William Craig Byrdwell

Vitamin D and Sterol Composition of 10 Types of Mushrooms from Retail Suppliers in the United States

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) in Agaricus bisporus (white button, crimini, portabella) and enoki, moderate in shiitake and oyster (0.4-0.7 μg/100 g), and high in morel, chanterelle, maitake (5.2-28.1 μg/100 g) and UV-treated portabella (3.4-20.9 μg/100 g), with significant variability among composites for some types. Ergosterol (mg/100 g) was highest in maitake and shiitake (79.2, 84.9) and lowest in morel and enoki (26.3, 35.5); the range was <10 mg/100 g among white button composites but 12-50 mg/100 g among samples of other types. All mushrooms contained ergosta-5,7-dienol (22,23-dihydroergosterol) (3.53-18.0 mg/100 g) and (except morel) ergosta-7-enol. Only morel contained brassicasterol (28.6 mg/100 g) and campesterol (1.23-4.54 mg/100 g) and no ergosta-7,22-dienol. MS was critical in distinguishing campesterol from ergosta-7,22-dienol.

Analysis of Genetically Modified Canola Varieties by Atmospheric Pressure Chemical Ionization Mass Spectrometric and Flame Ionization Detection

Abstract 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 was based on the diacylglycerol fragments and on the protonated molecular ion [M+H]+, except trisaturates which gave no [M+H]+. Triacylglycerols were identified and quantitated in normal, high stearic acid and high lauric acid canola varieties by the RP-HPLC/APCI-MS technique. The LC/APCI-MS identification of canola oil triacylglycerols allowed their quantitation by reverse phase HPLC coupled with a commercial flame ionization detector (FID). There was agreement between fatty acid composition obtained by LC/APCI-MS and LC-FID. However, the triacylglycerol resolution obtained by LC/APCI-MS, was superior to LC-FID in the qualitative identification of triacy...

Comparison of Analysis of Vitamin D3 in Foods Using Ultraviolet and Mass Spectrometric Detection

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(2)) from AOAC 2002.05 to produce a method that was applicable to a variety of food samples. Results for skim milk, orange juice, breakfast cereal, salmon, a diluted USP reference standard (vitamin D(3) in peanut oil), and processed cheese are presented. Results indicated that UV detection was adequate in most cases, but the absence of interfering species must be determined in each food by mass spectrometry. Selected ion monitoring (SIM) atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) was shown to produce statistically indistinguishable results compared to UV detection for the skim milk, orange juice, multigrain cereal, and salmon samples. The processed cheese exhibited interferences that precluded quantification of vitamin D(3) by UV detection, and therefore, only SIM APCI-MS data for that sample were valid.

Vitamin D content and variability in fluid milks from a US Department of Agriculture nationwide sampling to update values in the National Nutrient Database for Standard Reference

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 from 24 statistically selected supermarkets in the United States. Additionally, 2% milk samples from an earlier 2001 USDA nationwide collection were reanalyzed. Vitamin D(3) was determined using a specifically validated method involving HPLC with UV spectroscopic detection and vitamin D(2) as an internal standard. Quality control materials were analyzed with the samples. Of the 120 milk samples procured in 2007, 49% had vitamin D(3) within 100 to 125% of 400 IU (10 μg)/qt (label value), 28% had 501 to 600 IU (12.5-15 μg)/qt, 16% had a level below the label amount, and 7% had greater than 600 IU (15 μg)/qt (>150% of label). Even though the mean vitamin D(3) content did not differ statistically between milk types, a wide range in values was found among individual samples, from nondetectable [<20 IU (0.5 μg)/qt] for one sample to almost 800 IU (20 μg)/qt, with a trend toward more samples of whole milk having greater than 150% of the labeled content. On average, vitamin D(3) in 2% milk was higher in 2007 compared with in 2001 [473 vs. 426 IU (11.8 vs. 10.6 μg)/qt].

Effects of UV-B Radiation Levels on Concentrations of Phytosterols, Ergothioneine, and Polyphenolic Compounds in Mushroom Powders Used As Dietary Supplements

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 antioxidant, ergothioneine; other natural polyphenolic compounds, e.g., flavonoids, lignans, etc.; and selected phytosterols. Four types of mushroom powder consisting of white, brown (Agaricus bisporus), oyster (Pleurotus ostreatus), and shiitake (Lentinula edodes) mushrooms from three different treatment groups (control, low and high UV-B exposures) were evaluated. Ergothioneine concentrations found in mushroom powders were 0.4-10.4 mg/g dry weight (dw) and were not appreciably affected by UV-B radiation. No individual polyphenols were detected above 0.1 μg/g. Phytosterols ergosterol (2.4-6.2 mg/g dw) and campesterol (14-43 μg/g dw) were measured in mushroom powder samples. Ergosterol concentrations decreased significantly with the increased level of UV-B treatment for all mushroom powder types, except for white. These results provide some new information on effects of UV-B radiation on these important natural bioactive compounds in mushrooms.

