bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Hydrastine and Berberine in Goldenseal Raw Materials, Extracts, and Dietary Supplements by High-Performance Liquid Chromatography with UV: Collaborative Study
Authors: Brown Paula N , Roman Mark C ,   Collaborators:, Chang C , Jin C , Kuriyedath R , Lidstone S , Ly L , Ma Y-C , Sigmund P , Smith R , Wijewickreme N 
Published: February 2020

Abstract
A multilaboratory collaborative study was conducted on a high-performance liquid chromatographic (HPLC) method utilizing UV detection, previously validated using AOAC single-laboratory validation guidelines for determination of hydrastine and berberine in goldenseal (Hydrastis canadensis L.) raw materials, extracts, and dietary supplements at levels ranging from 0.4 to 6 (w/w). Nine collaborating laboratories determined the hydrastine and berberine content in 8 blind samples. Sample materials included powdered botanical raw materials, whole root material, and 4 finished product dietary supplements containing either goldenseal powdered root material or extract. The materials were extracted with an acidified water and acetonitrile solution. HPLC analyses of the extracts were performed on a C18 column using UV detection at 230 nm. Results for powdered root material and capsule products ranged from about 0.2 (w/w) for each alkaloid to about 4 (w/w) for each alkaloid. Liquid tincture results were approximately 40005000 g/mL for each alkaloid. Reproducibility relative standard deviations (RSDR) for hydrastine ranged from 2.68 to 6.65, with HorRat values ranging from 0.77 to 1.89. RSDR for berberine ranged from 5.66 to 7.68, with HorRat values ranging from 1.32 to 2.12. All finished products containing goldenseal extract yielded HorRat values &lt;2.0. Based on these results, the method is recommended for Official First Action for determination of hydrastine and berberine in goldenseal raw materials and dietary supplement finished products containing powdered goldenseal and goldenseal extract.
Determination of Moisture and Fat in Meats by Microwave and Nuclear Magnetic Resonance Analysis: Collaborative Study
Authors: Leffler Timothy P , Moser Cindy R , McManus Bobbie J , Urh John J , Keeton Jimmy T , Claflin Amy ,   Collaborators:, Adkins K , Claflin A , Davis C , Elliot J , Goin P , Horn C , Humphries J , Ketteler K , Perez P , Steiner G 
Published: February 2020

Abstract
Ten laboratories participated in a collaborative study to determine the total moisture and fat in raw and processed meat products by microwave drying and nuclear magnetic resonance (NMR) spectroscopy. Meat products were prepared following the AOAC Method and analyzed using CEM Corp.'s SMART Trac Moisture and Fat Analysis system. SMART Trac provides moisture results by measuring the weight loss on drying by microwave energy. The dried sample is then analyzed by NMR spectrometry for fat content. Moisture and fat results are displayed and reported by the SMART Trac as a percentage (g/100 g). Microwave drying is an AOAC-approved reference method (Method 985.14), Moisture in Meat and Poultry Products. NMR spectrometry is a secondary technique used to determine the concentration of various constituents in biological, organic, or chemical samples. The study design was based on Youden's matched pair principle for collaborative tests. For the purposes of this study, 10 laboratories each tested 10 Youden matched pairs, for a total of 20 samples. The study samples represented a range of products processed daily in plant operations. Included were raw meat samples (beef, pork, chicken, and turkey) as well as processed meats (beef hot dog, pork sausage, and ham). The total moisture content of the undiluted samples, as received for the purposes of this study, was determined by AOAC Method 950.46 and ranged from 54.03 to 74.99. The total fat content of the undiluted samples was determined by AOAC Method 960.39 and ranged from 1.00 to 29.79. Statistical analysis of study results for total moisture yielded a relative standard deviation for repeatability (RSDr) range of 0.14 to 0.95 and a relative standard deviation for reproducibility (RSDR) range of 0.26 to 0.95. Statistical analysis for total fat yielded similar RSDr and RSDR range of 0.74 to 4.08. Results for turkey had higher RSDr and RSDR values, both at 12.6, due to low fat content and possibly to the separation of the samples observed by some of the collaborators. Results demonstrate that microwave drying with NMR is a rapid, practical method providing results equivalent to AOAC Methods 950.46 (Forced Air Oven Drying) and 960.39 (Soxhlet Ether Extraction) in raw and processed meat products.
Modification of AOAC Method 973.31 for Determination of Nitrite in Cured Meats
Authors: Mohamed Ashraf A , Mubarak Ahmed T , Fawy Khaled F , El-Shahat Mohamed F 
Published: February 2020

