bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Fumonisin B1 in Botanical Roots by Liquid Chromatography with Fluorescence Detection: Single-Laboratory Validation
Authors: Oles Carolyn J , Trucksess Mary W
Published: February 2020

The accuracy, repeatability, and reproducibility characteristics of a published method for measuring levels of fumonisin B1(FB1) in botanical root products were determined by an AOAC single-laboratory validation procedure. Replicates of 10 test portions of each powdered root product (black cohosh, echinacea, ginger, ginseng, valerian, dong quai, and turmeric) at each spiking level (FB1 at 0, 50, 100, and 200 ng/g) were analyzed on 3 separate days. Test samples were extracted with methanolacetonitrilewater (25 + 25 + 100, v/v/v). The extracts were centrifuged, the supernatants diluted with phosphate-buffered saline (PBS) containing 1 Tween 20 and filtered, and the filtrates applied to an immunoaffinity column containing antibodies specific for fumonisins. After the column was washed sequentially with PBS and water, the toxin was eluted from the column with 80 methanol, and the eluate dried by lyophilization. The residue was reconstituted with 50 acetonitrile. FB1 was derivatized with a mixture of O-phthaldialdehyde and mercaptoethanol by using an LC autoinjector. Separations were performed with an RP-LC column, and the FB1 derivative was quantified by fluorescence detection. All root products were found to contain FB1 at <10 ng/g. Average within- and between-day recoveries of FB1 from the botanical roots ranged from 67 to 95 and from 68 to 100, respectively. Total RSD values for within- and between-day repeatability ranged from 5.5 to 26.4. HorRat values were <1.3 for all of the matrixes examined. The method meets the AOAC method performance criteria at levels of >50 ng/g for the seven botanical roots tested.
Determination of Deoxynivalenol in Processed Foods
Authors: Trucksess Mary W , Bao Lei , Weaver Carol M , White Kevin D
Published: February 2020

Deoxynivalenol (DON), commonly referred to as vomitoxin, belongs to a class of naturally occurring mycotoxins produced by Fusarium fungi. The presence of DON in foods is a human health concern. The frequency of occurrence of DON in wheat is high, although cleaning prior to milling can reduce DON concentration in final products, and food processing can partially degrade the toxin. This paper describes a method for the determination of DON in some major wheat food products, including bread, breakfast cereals, pasta, pretzels, and crackers. Test samples containing 5 polyethylene glycol were extracted with water. After blending and centrifuging, the supernatant was diluted with water and filtered through glass microfiber filter paper. The filtrate was then passed through an immunoaffinity column and the toxins eluted with methanol. The toxins were then subjected to RPLC separation and UV detection. The accuracy and repeatability characteristics of the method were determined. Recoveries of DON spiked at levels from 0.5 to 1.5 g/g in the five processed foods were >70. SD and RSD values ranged from 2.0 to 23.5 and from 2.0 to 23.2, respectively. HorRat values were <2 for all of the matrixes examined. The method was found to be acceptable for the matrixes examined. LC/MS/MS with multiple-reaction monitoring was used to confirm the identity of DON in naturally contaminated test samples.
Simple Gas Chromatographic Method for the Quantification of Total Cholesterol in Fish Meats
Authors: Memon Nusrat N , Sherazi Syed Tufail H , Talpur Farah N , Bhanger Muhammad I
Published: February 2020

Six fish speciesCirrhinus mrigala (Morakhi), Labeo rohita (Danbhro), Catla catla (Thalli), Wallago attu (Jarko), Ctenopharyngodon idella (Grass), and Cyprimus carpio (Gulfam)commonly found in the Pakistani Indus river, were selected for fat and cholesterol evaluation. Fat content was quantified by the Folch method and cholesterol content was determined by a simple GC method. The application of the proposed method to quantify cholesterol content revealed variations among the six breeds evaluated. The breeds studied contained 0.801.95 fat, indicating that all investigated fishes were lean; significant variation was found in cholesterol content, and ranged between 72 and 392 mg/100 g. Standard addition analyses showed that the method was accurate, as the recovery of cholesterol varied from 95 to 103, with a coefficient of variance not more than 5.6. The results showed that, after the development of suitable calibration, within 11 min, the cholesterol could be accurately determined by GC.
Rapid Determination of Fluoroquinolone Residues in Honey by a Microbiological Screening Method and Liquid Chromatography
Authors: Kanda Maki , Kusano Tomoto , Kanai Setsuko , Hayashi Hiroshi , Matushima Yoko , Nakajima Takayuki , Takeba Kazue , Sasamoto Takeo , Nagayma Toshijiro
Published: February 2020

A rapid and efficient method was developed for the simultaneous determination of seven fluoroquinolone (FQ) residues: norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin in honey. The samples were first screened with a microbiological method by using test plates made from metal-free purified agar seeded with Bacillus subtilis BGA. When a sample was found to contain FQ residues by using the microbiological method, it was analyzed by LC with fluorescence detection (LC/FL). FQs were extracted with Na2EDTA-McIlvaine buffer and purified by a dual SPE method in which a cation-exchange cartridge was connected to an anion-exchange cartridge. The overall recoveries of the seven FQs ranged from 70.0 to 92.1. The intra-assay and interassay CVs were 7.8 and 5.1, respectively. For the microbiological method, the LOD values ranged from 2 to 9 g/kg. For LC/FL, the LOQ values ranged from 2 to 7 g/kg. The developed method was used to analyze 70 honey samples. In 14 samples in which the microbiological method detected the presence of FQ residues, norfloxacin, ciprofloxacin, and enrofloxacin were identified by LC/FL.
Modern HPTLCA Perfect Tool for Quality Control of Herbals and Their Preparations
Authors: Meier Beat , Spriano Daniela
Published: February 2020