Dual parallel mass spectrometry for lipid and vitamin D analysis.

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. However, the duty cycle of the mass spectrometer places limits on the number of experiments that can be performed, and instruments usually employ only one type of ionization at a time. This work describes the approaches we have used that employ two mass spectrometers in parallel or in a column-switching configuration that allows multiple ionization modes and types of experiments to be conducted simultaneously during a single chromatographic run. These data demonstrate how use of two systems can reduce or eliminate the need for repeat injections and repetitive experiments. Approaches are described that employ two mass spectrometers connected in parallel as detectors for a single chromatographic system (LC1/MS2) or that employ two liquid chromatographs and two mass spectrometers in a column-switching arrangement (LC2/MS2). Examples of LC1/MS2 analyses of triacylglycerols (TAGs), sphingolipids, and vitamin D are given, as well as an example of an LC2/MS2 experiment that is used to perform analysis of both polar and non-polar lipids in a total lipid extract.

The Updated Bottom Up Solution applied to mass spectrometry of soybean oil in a dietary supplement gelcap

AbstractAmong 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 the desired information. Critical Ratio 1, [MH]+/Σ[DAG]+, is correlated to the degree of unsaturation ([MH]+ is the protonated molecule and Σ[DAG]+ is the sum of diacylglycerol-like ions, [DAG]+); Critical Ratio 2, [AA]+/[AB]+ for Type II TAGs (“ABA/AAB/BAA”) and [AC]+/([AB]++[BC]+) for Type III TAGs (“ABC/CBA/BAC/CAB/ACB/BCA”), is correlated to identification of regioisomers; and Critical Ratio 3, [BC]+/[AB]+, provides information about those [DAG]+ from Type III TAGs. Furthermore, Critical Ratios are used in the Updated Bottom Up Solution (UBUS) to reproduce the mass spectra of TAGs by atmospheric pressure chemical ionization mass spectrometry applied to analysis of soybean oil in a dietary supplement gelcap. We present a new model for the [MH]+/Σ[DAG]+ ratio, quantify regioisomers using the [AA]+/[AB]+ ratio, and describe trends for [BC]+/[AB]+ that have never been reported before. The UBUS is also applied to other classes of molecules, i.e., vitamin D and DAGs. The amount of vitamin D3 in the gelcap fell from 2011 ± 22 when received to 1689 ± 33 just prior to expiration. The Critical Ratios constitute a compact data set that can provide structural information and also act as a library of mass spectra. Graphical AbstractThe shape of the Updated Bottom Up Solution for Type II triacylglycerols

Construction of a Wireless Communication Contact Closure System for Liquid Chromatography with Multiple Parallel Mass Spectrometers and Other Detectors

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 autosamplers are converted to simple contacts by powered relay boards that are then connected to two 16-channel wireless contact closure sender boards. The contact closure signals from the two sender boards are transmitted wirelessly to two pairs of eight-channel receiver boards (total of 32 contact signals) that distribute the start signal to 14 switches that allow selection of which start signal is sent to which instrument, pump, or detector. The contact closure system is used for quadruple parallel mass spectrometry experiments in which four mass spectrometers, using three different atmospheric pressure ionization modes, plus a UV detector, an evaporative light-scattering detector, a corona charged aerosol detector, and two syringe pumps supplying electrolyte, are all synchronized to start simultaneously. A wide variety of liquid chromatography–mass spectrometry experiments using multiple liquid chromatographs and mass spectrometers simultaneously, LCx/MSy, including column-switching experiments, can be reconfigured simply by toggling switches.

The Simulacrum System as a Construct for Mass Spectrometry of Triacylglycerols and Others

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, specifically a simulacrum sum, four Possibilities to Observe, two Cases, and eight solutions. A simulacrum with no restrictions is the First General Form of a Simulacrum. When one value is specified to be 1 (as in MS), the construct is called a Unit Simulacrum, also called the First Specified Form of a Simulacrum. When one value is 1 and no value can be greater than 1 (the two specifications dictated by mass spectrometry), the construct is called the Second Specified Form of a Simulacrum, or the Mass Spectrometry Simulacrum. Simulacra are used with three Critical Ratios calculated from raw abundances in mass spectra of TAG to provide structural information about the degree of unsaturation in TAG, the identity and quantity of regioisomers, and other structural characteristics. Three-level-deep nested simulacrum solutions yield the recently reported Updated Bottom Up Solution, from which the protonated molecule, [MH]+, and all diacylglycerol-like fragments, [DAG]+, of TAG can be reproduced from the Critical Ratios. Thus, the simulacrum solutions constitute a reduced data set in which more information is provided in fewer values than raw abundances, such that the Critical Ratios constitute a compact library of mass spectra.