William Craig Byrdwell

United States Department of Agriculture | USDA · Methods and Application of Food Composition Lab

A new series of equations for space, mass and the Periodic Table based on a common pattern is presented. Three equations for circular space represent the circumference (C), area (A), and volume (V) of a circle or sphere, which are mathematically equivalent to the conventional equations, specifically, C=2(pi)r, A=(pi)r^2, and V=4/3(pi)r^3. The new e...

Two-dimensional liquid chromatography (2D-LC) is now commercially available and is being implemented in an increasing number of laboratories around the world. Normally, 2D-LC is done using one or more detectors at the end of the second dimension, ^2D, and the first dimension, ^1D, is reconstructed from numerous slices across the ^1D peaks. As a res...

Three dimensions of chromatographic separation, using split-flow two-dimensional liquid chromatography (SF-2D-LC) with two parallel second dimensions, LC × 2LC, combined with quadruple parallel mass spectrometry (LC3MS4) is demonstrated for analysis of NIST SRM 1849a adult/infant formula. The first dimension, 1D, was a conventional non-aqueous reve...

The Simplified Case for Whole PI and Alternative Equations for Space, Mass, and the Periodic Table is simplified by the fact that it does not contain the accurate-mass approximations for monoisotopic atomic masses. This manuscript describes the Pi Paradox, the need for Whole PI, the construction of Whole PI, and how understanding Whole PI leads t...

Acylglycerols (AGs), or glycerides (GLs), are active biomolecules in their own right but also act as the foundational building blocks for multiple classes of the most common lipids. Because of this, most of the fragments observed from mass spectrometry (MS) of monoglycerides (MGs), diglycerides (DGs), and triglycerides (TGs) are common to multiple...

A short 10‐min ultra high performance liquid chromatography (UHPLC) method was used for separation and lipidomic analysis of triacylglycerols (TAGs) in 10 pulses: baby lima beans, black beans, black‐eyed peas, butter beans, cranberry beans, garbanzo beans, green split peas, lentils, navy beans, and pinto beans. The lipids extracted using chloroform...

Gas chromatography (GC) with flame ionization detection (FID) and mass spectrometry (MS) detection were used to characterize the fatty acid (FA) compositions of ten commonly consumed (i.e., market class) pulses. Lipids from ground pulses were extracted using a classical chloroform/methanol extraction and quantified by GC-FID with structural confirm...

Pulses are seeds produced from legumes. More specifically, the United Nations Food and Agricultural Organization (FAO) defines pulses as “Leguminosae crops harvested exclusively for their grain, including dry beans, peas and lentils”. This excludes oilseeds, such as soybeans and peanuts. Pulses are well known for their high content of protein a...

Two-dimensional liquid chromatography (2D-LC) is commercially available and has become increasingly common in laboratories across the world. Most 2D-LC systems that are coupled to mass spectrometry use one mass spectrometer attached to the outlet of the second dimension, and the first dimension is reconstructed by “stitching together” the signal fr...

In this study, we have developed and validated a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method using a tandem sector quadrupole mass spectrometer to simultaneously detect and quantify three curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) and three of the most common food adulterants, particularly in turmeric,...

The fatty acid compositions, including isomer compositions, of seven seed oils containing conjugated fatty acids (CFA) were determined. Seed oils were extracted using a modified Folch extraction, converted to fatty acid methyl esters, and analyzed by gas chromatography (GC) with mass spectrometry and flame ionization detection. The MS detector was...

The compositions of molecular species of structural lipids and storage lipids of two types of lettuce leaves, romaine (green leaf) and Lolla Rossa (red leaf), are reported. Lettuce was harvested at two ages, three weeks (microgreens) and eight weeks (mature), and analyzed by liquid chromatography-mass spectrometry. Samples grown under natural light...

Lipids comprise large and disparate classes of molecules having very different overall polarities, but the one characteristic they typically have in common is a nonpolar hydrocarbon chain that is hydrophobic in nature. The characteristics of each class of lipid dictate the most appropriate tool and approach for analysis. Since many PLs are inherent...

Objective: Short-chain triacylglycerols (TAGs) in lipid extracts of biological samples are not sufficiently resolved using conventional reversed-phase separation on two C18 columns in series, or using a two-dimensional chromatographic separation with a silver ion column as the second dimension (2D). An additional dimension of separation was requir...

Most chromatographic and mass spectrometric instruments include workstations that allow data processing and target compound quantification. However, the software used for quantification does not all use common approaches for statistical treatment of data. Presented here is a brief description of three commonly used workstation software packages (WS...

