods for aflatoxins in peanut meal shows no significant difference between results by the 2 methods on the basis of the extended period evaluation, in contrast to the generally higher results for the CB method in the past 2 seasons' evaluation. The scatter in the average analysts' analytical accuracy is essentially the same, regardless of the method used.
Preparation of Deoxynivalenol (Vomitoxin) from Field-Inoculated Corn
Authors: Scott Peter M , Lawrence Guillaume A , Telli Arvind , Iyengar Jagannath R 
Published: February 2020

Abstract
A process was developed for production of gram quantities of deoxynivalenol (DON) from corn that had been inoculated in the field with Fusarium graminearum and was estimated to contain 400–500 mg DON/kg. Steps in the purification procedure included extraction with methanol–water (1 + 1), partition from an aqueous solution into ethyl acetate by using a hydrophilic matrix, defatting, Florisil column chromatography, methylene chloride-water partition, semipreparative liquid chromatography (LC), and crystallization from ethyl acetate. The average yield of crystalline DON produced by this method (or with minor variations) was 281 mg/kg.
Comparison of Three Methods for Determination of N-NitrosopyrroIidine in Fried Dry-Cured Bacon
Authors: Gates Robert A , Pensabene John W , Walter Fiddler 
Published: February 2020

Abstract
The recently developed Eastern Regional Research Center (ERRC) dry column chromatographic procedure for determining A'-nitrosopyrrolidine (NPYR) in fried cure-pumped bacon was evaluated for its applicability to fried dry-cured bacon. The method was then compared with 2 established procedures for volatile nitrosamine analysis in cured meat products: the multidetection thermal energy analyzer (MD) method and the mineral oil distillation (MOD) screening procedure. No significant difference (P &lt; 0.05) in NPYR values was found between the ERRC and MD procedures, but significant differences were found between the ERRC and MOD procedures and between the MOD and MD procedures. No artifactual nitrosamine formation was found in the ERRC procedure, but significant amounts were found in samples analyzed by the MOD procedure. The ERRC method was demonstrated to be rugged and very rapid. It is proposed that the ERRC method replace the MOD method as the official screening procedure for NPYR in fried bacon.
Titrimetric Determination of Ascorbic Acid Using Chloranil
Authors: Verma Krishna K , Jain Archana , Rawat Rameshwar 
Published: February 2020

Abstract
Ascorbic acid is oxidized and quantitatively titrated with chloranil (2,3,5,6-tetrachloro-l,4-benzoquinone) in the presence of hexamethylenetetramine in acetone-water; the end point is determined visually by the appearance of a golden yellow color. Colored solutions are assayed by setting the initial absorbance at 451 nm to zero or the minimum, titrating with chloranil solution, and measuring absorbance after each increment of titrant. A plot of the volume of chloranil added against the absorbance gives a straight line with the volume intercept as the end point. Interference by the thiol group of cysteine, glutathione, etc., is avoided by masking with acrylamide; interference by iron(II) is masked with ammonium thiocyanate and sodium potassium tartrate. Hydrogen sulfite and thiourea (which do not interfere) are added as antioxidants during extraction of ascorbic acid from drugs and fruits.
Liquid Chromatographic and Ultraviolet Spectrophotometric Determination of Bevantolol and Hydrochlorothiazide in Feeds
Authors: Spurlock Carola H , Schneider Horst G 
Published: February 2020