Abstract
A modification of AOAC Method 973.31 is proposed to improve the extraction efficiency of nitrite from cured meat samples and its subsequent quantification based on the diazotization-coupling reaction of sulfanilamide with N-1-naphthyl)ethylenediamine dihydrochloride (NED). The various experimental parameters were thoroughly investigated. A 5 g meat sample was mixed with 400 mL water; the pH of the mixture was adjusted to 5.5 0.3 and allowed to stand for 2 h on a water bath at 80&lt;sup/&gt;C, with occasional shaking for the complete extraction of nitrite. After quantitative filtration, an aliquot was mixed with chloroaceticchloroacetate buffer, pH 1.80 0.05, sulfanilamide, and NED, and the absorbance of the resulting azodye was recorded at 540 nm against water as a reference. Following the recommended procedure, a linear calibration graph was obtained for up to 0.8 g/mL NO2&lt;sup/&gt;, with a correlation coefficient of 0.9996 and a detection limit (based on the 3 Sb-criterion) of 5.6 ng/mL NO2&lt;sup/&gt;. The proposed method was conveniently applied to various cured meat samples and was validated by comparison with the original AOAC method and by recovery experiments that gave quantitative results (9498) with convenient reproducibility. Statistical analysis of the analytical data could not detect any systematic error and revealed the high accuracy and precision of the proposed method.
Determination of Copper in Water and Plant Samples by Flame Atomic Absorption Spectrometry After Preconcentration on Octadecyl Silica Membrane Disks Modified with a Recently Synthesized Schiff's Base
Authors: Shamspur Tayebeh , Mostafavi Ali , Sheikhshoaie Iran 
Published: February 2020

Abstract
A simple, selective, reliable, and sensitive method for the determination of trace amounts of Cu2+ ions in aqueous samples is proposed. The Cu2+ ions are adsorbed quantitatively during the passage of aqueous samples through an octadecyl (C18) silica membrane disk modified by a symmetrical tetradentate Schiff base ligand, N,N'-bis(4-phenylazo salicylaldimine) 3-chloro-1,2-phenylenediamine (H2L). The retained Cu2+ ions were then stripped from the disk by elution with the minimal amount of nitric acid solution and determined by flame atomic absorption spectrometry. Various parameters, such as the effect of pH, flow rate, type and amount of eluent, and the effects of various cationic interferences on the recovery of ions were studied. The proposed method permitted large enrichment factors (about 550 and higher). The limit of detection of the method was 1.5 102 g/L. The use of the same disk modified with 6 mg H2L for at least 30 times showed no change in the recovery of Cu2+ ions. The accuracy of the method was confirmed by determination of Cu2+ ions in standard samples [National Institute of Environmental Studies (NIES) No. 2 and Nippon Keikinzoku Kogyo (NKK) No. 920]. The results demonstrated good agreement with certified values.
Evaluation of a Method for Determining Concentrations of Isoeugenol, an AQUI-S Residue, in Fillet Tissue from Freshwater Fish Species
Authors: Meinertz Jeffery R , Schreier Theresa M , Bernardy Jeffry A 
Published: February 2020

Abstract
AQUI-S is a fish anesthetic/sedative that is approved for use in a number of countries throughout the world and has the potential for use in the United States. The active ingredient in AQUI-S is isoeugenol. A method for determining isoeugenol concentrations in edible fillet tissue is needed for regulatory purposes, including surveillance and potential use in studies fulfilling human food safety data requirements if U.S. Food and Drug Administration approval is pursued. A method was developed and evaluated for determining isoeugenol concentrations in fillet tissue using relatively common procedures and equipment. The method produced accurate and precise results with fillet tissue from 10 freshwater fish species. The percentage of isoeugenol recovered from samples fortified with isoeugenol at nominal concentrations of 1, 50, and 100 g/g for all species was always &gt;80 and &lt;97. Within-day precision for samples fortified at those same concentrations was 10, and day-to-day precision was 4.0. Method precision with fillet tissue containing biologically incurred isoeugenol was 8.1. There were no or minimal chromatographic interferences in control fillet tissue extracts from 9 of the 10 species. The method detection limits for all but one species ranged from 0.004 to 0.014 g/g, and the quantitation limits ranged from 0.012 to 0.048 g/g.
Available Lysine in Foods: A Brief Historical Overview
Authors: Moughan Paul J , Rutherfurd Shane M 
Published: February 2020

