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Thousands of per- and polyfluoroalkyl substances (PFAS) exist in the environment and pose a potential health hazard. Suspect and nontarget screening with liquid chromatography (LC)–high-resolution tandem mass spectrometry (HRMS/MS) can be used for comprehensive characterization of PFAS. To date, no automated open source PFAS data analysis software exists to mine these extensive data sets. We introduce FluoroMatch, which automates file conversion, chromatographic peak picking, blank feature filtering, PFAS annotation based on precursor and fragment masses, and annotation ranking. The software library currently contains ∼7 000 PFAS fragmentation patterns based on rules derived from standards and literature, and the software automates a process for users to add additional compounds. The use of intelligent data-acquisition methods (iterative exclusion) nearly doubled the number of annotations. The software application is demonstrated by characterizing PFAS in landfill leachate as well as in leachate foam generated to concentrate the compounds for remediation purposes. FluoroMatch had wide coverage, returning 27 PFAS annotations for landfill leachate samples, explaining 71% of the all-ion fragmentation (CF2)n related fragments. By improving the throughput and coverage of PFAS annotation, FluoroMatch will accelerate the discovery of PFAS posing significant human risk.

The pigment lead white ((PbCO3)2·Pb(OH)2) was analyzed by LDI-MS/MS and LDI-Orbitrap-MS/MS for the first time. The elucidation of formulae from a suite of isotopically complex cluster ions was obtained from low- and high-resolution full- and tandem-mass spectra in concert with both deductive and inductive reasoning. The unique isotopic pattern of lead was used both to delineate the full-scan spectrum into superclusters and to identify the monoisotopic mass of each cluster, from which a lead-limited, accurate formula could be derived. Chemical formulae for the clusters of lead white followed the form PbxOyHz. Also, the in situ detection of lead white by LDI-MS was achieved for cross sections of painted works of art.

Cold stress syndrome (CSS) in the Florida manatee (Trichechus manatus latirostris) results in perturbations to many physiological pathways, often leading to further illness or death. In this study, we applied a non-targeted lipidomics approach with ultra-high performance liquid chromatography and high-resolution tandem mass spectrometry to characterize changes related to CSS in the lipidomic profiles of manatee plasma. Lipidomic analyses were conducted on healthy manatee (control) and cold-exposed manatee plasma samples with varying concentrations of Serum Amyloid A (SAA), an acute-phase protein that is associated with inflammatory disease. Control manatees (n = 10) were compared to all manatees exposed to cold temperatures (n = 17), and a subset of those manatees with SAA values > 120 μg/mL (n = 9). Increased SAA values were associated with higher levels of various acylcarnitine lipids, while several triacylglycerols and oxidized triacylglycerols were significantly lower in manatees with cold exposure. These identified lipids are critical molecules involved in the maintenance of energy homeostasis and could potentially be examined in conjunction with current physical parameters to characterize cold stress. The ability to detect such differences highlights the addition of lipidomics as a valuable tool in understanding cold stress and potentially other illnesses in manatees. Further investigation into the function of the altered lipids could greatly increase our understanding of lipid metabolism in physiologically stressed manatees as well as other marine mammals and inform future management recovery strategies.

A 9-week feeding trial was conducted with juvenile red drum, Sciaenops ocellatus, to evaluate the use of soy oil as a fish oil replacement. Three primary protein sources (fishmeal - FM, soybean meal - SBM, and soy protein concentrate - SPC) were utilized with 100% fish oil (FM, SBM, SPC), 75% fish oil (SBM, SPC), or 50% fish oil (FM, SBM, SPC) as the lipid source. Traditional growth and performance metrics (specific growth rate, feed consumption, feed conversion ratio) were tracked and tissue samples (liver, muscle, plasma, adipose, and brain) were collected for gas chromatography-based fatty acid profiling. Ten lipid metabolism related genes were analyzed for potential expression differences between dietary treatments in liver and muscle tissues and whole body and fillet tissues were sampled for proximate composition analyses. Forty- four fatty acids were measured by gas chromatography-flame ionization detector (GC-FID) and evaluated with principle component analysis and ANOVA to understand the dietary influence on lipid metabolism and health. Significant differences in growth rate were observed with the SBM 50% fish oil diet outperforming the FM 100% fish oil reference diet. All other soy protein-based diets performed statistically equivalent to both FM reference diets (100% and 50% fish oil) in regard to growth, however all soy protein-based formulations had significantly lower feed conversion ratios than the fishmeal-based references (p < .001). Gene expression differences were not significant in most cases, however often trended similarly as the observed performance. Fatty acid profiles differed as a function of oil source, with no apparent influence by protein source, with C18:2n-6 (linoleic acid) being-the primary differentiator. Overall, the six soy protein, fishmeal-free formulations performed equivalently or better than the fishmeal references with up to 50% of fish oil replaced by soybean oil.