Abstract
Separate assay methods have been developed for the 2 components of an SO + 20 drug blend of bevantolol and hydrochlorothiazide (HCT) in admixtures with animal feed. Drug/diet admixtures are extracted with methanol for reverse phase ion-pair liquid chromatographic (LC) assay of bevantolol, and with acetonitrile for ultraviolet spectrophotometric assay of HCT. Bevantolol, a cardioselective beta blocker, is separated from soluble feed components with an RP-18 column, using methanol–water–acetic acid (60 + 40 + 1) containing 0.005M octanesulfonic acid, sodium salt, as ion-pairing reagent. HCT is determined spectrophotometrically in acetonitrile extracts, using a suitable blank extract as reference. Average recovery of HCT from an admixture of 0.5 mg blend/g diet is 94.5% ± 4.3 RSD and at 2.0 mg/g, 101.5% ± 3.5 RSD. Bevantolol recovery from the same admixtures is 101.8% ± 2.7 RSD and 99.0% ± 3.5 RSD, respectively, using the method as described.
Modification of Liquid Chromatographic Method for Analysis of Rotenone Formulations
Authors: Bushway Rodney J 
Published: February 2020

Abstract
Modifications have been made on the official first action liquid chromatographic method for analysis of rotenone formulations. Methanol–water was replaced with acetonitrile–water as the eluant and methanol was substituted for dioxane as the extracting solvent. The extraction procedure has been changed from 1½ h of rotary shaking to 5 min of sonication. The rest of the procedure is identical to the published method. For 9 different products analyzed 6 times each, the percent coefficients of variation were all below 2.40. Five of these 9 samples were previously used in the rotenone collaborative study. A comparison of results from both studies showed that the modifications did not affect the percent rotenone found. It is recommended that these changes be tested in a mini-collaborative study.
Near Infrared Reflectance Spectroscopic Determination of Protein Nitrogen in Plant Tissue
Authors: Isaac Robert A , Johnson William C 
Published: February 2020

Abstract
A rapid, nondestructive method is described for the determination of protein nitrogen in plant tissue, using near infrared reflectance (NIR) spectroscopy. Procedures for instrument calibration are discussed. Comparisons between Kjeldahl nitrogen and NIR nitrogen are made for corn leaf tissue from Georgia and Indiana. Multiple correlation coefficients for other plant tissues such as peanuts, soybean, wheat, pecan, bermuda grass, and bent grass are also shown.
Liquid Chromatographic Determination of Aspartame in Dry Beverage Bases and Sweetener Tablets with Confirmation by Thin Layer Chromatography
Authors: Daniels Daniel H , Joe Frank L , Warner Charles R , Fazio Thomas 
Published: February 2020

Abstract
A liquid chromatographic method is described for the determination of aspartame in dry beverage bases and sweetener tablets. The sample was mixed with the mobile phase, the pH was adjusted to within ±0.1 pH unit of the mobile phase, and the sample was diluted to volume with the mobile phase. The solution was Altered and a 10 μL aliquot was injected onto a C18 reverse phase column. Aspartame was quantitated with an ultraviolet detector. Recoveries of aspartame ranged from 94 to 111%. The dry beverage bases contained 5–13% aspartame and the sweetener tablets contained 19% aspartame. The presence of aspartame was confirmed by using thin layer chromatography.
Determination of Residual Levels and Migration of Benzene from Styrene-Containing Polymers
Authors: Varner Sandra L 
Published: February 2020

Abstract
Styrene-based food-contact polymers were examined for the presence and migration of residual benzene. Headspace gas chromatography (GC) with a column of 20% SP 2100–0.1% Carbowax 1500 on Supelcoport and a flame ionization detector were used for quantitation. To determine residual levels, the polymer was dissolved in dimethyl acetamide (DMAC)–water (99 + 1). On the average, &gt;85% of the benzene was recovered. The quantitative determinative limit for the analysis was ca 200 ppb on a polymer basis. Migration tests simulating hot-filling or pasteurization above 150°F (66°C) were undertaken, using water as the food-simulating solvent. A lower limit of ca 0.35 ppb benzene could be quantitated. Several commercial products were examined, including samples of foam, impact, and crystal polystyrene. The levels of benzene found ranged from none to 3.47 ppm. The presence of benzene was confirmed by GC–mass spectrometry.
Comparison of Chemiluminescent and AOAC Methods for Determining Nitrite in Commercial Cured Meat Products
Authors: Fiddler Walter , Doerr Robert C , Gates Robert A , Fox Jay B 
Published: February 2020

