bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Volatile Compounds in Chrysanthemum morifolium by Microwave Distillation Solid-Phase Microextraction Coupled with GC/MS
Authors: Zhou Tao , Yang Bei , Zhang Haiying , Yu Yingjia , Chen Bin , Chen Yile , Duan Gengli 
Published: February 2020

Abstract
Microwave distillation with concomitant solid-phase microextraction (MD-SPME) coupled with GC/MS was developed for identifying volatile compounds in the dried flowers of Chrysanthemum morifolium (CM). Different experimental parameters, including SPME fiber coating, microwave power, irradiation time, and water volume were optimized. The best results were obtained using carboxen/polydimethylsiloxane fiber with microwave irradiation at 400 W for 3 min and the addition of 1 mL water into 1.0 g sample. The proposed method allowed the isolation, extraction, and concentration of volatile compounds to be completed in a single step. This MD-SPME-GC/MS method has also been compared to the conventional steam distillation method followed by GC/MS for this identification. Thirty-two volatile compounds were identified using the newly developed MD-SPME-GC/MS process. Relative standard deviation values of &lt;9.8 demonstrate good repeatability. In comparison, 27 compounds were identified by traditional steam distillation-GC/MS. Therefore, the proposed MD-SPME-GC/MS method is simple, rapid, and efficient for identifying volatile compounds in CM.
Determination of Organophosphorous Pesticide Phosphamidon in Environmental Water with Luminol Chemiluminescence Detection
Authors: Li Aifang , Liu Xiaoyu , Kong Juan , Hu Haoyu , Sun Linghui , Qian Zhen 
Published: February 2020

Abstract
A novel chemiluminescence method has been developed for the determination of the organophosphorous pesticide phosphamidon in environmental water samples, based on the reaction of phosphamidon with luminolH2O2 in an alkaline medium using sodium dodecyl benzene sulfonate as the enhancer. Under optimum conditions, the increased chemiluminescence intensity was proportional to the concentration of phosphamidon in the range of 0.011.0 g/mL and the detection limit was 0.0038 g/mL (3). The relative standard deviation was &lt;2 for 0.5 g/mL phosphamidon (n = 11). The proposed method was applied to the determination of phosphamidon residue in an environmental water sample with satisfactory results. Further study was focused on the mechanism of phosphamidon, and a possible mechanism was proposed.
Determination of Erythromycin and Tylosin Residues in Honey by LC/MS/MS
Authors: Granja Rodrigo , Nio Alfredo Montes , Zucchetti Roberto , Nio Rosario Montes , Patel Raj , Salerno Alessandro Gonzalez 
Published: February 2020

Abstract
Antibiotics are used in apiculture to protect bees against a variety of brood diseases. As a result of the development of resistance to oxytetracycline, erythromycin and tylosin are increasingly used for the prevention and treatment of these diseases. Therefore, Brazilian authorities have added these antibiotics to the National Regulatory Monitoring Program for the control of residues in honey. An analytical method has been developed for the determination of residues of erythromycin and tylosin in honey. The procedure involves solid-phase extraction of diluted honey samples with Bond Elut cartridges, followed by LC/MS with electrospray positive ionization in the multiple reaction monitoring mode. Two characteristic transitions were monitored for both drugs. Average analyte recoveries of erythromycin and tylosin ranged from 99 to 109 from sets of replicate honey samples fortified with drug concentrations of 5, 10, 15, and 20 g/kg. The method decision limits were determined to be 1.27 and 0.59 g/kg for erythromycin and tylosin, respectively. The detection capabilities were 5 and 5.2 g/kg for erythromycin and tylosin, respectively.
In-House Validation Study of the DuPont Qualicon BAX System Q7 Instrument with the BAX System PCR Assay for Salmonella (Modification of AOAC Official MethodSM 2003.09 and AOAC Research Institute Performance-Tested MethodSM 100201)
Authors: Tice George , Andaloro Bridget , White H Kirk , Bolton Lance , Wang Siqun , Davis Eugene , Wallace Morgan 
Published: February 2020