Understanding the interaction between organisms and the environment is important for predicting and mitigating the effects of global phenomena such as climate change, and the fate, transport, and health effects of anthropogenic pollutants. By understanding organism and ecosystem responses to environmental stressors at the molecular level, mechanisms of toxicity and adaptation can be determined. This information has important implications in human and environmental health, engineering biotechnologies, and understanding the interaction between anthropogenic induced changes and the biosphere. One class of molecules with unique promise for environmental science are lipids; lipids are highly abundant and ubiquitous across nearly all organisms, and lipid profiles often change drastically in response to external stimuli. These changes allow organisms to maintain essential biological functions, for example, membrane fluidity, as they adapt to a changing climate and chemical environment. Lipidomics can help scientists understand the historical and present biofeedback processes in climate change and the biogeochemical processes affecting nutrient cycles. Lipids can also be used to understand how ecosystems respond to historical environmental changes with lipid signatures dating back to hundreds of millions of years, which can help predict similar changes in the future. In addition, lipids are direct targets of environmental stressors, for example, lipids are easily prone to oxidative damage, which occurs during exposure to most toxins. This is the first review to summarize the current efforts to comprehensively measure lipids to better understand the interaction between organisms and their environment. This review focuses on lipidomic applications in the arenas of environmental toxicology and exposure assessment, xenobiotic exposures and health (e.g., obesity), global climate change, and nutrient cycles. Moreover, this review summarizes the use of and the potential for lipidomics in engineering biotechnologies for the remediation of persistent compounds and biofuel production. With the preservation of certain lipids across millions of years and our ever-increasing understanding of their diverse biological roles, lipidomic-based approaches provide a unique utility to increase our understanding of the contemporary and historical interactions between organisms, ecosystems, and anthropogenically-induced environmental changes.

The peculiar ionization of anthraquinones, including the artistic dyes alizarin and purpurin, is examined. When alizarin (MW = 240) is ionized by either LDI or MALDI it exhibits a dominant ion of m / z 242 [M + 2H] + with a far greater abundance than expected from the 13 C isotopic contribution from the [M + H] + ion at m / z 241. For the first time, MS/MS analysis of these anomalous [M + 2H] + ions is presented, which indicates that they arise from a laser-induced photoreduction of one of the anthraquinone’s carbonyl groups. MS/MS daughter ions produced from neutral losses of either water or ammonia from the [M + 2H] + ions exhibit different relative abundances, depending upon their respective functional groups’ proximity to the reduced carbonyl. LDI-MS/MS was used for the in situ detection of alizarin in a painting cross section and a swatch of dyed silk.

A 9-week feeding trial was conducted with juvenile red drum, Sciaenops ocellatus, to evaluate the use of soy oil as a fish oil replacement. Three primary protein sources (fishmeal - FM, soybean meal - SBM, and soy protein concentrate - SPC) were utilized with 100% fish oil (FM, SBM, SPC), 75% fish oil (SBM, SPC), or 50% fish oil (FM, SBM, SPC) as the lipid source. Traditional growth and performance metrics (specific growth rate, feed consumption, feed conversion ratio) were tracked and tissue samples (liver, muscle, plasma, adipose, and brain) were collected for gas chromatography-based fatty acid profiling. Ten lipid metabolism related genes were analyzed for potential expression differences between dietary treatments in liver and muscle tissues and whole body and fillet tissues were sampled for proximate composition analyses. Forty- four fatty acids were measured by gas chromatography-flame ionization detector (GC-FID) and evaluated with principle component analysis and ANOVA to understand the dietary influence on lipid metabolism and health. Significant differences in growth rate were observed with the SBM 50% fish oil diet outperforming the FM 100% fish oil reference diet. All other soy protein-based diets performed statistically equivalent to both FM reference diets (100% and 50% fish oil) in regard to growth, however all soy protein-based formulations had significantly lower feed conversion ratios than the fishmeal-based references (p < .001). Gene expression differences were not significant in most cases, however often trended similarly as the observed performance. Fatty acid profiles differed as a function of oil source, with no apparent influence by protein source, with C18:2n-6 (linoleic acid) being-the primary differentiator. Overall, the six soy protein, fishmeal-free formulations performed equivalently or better than the fishmeal references with up to 50% of fish oil replaced by soybean oil.