Abstract
A chemiluminescent detector was used to measure nitrite in a variety of commercial cured meat products, using the AOAC sample preparation procedure, 24.041. A comparison of the NaNO2 values obtained by using sulfanilamide/N-(1-naphthyl)ethylenediamine (SAN/NED) reagent, sulfanilamide/1-naphthylamine reagent, and chemiluminescent detection (CLD) revealed no significant differences between the latter 2 detection methods. The AOAC SAN/NED reagent combination gave an average of 24.6% lower NaNO2 results than CLD. Examination of the sample preparation extraction and heating steps indicated that the procedure could not be made more rapid because of the need to destroy residual reductants and release “bound-complexed-reacted” nitrite from the meat samples.
Spectrophotometric Determination of Bromhexine Hydrochloride in Pharmaceutical Preparations
Authors: Santoro Maria Inês R M , Dos Santos Mirza M , Magalhães João F 
Published: February 2020

Abstract
The presence of an aromatic primary amino group in bromhexine HCI enables the use of diazotization-coupling, according to the classic Bratton-Marshall method, for its analysis in pharmaceutical preparations. Spectrophotometric parameters were established for standardization of the method, including statistical analysis of data. Substances such as potassium guaiacolsulfonate, ampicillin, cephalexin, oxytetracycline HCI, amoxycillin, and erythromycin ethylsuccinate do not interfere with the determination. The precision of the method is about 2.0%.
Verification of Authenticity of Orange Juice
Authors: Brause Allan R , Raterman Joseph M , Petrus Donald R , Doner Landis W 
Published: February 2020

Abstract
A series of instrumental analyses is used for verification of the authenticity of orange juice: liquid chromatography for sugars, UV-visible spectrophotometry for absorbance measurements, stable isotope ratio analysis of δ13C and δ18O values, and atomic absorption spectrophotometry for potassium and sodium analyses. All authentic orange juices possess positive δ18O values, while those of ground water and water in beet invert syrups are negative. Hence, addition of either to orange juices decreases δ18O values, and allows detection of nonauthentic products.
Gas Chromatographic Analysis of Coyote and Magpie Tissues for Residues of Compound 1080 (Sodium Fluoroacetate)
Authors: Okuno Iwao , Connolly Guy E , Savarie Peter J , Breidenstein Charles P 
Published: February 2020

Abstract
Tissues of coyotes and magpies administered known dosages of 1080 were analyzed for residues by an analytical method specifying gas chromatography and electron capture detection. The repeatability of the method was determined for the replicate analyses of coyote muscle tissue samples aged under different storage conditions. The average coefficient of variation (CV) was 6% for quadruplicate determinations of 1080 in fresh tissues, 12–14% for samples stored at – 10°C for 30–60 days, and 24 % for samples aged for 7 days at ambient temperatures. The larger CV value obtained for stored samples is attributed more to greater sample variability than to less precision of the analytical method. Residues of 1080 appear to be relatively stable in tissues; there was essentially no change in the concentration of 1080 in samples stored up to 28 days at ambient temperature. Residue levels in the muscle, heart, kidney, and intestine were comparable, slightly lower in the liver, and much higher in the stomach. The concentration of 1080 in the muscle tissue was related to the administered dosages. Correlation analyses of dosages and residue levels in coyote muscle tissue showed a correlation coefficient of 0.99 for 1080 administered by gavage, and 0.88 for 1080 administered by bait. A correlation coefficient of 0.99 was observed between dosages and mean residues in the breast muscle tissues of magpies. The average CV value was 3.5% for duplicate analyses of 1 g samples of magpie tissues.
Pad-Plate Diffusion Assay for Virginiamycin in Mash-Type Feeds
Authors: Katz Stanley E , Katz Jack M , Miller James A , Wang Richard , Shapiro Ralph 
Published: February 2020