Abstract
A brief historical overview is presented on the development of the science addressing lysine bioavailability in foods. Early observations that dietary protein utilization did not always correlate with gross amino acid composition led to an understanding that the amino acid lysine, in particular, can be easily damaged during food processing. Conventional amino acid analysis, involving a strong acid hydrolysis step, can lead to a significant degree of overestimation of lysine in processed foods. More recently, it has been found that not only food lysine content values but also estimates of lysine digestibility and digestible lysine contents may be erroneous. Estimates of absorbed (true ileal digestible) reactive lysine are accurate measures of available lysine. Technically, bioassays such as the slope-ratio assay determine utilized rather than available lysine.
Lunasin: A Novel Cancer Preventive Seed Peptide that Modifies Chromatin
Authors: de Lumen Ben O 
Published: February 2020

Abstract
Lunasin is a novel cancer preventive peptide whose efficacy against chemical carcinogens and oncogenes has been demonstrated in mammalian cells and a skin cancer mouse model. In contrast, constitutive expression of the lunasin gene in mammalian cells leads to arrest of cell division and cell death. Isolated and characterized in soy, lunasin peptide is also documented in barley and wheat and is predicted to be present in many more seeds because of its possible role in seed development. Initial studies show that lunasin is bioavailable in mice when orally ingested. Lunasin internalizes into mammalian cells within minutes of exogenous application, and localizes in the nucleus after 18 h. It inhibits acetylation of core histones in mammalian cells but does not affect the growth rate of normal and established cancer cell lines. An epigenetic mechanism of action is proposed whereby lunasin selectively kills cells being transformed or newly transformed cells by binding to deacetylated core histones exposed by the transformation event, disrupting the dynamics of histone acetylationdeacetylation.
Biopharming to Increase Bioactive Peptides in Rice Seed
Authors: Yang Lijun , Wakasa Yuhya , Takaiwa Fumio 
Published: February 2020

Abstract
The production of high-value pharmaceutical proteins and peptides in transgenic plants is an attractive and economically feasible alternative to conventional mammalian cell, yeast, and bacterial systems. In contrast to vegetative tissues, rice seeds allow higher accumulation of recombinant proteins and long-term stable storage. Rice is not only consumed as a staple food by a majority of the world's population, but is also used as a model monocot for biotechnological manipulation. Daily oral consumption of transgenic rice seeds that accumulate high concentrations of food-derived or synthetic bioactive peptides can be expected to provide a safe, reliable, and consistent oral delivery system that would contribute to the promotion of human health care.
Determination of Cyclamate in Foods by Ultraperformance Liquid Chromatography/Tandem Mass Spectrometry
Authors: Sheridan Robert , King Thomas 
Published: February 2020

Abstract
A highly sensitive and selective method that requires minimal sample preparation was developed for the confirmation and quantitation of cyclamate in a variety of foods by high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). Sample preparation consisted of homogenization followed by extraction and dilution of cyclamate with water. HPLC separation was achieved using a bridged ethyl hybrid C18 high-pressure column with a mobile phase consisting of 0.15 acetic acid and methanol. Under electrospray ionization negative conditions, quantitation was achieved by monitoring the fragment m/z 79.7 while also collecting parent ion m/z 177.9. Two food matrixes, diet soda and jelly, were subjected to a validation procedure in order to evaluate the applicability of the method. The cyclamate limit of detection for both matrixes was determined to be 0.050 g/g with a limit of quantitation of 0.150 g/g. The correlation coefficient of the calibration curves was &gt;0.9998 from 0.0005 to 0.100 g/mL. The method has been used for the determination of cyclamate in several foods and the results are presented.
Quantitative Determination of Dimethylaminoethanol in Cosmetic Formulations by Nuclear Magnetic Resonance Spectroscopy
Authors: Andradebatista Ivani Aparecida Soares De , Gonçalves Maria Inês De Almeida , Singh Anil Kumar , Hackmann Erika Rosamaria Kedor , Santoro Andmaria Inês Rochamiritello 
Published: February 2020