This report demonstrates comprehensive 2D-LC in which two mass spectrometers in parallel plus four other detectors (UV, FLD, CAD, and ELSD) are used to monitor the first dimension (1D), while two more mass spectrometers in parallel plus a UV detector are used to monitor the second dimension (2D). LC1MS2 x LC1MS2 = LC2MS4 was employed to identify an...

Atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), and electrospray ionization (ESI) have gained widespread popularity to couple liquid chromatography to mass spectrometry. APCI-MS and APPI-MS produce similar mass spectra, while ESI-MS produces mostly adduct ions useful for further MS/MS, unless some energ...

Montmorency sour cherry (Prunus cerasus L.) pit oil (CPO) was extracted and characterized by various methods including: GC, LC–MS, NMR, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD). The oil gave an acid value of 1.45 mg KOH/g, saponification value of 193 mg KOH/g and unsaponifiable mat...

Article at The Lipid Library: http://lipidlibrary.aocs.org/lipid-analysis/lipidomics/parallel-mass-spectrometry-(apci-ms-and-esi-ms)-for-lipid-analysis. Different atmospheric pressure ionization sources produce different balances between intact molecule ions and fragments. That balance between intact ions and fragments obtained by APCI-MS is grea...

A construct called a simulacrum is defined that provides all possible solutions to a sum of two mass spectral abundances, based on values (abundances) or ratios of those values. The defined construct is applied to atmospheric pressure chemical ionization mass spectrometry (MS) of triacylglycerols (TAG). A simulacrum has precisely defined components...

Recent developments have finally allowed fragment behaviors using APCI-MS to be elucidated after twenty years of literature reports. Critical Ratios have been defined that correspond to various aspects of triacylglycerol (TAG) analysis, from overall degree of unsaturation to localization of fatty acids on the glycerol backbone (regioisomers), to gr...

The Updated Bottom Up Solution (UBUS) was recently applied to atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) of triacylglycerols (TAG). This report demonstrates that the UBUS applies equally well to atmospheric pressure photoionization (APPI) MS and to electrospray ionization (ESI) MS. Critical Ratio 1 (CR1), the [MH]+/∑[DAG...

New, faster methods have been developed for analysis of vitamin D and triacylglycerols that eliminate hours of wet chemistry and preparative chromatography, while providing more information than classical methods for analysis. Unprecedented detail is provided by combining liquid chromatography with the power of three or four mass spectrometers used...

Among the goals of lipidomics applied to triacylglycerols (TAGs) is identification of molecular species, degree and location of unsaturation, and positions of fatty acyl chains (i.e., identification of regioisomers). Toward those ends, we define one, two, and three “Critical Ratios” for Types I, II, and III TAGs that provided different aspects of t...

An 'extract-filter-shoot' method for the analysis of vitamin D2 , ergocalciferol, in a dry powdered dietary supplement capsule containing rice flour excipient and in a National Institute of Standards and Technology standard reference material 3280 is reported. Quantification of vitamin D2 was done by atmospheric pressure chemical ionization mass sp...

A contact closure system was constructed that uses two contact closure sender boards that communicate wirelessly to four contact closure receiver boards to distribute start signals from two or three liquid chromatographs to 14 instruments, pumps, detectors, or other components. Default high, closed low, TTL logic (5-volt) start signals from two aut...

Compositional changes of powder dietary supplements made from mushrooms exposed to different levels of UV-B irradiation were evaluated for the bioactive naturally occurring mushroom anti-oxidant, ergothioneine, other natural polyphenolic compounds: e.g. flavonoids, lignans, etc., and selected phytosterols. Four types of mushroom powder consisting o...

A method is demonstrated for analysis of vitamin D fortified dietary supplements that eliminates virtually all chemical pretreatment prior to analysis, which is referred to as a "dilute-and-shoot" method. Three mass spectrometers, in parallel, plus a UV detector, an evaporative light-scattering detector (ELSD), and a corona charged aerosol detector...

Vitamin D(2) (ergocalciferol) and sterols were analyzed in mushrooms sampled nationwide in the United States to update the USDA Nutrient Database for Standard Reference. Vitamin D(2) was assayed using HPLC with [(3)H]-vitamin D(3) internal standard and sterols by GC-FID mass spectrometric (MS) confirmation. Vitamin D(2) was low (0.1-0.3 μg/100 g) i...