Abstract
An assay procedure has been developed for virginiamycin in mash-type feeds which includes removing fat interferences from the feeds by a rapid petroleum ether wash, a citric acid extraction, an acetone extraction, and the use of the pad-plate diffusion system. The procedure eliminates the need for compensatory curves prepared from feeds of the same or similar composition. Recoveries from 10 laboratory-prepared feeds containing 11.0 μg virginiamycin/g averaged 89.3% with a coefficient of variation (CV) of 5.76%. Recoveries from a laboratory-prepared feed containing 13.2 μg virginiamycin/g averaged 89.9% (CV 9.92%). The procedure is simple, reasonably accurate, and precise.
Rapid Assay for Tetracycline in Premixes and Mixed Feeds
Authors: Katz Jack M , Katz Stanley E 
Published: February 2020

Abstract
A rapid assay for tetracyclines in premixes and mixed feeds is described, which uses the extraction and dilution systems of AOAC methods, and a strain of Bacillus stearothermophilus ATCC 12980 selected to grow at 40°C. The incubation period is 4.5 h. The rapid assay yields results similar to those obtained using the AOAC methods. For a 50 g chlortetracycline (CTC)/lb commercial premix, the rapid procedure averaged 109.2% of label vs 104.4% obtained using the AOAC method; for a 20 g CTC/lb premix, the rapid procedure averaged 89.2% vs 89.3% obtained with the AOAC method. In 2 commercial premixes containing 50 g oxytetracycline/lb, the rapid assay averaged 127.1 and 110.5% vs 134.7 and 113.5% obtained using the AOAC method. In feed extracts supplemented with CTC equivalent to 25–200 g/ton, rapid assay recoveries averaged 101.9%; recoveries using the AOAC method averaged 110.6%. For feed extracts supplemented with oxytetracycline at the same levels, recoveries by the rapid assay averaged 95.4%, and by the AOAC method, 106.0%.
Ion-Pair Extraction Cleanup for Liquid Chromatographic Determination of Bentazon in Crops and Soil
Authors: Åkerblom Malin , Alex Gunborg 
Published: February 2020

Abstract
Bentazon was selectively extracted as an ion pair with tetrabutylammonium ion into dichloromethane. This technique was used to clean up crop and soil samples before determination of bentazon by reverse phase liquid chromatography and UV detection. Recoveries from potatoes, cucumbers, wheat grain, and clay soil were 77–103%, with a detection limit of 0.02 mg/kg.
Rapid Differential Pulse Polarographic Determination of Tiaprofenic Acid
Authors: Mohamed Mohamed E , Wahbi Abdel-Aziz M , Gad-Kariem EL Rasheed A , Hassan Mahmoud M A 
Published: February 2020

Abstract
Tiaprofenic acid (Surgam®) has been determined directly by using differential pulse polarography (DPP) and pH 5.5 acetate buffer as a supporting electrolyte. The differential pulse polarogram was obtained under constant amplitude pulses of 50 mV superimposed on a linearly increasing dc ramp. Peak current was measured at the peak potential of — 0.990 V vs Ag/AgCl reference electrode. Under the experimental conditions used, a linear relationship between peak current and concentration was established over the range 0.5-5.0 ng/mL. Mean percentage recoveries for tiaprofenic acid in authentic and tablet forms were 100.27 ± 2.25 and 99.45 ± 1.44, respectively. The results obtained by the DPP method were compared with those of the spectrophotometric method used by the manufacturer for the analysis of tiaprofenic acid and its tablet form.
Nonaqueous Reverse Phase Liquid Chromatographic Analysis for Cholesterol in Milk Chocolate
Authors: Hurst W Jeffrey , Aleo Michael D , Martin Robert A 
Published: February 2020