Abstract
A nuclear magnetic resonance (NMR) spectroscopic method was validated for the quantitative determination of dimethylaminoethanol (DMAE) in cosmetic formulations. The linearity in the range from 0.5000 to 1.5000 g (DMAE salt/mass maleic acid) presents a correlation coefficient &gt;0.99 for all DMAE salts. The repeatability (intraday), expressed as relative standard deviation, ranged from 1.08 to 1.44 for samples and 1.31 to 1.88 for raw materials. The detection limit and quantitation limit were 0.0017 and 0.0051 g for DMAE, 0.0018 and 0.0054 g for DMAE bitartrate, and 0.0023 and 0.0071 g for DMAE acetamidobenzoate, respectively. The proposed method is simple, precise, and accurate and can be used in the quality control of raw materials and cosmetic gels containing these compounds as active substances.
Determination of Norfloxacin and Enrofloxacin by Solid-Phase Microextraction/High-Performance Liquid Chromatography
Authors: Kumar Ashwini , Dhingra Gaurav , Kumar malik Ashok , Tewary Dhananjay K 
Published: February 2020

Abstract
A solid-phase microextraction (SPME) method followed by separation with high-performance liquid chromatography and subsequent UV detection was developed for the determination of norfloxacin and enrofloxacin. The simple and sensitive preconcentration technique uses 280 nm wavelength in mobile phase of citrate buffer (0.01 M), pH 3.8, prepared in water (A) and acetonitrile (B), with composition of the mobile phase A:B, 40:60, at a flow rate of 1.0 mL/min. A C18 reversed-phase analytical column (5 m) was selected as separation medium for the technique. To obtain optimum extraction efficiency, several parameters relating to SPME were investigated. The method was linear over the range of 10100 ng/mL for norfloxacin and enrofloxacin with a correlation coefficient (R2) value of 0.9972 and 0.9980 for norfloxacin and enrofloxacin, respectively. Using the SPME method, the detection limits (signal-to-noise ratio 3) are 0.17 and 0.12 ng/mL for norfloxacin and enrofloxacin, respectively.
Sensitive Mercury Speciation by Reversed-Phase Column High-Performance Liquid Chromatography with UV-Visible Detection After Solid-Phase Extraction Using 6-Mercaptopurine and Dithizone
Authors: Hashemi-Moghaddam Hamid , Saber-Tehrani Mohamad 
Published: February 2020

Abstract
A highly selective and sensitive method was developed for preconcentration of inorganic and organic mercury compounds followed by reversed-phase column high-performance liquid chromatography (RP-HPLC) with UV-visible detection. The method was based on the reaction of mercury with 6-mercaptopurine and solid-phase extraction (SPE) of the complex on an octadecylsilane (C18) cartridge. The complex was then treated with ammoniacal dithizone solution, and the complexes of inorganic and organic mercury with dithizone were eluted by methanol. The speciation analysis of methylmercury (MeHg), phenylmercury (PhHg), and inorganic Hg (II) was carried out by RP-HPLC. Some experimental variables that influence the SPE and derivatization, such as pH, chelating and derivatizing agent concentration, and surfactant addition, were investigated. The calibration graphs of MeHg, PhHg, and Hg (II) were linear [correlation coefficient (r) &gt; 0.999] from the detection limits (0.12, 0.16, and 0.14 ng) to 8.5, 6.0, and 6.7 ng Hg, respectively. By applying the SPE procedure, a 100-fold concentration of the sample was obtained. The procedure was applied to sea water and tuna fish samples. The method's accuracy was investigated by using tuna fish certified reference material BCR 464 and by spiking the samples with different amounts of MeHg, PhHg, and Hg (II). The average recoveries of MeHg, PhHg, and Hg (II) from spiked samples (0.12.0 g/L Hg) were 96 4, 98 3, and 104 4, respectively.
Column High-Performance Liquid Chromatographic Method for the Simultaneous Determination of Rosiglitazone and Metformin in a Pharmaceutical Preparation
Authors: Ali Azzam R , Duraidi Ibrahim I , Saket Munib M , Abu-Nameh Eyad S M 
Published: February 2020