Samples of vitamin D fortified orange juice obtained from retail food stores were analyzed for vitamin D3 content using a method developed by combining the best features of two AOAC methods. Detection by ultraviolet absorption at 265 nm was compared to detection by selected ion monitoring (SIM) using atmospheric pressure chemical ionization (APCI)...

Abstract # 2009 A method is demonstrated for analysis of vitamin D fortified dietary supplements that eliminates virtually all chemical pretreatment prior to analysis, referred to as a ‘dilute and shoot’ method. Three mass spectrometers, in parallel, plus a UV detector, an evaporative light scattering detector (ELSD), and a corona charged aerosol d...

This study determined the vitamin D(3) content and variability of retail milk in the United States having a declared fortification level of 400 IU (10 μg) per quart (qt; 1 qt=946.4 mL), which is 25% daily value per 8 fluid ounce (236.6 mL) serving. In 2007, vitamin D(3) fortified milk (skim, 1%, 2%, whole, and 1% fat chocolate milk) was collected f...

There are numerous options for mass spectrometric analysis of lipids, including different types of ionization, and a wide variety of experiments using different scan modes that can be conducted. Atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) provide complementary types of information that are both desirable. Howev...

A method for analysis of vitamin D(3) in commonly fortified foods and in fish, which contains endogenous vitamin D(3), was developed by combining the best aspects of two official methods. The ethyl ether/petroleum ether extraction procedure from AOAC 992.26 was combined with the chromatographic separation and use of an internal standard (vitamin D(...

As part of the United States Department of Agriculture's (USDA) National Food and Nutrient Analysis Program (NFNAP), food composition data for vitamin D in the USDA National Nutrient Database for Standard Reference are being updated and expanded, focusing on high priority foods and validated analytical methodology. A lack of certified reference mat...

This report briefly reviews existing methods for analyzing the vitamin D content of fortified and unfortified foods. The existing chemical methods are similar; all are time consuming, require experienced technicians, and have only been validated for a few materials (eg, dairy products or animal feed materials). This report also describes the lack o...

This report briefly reviews existing methods for analyzing the vita- min D content of fortified and unfortified foods. The existing chem- icalmethodsaresimilar;allaretimeconsuming,requireexperienced technicians, and have only been validated for a few materials (eg, dairy products or animal feed materials). This report also describes the lack of sta...

Total lipid extracts containing both polar and non-polar lipids were separated using two liquid chromatographic systems joined together using a column-switching valve. Detection was accomplished using mass spectrometers attached to each of the two liquid chromatographic systems, for a dual liquid chromatography/dual mass spectrometry (LC2/MS2) arra...

Liquid chromatography coupled to atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) mass spectrometry (MS), in parallel, was used for simultaneous detection of bovine milk sphingolipids (BMS). APCI-MS mass spectra exhibited mostly ceramide-like fragment ions, [Cer-H(2)O+H](+) and [Cer-2H(2)O+H](+), which were used to...

Triacylglycerol species (TAG) of oils from five genetically modified soybean varieties were resolved by gradient reversed phase high performance liquid chromatography. The eluting TAG were detected and quantitated without the requirement for TAG response factors or calibration curves for the detector response by an improved evaporative light scatte...

Liquid chromatography coupled to atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) mass spectrometry (MS), in parallel, was used for detection of bovine brain and chicken egg sphingolipids (SLs). APCI-MS mass spectra exhibited mostly ceramide-like fragment ions, [Cer-H(2)O+H](+) and [Cer-2H(2)O+H](+), whereas ESI-MS...

Canola oil triacylglycerols from genetically modified canola lines were conclusively identified by reverse phase HPLC coupled with atmospheric pressure chemical ionization mass spectrometric (APCI-MS) detection. APCI-MS is a soft ionization technique, which gave simple spectra for triacylglycerols. Spectral identification of the triacylglycerols wa...

The composition and structures of triacylglycerols (TAG) in a commercially prepared hydrogenated soybean oil margarine basestock [iodine value (IV) 65, 39.7% trans fatty acids] were determined by high-performance liquid chromatography (HPLC) in tandem with atmospheric pressure chemical ionization (APCI) mass spectrometry (MS). The basestock was sep...

Presented here is an approach to representing the data from atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) of triacylglycerols (TAG) using a set of one, two, or three Critical Ratios. These Critical Ratios may be used directly to provide structural information concerning the regioisomeric composition of the triacylglycerols...

Reported are the on-line LC/electrospray ionization MS of large, high M.W. oligomers formed from heated triolein, a TAG used as a model for dietary oils. Triolein, the major component of olive oil, canola oil, and other dietary oils, was heated at frying temperature, and the TAG oxidation products were separated using RP-HPLC coupled to an ion trap...