Abstract
A method using liquid chromatography was developed for the analysis of cholesterol in milk chocolate products. The method involves saponification of the sample with methanolic KOH followed by extraction with ether. Potentially interfering components are eliminated through the use of a silica Sep-Pak cleanup step before injection. The nonaqueous reverse phase LC system consists of a C18 column and an isopropanol- hexane mobile phase with direct detection at 205 nm. Recoveries of 1, 3, and 5 mg cholesterol added to 1 g sample of milk chocolate were 88.6, 102.8, and 110.1%, respectively. Studies conducted with [4-14C]-cholesterol were undertaken to further document the accuracy of the method.
Evaluation of Electron Capture Gas Chromatographic Method for Determination of Methyl Mercury in Freezer-Case Seafoods
Authors: Alvarez George H , Hight George H , Capar Stephen G 
Published: February 2020

Abstract
A method was recently adopted by AOAC for determination of methylbound mercury in canned and fresh-frozen seafood by electron capture gas chromatography. That method was applied to the analysis of commercially prepared freezer-case seafoods. None of the commercially added ingredients produced electron capture responses that interfered in the analysis for methyl mercury. Recoveries of 95.7-114% were obtained in fortification studies of methyl mercury at 0.2 and 1.0 ppm levels. The applicability of aqueous methyl mercuric chloride solution for fortification studies was demonstrated.
SIMCA (Soft Independent Modeling of Class Analogy) Demonstrated with Characterization and Classification of Italian Olive Oil
Authors: Marie-Paule Derde , Danny Coomans , Désiré L Massart 
Published: February 2020

Abstract
The multivariate technique SIMCA (soft independent modeling of class analogy) has been applied to the classification of foodstuffs on the basis of gas chromatographic profiles of some of their constituents. The data set used in this investigation consists of the percentage distribution of 7 fatty acids (7 variables) in 100 samples of virgin olive oil from 2 different regions (2 classes) of Italy, East and West Liguria. The SIMCA method can be used to compute whether an olive oil sample from Liguria originated in the western or eastern part of this region, while 98.8% of samples that do not originate in Liguria are correctly classified as outliers. The developed classification rules are adequate for identifying oils according to their origin. Standard decision diagrams (SDD) are very attractive tools for classification of new samples; the similarity between a new sample and each of the classes is easily computed. Consequently, the SDD visualizes any similarity toward each of the classes, and enables a decision on whether the new sample originates in one of the regions under study.
Gas Chromatographic Determination of Deoxynivalenol in Wheat with Electron Capture Detection
Authors: Ware George M , Carman Allen , Francis Octave , Kuan Shia 
Published: February 2020

Abstract
A method is described for the determination of deoxynivalenol (DON) in wheat. The method involves sample extraction with chloroformethanol (8 + 2), column chromatographic cleanup on silica gel of small particle size, and derivatization with heptafluorobutyric acid anhydride using 4-dimethyIaminopyridine as a catalyst. The derivative DON trisheptafluorobutyrate is determined by gas chromatography using an electron capture detector. Recoveries of DON added to wheat at levels of 118—1184 ng/g averaged 88% with a coefficient of variation of 8.6%.
Identification of Aflatoxins by Quadrupole Mass Spectrometry/Mass Spectrometry
Authors: Plattner Ronald D , Bennett Glenn A , Stubblefield Robert D 
Published: February 2020

Abstract
MS/MS daughter experiments were recorded for aflatoxins B1, B2, G1, G2, M1, M2, and aflatoxicol, using 3 ionization modes. Daughters were recorded from the molecular ion (M+) using electron impact ionization (EI). Daughters from the protonated molecules (MH+) were recorded in the positive ion mode and the daughters from the molecular anion (M+) were recorded in the negative ion mode using chemical ionization (CI). These daughter spectra are all relatively simple. The EI daughters are quite similar to conventional EI spectra. The yield of (M-) is about 100 times greater than the yield of M+ in EI or MH+ in isobutane CI spectrum. Negative ion daughter spectra were used to demonstrate the feasibility of determining the presence of aflatoxin B1 in crude extracts of contaminated corn. Aflatoxin B1 could be detected at 10 ppb.