Abstract
An efficient, sensitive, and simple method was developed for the simultaneous determination of rosiglitazone and metformin hydrochloride in a combination tablet dosage form by column high-performance liquid chromatography. The mobile phase used was ammonium dihydrogen phosphate adjusted to pH 5.25 with sodium hydroxide. The limits of detection and quantitation were in the range of 0.51.6 g/mL, respectively, for metformin hydrochloride, and 0.002010.0067 g/mL, respectively, for rosiglitazone. The linearity was studied in the concentration range of 0.120.31 g/mL for rosiglitazone and 30.676.7 g/mL for metformin hydrochloride. The recovered amounts of metformin hydrochloride and rosiglitazone were 100103.8 and 101103.7, respectively.
Refinement and Extension of AOAC Method 2005.06 to Include Additional Toxins in Mussels: Single-Laboratory Validation
Authors: Turner Andrew D , Norton Deirdre M , Hatfield Robert G , Morris Steven , Reese Allan R , Algoet Myriam , Lees David N 
Published: February 2020

Abstract
A single-laboratory validation study was undertaken for the analysis of paralytic shellfish poisoning (PSP) toxins in common mussels, extending AOAC Official Method 2005.06 to include the additional toxins dcNEO and dcGTX2,3. The method was refined to improve toxin oxidation product stability, analytical sensitivity of N-hydroxylated toxins, and throughput. Validation was performed to characterize the method for selectivity, sensitivity, linearity, precision, repeatability, recovery, ruggedness, and uncertainty. Parallel testing of naturally contaminated mussels enabled comparison of sample toxicities obtained using mouse bioassay (MBA) and high-performance liquid chromatographic (HPLC) methodologies. Performance characteristics of the method are reported for all commercially available certified reference toxins. Results from the MBA and HPLC methods were well correlated, and the analytical method has been instigated as the sole monitoring tool for UK official control surveillance of PSP toxins in common mussels.
Determination of Nine Intense Sweeteners in Foodstuffs by High-Performance Liquid Chromatography and Evaporative Light-Scattering Detection: Interlaboratory Study
Authors: Buchgraber Manuela , Wasik Andrzej ,   Collaborators:, Casal S , Dubois A , Gutsche B , Hanewinkel-Meshkini S , Martin D , Naas D 
Published: February 2020

Abstract
An interlaboratory trial was conducted to validate an analytical method based on high-performance liquid chromatographic analysis with evaporative light-scattering detection for the simultaneous determination of 9 intense sweeteners, i.e., acesulfame-K, alitame, aspartame, cyclamic acid, dulcin, neotame, neohesperidine dihydrochalcone, saccharin, and sucralose in carbonated and noncarbonated soft drinks and canned or bottled fruits. Seven laboratories participated in the validation study. The majority of the samples fortified with levels close to the limit of quantification had relative standard deviation for reproducibility (RSDR) values &lt;15. In most cases, the recovery rates ranged between 90 and 105, demonstrating satisfactory performance of the method. For samples fortified at levels comparable to the prescribed legal limits stipulated in the current European Union legislation, the method produces acceptably accurate, repeatable, and reproducible results. Trueness, expressed in terms of recovery rates, was demonstrated in most cases by values ranging from 90 to 108. Comparability of results obtained by individual testing laboratories was good (RSDR values &lt;10) for the majority of results. Moreover, HorRat values of &lt;1.1 suggested good performance of the method for all sweeteners and matrixes tested.
Development of a Carbon Paste Electrode Containing Benzo-15-Crown-5 for Trace Determination of the Uranyl Ion by Using a Voltammetric Technique
Authors: Agrahari Sunil K , Kumar Sangita D , Srivastava Ashwini K 
Published: February 2020

Abstract
The interaction of macrocyclic compounds like crown ethers and UO22+ has been studied by electrochemical methods. A modified carbon paste electrode incorporating benzo-15-crown-5 (B15C5) was used to evaluate the electron transfer reaction of UO22+ by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Electrochemical impedance studies showed that charge transfer resistance was less for the B15C5-modified electrode than for the plain carbon paste electrode (PCPE). On the basis of these observations, a UO22+-sensitive crown ether chemically modified electrode (CME) for trace analysis was fabricated and investigated in aqueous solutions. It was found that a 5 B15C5CME for UO22+ showed a better voltammetric response than did the PCPE. UO22+ could be quantified at sub-μg/mL levels by differential pulse voltammetry with a detection limit of 0.03 μg/mL. By differential pulse adsorptive stripping voltammetry, UO22+ could be quantified in the working range of 0.002-0.2 μg/mL, with a detection limit of 1.1 μg/L. Simultaneous determination of UO22+, Pb2+, and Cd2+ was possible. The method was successfully applied to the determination of UO22+ in synthetic, as well as real, samples; the results were found to be comparable to those obtained by inductively coupled plasma-atomic emission spectroscopy.