A commercially available bovine brain total lipid extract containing polar and non-polar lipid fractions has been separated in one analytical run using two high performance liquid chromatography (HPLC) systems in parallel, coupled to dual mass spectrometers, in parallel. The whole extract of bovine brain was separated on normal phase (NP, LC1) and...

Most lipid extraction procedures [Folch, J., Lees, M., and Sloane-Stanley, G.H. (1957) A Simple Method for the Isolation and Purification of Total Lipids from Animal Tissues, J. Biol. Chem. 226, 497-509; Bligh, E.G., and Dyer, W.J. (1959) A Rapid Method of Total Lipid Extraction and Purification, Can. J. Biochem. Physiol. 37, 911-917] employ biphas...

Triacylglycerol (TAG) compositions, as mole percent, were obtained by reverse phase high performance liquid chromatography (RP-HPLC), coupled with atmospheric pressure chemical ionization mass spectrometry (APCI-MS) of lard and mutton tallow fractions under consideration for food formulation products. Accurate identification and quantitation of the...

Two mass spectrometers, in parallel, were employed simultaneously for analysis of triacylglycerols in canola oil, for analysis of triolein oxidation products, and for analysis of triacylglycerol positional isomers separated using reversed-phase high-performance liquid chromatography. A triple quadrupole mass spectrometer was interfaced via an atmos...

Two mass spectrometers, in parallel, were employed simultaneously for analysis of triacylglycerols in canola oil, for analysis of triolein oxidation products, and for analysis of triacylglycerol positional isomers separated using reversed-phase high-performance liquid chromatography. A triple quadrupole mass spectrometer was interfaced via an atm...

Atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) has proven to be a very valuable technique for analysis of lipids from a variety of classes. This instrumental method readily produces useful ions with gentle fragmentation from large neutral molecules such as triacylglycerols and carotenoids, which are often difficult to analyz...

Reversed-phase HPLC resolution and HPLC-flame ionization detection quantitation of model triacylglycerol positional isomer pairs (important in the study of food formulation lipids) after facile conversion to brominated derivatives is reported. The positional isomers in the triacylglycerol pairs were at least 98% resolved from each other during reve...

Triacylglycerol (TAG) compositions by area percent were obtained by reverse-phase high-performance liquid chromatography (RP-HPLC) coupled with atmospheric pressure chemical ionization mass spectrometry (APCI-MS) of highly saturated fatty acid fats, such as coconut, cocoa butter, palm, randomized palm, palm olein, and randomized palm olein oils. Ac...

To determine sources of desirable deep-fried flavor in frying oils, degradation products from heated triolein and trilinolein with 5-31% polar compounds representing low to high deterioration were evaluated by purge-trap gas chromatography-mass spectrometry-olfactometry. (E,E)-2,4-Decadienal, 2-heptenal, 2-octenal, 2,4-nonadienal, and 2,4-octadiena...

Normal, high stearic acid and high lauric acid canola oil varieties were heated in the presence of air to allow autoxidation to occur. After the reaction, the oils were analyzed using a non-aqueous reversed-phase high-performance liquid chromatographic separation followed by detection using atmospheric pressure chemical ionization mass spectrometry...

Several margarine base stock candidates have previously been prepared for the purpose of finding better, more oxidatively stable food components: high-saturate vegetable oils, randomized vegetable oils, vegetable oil-hard stock blends, and interesterified vegetable oil-hard stock blends. Here are reported the triacylglycerol compositions of these p...

To better understand production of undesirable or negative odors such as fruity, plastic, and waxy that are characteristic of higher oleic acid-containing oils, model heated oil systems of triolein and trilinolein were studied. Identification of the odor significance of volatile compounds produced by fractionated and nonfractionated triolein and tr...

The triacylglycerol compositions of several margarine basestocks, including blends and interesterified blends of corn and soybean oils with cottonseed oil stearine, randomized corn oil and randomized soybean oil, were determined. Quantitative results obtained by reversed-phase high performance liquid chromatography for samples of known composition...

Oxidation products from triolein under model heated frying conditions have been analyzed using liquid chromatography with an evaporative light scattering detector and atmospheric pressure chemical ionization (APCI) mass spectrometric detection. Triolein was heated at 190 degrees C with 2% water added each hour, to simulate the moisture of a frozen...