Herbals and herbal preparations are complex mixtures with numerous natural compounds in an uncharacterized matrixtruly multicomponent systems. This is in contrast to most of the samples of the pharmaceutical and, in part, the food industry, where primarily single compounds have to be analyzed. Recently, models for the characterization of multicomponent systems with near-IR, NMR, and MS combined with chemometric tools have been developed. However, the complexity and sophistication of such methods still prevent their general applicability to the QC of herbals. On the other hand, modern TLC is a well-established method with a long tradition. The typical chromatograms visualize even complex multicomponent systems in a special manner. The technique is rapid, comparatively simple, robust, and extremely versatile. HPTLC can not only confirm but also establish identity. It is also an ideal screening tool for adulterations and is highly suitable for evaluation and monitoring of cultivation, harvesting, and extraction processes and testing of stability. To substantiate these claims, several examples taken from daily work are provided and discussed in this paper.
Simultaneous Determination of Seven Alkaloids in Phellodendron chinense Schneid by High-Performance Liquid Chromatography
Authors: Liu Yong , Chen Juan , Li Xue-Hu , Shi Yan-Ping
Published: February 2020

By optimizing the extraction, separation, and analytical conditions, a reliable and accurate HPLC method coupled with a photodiode array detector was developed for simultaneous detection and quantification of seven alkaloids, i.e., (-)-(R)-platydesmin, noroxyhydrastinine, berberine, skimmianine, canthin-6-one, chilenine, and pteleine in huangbo (the bark of Phellodendron chinense), a commonly used herb in Traditional Chinese Medicine. The optimal condition for separation was achieved on a reversed-phase C18 column with a stepwise mobile phase gradient prepared from 0.1% phosphoric acid and acetonitrile. For all the alkaloids, a good linear regression relationship (r > 0.9997) was obtained between the peak area and concentration at the range of 0.5700 µg/mL. The LODs and LOQs for the analytes ranged from 0.07 to 0.28 µg/mL and from 0.28 to 1.12 µg/mL, respectively. The optimized method was applied to the determination of alkaloids in several P. chinense samples, and found to be feasible and reliable. This method and quantitative results can provide scientific and technical bases for setting up QC standards to assure the safety and quality of P. chinense bark raw material, as well as for proprietary Chinese medicine products containing P. chinense bark.
Fast HPLC Method Using Ion-Pair and Hydrophilic Interaction Liquid Chromatography for Determination of Phenylephrine in Pharmaceutical Formulations
Authors: Douòa Michal , Gibala Petr
Published: February 2020

A rapid procedure based on a direct extraction and HPLC determination with fluorescence detection of phenylephrine in pharmaceutical sachets that include a large excess of paracetamol (65 + 1, w/w), ascorbic acid (5 + 1, w/w), and other excipients (aspartame and sucrose) was developed and validated. The final optimized chromatographic method for ion-pair chromatography used an XTerra RP18 column, 3 µm particle size, 50 ⨯ 3.0 mm id. The mobile phase consisted of a mixture of acetonitrile and buffer (10 mM sodium octane-1-sulfonate, adjusted with H3PO4 to pH 2.2; 200 + 800, v/v), with a constant flow rate of 0.3 mL/min. The separation was carried out at 30C, and the injection volume was 3 µL. Fluorescence detection was performed at excitation and emission wavelengths of 275 and 310 nm, respectively. The mobile phase parameters, such as the organic solvent fraction (acetonitrile) in mobile phase as an organic modifier, the concentration of sodium octane-1-sulfonate as a counter-ion, temperature, and pH of mobile phase, were studied. As an alternative to ion-pair chromatography, hydrophilic interaction liquid chromatography (HILIC) was investigated using a Luna HILIC column, 3 m, 100 ⨯ 4.6 mm id. The mobile phase consisted of acetonitrile and buffer (5 M potassium dihydrogen phosphate, adjusted with H3PO4 to pH 2.5; 750 + 250, v/v) at a flow rate of 0.8 mL/min. The separation was carried out at 25°C, and the injection volume was 5 µL. The proposed method has an advantage of a very simple sample pretreatment, and is much faster than the currently utilized HPLC methods using gradient elution and UV detection. Commercial samples of sachets were successfully analyzed by the proposed HPLC method.
Rapid Determination of Fumonisins in Corn-Based Products by Liquid Chromatography/Tandem Mass Spectrometry
Authors: Li Wei , Herrman Timothy J , Dai Susie Y
Published: February 2020

A simple, fast, and robust method was developed for the determination of fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3) in corn-based human food and animal feed (cornmeal). The method involves a single extraction step followed by centrifugation and filtration before analysis by ultra-performance liquid chromatography/electrospray ionization (UPLC/ESI)-MS/MS. The LC/MS/MS method developed here represents the fastest and simplest procedure (<30 min) among both conventional HPLC methods and other LC/MS methods using SPE cleanup. The potential for high throughput analysis makes the method particularly beneficial for regulatory agencies and analytical laboratories with a high sample volume. A single-laboratory validation was conducted by testing three different spiking levels (200, 500, and 1000 ng/g for FB1 and FB2; 100, 250, and 500 ng/g for FB3) for accuracy and precision. Recoveries of FB1 ranged from 93 to 98% with RSD values of 3-8%. Recoveries of FB2 ranged from 104 to 108, with RSD values of 2-6%. Recoveries of FB3 ranged from 94% to 108%, with RSD values of 2-5%.
Determination of Vitamin A (Retinol) in Infant and Medical Nutritional Formulas with AOAC Method 992.06 Using a Modified Extraction Procedure: Single-Laboratory Validation
Authors: Thompson Linda B , Schimpf Karen J , Stiner Lisa A , Schmitz Daniel J
Published: February 2020