Indiscriminate use of synthetic pesticides can be hazardous to both humans and the environment, but the use of natural products as a source of bio-based products, such as Melia azedarach extracts, is an interesting approach to overcome these hazards. Unfortunately, the limonoids found in M. azedarach with desired insecticidal properties (e.g. azadirachtin) may also be present with limonoids toxic to mammals. The goal of this report was to develop a fast and reliable MS-based experiment to characterize meliatoxins in crude extracts of M. azedarach, in order to provide unequivocal assessment of the safety for extracts for application in the field. MS and MS/MS experiments using MALDI ionization were evaluated as tools for the assignment of characteristic ions produced by each meliatoxin in crude extracts. The use of different experiments in combination, such as the analysis of fragment m/z 557 and [M + Na]+ (adducts ions m/z 681 and m/z 667), MALDI-MS can be used for detection of meliatoxins A1/B1 or A2/B2 in a crude extract and may be used to discriminate meliatoxins A from B, respectively. Subsequent MS/MS experiments can distinguish between the presence of group 1 and/or 2 in each class of meliatoxins classifying the proposed approach as a quick and efficient quality control method of meliatoxins in real M. azedarach samples.

Introduction – Melia azedarach adapted to cool climates was selected as rootstocks for vegetative propagation of Azadirachta indica. Cleft grafting of A. indica on M. azedarach rootstock showed excellent survival. Little is known about the chemistry of grafting. Objective – The roots, stems, leaves and seeds of this graft were examined in order to verify if grafted A. indica would produce limonoids different from those found in non-grafted plants. Intact matured fruits were also studied to verify if they were free of meliatoxins. Methodology – After successive chromatographic separations the extracts afforded several limonoids. HPLC-MS/MS and MALDI-MS were used to develop sensitive methods for detecting azadirachtin on all aerial parts of this graft and meliatoxins in fruits, respectively. Results – The stem afforded the limonoid salannin, which was previously found in the oil seeds of A. indica. Salannin is also found in the root bark of M. azedarach. Thus, the finding of salannin in this study suggests that it could have been translocated from the M. azedarach rootstock to the A. indica graft. HPLC-MS/MS analyses showed that azadirachtin was present in all parts of the fruits, stem, flowers and root, but absent in the leaves. The results of MALDI-MS analyses confirmed the absence of meliatoxins in graft fruits. Conclusion – This study showed that A. indica grafted onto M. azedarach rootstock produces azadirachtin, and also that its fruits are free of meliatoxins from rootstocks, confirming that this graft forms an excellent basis for breeding vigorous Neem trees in cooler regions. Copyright © 2010 John Wiley & Sons, Ltd.

Chemically functional magnetic nanoparticles, comprised of an Fe core encased in a thin Au shell, have been prepared by sequential high temperature decomposition of organometallic compounds in a coordinating solvent. A novel approach to encapsulate the Fe core in Au has been developed. TEM analysis confirms that the nanoparticles are monodisperse (∼20%) with average diameters of 8nm. The nanoparticles were subsequently functionalized with alkanethiolate ligands, which prevent aggregation, enable solubility in a range of solvents (both hydrophobic and hydrophilic), and permit subsequent derivatization (e.g., via ligand exchange reactions). The functionalized particles are characterized using high-resolution transmission electron microscopy (HRTEM), X-ray powder diffraction (XRD) and ultraviolet-visible (UV-Vis) absorption spectroscopy.We have utilized place-exchange to impart chemical functionality to the nanoparticles by attaching either (1) thiol-derivatized redox moieties (e.g., ferrocene) or (2) alkanethiols with terminal reactive groups such as alcohols, amines and carboxylic acids. This paper presents our preliminary investigations of the voltammetry of the former class of these magnetic core/shell nanoparticles.