bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of Stigmasterol Oxidation by Antioxidants in Purified Sunflower Oil
Authors: Rudzińska Magdalena , Korczak Józef , Gramza Anna , Wąsowicz Erwin , Dutta Paresh C 
Published: February 2020

Abstract
A study was conducted to analyze the effect of the antioxidants butylated hydroxytoluene, α-tocopherol, ethanolic extracts of rosemary, and green tea on stigmasterol resistance against degradation and formation of its oxidation products in purified triacylglycerols (TAG) from sunflower oil. The content of stigmasterol and its oxidation products 7α-and 7β-hydroxy, α-and β-epoxy, triol, and 7-ketostigmasterol were determined during incubation at 60°C for 3, 6, and 9 days. In addition, peroxide value and fatty acid composition were also determined in the samples. Correlation between the levels of the accumulated stigmasterol oxides and peroxide value of the TAG with antioxidants during incubation was significant only for rosemary extract (R = 0.6799, p &lt; 0.05). The lack of correlation precludes the use of peroxide values to determine the level of sterol oxidation products in the used model system. Correlation between stigmasterol content and the level of stigmasterol oxides was significant for all samples (R = 0.8874, p &lt; 0.05). The total increase of the stigmasterol oxidation products was the lowest in samples with α-tocopherol, but the content of stigmasterol-triol increased the most in this sample. In all the analyzed samples, α-epoxy-stigmasterol was formed in the highest amounts among the analyzed stigmasterol oxidation products.
Overview of Infrared Methodologies for trans Fat Determination
Authors: Mossoba Magdi M , Yurawecz Martin P , Delmonte Pierluigi , Kramer John K G 
Published: February 2020

Abstract
trans Fatty acids are present in a variety of foods like dairy products, but the major sources are products that contain commercially hydrogenated fats. Some studies have shown that trans fatty acids elevate levels of serum low-density lipoprotein (LDL)-cholesterol and lower high-density lipoprotein (HDL)-cholesterol. The quantitation and identification of trans fatty acid isomers is difficult because of the wide range of positional monoene, diene, and triene fatty acid isomers present in hydrogenated oils. This is complicated by the cis positional isomers that are also present, as well as the lack of commercial chromatographic standards for many fatty acid isomers. In this review, infrared methodologies for the determination of total trans fat are presented. Using an attenuated total reflection (ATR) infrared cell, a novel Fourier transform infrared (FTIR) spectroscopic method that was developed for the rapid (5 min) quantitation of the total trans fatty acid levels in neat (without solvent) fats and oils measured as triacylglycerols (TAG) is discussed. TAG required no derivatization, but had to be melted prior to measurement. The lower limit of trans quantitation was 5% of total fat. The precision of this ATR method was found to be superior to that of transmission infrared official methods. Accuracy was enhanced by generating a symmetric absorption trans infrared band at 966 cm-1 on a horizontal background. This was achieved by “ratioing” the single-beam spectrum of the trans-containing fat or oil against that of a reference oil or standard having only cis double bonds. Attempts to apply this ATR-FTIR method to food matrixes with low trans fat and/or low total fat content were not satisfactory due to interfering infrared absorptions in the trans region. To overcome this interference, the method was modified by applying the standard addition technique to the ATR-FTIR determination. The modified procedure required more time, but eliminated any adverse impact on accuracy arising from interfering minor food components having absorption bands near 966 cm−1.
Biosensor Analysis of β-Lactams in Milk: Comparison with Microbiological, Immunological, and Receptor-Based Screening Methods
Authors: Gustavsson Eva , Sternesjö Åse 
Published: February 2020

Abstract
Two recently developed surface plasmon resonance biosensor assays for detection of β-lactams in milk were used to screen raw producer milk samples. Both assays use a β-lactam receptor protein with carboxypeptidase activity for detection. The results of the biosensor assays were compared with those of various commercial screening tests, i.e., the Delvotest SP, Penzym S, Beta-STAR, SNAP, and Parallux. The results of the 2 biosensor assays showed good agreement with those of the other screening tests. Of 195 analyzed milk samples, the results of only 5 samples differed between the assays. Additionally, 30 milk samples with both negative and positive results in the screening assays were analyzed by liquid chromatography for identification and quantification of any β-lactam residues. All screening tests showed 0% false-negative results with 15 incurred samples containing between 4.0 and 268 μg/kg penicillin G. The biosensor assays showed 27% positive results (false violatives) with 15 producer milk samples containing penicillin G concentrations between 0 and 3.6 μg/kg, i.e., below maximum residue limit. This figure varied between 27 and 53% for the other screening tests.
Suitability of Real-Time Quantitative Polymerase Chain Reaction and Enzyme-Linked Immunosorbent Assay for cry9C Detection in Mexican Corn Tortillas: Fate of DNA and Protein After Alkaline Cooking
Authors: Quirasco Maricarmen , Schoel Bernd , Plasencia Javier , Fagan John , Galvez Amanda 
Published: February 2020