The applicability of AOAC Official MethodSM 992.06, Vitamin A (Retinol) in Milk-Based Infant Formula can be extended to specialty infant formulas, and medical and adult nutritional products with a few minor modifications to the sample preparation procedure. Currently, AOAC Official MethodSM9 92.06 is only applicable to milk-based infant formulas containing >500 IU vitamin A per reconstituted quart. When this method is used as written to test specialty infant formulas, vitamin A recoveries are low compared to results generated with alternate validated vitamin A methods. AOAC Method 992.06 vitamin A recoveries can be improved significantly in specialty infant formulas if the amount of potassium hydroxide used during the saponification step is doubled. With this one minor modification to the sample preparation procedure, AOAC Method 992.06 demonstrates acceptable precision and accuracy for the quantitation of vitamin A (retinol) in specialty infant formulas, milk- and soy-based infant formulas, and adult and medical nutritionals. Because increasing the amount of potassium hydroxide can cause emulsions to form, 24 mL aliquots of reagent alcohol may need to be added to some samples to separate the organic and aqueous layers during the extraction step. A single-laboratory validation of these modifications was completed. During validation, 15 different product matrixes were analyzed. The intermediate precision averaged 2.70% RSD, and spike recovery data averaged 96.3%.
SYBR Green Real-Time PCR Used to Detect Celery in Food
Authors: Wu Yajun , Chen Ying , Wang Bin , Gao Yunhua , Bai Liqun , Wang Haiyan
Published: February 2020

Celery was found to provoke human allergenic response in some countries. Labeling of celery ingredients was required by the European Union, and the threshold set at 10 mg/kg (0.001%). In our study, a celery mannitol transporter (Mat3) gene-based detection method was established by means of SYBR Green real-time PCR technique. No cross-reactivity was found between celery and the other food materials. Absolute detection limit (LODa), relative detection limit (LODr), and practical detection limit (LODp) of the method were determined through experiments on pure celery DNA, DNA mix, and spiked food samples. The method was able to detect 0.001 raw food sample and 0.01 heated food sample. The utility of the method was confirmed by the investigation of 13 commercial foods.
Determination of Quaternary Ammonium Compounds by Potentiometric Titration with an Ionic Surfactant Electrode: Single-Laboratory Validation
Authors: Price Randi , Wan Ping
Published: February 2020

A potentiometric titration for determining the quaternary ammonium compounds (QAC) commonly found in antimicrobial products was validated by a single laboratory. Traditionally, QACs were determined by using a biphasic (chloroform and water) manual titration procedure. Because of safety considerations regarding chloroform, as well as the subjectivity of color indicator-based manual titration determinations, an automatic potentiometric titration procedure was tested with quaternary nitrogen product formulations. By using the Metrohm Titrando system coupled with an ionic surfactant electrode and an Ag/AgCl reference electrode, titrations were performed with various QAC-containing formulation products/matrixes; a standard sodium lauryl sulfate solution was used as the titrant. Results for the products tested are sufficiently reproducible and accurate for the purpose of regulatory product enforcement. The robustness of the method was measured by varying pH levels, as well as by comparing buffered versus unbuffered titration systems. A quantitation range of 11000 ppm quaternary nitrogen was established. Eight commercially available antimicrobial products covering a variety of matrixes were assayed; the results obtained were comparable to those obtained by the manual titration method. Recoveries of 94 to 104% were obtained for spiked samples.
Determination of PAHs, PCBs, Minerals, Trace Elements, and Fatty Acids in Rapana thomasiana as an Indication of Pollution
Authors: Namiesnik Jacek , Szefer Piotr , Sliwka-Kaszynska Magdalena , Moncheva Snejana , Arancibia-Avila Patricia , Toledo Fernando , Ham Kyung-Sik , Kang Seong-Gook , Gorinstein Shela
Published: February 2020

The aim of this investigation was to introduce several analytical methods for determination of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), minerals, trace elements, and fatty acids in Rapana thomasiana as a marine pollution indicator organism. The chemical differences of the gastropod Ra. thomasiana from polluted and nonpolluted sites of the Black Sea on the Bulgarian coast were investigated. Chromatography and high-resolution inductively coupled plasma/MS analyses were used for evaluation of PAHs, PCBs, fatty acids, minerals, and trace elements. These methods can be applied to other marine products.
Quantitative Analysis of Closantel and Rafoxanide in Bovine and Ovine Muscles by High-Performance Liquid Chromatography with Fluorescence Detection
Authors: Yeung Hoi-Sze , Ching Wing-Hong , Lai Shirley Sau-Ling , Lee Wai-On , Wong Yiu-Tung
Published: February 2020

An HPLC method with a fluorescence detector (HPLC-FLD) was described for the quantitative determination of closantel and rafoxanide in bovine and ovine muscles. A structural analog closely related to rafoxanide, viz., N-[4-(4-chlorophenoxy) phenyl]-2-hydroxy-3,5-diiodobenzamide, was synthesized as an internal standard. Bovine and ovine muscles were extracted with acetonitrileacetone (60 + 40, v/v) followed by cleanup on mixed mode anionic exchange SPE cartridges. After evaporation and reconstitution with the mobile phase, the sample was analyzed by HPLC-FLD using internal standard calibration. The method was validated by using fortified bovine and ovine muscles at 15, 30, and 60 µg/kg. The accuracy and RSD were 70110% and 10%, respectively.
Determination of Trace Amounts of Pd(II) Ions in Water and Road Dust Samples by Flame Atomic Absorption Spectrometry After Preconcentration on Modified Organo Nanoclay
Authors: Afzali Daryoush , Mostafavi Ali , Afzali Zahra
Published: February 2020