Abstract
In 2006, DuPont Qualicon introduced the BAX&lt;sup/&gt; system Q7 instrument for use with its assays. To demonstrate the equivalence of the new and old instruments, a validation study was conducted using the BAX system PCR Assay for Salmonella, AOAC Official MethodSM 2003.09, on three food types. The foods were simultaneously analyzed with the BAX system Q7 instrument and either the U.S. Food and Drug Administration Bacteriological Analytical Manual or the U.S. Department of AgricultureFood Safety and Inspection Service Microbiology Laboratory Guidebook reference method for detecting Salmonella. Comparable performance between the BAX system and the reference methods was observed. Of the 75 paired samples analyzed, 39 samples were positive by both the BAX system and reference methods, and 36 samples were negative by both the BAX system and reference methods, demonstrating 100 correlation. Inclusivity and exclusivity for the BAX system Q7 instrument were also established by testing 50 Salmonella strains and 20 non-Salmonella isolates. All Salmonella strains returned positive results, and all non-Salmonella isolates returned a negative response.
High-Throughput LC/MS/MS Analysis of Ruscogenin and Neoruscogenin in Ruscus aculeatus L.
Authors: Vlase Laurian , Kiss Béla , Balica Georgeta , Tas Mircea , Crisan Gianina , Leucuta Sorin E 
Published: February 2020

Abstract
A new, sensitive LC/MS/MS method was developed for the quantification of ruscogenin and neoruscogenin in hydrolyzed extracts from Ruscus aculeatus L. (Liliaceae). The two sapogenins were separated on a Zorbax SB-C18 column under isocratic conditions. The detection was performed in the multiple reaction monitoring mode using an ion trap mass spectrometer with an electrospray ionization source operated in positive ionization mode. For the quantification of the ruscogenin and neoruscogenin, calibration curves were constructed over the range of 21000 ng/mL. This is the first reported LC/MS/MS method for the simultaneous analysis of ruscogenin and neoruscogenin, and it showed superior sensitivity when compared with other assays described in the literature. The method has been successfully applied to quantify the two sapogenins in aerial (phylloclades) and underground parts (rhizomes, roots) of Ruscus aculeatus L.
Development of a New HPLC Method for the Simultaneous Determination of Ticarcillin and Clavulanic Acid in Pharmaceutical Formulations
Authors: Tsou Tai-Li , Lee Chiu-Wey , Wang Hsian-Jenn , Cheng Ya-Chung , Liu Yu-Tien , Chen Su-Hwei 
Published: February 2020

Abstract
A new HPLC method has been developed and validated for the simultaneous determination of ticarcillin (TIC) and clavulanic acid (CA) in pharmaceutical formulations. The HPLC separation was achieved on a -cyclodextrin column (Cyclobond I, 250 4.6 mm, 5 mm) with methanol16 mM pH 6.0 ammonium acetate buffer (50 + 50, v/v) mobile phase at a flow rate of 0.8 mL/min. Detection was at 220 nm. Validation of the method was performed by evaluating specificity, robustness, accuracy, and precision. The calibration curves were linear in the range of 1100 g/mL for CA and 2200 g/mL for TIC. The LOQs based on the standard regression lines were 0.42 and 1.42 g/mL for CA and TIC, respectively, and the LOD were 0.14 and 0.47 g/mL, respectively. Total recoveries of synthetic mixtures (CA:TIC = 1:10, 1:15, and 1:30) were 99.25100.99 for CA and 99.54100.82 for TIC. Compared with the U.S. Pharmacopeia method, the proposed method has the advantage of a relatively low flow rate and short analysis time. The proposed method was successfully applied for the simultaneous determination of these two drugs in sterilized H2O and 5 dextrose injection solutions.
Validation of iQ-Check E. coli O157:H7 Real-Time PCR Test Kit for Detection of Escherichia coli O157:H7 in Selected Foods
Authors: Lauer Wendy F , Tymciu Sylvie , Sidi Caroline D , Sonigo Pierre 
Published: February 2020