Abstract
Alkaline-cooked corn, called nixtamal, is the basis for many traditional corn products such as tortillas, chips, and taco shells that are used widely in Mexico and Central America and in the preparation of snack foods that are consumed globally. To assess the effects of alkaline and thermal treatments on the detectability of DNA and protein for the presence of genetically modified sequences, various nixtamalized products were prepared from blends of conventional white corn containing 0.1, 1.0, and 10% transgenic corn (event CBH 351, StarLink™). Real-time quantitative polymerase chain reactions (RTQ–PCR) and immunoassays were used to determine the cry9C gene and protein, respectively, in unprocessed corn kernels, freshly prepared alkaline-cooked and ground corn (masa), masa flour, tortillas prepared from masa by heat treatment, chips prepared from damp masa dough by deep frying, and from tortillas processed at high (200°C) and low temperatures (70°C). In spite of progressive degradation of genomic DNA during processing, RTQ–PCR genetic analysis allowed detection and quantification of the cry9C gene in all products prepared from 10, 1, and 0.1% StarLink corn, except deep-fried chips containing 0.1% StarLink. Enzyme-linked immunosorbent assays readily detected &lt;1ppm cry9C protein in all blends of unprocessed corn (10, 1, and 0.1% StarLink) as well as in nonfried tortilla and masa products. This technique was not suitable for thermally treated nixtamalized products containing &lt;1% transgenic corn.
Resistant Starches and Health
Authors: Kendall Cyril W C , Emam Azadeh , Augustin Livia S A , Jenkins David J A 
Published: February 2020

Abstract
It was initially hypothesized that resistant starches, i.e., starch that enters the colon, would have protective effects on chronic colonic diseases, including reduction of colon cancer risk and in the treatment of ulcerative colitis. Recent studies have confirmed the ability of resistant starch to increase fecal bulk, increase the molar ratio of butyrate in relation to other short-chain fatty acids, and dilute fecal bile acids. However the ability of resistant starch to reduce luminal concentrations of compounds that are damaging to the colonic mucosa, including fecal ammonia, phenols, and N-nitroso compounds, still requires clear demonstration. As such, the effectiveness of resistant starch in preventing or treating colonic diseases remains to be assessed. Nevertheless, there is a fraction of what has been termed resistant (RS1) starch, which enters the colon and acts as slowly digested or lente carbohydrate in the small intestine. Foods in this class are low glycemic index and have been shown to reduce the risk of chronic disease. They have been associated with systemic physiological effects such as reduced postprandial insulin levels and higher HDL cholesterol levels. Consumption of low glycemic index foods has been shown to be related to reductions in risk of coronary heart disease and Type 2 diabetes. Type 2 diabetes has in turn been related to a higher risk of colon cancer. If carbohydrates have a protective role in colon cancer prevention this may lie partly in the systemic effects of low glycemic index foods. The colonic advantages of different carbohydrates, varying in their glycemic index and resistant starch content, therefore, remain to be determined. However, as recent positive research findings continue to mount, there is reason for optimism over the possible health advantages of those resistant starches, which are slowly digested in the small intestine.
Sample Preparation and Determination of Ginkgo Terpene Trilactones in Selected Beverage, Snack, and Dietary Supplement Products by Liquid Chromatography with Evaporative Light-Scattering Detection
Authors: Lang Qingyong , Wai Chien M , Ang Catharina Y W , Cui Yanyan , Heinze Thomas M , Mattia Antonia , Dinovi Michael 
Published: February 2020