This paper describes the application of organo nanoclay, an easily prepared and stable solid sorbent, to the preconcentration of trace amounts of palladium ions in aqueous solution. The organo nanoclay was prepared by adding tetradecyldimethylbenzylamonium chloride onto montmorillonite, which was then modified with 1-(2-pyridylazo)-2-naphthol. The modified nanoclay was used as a solid sorbent for separation and preconcentration of trace amounts of Pd(II) ions, and a simple, sensitive, and economical method was developed for determination of trace amounts of palladium by flame atomic absorption spectrometry. The sorption of Pd(II) ions was quantitative in the pH range of 1.55.0, whereas quantitative desorption occurred with 5.0 mL of a mixture containing 1.0 M thiourea and 1.0 M HCl. The RSD of the method was 2.1 (n = 10; concn = 0.5 g/mL), and the LOD (3bl; = SD and bl = blank) was 0.1 ng/mL. The calibration curve was linear for concentrations of 0.58.0 g/mL in the initial solution, and the preconcentration factor was 140. The maximum capacity of the sorbent was 2.4 mg Pd(II)/g modified organo nanoclay. The influences of the experimental parameters, including sample pH, eluant volume, eluant type, sample volume, and interfering ions, on the recoveries of the palladium ion were investigated. The proposed method was applied to the preconcentration and determination of palladium in different samples.
A Fast, Inexpensive, and Safe Method for Residue Analysis of Meptyldinocap in Different Fruits by Liquid Chromatography/Tandem Mass Spectrometry
Authors: Banerjee Kaushik , Dasgupta Soma , Jadhav Manjusha R , Naik Dattatraya G , Ligon Axel Patrick , Oulkar Dasharath P , Savant Rahul H , Adsule Pandurang G
Published: February 2020

An analytical method is reported for residue analysis of the fungicide meptyldinocap in different fruit matrixes that involves extraction with ethyl acetate, hydrolysis of the residues with ethanolamine, and determination by LC/MS/MS. The method involves extraction of 10 g sample with 10 mL ethyl acetate; evaporation of the ethyl acetate phase to dryness, and subsequent hydrolysis of the residues to 4,6-dinitro-2-(1-methylheptyl) phenol on reaction with 1 ethanolamine. The pH of this hydrolyzed product was neutralized with formic acid and analyzed by LC/MS/MS. The hydrolysis reaction followed pseudo-first-order kinetics, and the reaction product was spectroscopically confirmed as 2-(1-methylheptyl)-4,6-dinitrophenol. The method offered >80 recoveries at an LOQ of 10 ng/g for grape and mango, 25 ng/g for pomegranate with intralaboratory Horwitz ratio <0.5, and measurement uncertainties <10 at LOQ levels. Considering first-order rate kinetics, activation energy, enthalpy of activation, and entropy of activation varied as solvent > mango > grape > pomegranate. Free energy of activation at 298 K was higher than at 280 K and was similar for solvent and three matrixes at both temperatures.
Evaluation of VIDAS® Listeria species Xpress (LSX) Immunoassay Method for the Detection of Listeria species in Foods: Collaborative Study
Authors: Johnson Ronald L , Jechorek Robert P ,   Collaborators:, Andrews H , Bautista P , Bird P , Blamey S , Connell E , Cooper C , Cooper W D , Crowley E , Doane C , Elton S , Falkenberg R , Fernandes-Monteiro C , Gharst T , Gonzalez E , Hawes B , Hemming B , High E , Hsu D , Iannucci C , Kora L , Lara A , Lee M , Masanz G , Mattson D , Okolo C , Parra G , Ryan E , Torontali M , Vega H
Published: February 2020

In a multilaboratory study, the effectiveness of an alternative method for rapid screening of Listeria species compared to traditional reference methods was demonstrated in a variety of food products. A collaborative study was conducted to compare the VIDAS® Listeria species Xpress (LSX) method and the standard cultural methods for the detection of Listeria species in foods. Six food types were tested: vanilla ice cream, cheddar cheese, raw ground beef, frozen green beans, deli turkey, and cooked shrimp. Each food, inoculated with a different Listeria strain at two levels and uninoculated test portions, was analyzed by each method. A total of 15 laboratories representing government and industry participated. In this study 1134 tests were analyzed in the statistical analysis. There were 490 positives by the VIDAS LSX method using the sample boiling step, 483 positives by the VIDAS LSX method using the Heat and Go system, and 439 positives by the standard culture methods. Overall, the Chi-square result for the VIDAS LSX method with boiling for all foods was 7.25, indicating a significant statistical difference between the VIDAS method and the standard methods at the 5% confidence. For the VIDAS LSX method with the Heat and Go system, the Chi-square result for all foods was 5.37, indicating a significant statistical difference between the VIDAS LSX assay with the Heat and Go system and the standard methods at the 5% level of significance. In both cases, the VIDAS method was more sensitive than the standard methods. The LSX method detects Listeria species in foods with negative or presumptive positive results in a minimum of 30 h compared to at least 5 days for the cultural methods. Based on the results of this collaborative study, it is recommended that the VIDAS LSX method be adopted as an AOAC Official MethodSM for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry.
HPLC Analysis of Kaempherol and Quercetin Derivatives Isolated by Different Extraction Techniques from Plant Matrix
Authors: Skalicka-Woźniak Krystyna , Szypowski Janusz , Głowniak Kazimierz
Published: February 2020

Soxhlet extraction, ultrasound extraction, and accelerated solvent extraction (ASE), followed by RP-HPLC with a photodiode array detector was used for the determination of flavonoids in fruits of Peucedanum alsaticum. Three compounds were identified: a kaempherol derivative (astragalin), and two quercetin derivatives (quercitrin and hiperoside). The highest extraction yields of the selected compounds were obtained by use of exhaustive ASE.
A GC-ECD Method for Estimation of Free and Bound Amino Acids, γ-Aminobutyric Acid, Salicylic Acid, and Acetyl Salicylic Acid from Solanum lycopersicum (L.)
Authors: Meher Hari Charan , Gajbhiye Vijay T , Singh Ghanendra
Published: February 2020

