bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enumeration of Probiotic Bacilli Spores in Animal Feed: Interlaboratory Study
Authors: Leuschner Renata G K , Bew Jan , Cruz Armando ,   Collaborators:, Adler A , Auclair E , Bertin G , Braconnier M , Domig K , Jones P , Kneifel W , Krause M , Marmo S , Michard J , Mietke H , O’Briain A , Olofson A S , Ruppitsch W , Thalmann A , Voets A , Warmerdam C 
Published: July 2020

Abstract
Fourteen out of 17 laboratories completed an interlaboratory study comparing 2 pretreatment protocols of feed samples containing authorized probiotic bacilli spores. Both methods used tryptone soy agar for enumeration. Pretreatment A involved preparation of a suspension of the feed sample in 50% ethanol. For pretreatment B, the sample was suspended in peptone salt solution and heated at 80°C for 10 min. Each laboratory analyzed 12 samples (6 per pretreatment), which represented duplicates of a high (109 colony-forming units [CFU]/g) and low (105 CFU/g) level of bacilli spores or a blank that contained vegetative probiotic bacteria only. For pretreatment A, the re-peatability relative standard deviation (RSDr) was 2.9% for the low level and 2.5% for the high. The reproducibility relative standard deviation (RSDR) values were 7.8 and 5.9%, respectively. Pretreatment B revealed RSDr values of 1.1 and 1.0%, and RSDR values of 5.8 and 3.4%, respectively. The heat treatment (pretreatment B) of feed samples had better precision data, resulted in higher viable bacilli counts, and was more effective in deactivating vegetative background flora. It is therefore recommended for adoption for official control purposes and for CEN and ISO standards.
Multiresidue Method for the Determination of Pesticides in Korean Domestic Crops by Gas Chromatography/Mass Selective Detection
Authors: Chun Ock Kyoung , Kang Hee Gon , Kim Myung Hee 
Published: July 2020

Abstract
The multiresidue method used in this study allows the determination of 101 pesticides, including organophosphorus, organochlorine, and nitrogen-containing pesticides, in crops by gas chromatography with mass selective detector. Analysis was performed in the selected–ion monitoring mode, and the identities of the positive analytes were confirmed by retention time and the ratios of selected ions. The selected ion mode demonstrated an acceptable selectivity for most of the pesticides determined in 3 kinds of samples (Chrysanthemum coronarium; Perilla japonica, leaf; and Lactuca savita, which are very popular vegetables eaten raw in Korea), and very minor interferences were observed in the elution area of the pesticide analytes. Samples were spiked with pesticides at 0.1–1.0 mg/kg. The recoveries of 90% of the pesticides were between 70 and 110%; however, the recoveries of acephate and folpet were very poor, i.e., &lt;50%. The limits of detection (LODs) for most pesticides were between 0.02 and 0.3 mg/kg, and the LODs for about half of the pesticeds studied were &lt;0.05 mg/kg.
Determination of Ginsenosides (Ginseng Saponins) in Dry Root Powder from Panax ginseng, Panax quinquefolius, and Selected Commercial Products by Liquid Chromatography: Interlaboratory Study
Authors: Asafu-Adjaye Ebenezer B , Wong Siu Kay ,   Collaborators:, Arnason J , Betz J , Breakell K , Chen J X , Fitzloff J , Fong H H S , Kim C S , Kwan S Y , Leung H W , Li G Q , Lin R C , Luo G A , Nicolidakis H , Park H , Suen E , Wang X R , Wang Z T , Wen K C , Yeung H W 
Published: July 2020

Abstract
Twelve collaborating laboratories assayed 4 products, namely, Panax ginseng, Panax quinquefolius, and 2 ginseng products, for 6 ginsenosides: Rb1, Rb2, Rc, Rd, Re, andRg1. Collaborators also received a negative control for the recovery study. Pure ginsenosides were provided as reference standards for the liquid chromatography (LC) analysis and the system suitability tests. The LC analyses were performed on the methanol extract using UV detection at 203 nm. For P. ginseng, individual ginsenosides were consistent in their means; repeatability standard deviations (RSDr)rangedfrom4.17to5.09% and reproducibility standard deviations (RSDR) ranged from 7.27 to 11.3%. For P. quinquefolius, the Rb1 and Rb2 ginsenosides were higher and lower in concentration than P. ginseng, with RSDr values of 3.44 and 6.60% and RSDR values of 5.91 and 12.6% respectively, and other analytes at intermediate precisions. For ginseng commercial products, RSDr values ranged from 3.39 to 8.12%, andRSDR values ranged from 7.65 to 16.5%. A recovery study was also conducted for 3 ginsenosides: Rg1, Re, andRb1. The average recoveries were 99.9, 96.2, and 92.3%, respectively. The method is not applicable for the determination of Rg1 and Re in ginseng product at levels &lt;300 mg/kg.
Determination of Nitrogen- and Phosphorus-Containing Pesticide Residues in Vegetables by Gas Chromatography with Nitrogen–Phosphorus and Flame Photometric Detection after Gel Permeation Chromatography and a Two-Step Minicolumn Cleanup
Authors: Ueno Eiji , Oshima Harumi , Saito Isao , Matsumoto Hiroshi 
Published: July 2020