Abstract
Ginkgo biloba leaf extract has been widely used in dietary supplements and more recently in some foods and beverages. Sample preparation procedures for determination of ginkgo terpene trilactones (including bilobalide and ginkgolides A, B, C, and J) in various sample matrixes were developed in this study. Ginkgo leaves and capsules were extracted with 5% KH2PO4 aqueous solution under sonication. Tea bags were extracted with boiling water, whereas drink samples were taken directly from the bottles. After filtration and the addition of NaCl to approximately 30% (w/v), the terpene trilactones in aqueous solutions were quantitatively extracted with ethyl acetate–tetrahydrofuran (4 + 1, v/v). Puff samples (a cereal-based fried snack item) were first defatted by using hexane or by using supercritical fluid extraction and then extracting under sonication with methanol–acetic acid (99 + 1, v/v). After evaporation of the organic phase, the terpene trilactones were redissolved in methanol and determined on a C18 reversed-phase column by liquid chromatography (LC) with evaporative light-scattering detection. The method of standard additions and gas chromatography with flame ionization detection were used for method validation. For most samples, the relative standard deviation was &lt;10%. The identities of target compounds in ginkgo leaves and drink samples were confirmed by LC/electrospray ionization–tandem mass spectrometry.
The Modular Analytical Procedure and Validation Approach and the Units of Measurement for Genetically Modified Materials in Foods and Feeds
Authors: Holst-Jensen Arne , Berdal Knut G 
Published: February 2020

Abstract
Food and feed analysts are confronted with a number of common problems, irrespective of the analytical target. The analytical procedure can be described as a series of successive steps: sampling, sample processing, analyte extraction, and ending, finally, in interpretation of an analytical result produced with, e.g., real-time polymerase chain reaction. The final analytical result is dependent on proper method selection and execution and is only valid if valid methods (modules) are used throughout the analytical procedure. The final step is easy to validate—the measurement uncertainty added from this step is relatively limited and can be estimated with a high degree of precision. In contrast, the front-end sampling and processing steps have not evolved much, and the corresponding methods are rarely or never experimentally validated according to internationally harmonized protocols. In this paper, we outlined a strategy for modular validation of the entire analytical procedure, using an upstream validation approach, illustrated with methods for genetically modified materials that may partially apply also to other areas of food and feed analyses. We have also discussed some implications and consequences of this approach in relation to reference materials, measurement units, and thresholds for labelling and enforcement, and for application of the validated methods (modules) in routine food and feed analysis.
Evaluation of Sampling Plans to Detect Cry9C Protein in Corn Flour and Meal
Authors: Whitaker Thomas B , Trucksess Mary W , Giesbrecht Francis G , Slate Andrew B , Thomas Francis S 
Published: February 2020

Abstract
StarLink is a genetically modified corn that produces an insecticidal protein, Cry9C. Studies were conducted to determine the variability and Cry9C distribution among sample test results when Cry9C protein was estimated in a bulk lot of corn flour and meal. Emphasis was placed on measuring sampling and analytical variances associated with each step of the test procedure used to measure Cry9C in corn flour and meal. Two commercially available enzyme-linked immunosorbent assay kits were used: one for the determination of Cry9C protein concentration and the other for % StarLink seed. The sampling and analytical variances associated with each step of the Cry9C test procedures were determined for flour and meal. Variances were found to be functions of Cry9C concentration, and regression equations were developed to describe the relationships. Because of the larger particle size, sampling variability associated with cornmeal was about double that for corn flour. For cornmeal, the sampling variance accounted for 92.6% of the total testing variability. The observed sampling and analytical distributions were compared with the Normal distribution. In almost all comparisons, the null hypothesis that the Cry9C protein values were sampled from a Normal distribution could not be rejected at 95% confidence limits. The Normal distribution and the variance estimates were used to evaluate the performance of several Cry9C protein sampling plans for corn flour and meal. Operating characteristic curves were developed and used to demonstrate the effect of increasing sample size on reducing false positives (seller's risk) and false negatives (buyer's risk).
Solid-Phase Extraction and Cleanup Procedures for Determination of Acrylamide in Fried Potato Products by Liquid Chromatography/Mass Spectrometry
Authors: Young Michael S , Jenkins Kevin M , Mallet Claude R 
Published: February 2020