Abstract
iQ-Check E. coli O157:H7 (Bio-Rad Laboratories, Hercules, CA) is a real-time PCR kit for detection of E. coli O157:H7 from selected foods. Specific fluorescent oligonucleotide probes are used to detect target DNA during the amplification, by hybridizing to the amplicons. These fluorescent probes are linked to a fluorophore which fluoresces only when hybridized to the target sequence. Three foods (ground beef, apple cider, fresh spinach) were selected to compare the performance of iQ-Check E. coli O157:H7 to the U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook (MLG) reference method for ground beef and the U.S. Food and Drug Administration/Bacteriological Analytical Manual reference method for apple cider and fresh spinach. Three protocols were tested in this study: a shortened 8 h primary enrichment in buffered peptone water (BPW), a 24 h enrichment in BPW, and an enrichment in appropriate reference method enrichment broth. The iQ-Check E. coli O157:H7 method was able to identify more true/confirmed positive samples than the reference method. Inclusivity and exclusivity rates of the method were 100. iQ-Check E. coli O157:H7 performed as expected when minor procedural variations were introduced, validating the ruggedness of the method. There was no significant difference observed in performance over the shelf life of the kit.
Effects of DNA Extraction and Purification Methods on Real-Time Quantitative PCR Analysis of Roundup Ready Soybean
Authors: Demeke Tigst , Ratnayaka Indira , Phan Anh 
Published: February 2020

Abstract
The quality of DNA affects the accuracy and repeatability of quantitative PCR results. Different DNA extraction and purification methods were compared for quantification of Roundup Ready (RR) soybean (event 40-3-2) by real-time PCR. DNA was extracted using cetylmethylammonium bromide (CTAB), DNeasy Plant Mini Kit, and Wizard Magnetic DNA purification system for food. CTAB-extracted DNA was also purified using the Zymo (DNA Clean & Concentrator 25 kit), Qtip 100 (Qiagen Genomic-Tip 100/G), and QIAEX II Gel Extraction Kit. The CTAB extraction method provided the largest amount of DNA, and the Zymo purification kit resulted in the highest percentage of DNA recovery. The Abs260/280 and Abs260/230 ratios were less than the expected values for some of the DNA extraction and purification methods used, indicating the presence of substances that could inhibit PCR reactions. Real-time quantitative PCR results were affected by the DNA extraction and purification methods used. Further purification or dilution of the CTAB DNA was required for successful quantification of RR soybean. Less variability of quantitative PCR results was observed among experiments and replications for DNA extracted and/or purified by CTAB, CTAB+Zymo, CTAB+Qtip 100, and DNeasy methods. Correct and repeatable results for real-time PCR quantification of RR soybean were achieved using CTAB DNA purified with Zymo and Qtip 100 methods.
Determination of Six Pesticides in the Medicinal Herb Cordia salicifolia by Matrix Solid-Phase Dispersion and Gas Chromatography/Mass Spectrometry
Authors: De Carvalho Pedro Henrique Viana , De Menezes Prata Vanessa , Alves Pricles Barreto , Navickiene Sandro 
Published: February 2020

Abstract
A simple and effective extraction method based on matrix solid-phase dispersion was developed for acephate, chlorpropham, pyrimicarb, bifenthrin, tetradifon, and phosalone in leaves of the medicinal plant Cordia salicifolia, whose extracts are commercialized in Brazil as diuretic, appetite suppressant, and weight loss products. The determination method was GC/MS with selectedion monitoring. Different parameters of the method were evaluated, such as type of solid phase (C18, alumina, silica gel, and Florisil) and the amount of solid phase and eluent (dichloromethane, ethyl acetate, chloroform, and cyclohexane). The best results were obtained using 0.5 g herb sample, 0.5 g neutral alumina as the dispersant sorbent, 0.5 g C18 as the cleanup sorbent, and cyclohexanedichloromethane (3 + 1, v/v) as the eluting solvent. The method was validated using herb samples fortified with pesticides at different concentration levels (0.3, 0.5, and 1.0 mg/kg). Average recoveries (seven replicates) ranged from 67.7 to 129.9, with relative standard deviations between 6.3 and 26. Detection and quantitation limits for the herb ranged from 0.10 to 0.15 and 0.15 to 0.25 mg/kg, respectively.
Flame Atomic Absorption Spectrometry Determination of Trace Amount of Cobalt (II) After Preconcentration Using Modified Analcime Zeolite Loaded with bis(2-Hydroxy-1-Naphthaldimine)N-diethylene-triamine
Authors: Shamspur Tayebeh , Mostafavi Ali 
Published: February 2020