Abstract
An efficient and reliable multiresidue method for determining pesticide residues in a large number of vegetable samples was studied. First, the important target compounds for monitoring, 52 nitrogen-and/or phosphorus-containing pesticides, were selected. The sample was extracted with acetonitrile, and the separated acetonitrile layer was cleaned up by a salting-out step. The acetonitrile extract was purified by gel permeation chromatography that divided the pesticide eluate into 2 fractions; the pesticide fractions were respectively purified by a 2-step minicolumn cleanup in which the second pesticide fraction was loaded on a silica-gel minicolumn. After a Florisil minicolumn was inserted on the silicagel minicolumn, the first pesticide fraction was loaded on the tandem minicolumn, which was eluted with acetone–petroleum ether (3 + 7). The combined eluate was subjected to dual-column gas chromatography (GC) with nitrogen–phosphorus and flame photometric detection. By application of the optimum cleanup conditions to the 52 pesticides selected, good resolution and low breakdown levels of the pesticides during GC were maintained. Recoveries of the 52 pesticides from fortified cabbage, lettuce, spring onion, and spinach ranged from 72 to 108% with relative standard deviations of 2–17%, except for the recoveries of methamidophos and chlorothalonil. The detection limits of the pesticides were satisfactory (0.001–0.009 mg/kg) for monitoring pesticide residues in vegetables.
Application of Derivative Spectrophotometry to Simultaneous Determination of Indomethacin and 5-Methoxy-2-methyl-3-indoleacetic Acid in Metindol Injections
Authors: Stolarczyk Mariusz , Krzek Jan , Rzeszutko Włodzimierz 
Published: July 2020

Abstract
Derivative spectrophotometry was employed to develop a rapid and accurate method for simultaneous determination of indomethacin and 5-methoxy-2-methyl-3-indoleacetic acid as its possible impurity in Metindol injections. At the selected wavelengths, 233.04 and 284.65 nm, no interference between the components determined was observed. Under the established experimental conditions, recoveries of the particular components were from 96.14 to 98.17%. Linearity was maintained over a broad range of concentrations, from 11.88 × 10−3 to 35.64 × 10−3 mg/mL for indomethacin and 0.4 to 1.2 mg/mL for 5-methoxy-2-methyl-3-indoleacetic acid. The limit of detection was found to be 6.0 × 10−3 mg/mL for indomethacin and 0.04 × 10−3 mg/mL for 5-methoxy-2-methyl-3-indoleacetic acid. The limits of quantitation were found to be 10.0 × 10−3 mg/mL and 0.20 × 10−3 mg/mL, respectively.
Multiresidue Analysis of Pesticides in Vegetables and Fruits by Gas Chromatography/Mass Spectrometry after Gel Permeation Chromatography and Graphitized Carbon Column Cleanup
Authors: Ueno Eiji , Oshima Harumi , Saito Isao , Matsumoto Hiroshi , Yoshimura Yoshihiro , Nakazawa Hiroyuki 
Published: July 2020

Abstract
A multiresidue method for pesticides that enables quantitative, sequential analysis of a large number of vegetable and fruit samples by gas chromatography/mass spectrometry has been developed. First, 89 important target compounds were selected for monitoring, and then the appropriate internal standards for these pesticides, 14 stable isotopically labeled pesticides (surrogates), were used. The sample was extracted with acetonitrile, and the extract was cleaned up by a salting-out step followed by redissolution in ethyl acetate. Coextractives were removed automatically by gel permeation chromatography with a graphitized carbon column, and then by use of a tandem silica-gel/PSA cartridge column. Recoveries of 82 of the 89 pesticides from fortified spinach, tomato, apple, and strawberry were within a range from 70 to 120%, and the relative standard deviation values of 80 of the 89 pesticides were &lt;5%. The method was applied to 188 commercial vegetable and fruit samples to demonstrate its use in routine analysis.
One Internal Standard for Multiple Analytes: A Limit and Solution
Authors: Huang Li , Wu Mary 
Published: July 2020