A gas chromatograph with electron capture detection method for estimation of selected metabolites—amino acids (free and bound), γ-aminobutyric acid (GABA), salicylic acid (SA), and acetyl salicylic acid (ASA) from tomato—is reported. The method is based on nitrophenylation of the metabolites by 1-fluoro-2,4-dinitrobenzene under aqueous alkaline conditions to form dinitrophenyl derivatives. The derivatives were stable under the operating conditions of GC. Analysis of bound amino acids comprised perchloric acid precipitation of protein, alkylation (carboxymethylation) with iodoacetic acid, vapor-phase hydrolysis, and derivatization with 1-fluoro-2,4-dinitrobenzene in that order. The metabolites were resolved in 35 min, using a temperature-programmed run. The method is rapid, sensitive, and precise. It easily measured the typical amino acids (aspartate, asparagine, glutamate, glutamine, alanine, leucine, lysine, and phenylalanine) used for identification and quantification of a protein, resolved amino acids of the same mass (leucine and isoleucine), satisfactorily measured sulfur amino acids (methionine, cystine, and cysteine), and quantified GABA, SA, and ASA, as well. The developed method was validated for specificity, linearity, and precision. It has been applied and recommended for estimation of 25 metabolites from Solanum lycopersicum (L.).
Cloud-Point Extraction of Rhodamine 6G by Using Triton X-100 as the Non-Ionic Surfactant
Authors: Duran Celal , Ozdes Duygu , Bulut Volkan Numan , Tufekcī Mehmet , Soylak Mustafa
Published: February 2020

Cloud-point extraction (CPE) using the non-ionic surfactant Triton X-100 was used successfully to remove a highly toxic dye, rhodamine 6G (R6G), from water and wastewater. The effects of different analytical parameters such as pH, concentration of Triton X-100 (TX-100) and salts, equilibrium temperature, and incubation time on the efficiency of the extraction of R6G were studied in detail, and optimum conditions for dye extraction were obtained. Thermodynamic parameters including changes in Gibbs free energy, enthalpy, and entropy were also calculated, and these parameters indicated that the CPE of R6G was feasible, spontaneous, and endothermic in the temperature range of 75–95°C. The equilibrium solubilization capacity of TX-100 was found to be 1.10 mmol/mol by using Langmuir isotherm models. No significant interference effects were observed in the presence of phenol and its derivatives, some acidic and basic dyes and most of the anions and cations. It was concluded that the CPE process described in this paper can be an alternative technique for removal of dyes and other pollutants from waters and wastewaters.
Determination of Polyphenols in Mentha longifolia and M. piperita Field-Grown and In Vitro Plant Samples Using UPLC-TQ-MS
Authors: Krzyzanowska Justyna , Janda Bogdan , Pecio Lukasz , Stochmal Anna , Oleszek Wieslaw , Czubacka Anna , Przybys Marcin , Doroszewska Teresa
Published: February 2020

Nine polyphenols in the aerial parts of Mentha longifolia have been separated by chromatographic techniques. Their structures have been confirmed by HPLC/electrospray ionization-MS/MS. The compounds identified included rosmarinic acid, salvianolic acid L, dedihydro–salvianolic acid, luteolin–glucuronide, luteolin–diglucuronide, luteolin–glucopyranosyl–rhamnopyranoside, and eriodictyol–glucopyranosyl–rhamnopyranoside. The extracts of M. longifolia and M. piperita field plants, in vitro plants, callus tissues, and cell suspension cultures were profiled, and their polyphenol composition was compared in different tissues and quantified using ultra-performance column liquid chromatography (UPLC)/triple-quadrupole-MS in the selected-ion recording detection mode. Determination of desired compounds was based on calibration curves obtained for standards, which were previously isolated from M. longifolia aerial parts. The UPLC profiles revealed considerable differences in the synthesis of secondary metabolites among samples coming from field plants, in vitro plants, callus tissues, and cell suspension cultures. Plant tissues coming from field cultivation (for both M. piperita and M. longifolia) contained several phenolic compounds (flavonoids and phenolic acids), whereas plants from in vitro conditions, callus tissues, and suspension cultures contained only a few of them. Rosmarinic acid dominated in all of these samples. These results show that under in vitro conditions, the metabolism of phenolics undergoes a fundamental change.
ELISA Kit for Mustard Protein Determination: Interlaboratory Study
Authors: Cuhra Petr , Gabrovská Dana , Rysová Jana , Hanák Petr , Štumr Frantiek ,   Collaborators:, Baranda A , Barov S , Brychta J , Bulawov H , eni A , Dvorsk P , Guisantes Del Barco J A , Iametti S , Jimenez E , Karulnov L , Kubk M , Langerholc T , Laukkanen M-L , Malmheden Yman; I , Martnez de Maraon I , Martnez Quesada J , Pardo M A , Piknov L , Plicka J , Postigo Resa I , Suen Pardo; E , Takkinen K , Tomkov K
Published: February 2020