Oxidation products from the autoxidation of three triacylglycerol standards have been analyzed using reversed-phase high-performance liquid chromatography (RP-HPLC) coupled to mass spectrometry via an atmospheric pressure chemical ionization (APCI) source. Triolein, trilinolein and trilinolenin were autoxidized in the dark at 50–60°C until the oxid...

Atmospheric pressure chemical ionization mass spectrometry (APCI-MS) coupled to reversed-phase high performance liquid chromatography (RP-HPLC) was used for direct analysis of intact triacylglycerols (TAGs) from hydroxy-containing plant oils. Castor bean oil, Lesquerella fendleri and Lesquerella gordonii oils were separated into tri-hydroxy, di-hyd...

Analysis of phospholipids was performed using a liquid chromatographic separation with two mass spectrometers in parallel providing electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) data simultaneously from a triple quadrupole instrument and a single quadrupole instrument, respectively. The output from UV-Vis and eva...

Allylic amination of methyl oleate with bis(N-p-toluenesulfonyl) sulfodiimide results in a mixture of methyl 11-amino-(N-p-toluenesulfonyl)-9-E-octadecenoate and methyl 8-amino-(N-p-toluenesulfonyl)-9-E-octadecenoate in 58% yield. These novel products were isolated and characterized by nuclear magnetic resonance, infrared spectroscopy, mass spectr...

The identity of the major phospholipid component of human lens membrane extracts, previously referred to as the 'unknown phospholipid', was recently proposed to be 4,5-dihydrosphingomyelin (DHS). Using high-performance liquid-chromatographic separation with atmospheric pressure chemical ionization and electrospray ionization mass-spectrometric dete...

Atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) was used for quantitative analysis of triglycerides (TG) separated by reverse-phase high-performance liquid chromatography. APCI-MS was used for analysis of mono-acid TG standards containing deuterated internal standard, of a synthetic mixture of heterogeneous TG, of randomized an...

Dihydrosphingomyelin (DHS) is the major phospholipid in the human lens. The influence of this phospholipid on membrane structure and function is not known. In this study we used infrared spectroscopy to determine the thermodynamic and molecular structural properties of the hydrocarbon chains of DHS membranes isolated from human lenses. The phase tr...

In other systems, proteins have been shown to alter the molecular structures of lipids in the cell membrane bilayer. We wished to determine if proteins altered the structure of lens lipids. The structure of lipid hydrocarbon chains in urea purified human lens membrane vesicles containing intrinsic, hydrophobically bound proteins was compared to the...

Age related changes in the lipid composition of human lens membranes have been documented and could be responsible for alterations in the function of lens membranes. To establish age related lipid composition-membrane structure relationships, we have examined spectroscopically the hydrocarbon chain structure of lipid membranes from human lens corte...

Soybean oil triacylglycerols from genetically modified soybean lines were conclusively identified by reversed-phase high-performance liquid chromatography coupled with mass spectrometry with atmospheric pressure chemical ionization. Atmospheric pressure chemical ionization is a soft ionization technique which gives simple spectra for triacylglycero...

Unusual seed oils having significance for chemical synthesis, Crepis alpina, or with fatty acids which contain functional groups important in the preparation of plastics, Vernonia galamensis, were analyzed by a new reversed-phase high performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry technique. Using this...

Regional differences in human lens membrane lipid composition have been documented and could be responsible for alterations in the function of lens membranes. The phospholipid composition of epithelial membranes of human lenses has been shown to be different from that of fiber membranes. To establish lipid composition-membrane structure relationshi...

Atmospheric pressure chemical ionization (APCI) mass spectrometry was investigated as a new method for analysis of a mixture of triglycerides separated by reverse-phase high-performance liquid chromatography. A mixture of homogeneous (monoacid) triglyceride standards containing fatty acids with zero to three double bonds was analyzed to demonstrate...

The major component of human lens membranes was thought to be sphingomyelin until 1991, when a study by phosphorus-31 (31P) nuclear magnetic resonance (NMR) spectroscopy revealed the presence of an unknown phospholipid that constituted approximately half the human lens phospholipids. The objective of this work was to isolate this phospholipid and t...

The long-term purpose of this research was to establish the relationships between composition, structure, and function that affect human lens membranes. The authors hypothesized that the functional differences of epithelial, cortical, and nuclear lens membranes are related to compositional differences. Furthermore, age-dependent alterations in memb...

The authors compared the specific green and blue fluorescence levels in soluble and insoluble fractions (cortical and nuclear) extracted from cataractous lenses with those corresponding to clear lenses and tried to establish the nature of the role of extrinsic fluorophores in cataractogenesis. Laser-induced fluorescence was measured with an optical...