Abstract
The use of a single internal standard (ephedrine-d5) as the basis for calculations of the concentrations of both the major and the minor alkaloids leads to incorrect results from variabilities in the solid-phase extraction (SPE) of the ephedra alkaloids. Because the SPE column is overloaded by ephedrine, the recovery of the internal standard, which is dependent on the dilution factor, is decreased. On the other hand, the recoveries of the minor alkaloids (methylephedrine, methylpseudoephedrine, norephedrine, and norpseudoephedrine) stay high because these compounds are less concentrated and do not overload the SPE column. Consequently, the recovery factors for the major and minor alkaloids are different, or the results are incorrect if the same recovery factor is used.
Thin-Layer Chromatography-Densitometry and Liquid Chromatography Analysis of Alkaloids in Leaves of Papaver somniferum Under Stress Conditions
Authors: Szabó Beata , Lakatos Ágnes , Kõszegi Tamás , Kátay György , Botz L 
Published: July 2020

Abstract
The effect of stress conditions on the concentrations of secondary metabolites were examined during various developmental stages of Papaver somniferum plants. P. somniferum plants were grown in laboratory conditions (Budakalász). The experiment consisted of 22 treatments. Significantly different alkaloid contents can be observed under different stress conditions. In general, the alkaloid contents of plants are very low; therefore, a highly sensitive and reliable method has to be developed for analysis. The amount of alkaloids was measured by 2 separation and detection techniques. Accuracy of the thin-layer chromatography method for quantitative analysis is limited. Without purification of samples the background is too noisy. Column liquid chromatography is a sensitive and relatively inexpensive method that allows precise quantitative determination of the alkaloid content.
Flow-Injection Flame Atomic Absorption Spectrometric Determination of Trace Amounts of Cadmium in Solid and Semisolid Milk Products Coupling a Continuous Ultrasound-Assisted Extraction System with the Online Preconcentration on a Chelating Aminomethylphosphoric Acid Resin
Authors: Cancela Sheila , Yebra M Carmen 
Published: July 2020

Abstract
A new sensitive and low-cost method that combines continuous acid extraction, online preconcentration, and flame atomic absorption spectrometry for cadmium determination at g levels in solid and semisolid milk products is described. A continuous ultrasound-assisted extraction system is used to carry out the dynamic acid extraction step. The acid extract is preconcentrated online on a minicolumn packedwith a chelating resin (Chelite P,with aminomethylphosphoric acid groups), and the retained cadmium is elutedwith hydrochloric acid and continuously monitored by flame atomic absorption spectrometry. An experimental design (Plackett-Burman 263/16) is used to optimize the continuous extraction and the preconcentration step. The method allowed a total sampling frequency of 28 samples/h. A good precision of the whole procedure (3.0% relative standard deviation) for a cheese sample containing 0.103 0.004 g/g Cd (dry mass), a high enrichment factor (20.5), and detection and quantification limits of 0.014 and 0.067 g/g, respectively, for a 60 mg of sample were obtained with this methodology. The method was successfully applied to the determination of trace amounts of cadmium in solid and semisolid milk products, such as cheese and yogurt samples.
Clonal Structure and Variation in Virulence of Salmonella Enteritidis Isolated from Mice, Chickens, and Humans
Authors: Saeed A Mahdi , Walk Seth T , Arshad Mokhtar , Whittam Thomas S 
Published: July 2020

Abstract
The clonal analysis of a diverse collection of Salmonella Enteritidis indicates that most strains belong to a single multilocus genotype (i.e., ET-3) regardless of phage type, geographic origin, or time of isolation that spanned over 2 decades (1978 to 2004). Attachment and invasion assays, however, indicate that, among ET-3 isolates, there is a distinct invasive bacterial subpopulation that is more readily recovered from eggs and clinical cases in humans than from chicken cecal samples. These observations support the hypothesis that the specialized ability of S. Enteritidis to infect the avian reproductive tract and contaminate eggs has been critical in its emergence as a frequent cause of human illness.
Testing Green Coffee for Ochratoxin A, Part III: Performance of Ochratoxin A Sampling Plan
Authors: Vargas Eugenia A , Whitaker Thomas B , Santos Eliene A , Slate Andrew B , Lima Francisco B , Franca Regina C A 
Published: July 2020