An interlaboratory study in 12 laboratories was performed to prove the validation of the ELISA method developed for the quantitative determination of mustard protein in foods. The ELISA kit used for this study is based on rabbit polyclonal antibody. This kit did not produce any false-positive results or cross-reactivity with in-house validation for a broad range of food matrixes with no detectable mustard protein. All participants obtained the Mustard ELISA kit with standard operational procedures, a list of samples, samples, and a protocol for recording test results. The study included 15 food samples and two spiked samples. Seven food matrix samples of zero mustard content and four samples with mustard declared as an ingredient showed mustard protein content lower than that of the first standard (0.42 mg/kg). Four samples with mustard declared as an ingredient revealed mustard protein content above 12.5 mg/kg (the highest standard). The statistical tests (Cochran, Dixon, and Mandel) and analysis of variance were used to evaluate the interlaboratory study results. Repeatability and reproducibility limits, as well as an LOQ (1.8 mg mustard proteins/kg) and LOD (0.5 mg mustard proteins/kg), for the kit were calculated.
Development and Validation of Micellar Liquid Chromatographic Methods for the Determination of Antibiotics in Different Matrixes
Authors: Rambla-Alegre Maria , Esteve-Romero Josep , Carda-Broch Samuel
Published: February 2020

Antibiotics are the most important bioactive and chemotherapeutic compounds to be produced by microbiological synthesis, and they have proved their worth in a variety of fields, such as medicinal chemistry, agriculture, and the food industry. Interest in antibiotics has grown in parallel with an increasingly high degree of productivity in the field of analytical applications. Therefore, it is necessary to develop chromatographic procedures capable of determining various drugs simultaneously in the shortest possible time. Micellar liquid chromatography (MLC) is an RP-HPLC technique that offers advantages over conventional HPLC as far as sample preparation, selectivity, and versatility are concerned. Its main advantage is that samples can be injected directly into the chromatographic system with no previous preparation step. This paper mainly focuses on the results of the authors' own recent research and reports the chromatographic conditions for determination of various antibiotics (penicillins, quinolones, and sulfonamides) in different matrixes (pharmaceuticals, biological fluids, and food). The work of other authors on MLC-based antibiotic determination has been included.
Rapid Microwave-Assisted Extraction and HPTLC- Photodensitometric Method for the Quality Assessment of Boerhaavia diffusa L.
Authors: Bhope Shrinivas G , Ghosh Vivek K , Kuber Vinod V , Patil Manohar J
Published: February 2020

A rapid and cost-effective method for the extraction of rotenoids in Boerhaavia diffusa L., based on the use of microwave-assisted extraction (MAE), is proposed. The conventional reflux, soxhlet, and maceration extraction methods were also conducted to validate the reliability of the new method. Under the optimized conditions, two rotenoids (boeravinone B and E) were extracted and quantified by HPTLC. The yield of boeravinone B and E achieved by MAE was 0.15 and 0.32% (w/w), respectively. The result showed that MAE-HPTLC is a simple, rapid, and solvent-sparing method for the extraction and quantitation of boeravinone B and E from B. diffusa L.
Dietary Supplement Laboratory Quality Assurance Program: The First Five Exercises
Authors: Phillips Melissa M , Rimmer Catherine A , Wood Laura J , Lippa Katrice A , Sharpless Katherine E , Duewer David L , Sander Lane C , Betz Joseph M
Published: February 2020

The National Institute of Standards and Technology (NIST) has established a Dietary Supplement Laboratory Quality Assurance Program (DSQAP) in collaboration with the National Institutes of Health Office of Dietary Supplements. Program participants measure concentrations of active and/or marker compounds as well as nutritional and toxic elements in food and dietary supplements distributed by NIST. Data are compiled at NIST, where they are analyzed for accuracy relative to reference values and concordance among the participants. Performance reports and certificates of completion are provided to participants, which can be used to demonstrate compliance with current Good Manufacturing Practices as promulgated by the U.S. Food and Drug Administration. The DSQAP has conducted five exercises to date, with total participation including more than 75 different laboratories and many more individual analysts.
Simultaneous Determination of Benzimidazoles and Their Metabolites in Plasma Using High-Performance Liquid Chromatography/Tandem Mass Spectrometry: Application to Pharmacokinetic Studies in Rabbits
Authors: Zhu Xinle , Wang Shuhuai , Qi Liu , Xu Qian , Zhang Congmin , Xu Shixin , Wang Xia , Li Dan , Hu Haiyan
Published: February 2020

An HPLC/MS/MS method was developed for the simultaneous determination of the following benzimidazole anthelmintics and metabolites in plasma: flubendazole, albendazole, fenbendazole, mebendazole, thiabendazole, hydrolyzed flubendazole, albendazole sulfoxide, albendazole sulfone, albendazole aminosulfone, oxfendazole, fenbendazole sulfone, aminomebendazole, hydroxymebendazole, and 5-hydroxythiabendazole. The sample preparation process involved a pH-dependent extraction of the analytes. Chromatographic separation was performed on a C18 column with a mobile phase gradient starting with methanol–water (20 + 80, v/v) containing 0.1% formic acid. The overall average recoveries of the analytes based on a matrix-matched calibration ranged from 75.0 to 120.0%, with RSD values of <20.0%. The LODs ranged from 0.08 to 2.0 μg/kg and the LOQs from 0.3 to 5.0 μg/kg. The validated method was used in pharmacokinetic studies of benzimidazole compounds in rabbits, and the elimination of the metabolites was measured quantitatively.
Evaluation of TA10 Broth for Recovery of Heat- and Freeze-Injured Salmonella from Beef
Authors: -Horikoshi Naoko Kamisaki , Okada Yukio , Takeshita Kazuko , Sameshima Takashi , Kawasaki Susumu , Kawamoto Shinichi , Fratamico Pina M
Published: February 2020