Abstract
In response to recent discoveries of acrylamide in heated foods, a solid-phase extraction and cleanup protocol was developed for the determination of acrylamide in fried or baked potato samples by liquid chromatography/mass spectrometry (LC/MS). The analyte was extracted from the matrix by using 2M NaCl, and an aliquot of the initial extract was loaded onto a reversed-phase cartridge. After the analyte was eluted from the cartridge, the eluate was cleaned up on a mixed-mode cation-exchange cartridge. The eluate was then evaporated, and the residue was reconstituted in mobile phase before LC/MS analysis. Recoveries, based on the recovery of an added internal standard, ranged from 96 to 101% with relative standard deviations (RSDs) of 5–11%. The response was linear for a concentration range of 100–2000 ng/g with a coefficient of determination (R2)of 0.992 (n = 25). An interday study showed good accuracy and precision of the method over a 3-day period with a recovery of 98% and an RSD of 9.5% (n = 15). The analyses of 6 potato chip samples showed concentrations of incurred acrylamide ranging from 260 to 1500 ng/g.
Determination of Thallium in Potassium Chloride and Electrolyte Replenishers by Electrothermal Atomic Absorption Spectrometry
Authors: Nukatsuka Isoshi , Horiguchi Ryo , Seitoh Hiroyuki , Ohzeki Kunio , Miyashita Fumihide 
Published: February 2020

Abstract
Thallium in potassium chloride and electrolyte replenishers was determined by electrothermal atomic absorption spectrometry (ETAAS) with direct injection of a resin suspension. Thallium(III) was extracted on fine particles of a cellulose nitrate resin (CNR) from dilute HCl (pH 1.6) in the presence of ammonium pyrrolidine-1- carbodithioate. The CNR particles were collected on a membrane filter by filtration under suction, suspended in 1.0 mL 10mM HNO3, and then delivered directly to ETAAS as the suspension. The effects of chloride ions were thoroughly investigated. The results showed that the addition of 0.5mM NaCl to the suspension (10mM HNO3) was recommended, after CNR and a membrane filter holding the CNR were washed thoroughly with 0.025M HCl, to eliminate interference from chloride ions. No chemical modifier was required. Extraction from the solution containing up to 2M chloride ion was allowable. The proposed method gave a concentration factor of 50 for a 50 mL sample volume. The detection limit (3σ, n = 5) was 1 ng (20 pg/mL). The relative standard deviation was 4.9% (n = 5) at 30 ng level of thallium. The content of thallium in potassium chloride was 15.7–32.8 ng/g, and in electrolyte replenishers was 0.18–4.16 ng/mL.
Ultraviolet Derivatization of Steroidal Saponin in Garlic and Commercial Garlic Products as p-Nitrobenzoate for Liquid Chromatographic Determination
Authors: Mochizuki Emiko , Yamamoto Takao , Mimaki Yoshihiro , Sashida Yutaka 
Published: February 2020

Abstract
A method is described for determination of the steroidal saponin, eruboside B, originating in garlic and garlic products as the p-nitrobenzoyl chloride (PNBC) derivative by reversed-phase liquid chromatography (with ultraviolet detection at 260 nm. Proto-eruboside B was extracted from garlic (Allium sativum L.); subjected to solid-phase extraction (SPE) with a C18 cartridge, Florisil column chromatography, and silica gel column chromatography; and then enzymatically converted to eruboside B, which was applied as an external standard. Steroidal saponins in garlic and commercial garlic products were extracted with methanol and purified by SPE cartridges, followed by enzymatic treatment. A frostanol saponin such as proto-eruboside B is enzymatically transformed to a spirostanol saponin, eruboside B. After the derivatization with PNBC, the saponin derivative was chromatographed on a C8 column with a gradient elution of (A) 80% aqueous acetonitrile and (B) 100% acetonitrile. The detection limit of the developed method was 1 μg/g for the samples. The method was applied to the analysis of garlic and and garlic health food products available in Japan.
Method for the Determination of β-Carotene in Supplements and Raw Materials by Reversed-Phase Liquid Chromatography: Single Laboratory Validation
Authors: Schierle Joseph , Pietsch Bernd , Ceresa Alan , Fizet Christian , Waysek Edward H 
Published: February 2020