Abstract
Green coffee shipments are often inspected for ochratoxin A (OTA) and classified into good or bad categories depending on whether the OTA estimates are above or below a defined regulatory limit. Because of the uncertainty associated with the sampling, sample preparation, and analytical steps of an OTA test procedure, some shipments of green coffee will be misclassified. The misclassification of lots leads to some good lots being rejected (sellers' risk) and some bad lots being accepted (buyers' risk) by an OTA sampling plan. Reducing the uncertainty of an OTA test procedure and using an accept/reject limit less than the regulatory limit can reduce the magnitude of one or both risks. The uncertainty of the OTA test procedure is most effectively reduced by increasing sample size (or increasing the number of samples analyzed), because the sampling step is the largest source of uncertainty in the OTA test procedure. The effects of increasing sample size and changing the sample accept/reject limit relative to the regulatory limit on the performance of OTA sampling plans for green coffee were investigated. For a given accept/reject limit of 5 μg/kg, increasing sample size increased the percentage of lots accepted at concentrations below the regulatory limit and increased the percentage of lots rejected at concentrations above the regulatory limit. As a result, increasing sample size reduced both the number of good lots rejected (sellers' risk) and the number of bad lots accepted (buyers' risk). For a given sample size (1 kg), decreasing the sample accept/reject limit from 5 to 2 μg/kg relative to a fixed regulatory limit of 5 μg/kg decreased the percentage of lots accepted and increased the percentage of lots rejected at all OTA concentrations. As a result, decreasing the accept/reject limit below the regulatory limit increased the number of good lots rejected (sellers' risk), but decreased the number of bad lots accepted (buyers' risk).
The Horwitz Ratio (HorRat): A Useful Index of Method Performance with Respect to Precision
Authors: Horwitz William , Albert Richard 
Published: July 2020

Abstract
The Horwitz ratio (HorRat) is a normalized performance parameter indicating the acceptability of methods of analysis with respect to among-laboratory precision (reproducibility). It is the ratio of the observed relative standard deviation among laboratories calculated from the actual performance data, RSDR (%), to the corresponding predicted relative standard deviation calculated from the Horwitz equation PRSDR (%) = 2C0.15, where C is the concentration found or added, expressed as a mass fraction. It is more or less independent of analyte, matrix, method, and time of publication (as a surrogate for the state of the art of analytical chemistry). It is now one of the acceptability criteria for many of the recently adopted chemical methods of analysis of AOAC INTERNATIONAL, the European Union, and other European organizations dealing with food analysis (e.g., European Committee for Standardization and Nordic Analytical Committee). The origin and applications of the formula are described. Consistent deviations from the ratio on the low side (values &lt;0.5) may indicate unreported averaging or excellent training and experience; consistent deviations on the high side (values &gt;2) may indicate inhomogeneity of the test samples, need for further method optimization or training, operating below the limit of determination, or an unsatisfactory method.
Determination of Fat,Moisture, and Protein in Meat and Meat Products by Using the FOSS FoodScan Near-Infrared Spectrophotometer with FOSS Artificial Neural Network Calibration Model and Associated Database: Collaborative Study
Authors: Anderson Shirley ,   Collaborators:, Aldana S , Beggs M , Birkey J , Conquest A , Conway R , Hemminger T , Herrick J , Hurley C , Ionita C , Longbind J , McMaignal S , Milu A , Mitchell T , Nanke K , Perez A , Phelps M , Reitz J , Salazar A , Shinkle T , Strampe M , Van Horn K , Williams J , Wipperfurth C , Zelten S , Zerr S 
Published: July 2020

Abstract
A collaborative study was conducted to evaluate the repeatability and reproducibility of the FOSS FoodScan near-infrared spectrophotometer with artificial neural network calibration model and database for the determination of fat, moisture, and protein in meat and meat products. Representative samples were homogenized by grinding according to AOAC Official Method 983.18. Approximately 180 g ground sample was placed in a 140 mm round sample dish, and the dish was placed in the FoodScan. The operator ID was entered, the meat product profile within the software was selected, and the scanning process was initiated by pressing the start button. Results were displayed for percent (g/100 g) fat, moisture, and protein. Ten blind duplicate samples were sent to 15 collaborators in the United States. The within-laboratory (repeatability) relative standard deviation (RSDr) ranged from 0.22 to 2.67% for fat, 0.23 to 0.92% for moisture, and 0.35 to 2.13% for protein. The between-laboratories (reproducibility) relative standard deviation (RSDR) ranged from 0.52 to 6.89% for fat, 0.39 to 1.55% for moisture, and 0.54 to 5.23% for protein. The method is recommended for Official First Action.
Validation of the SL3 -Lactam Test for Screening Milk in Compliance with U.S. Pasteurized Milk Ordinance: Performance-Tested MethodSM 040701
Authors: Salter Robert S , Conaway David , Markovsky Robert 
Published: July 2020