The Bacteriological Analytical Manual (BAM) Salmonella pre-enrichment broth [lactose (LAC) broth], buffered peptone water, and universal pre-enrichment (UP) broth were compared with TA10 broth, developed in our laboratory, for recovery of heat- and freeze-injured Salmonella (55°C for 2–20 min and –20°C for 2 months, respectively) from beef. Beef samples were contaminated with single Salmonella serovars, and contamination levels of 0.44 to <0.001 most probable number (MPN)/g and 0.74 to 0.14 MPN/g were used for heat- and freezing-induced injury studies, respectively. Twenty test portions (25 g) of the contaminated beef were pre-enriched in each broth, and the BAM Salmonella culture method was used thereafter. There was a significant difference (χ2 = 7.73) in recovery of heat-injured Salmonella between TA10 broth and LAC broth, 189 (67.5%) versus 156 (55.7%) positive samples, respectively, determined by plating onto selective agars and identification by biochemical tests. For the recovery of freeze-injured Salmonella, there was a significant difference (χ2 = 24.7) between TA10 and LAC broth, 189 (72.7%) versus 133 (51.2%) positive samples, respectively. TA10 broth was more effective than LAC broth and UP broth for recovery of freeze-injured Salmonella. The results indicate that TA10 broth should be used instead of LAC broth for testing of beef that may be contaminated with heat- and freeze-injured Salmonella spp.
An Efficient and Simultaneous Analysis of Caffeine and Paracetamol in Pharmaceutical Formulations Using TLC with a Fluorescence Plate Reader
Authors: Tavallali Hossein , Zareiyan J. S Faraneh , Naghian Maryam
Published: February 2020

A simple, rapid, and effcient method using TLC with a ﬂuorescence plate reader has been described for simultaneous determination of caffeine and paracetamol. Determination was carried out using the ﬂuorescencequenching action of caffeine and paracetamol on a TLC plate with a ﬂuorescent indicator at λ ex = 254 nm in the linear ranges of 0.2–1.9 and 0.03–1.5 µg/L, respectively. Separation of caffeine and paracetamol were performed on the TLC plate, and the best results were obtained using the optimized mobile phase n-hexane–ethyl acetate–ethanol (2.5 + 1.5 + 0.4, v/v). Some important parameters, such as solvent type and ratio of the mobile phase, the presence of other components, and instrumental parameters, were studied. Caffeine and paracetamol detection limits were 0.025 and 0.032 µg/L, and RSD values for 0.6 µg/L caffeine and 0.06 µg/L paracetamol (n = 5) were 1.93 and 2.06%, respectively. Using this technique, some pharmaceuticals containing caffeine and paracetamol were analyzed with satisfactory results.
Reveal® Salmonella Enteritidis Test for Detection of Salmonella Enteritidis in Shell Eggs and Environmental Samples
Authors: Jagadeesan Balamurugan , Curry Stephanie , Foti Debra , Peterson Lauren , Wilson Rebecca , Mozola Mark
Published: February 2020

Reveal®Salmonella Enteritidis (SE) is a lateral flow-based immunodiagnostic assay used for rapid detection of Salmonella enterica serovar Enteritidis from pooled shell eggs and environmental samples. This assay uses highly specific antibodies to accurately detect S. Enteritidis. Studies were conducted to compare the performance of this test against reference procedures for detection of S. Enteritidis from both pooled shell eggs and environmental samples. Pooled shell eggs were inoculated with low levels of S. Enteritidis and were enriched according to the procedure prescribed by the U.S. Food and Drug Administration. Uninoculated samples were included in each trial. Reveal SE exhibited 100% sensitivity and 100% specificity in comparison to the reference method in all trials. An abbreviated 48 h/(no hold) enrichment procedure was also developed and validated for detection of S. Enteritidis from pooled shell egg samples. This shortened enrichment procedure can be used in conjunction with the Reveal SE test and offers a significant enrichment time savings of 96 h. Chi-square analysis revealed that there was no significant difference between the abbreviated Reveal method and the reference procedure for detection of S. Enteritidis from pooled shell egg samples. Out of 245 natural drag swabs screened internally, only three samples tested Reveal SE positive and were confirmed by the reference procedure, resulting in 100% sensitivity and 100% specificity. An external laboratory screened 147 poultry house environmental samples and obtained 35 Reveal SE confirmed positives for Reveal SE sensitivity of 100% and specificity of 90%. Inoculation trials with drag swabs resulted in 96% sensitivity and 100% specificity. Thus, these data demonstrate that Reveal SE is a highly sensitive and specific assay for the detection of S. Enteritidis from both pooled shell eggs and environmental samples.
Determination of Vitamin B12 in Fortified Bovine Milk- Based Infant Formula Powder, Fortified Soya-Based Infant Formula Powder, Vitamin Premix, and Dietary Supplements by Surface Plasmon Resonance: Collaborative Study
Authors: Vyas Pathik , O'kane Anthony A ,   Collaborators:, Ager E , Crooks S , Elliott C , Eriksson S , Fraser R , Hallstrom M , Hayes J , Indyk H , Jozwiak S , Kong K , McMahon A , Meneely J , Ming W W , Mitchell B , Sullivan D , Thompson C , Vuyani M , Vyas S , Wilson P
Published: February 2020

A collaborative study was conducted on an inhibition-based protein-binding assay using the Biacore Q™ biosensor instrument and the Biacore Qﬂex™ Kit Vitamin B12 PI. The samples studied included infant formula, cereals, premixes, vitamin tablets, dietary supplements, and baby food. The collaborative study, which involved 11 laboratories, demonstrated that the assay showed an RSDr of 1.59–27.8 and HorRat values for reproducibility of 0.34–1.89 in samples with levels ranging from ppm to ppb. The assay studied is a label-free protein binding-based assay that uses the principle of surface plasmon resonance (SPR) to measure the interaction between vitamin B12 and a specifc binding protein. A Biacore Q biosensor uses this principle to detect binding directly at the surface of a sensor chip with a hydrophilic gold-dextran surface. The instrument passes a mixture of prepared sample extract and binding protein solution across a covalently immobilized vitamin B12 chip surface, and the response is given as free-binding protein as the mixture binds to the immobilized surface. This technique uses the specifcity and robustness of the protein-ligand interaction to allow minimal sample preparation and a wide range of matrixes to be analyzed rapidly. The reagents and accessories needed to perform this assay are provided as the ready-to-use format “Qﬂex Kit Vitamin B12 PI.” The method is intended for routine use in the quantitative determination of vitamin B12 (as cyanocobalamin) in a wide range of food products, dietary vitamin supplements, and multivitamin premixes.
Simultaneous Determination of Chromium, Selenium, and Molybdenum in Nutritional Products by Inductively Coupled Plasma/Mass Spectrometry: Single-Laboratory Validation
Authors: Pacquette Lawrence H , Szabo Andre , Thompson Joseph T
Published: February 2020