Abstract
A simple and sensitive flame atomic absorption spectrometry technique was developed for the determination of trace amounts of cobalt (Co) in various samples after adsorption on modified analcime using a recently synthesized tetradentate Schiff base ligand, bis(2-hydroxy-1-naphthaldimine)N-diethylene-triamine, by a column method in the pH range of 5 to 7, with a flow rate of 1 mL/min. The influence of flow rates of the stripping and sample solution, the amount of ligand, types of stripping, and the least amount of eluent required for elution of the Co ion from the column were investigated. The effects of interfering ions on the recovery of Co were studied. The method was successfully applied for determination of Co in water and plant samples. The maximum capacity of the modified sorbent was found to be 0.58 mg/g of Co(II); the preconcentration factor was 250. Linearity was maintained at 0.240 g/L in the original solution. The LOD was 1.44 102 g/L in the original solution.
Interlaboratory Validation of the Mehlich 3 Method as a Universal Extractant for Plant Nutrients
Authors: Schroder Jackie L , Zhang Hailin , Richards Jaben R , Payton Mark E 
Published: February 2020

Abstract
The Mehlich 3 (M3) method is widely used to extract plant-available phosphorus from soil over a wide range of pH values. The method is also used by many laboratories to determine multiple plant-available nutrients simultaneously. However, except for P, this method has not been statistically validated within and among laboratories. The objective of this study was to determine the repeatability (within-laboratory performance) and reproducibility (among-laboratories performance) of the M3 method for several different nutrients by using a wide variety of soils. An in-house homogeneity test was conducted for 11 soils. Three replicates of each of the 11 soils were sent to 23 domestic and international laboratories for analyses primarily for K, Ca, Mg, Zn, Mn, Fe, and Cu. Samples were scooped, weighed, or both scooped and weighed for extraction. The various nutrients in the extracts were quantified by the participating laboratories by using inductively coupled plasmaatomic emission spectrometry. Ranges (in parentheses) of the repeatability relative standard deviation (RSDr) values for the scooped samples were K (3.886.14), Ca (2.1910.6), Mg (2.275.73), Zn (4.1142.7), Mn (3.158.53), Fe (2.327.74), and Cu (3.6511.2). For the weighed samples, the ranges (in parentheses) of the RSDr values were K (1.654.65), Ca (1.4316.9), Mg (1.379.83), Zn (2.6033.0), Mn (1.614.90), Fe (1.564.47), and Cu (2.9517.9). Ranges (in parentheses) of the reproducibility relative standard deviation (RSDR) values for the scooped samples were K (7.4420.0), Ca (7.1033.5), Mg (7.6326.4), Zn (11.648.7), Mn (10.519.7), Fe (12.422.0), and Cu (8.8645.3). Ranges (in parentheses) of the RSDR values for the weighed samples were K (3.4712.7), Ca (7.6134.6), Mg (7.5329.0), Zn (10.649.2), Mn (6.5420.7), Fe (11.021.5), and Cu (9.7343.0). The Horwitz ratios (HorRat) were also used to evaluate the repeatability, HorRatr, and the reproducibility, HorRatR. Overall, the M3 method appears to be both repeatable and reproducible across the two categories for K, Mg, Zn, Mn, and Cu, and the vast majority of the HorRat values for both repeatability and reproducibility were within the acceptable range. However, a large number of soils in both the weighed and scooped categories displayed unacceptable HorRat values for the reproducibility of Ca and Fe, indicating that the M3 is not suitable for the extraction and quantitation of Ca and Fe in soils. The results of this study indicate that the M3 method for the determination of K, Mg, Zn, Mn, and Cu in soils is both accurate and precise when standardized procedures are used. The method has been proven to be suitable for use as a reference method for testing soil materials for extractable P, K, Mg, Zn, Mn, and Cu. Further study may be needed to confirm the suitability of the M3 method for Ca and Fe.
Trans Fat Labeling and Levels in U.S. Foods: Assessment of Gas Chromatographic and Infrared Spectroscopic Techniques for Regulatory Compliance
Authors: Mossoba Magdi M , Moss Julie , Kramer John K G 
Published: February 2020