Abstract
The SL3 -Lactam Test is a 3 min, receptor-based lateral flow Rapid One Step Assay (ROSA) that detects 5 of 6 -lactam drugs approved for dairy cattle in the United States. The method was evaluated through the AOAC Research Institute Performance-Tested Method program following a U.S. Food and Drug Administration protocol. Three combined lots detected penicillin G 4.2 parts per billion (ppb), ampicillin 8.7 ppb, amoxicillin 7.8 ppb, cephapirin 16.0 ppb, and ceftiofur (total metabolites) 51 ppb at least 90 of the time, with 95 confidence as determined by dose response probit analysis. These detection levels are less than safe level/tolerances but not more than 50less. Lot repeatability was within 20. Incurred residues were detected comparably or more sensitively to fortified samples due to the cumulative effect of biologically active metabolites. There were no interferences from somatic cells at 1 M/mL, bacterial cells 500 000 colony-forming units/mL, or 30 other non--lactam drugs. These performances met approval conditions of the National Conference on Interstate Milk Shipments. Ruggedness conditions were incorporated into public health procedures for annual laboratory proficiency and certification.
Simultaneous Quantification of Withanolides in Withania somnifera by a Validated High-Performance Thin-Layer Chromatographic Method
Authors: Srivastava Pooja , Tiwari Neerja , Yadav Akhilesh K , Kumar Vijendra , Shanker Karuna , Verma Ram K , Gupt Madan M , Gupta Anil K , Khanuja Suman P S 
Published: July 2020

Abstract
This paper describes a sensitive, selective, specific, robust, and validated densitometric high-performance thin-layer chromatographic (HPTLC) method for the simultaneous determination of 3 key withanolides, namely, withaferin-A, 12-deoxywithastramonolide, and withanolide-A, in Ashwagandha (Withania somnifera) plant samples. The separation was performed on aluminum-backed silica gel 60F254 HPTLC plates using dichloromethanemethanolacetonediethyl ether (15 + 1 + 1 + 1, v/v/v/v) as the mobile phase. The withanolides were quantified by densitometry in the reflection/absorption mode at 230 nm. Precise and accurate quantification could be performed in the linear working concentration range of 66330 ng/band with good correlation (r2 0.997, 0.999, and 0.996, respectively). The method was validated for recovery, precision, accuracy, robustness, limit of detection, limit of quantitation, and specificity according to International Conference on Harmonization guidelines. Specificity of quantification was confirmed using retention factor (Rf) values, UV-Vis spectral correlation, and electrospray ionization mass spectra of marker compounds in sample tracks.
Simultaneous Determination of Phenolic Acids and Phthalide Compounds by Liquid Chromatography for Quality Assessment of Rhizoma Cnidii
Authors: Islam M Nurul , Yoo Hye Hyun , Sung Chung-Ki , Dong Mi-Sook , Park Young In , Jin Changbae , Kim Dong-Hyun 
Published: July 2020

Abstract
This paper describes a simple, rapid, and validated reversed-phase high-performance liquid chromatographic method developed for the determination of 4 major bioactive constituents, namely, chlorogenic acid, ferulic acid, senkyunolide A, and Z-ligustilide in Rhizoma Cnidii extract. A Capcell Pak C18 chromatographic column (150 4.6 mm, 3 m) was used with mobile phases consisting of 0.1 formic acid, acetonitrile, and methanol at a flow rate of 0.8 mL/min and UV detection at 285 nm. Comprehensive validation of the method included evaluation of linearity, repeatability, recovery, and stability. Excellent linear behavior (r2 &gt;0.99) was observed over the concentration range of 2100 g/mL for the compounds under investigation. Repeatability and accuracy were evaluated by intra- and interday assays; the relative standard deviation (RSD) values were 5.37 and accuracies ranged from 97.1 to 104.9. Recoveries of the compounds ranged from 94.2 to 104.2 with RSD values of 9.50. The developed method was successfully applied to the analysis of ethanolic extracts of Rhizoma Cnidii samples. As a result, the concentrations of chlorogenic acid, ferulic acid, Z-ligustilide, and senkyunolide A were determined to be 0.845.35, 0.451.65, 0.744.39, and 0.321.14 mg/g herb, respectively. Thus, the developed method was found to be accurate and reproducible and is considered suitable for the qualitative and quantitative analysis of Rhizoma Cnidii for bioactive compounds.