An inductively coupled plasma/MS method was developed for the simultaneous determination of Cr, Se, and Mo in infant formulas and other nutritional products. All samples were digested using a closed vessel microwave oven system, together with Ni and Te internal standards. The practical quantitation limits for Cr, Se, and Mo were 0.4, 0.2, and 0.4 ng/mL, respectively; dilution factors were 250 for powders and 50 for liquids. The Cr, Se, and Mo concentrations in 10 nutritional products were within specifcation limits, and within-day and day-to-day (6 independent days) precision values were <5% RSD. For two control samples, the observed precision was ≤2% RSD over 10 independent days. In three National Institute of Standards and Technology standard reference materials, Cr, Se, and Mo results were within the certifed limits. The average sample spike recoveries for 10 nutritional products ranged from 93 to 107%. Robustness studies showed a minimal effect from concomitant easily ionized element concentrations. However, the choice of internal standard and matrix matching carbon content were critical to obtaining accurate Se results. All indications are that this method would be a suitable candidate as a global reference method for the determination of these trace elements in nutritional products.
High-Throughput GC/MS and HPLC/MS/MS Techniques for the Multiclass, Multiresidue Determination of 653 Pesticides and Chemical Pollutants in Tea
Authors: Pang Guo-Fang , Fan Chun-Lin , Zhang Feng , Li Yan , Chang Qiao-Ying , Cao Yan-Zhong , Liu Yong-Ming , Li Zeng-Yin , Wang Qun-Jie , Hu Xue-Yan , Liang Ping
Published: February 2020

An effcient and sensitive method has been established for simultaneous determination of 653 pesticides in teas by GC/MS and HPLC/MS/MS. The method involved extraction with acetonitrile followed by cleanup using Cleanert-TPT SPE and subsequent identifcation and quantitation of 490 pesticides by GC/MS and 448 pesticides by HPLC/MS/MS. The LODs for pesticides determined by GC/MS were between 1.0 and 500 µg/kg, and those determined by HPLC/MS/MS were between 0.03 and 4820 µg/kg. At the low fortifcation levels of 0.01–100 µg/kg, the average recoveries of 94% of the pesticides determined by GC/MS were between 60 and 120%, 77% of which had an RSD below 20%. For 91% of pesticides determined by HPLC/MS/MS, the average recoveries were between 60 and 120%, 76% of which had an RSD below 20%. The paper also reports a novel SPE column, Cleanert TPT, which comprised graphitized carbon black (PestiCarb), polyamine silica, and amide polystyrene for purifying the tea samples. The results indicated good repeatiblity and reproducibility.
Discrimination Among Panax Species Using Spectral Fingerprinting
Authors: Chen Pei , Luthriau Devanand , Harringtonohio Peter de B , Harnly James M
Published: February 2020

Spectral fingerprints of samples of three Panax species (P. quinquefolius L., P. ginseng, and P. notoginseng) were acquired using UV, near-infrared (NIR), and MS. With principal component analysis, all three methods allowed visual discrimination among the three species. All three methods were able to discriminate between white and red ginseng, and showed distinctive subgroupings of red ginseng related to root quality (age/size). Analysis of variance was used to evaluate the relative variance arising from the species, run, and analytical uncertainty, and was used to identify the most information-rich portions of the spectrum for NIR and UV. Accurate classification of the three species was obtained by using partial least squares-discriminant analysis and a fuzzy rule-building expert system. Relatively poor accuracy was obtained using soft independent modeling of class analogy when a single component was used.
Chromatographic Method for the Determination of Aflatoxin M1 in Cheese, Yogurt, and Dairy Beverages
Authors: Iha Maria Helena , Barbosa Cynara Baltazar , Favaro Rosa Maria Duarte , Trucksess Mary W
Published: February 2020

The aim of this work was to develop and validate a method to determine aflatoxin M1 (AFM1) in cheese, yogurt, and dairy beverages. The method consisted of aqueous methanol extraction, immunoaffinity column purification and isolation, RPLC separation, and fluorescence detection. The four types of cheese samples were classified according to moisture and fat content. The mean recoveries were 71% for cheese at spiked levels from 100 to 517 ng/kg, and 76% for yogurt and dairy beverages spiked at levels from 66 to 260 ng/kg. The mean RSDs were 5.9% for cheese, and 10% for yogurt and dairy beverages. The LOD was 3 ng/kg and the LOQ was 10 ng/kg for all test commodities. To test the applicability of the developed method, a small survey of the presence of AFM1 in cheese, yogurt, and dairy beverages purchased in Ribeirão Preto-SP, Brazil, was conducted. AFM1 was detected (>3 ng/kg) in all samples. Twenty cheese samples (83%) were contaminated with AFM1 in the range of 13–304 ng/kg. In yogurt and dairy beverages, the contamination was lower (13–22 ng/kg) in five samples (42%). The results indicated that the method is adequate for the determination of AFM1 in these four types of cheese, as well as in yogurt and dairy beverages.