Abstract
Trans fatty acids are found in a variety of foods like dairy and meat products, but the major dietary sources are products that contain commercially hydrogenated fats. There has been a renewed need for accurate analytical methods for the quantitation of total Trans fat since mandatory requirements to declare the amount of Trans fat present in food products and dietary supplements were issued in many countries. Official capillary GC and IR methodologies are the two most common validated methods used to identify and quantify Trans fatty acids for regulatory compliance. The present article provides a comprehensive discussion of the GC and IR techniques, including the latest attenuated total reflection (ATR)-FTIR methodology called the negative second derivative ATR-FTIR procedure, which is currently being validated in an international collaborative study. The identification and quantitation of Trans fatty acid isomers by GC is reviewed and an alternative GC method is proposed using two temperature programs and combining their results; this proposed method deals more effectively with the resolution of large numbers of geometric and positional monoene, diene, and triene fatty acid isomers present in ruminant fats. In addition, the different methylation procedures that affect quantitative conversion to fatty acid methyl esters are reviewed. There is also a lack of commercial chromatographic standards for many Trans fatty acid isomers. This review points to potential sources of interferences in the FTIR determination that may lead to inaccurate results, particularly at low Trans levels. The presence of high levels of saturated fats may lead to interferences in the FTIR spectra observed for Trans triacylglycerols (TAGs). TAGs require no derivatization, but have to be melted prior to IR measurement. While GC is currently the method of choice, ATR-FTIR spectroscopy is a viable, rapid alternative, and a complementary method to GC for a more rapid determination of total Trans fats for food labeling purposes.
Review of Methods for Preparation and Gas Chromatographic Separation of trans and cis Reference Fatty Acids
Authors: Delmonte Pierluigi , Kia Ali-Reza Fardin , Hu Qing , Rader Jeanne I 
Published: February 2020

Abstract
In recent years, several countries have implemented new regulations regarding the limitation or labeling of the trans fatty acid (TFA) content of foods and dietary supplements. GC methods for fatty acid (FA) analysis have been updated by improving the separation of TFAs from other FAs, especially trans- and cis-18:1, and by focusing more attention on the FAs contained in fats and oils in lower amounts. FA analysis is affected by the limited availability of reference materials. Identifications are frequently made simply by comparison with separations reported in the literature. This report describes the preparation of mixtures containing fatty acid methyl esters (FAMEs) that are not available as reference materials. These mixtures can be used for FAME identifications. The prepared mixtures are analyzed under the experimental conditions of the American Oil Chemists' Society (AOCS) Official Method Ce 1h-05 and AOCS Recommended Practice Ce 1j-07.
Comparative Validation Study to Demonstrate the Equivalence of a Minor Modification to AOAC Method 996.09 Visual Immunoprecipitate (VIP®) for E. coli O157:H7 Method to the Reference Culture Method
Authors: Feldsine Philip T , Kerr David E , Shen George , Lienau Andrew H 
Published: February 2020

Abstract
The Visual Immunoprecipitate (VIP®) for the Detection of Escherichia coli O157:H7 in Foods, AOAC Official Method 996.09, has been modified to change the color of the test and control lines of the device. A methods comparison study was conducted to demonstrate the equivalence of this modification to the reference culture method. Three foods were analyzed. In total, there were valid results from 225 samples and controls. Results showed that the VIP Gold® for E. coli O157:H7 is equivalent to the reference culture methods for the detection of E. coli O157:H7.
Evaluation of BD BBL CHROMagar Staph aureus Medium Using AOAC and ISO Culture Methods
Authors: Ritter Vicki , Kircher Susan , Sturm Krista , Warns Patty , Dick Nancy 
Published: February 2020

Abstract
BBL CHROMagar Staph aureus (CSA) medium was evaluated internally and externally for the isolation and enumeration of Staphylococcus aureus in cooked roast beef, smoked salmon, and shell eggs. All food matrixes were processed according to the AOAC Official Method 975.55 and ISO 6888-1:1999. Bacterial counts of S. aureus were compared on CSA to the reference media, Baird-Parker, at low, medium, and high contamination levels. Colony counts were converted to log10 for statistical analysis. Based on the paired t-test and one-way analysis of variance, no statistical difference was noted with the CSA method compared to the AOAC Official Method for the recovery of S. aureus for all food types and contamination levels. Compared to the ISO reference method, no statistical difference was found with the CSA method for any food type or contamination level, with the exception of low-level smoked salmon. A statistical difference was seen in the internal testing with the low-level contaminated smoked salmon where CSA recovered more colonies. The external testing showed no statistical difference with smoked salmon at the low level. The correlation coefficients ranged from 92.6 to 99.4, demonstrating good correlation for overall levels in all food types and methods. The sensitivity and specificity of the CSA method using known isolates was 100. The results of this study demonstrate that CSA is an effective medium for the isolation, enumeration, and presumptive identification of S. aureus in cooked roast beef, smoked salmon, and shell eggs in 24 h using ISO and AOAC official methods.