Abstract
A single laboratory validation (SLV) study was conducted for a liquid chromatography (LC) method for the determination of total and all-trans-β-carotene in a variety of dietary supplements, including multivitamin tablets, softgels, capsules, and beadlet raw materials. Extraction variants were developed for the different types of supplements tested based upon the supplement type and level of β-carotene. Water dispersible formulations such as powders, emulsions, tablets, and capsules were enzymatically digested with protease and extracted with dichloromethane–ethanol. Oily suspensions were directly dissolved in dichloromethane–ethanol. After appropriate dilution or concentration, the extracts were chromatographed by using either a reversed-phase C18 column or, in products containing high amounts of α-carotene, a reversed-phase C30 column. The LC systems provided linear responses in the range of 0.1–50 μg β-carotene/mL. The main geometrical isomers of β-carotene (all-trans, 9-cis, 13-cis, and 15-cis) were well separated from each other and from other carotenoids such as α-carotene, cryptoxanthin, lutein, lycopene, and zeaxanthin. Duplicate determinations of total β-carotene performed by 2 technicians in 8 different test materials on 5 different days resulted in relative standard deviations of 1.2–4.4%. Recoveries determined for supplements and beadlet raw material spiked with β-carotene levels of 10 μg to 100 mg/test portion and 0.2–40%, respectively, ranged from 97.5 to 102.1%. On the basis of the accuracy, precision, and recovery results from the SLV study, the method is suggested for a collaborative study on the determination of total and all-trans-β-carotene in dietary supplements.
Development and Validation of a Liquid Chromatographic Method for Fexofenadine Hydrochloride in Capsules
Authors: Breier Ana R , Paim Clésio S , Menegola Júulia , Steppe Martin , Schapoval Elfrides E S , Schapoval Elfrides E S 
Published: February 2020

Abstract
This paper describes the development and validation of a new, simple, fast, and sensitive liquid chromatographic method for the determination of the antihistamine fexofenadine. Although widely used in the treatment of allergic diseases, fexofenadine is not listed in any pharmacopeia, and there are few methods in the literature for its quantitation in pharmaceutical dosage forms. In this work, a LiChrospher® 100 RP-18 (250 × 4.0 mm, 5 μm) column was used as the stationary phase, and acetonitrile–5mM ammonium acetate buffer (50 + 50, v/v) at pH 3.2 was the mobile phase. Through the evaluation of the analytical parameters, it was shown that the method is linear (r = 0.9999) at concentrations ranging from 20.0 to 80.0 μg/mL, precise (intraday relative standard deviation [RSD] values = 0.85, 0.40, and 0.81%; interday RSD = 0.77%), accurate (mean recovery = 99.05%), specific, and robust. The detection and quantitation limits are 0.3409 and 1.033 μg/mL, respectively. These low values show the good sensitivity of the proposed method.
Enzymatic, Spectrophotometric Determination of Glucose, Fructose, Sucrose, and Inulin/Oligofructose in Foods
Authors: Steegmans Monique , Iliaens Saskia , Hoebregs Hubert 
Published: February 2020

Abstract
A fast, simple, and accurate method, using only standard laboratory equipment, was developed for the quantification of glucose, fructose, sucrose, and inulin/oligofructose in different food matrixes. Samples were extracted using boiling water and hydrolyzed with sucrase and fructanase. Sugars were determined in the initial extract and in both hydrolysates using an enzymatic, spectrophotometric kit for glucose and fructose determination with hexokinase, glucose-6-phosphate dehydrogenase, and phosphoglucose isomerase. Calculations of sucrose and inulin/oligofructose were based only on fructose measurement. Glucose results of the hydrolysates were not used for inulin/oligofructose calculations because of possible interference. Released glucose by the hydrolysis of maltose or by possible partial hydrolysis of other compounds like maltodextrines, starch, lactose, or maltitol could interfere in the measurement of the sucrase and the fructanase hydrolysates. To validate the method, a wide range of different food matrixes and different amounts of inulin/oligofructose (1–54%) were analyzed. Mean recovery ± relative standard deviation (RSD) for inulin or oligofructose was 96.0 ± 5.3%. The RSDr for inulin/oligofructose measured on 35 food samples, analyzed in duplicate, was 5.9%. Accuracy and precision of the method were less for samples with large concentrations of sucrose, maltose, maltodextrines, or s tarch (ratio to inulin/oligofructose &gt;4 to 1). Precision and accuracy were comparable with those of the ion exchange chromatographic method AOAC 997.08 and the enzymatic, spectrophotometric method AOAC 999.03. In contrast to 999.03, this method allows the accurate quantification of both GFn and Fn forms.