The measurement of intestinal permeability is important for diagnoses of diseases of the gastrointestinal tract, such as Crohn’s disease. The gold standard for measurement of intestinal permeability is the dual sugar absorption test, which measures the urinary or blood concentrations of two orally administered sugars, a monosaccharide and a disaccharide, over a period of time. The lining of the small intestine allows monosaccharides to cross into the bloodstream, but the larger disaccharide is not permitted to cross the intestine unless the barrier is compromised. The permeability of the lining is measured by a ratio between select monosaccharides and disaccharides, and this indicates the overall status of the small intestine. In order to study the effects of resistance exercise on intestinal permeability in human subjects, we developed a liquid chromatography tandem mass spectrometry (LC–MS/MS) method for the analysis of saccharides in blood plasma. The analytes included rhamnose, a monosaccharide not commonly found in food, and lactulose, a disaccharide. A trisaccharide, raffinose, was used as an internal standard. The method was robust, and had consistent reliability.

Algal lipids are important molecules to store energy in algae and transfer energy in the marine food chain, and are potential materials for high value nutraceuticals (e.g., omega‐3 fatty acids) or biofuel production. However, how lipid biosynthesis is regulated is not well understood in many species including Eutreptiella from the phylum of Euglenozoa. Here, we characterized the fatty acid (FA) profile of an Eutreptiella species isolated from Long Island Sound, USA, using gas chromatography–tandem mass spectrometry (GC/MS/MS) and investigated their biosynthesis pathways by transcriptome sequencing. We discovered 24 types of FAs including a relatively high proportion of long‐chain unsaturated FAs. The abundances of C16, C18, and saturated FAs decreased when phosphate in the culture medium was depleted. Among the 24 FAs, docosahexaenoic acid (C22:6 ∆4,7,10,13,16,19 ) was most abundant, suggesting that Eutreptiella sp. preferentially invests in the synthesis of long‐chain polyunsaturated fatty acids (LC‐PFAs). Further transcriptomic analysis revealed that Eutreptiella sp. likely synthesizes LC‐PFAs via ∆8 pathway and uses type I and II fatty acid synthases. Using RT–qPCR, we found that some of the lipid synthesis genes, such as β‐ketoacyl‐ACP reductase, fatty acid desaturase, acetyl‐CoA carboxylase, acyl carrier protein, ∆8 desaturase, and Acyl‐ACP thioesterase, were more actively expressed during light period, and two carbon fixation genes were up‐regulated in the high‐lipid illuminated cultures, suggesting a linkage between photosynthesis and lipid production. The lipid profile renders Eutreptiella sp. a nutritional prey and valuable source for nutraceuticals, and the biosynthesis pathway documented here will be useful for future research and applications.

Algal lipids are important fuel storage molecules in algae and a currency for energy transfer in the marine food chain as well as materials for biofuel production, but their production and regulation are not well understood in many species including the common coastal phytoplankton Eutreptiella spp. Here, using gas chromatography-tandem mass spectrometry (GC/MS/MS), we discovered 24 types of fatty acids (FAs) in Eutreptiella sp. with a relatively high proportion of long chain unsaturated FAs. The abundances of C16, C18 and saturated FAs decreased when phosphate in the culture medium was depleted. Among the 24 FAs, docosahexaenoic acid (22:6) and eicosapentaenoic acid (20:5) were the most abundant, suggesting that Eutreptiella sp. preferentially invests in the synthesis of very long chain polyunsaturated fatty acids (VLCPFA). Further transcriptomic analysis revealed that Eutreptiella sp. likely synthesizes VLCPFA via Δ8 pathway and uses type I and II fatty acid synthases. Using RT-qPCR, we found that some of the lipid production genes, such as β-ketoacyl-ACP reductase, fatty acid desaturase, acetyl-CoA carboxylase, acyl carrier protein, Δ8 desaturase, and Acyl-ACP thioesterase, were more actively expressed during light period. Besides, two carbon-fixation genes were more highly expressed in the high lipid illuminated cultures, suggesting a linkage between photosynthesis and lipid production.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) are anthropogenic pollutants highly resistant to chemical degradation and readily absorbed by organic tissue. Their persistence in the environment and toxicological threat to mammals prompts swift, reliable methods of analysis. This study outlines a rapid, efficient and sensitive, validated methodology utilizing a simple liquid extraction technique, and subsequent analysis by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) for the determination of PCBs and OCs from dried blood spots. The PCBs and OCs were quantified in whole marine mammal blood spotted on Whatman Protein Saver cards (PSCs) by extracting the analytes into acetonitrile acidified with formic acid, followed by GC-MS/MS analysis. The samples were analyzed in positive electron impact (EI+) ionization mode with the electron energy set to 40 eV to preserve analyte integrity. Fortified blood with the analytes of interest was used for method validation and subsequent sample screening. The recoveries of targeted analytes ranged from 62.5% to 107.8%, with relative standard deviations ranging from 0.09% to 4.6% at a 100 ng center dot mL(-1) concentration level. The method detection limits were from 40.4 ng center dot g(-1) to 179.2 ng center dot g(-1) for the PCBs and 37.6 ng center dot g(-1) to 145.1 ng center dot g(-1) for the OCs. The use of dried blood spots provided for numerous advantages compared to whole blood samples while demonstrating reduced matrix effects and enhanced sample lifespan while retaining analyte sensitivity.

Here, a simple, reliable method for the quantification of the 16 EPA priority polycyclic aromatic hydrocarbons in dried blood spots is outlined using liquid extraction and phospholipid solid-phase sample cleanup coupled with analysis by ultra-performance liquid chromatography with ultraviolet-visible detection. Whole blood spotted on Whatman FTA cards was efficiently quantified by extraction into acidified methanol and passed through a phospholipid solid-phase extraction well plate before injection into a liquid chromatography under reverse-phase conditions. The analyte recoveries in quality control samples ranged from 63.4 to 104.1%, with relative standard deviations from 0.48 to 2.04%. These figures of merit are comparable with measurements in whole blood or serum using similar techniques. The method detection limits were from 45.0ngg(-1) for benzo[g,h,i]perylene to 118.7ngg(-1) for chrysene, with matrix spike recoveries from 64.3 to 99.4%, demonstrating acceptable sensitivity and low matrix interference. With a simple liquid extraction approach and short 16-min liquid chromatography, the dried blood spots were effectively and rapidly analyzed.

The synthesis and photocleavage of quinolinyl methyl ether-protected alcohols is reported in this study. A variety of quinoline methyl chlorides were synthesized, and protection of the various alcohols was performed via a substitution reaction in the presence of a strong base. Photocleavage of the quinolinyl methyl ether moiety proceeded under visible light with the formation of the charged quinolinyl radical intermediate through a single-electron transfer in the presence of a photosensitizer dye leading to the deprotected alcohol in excellent yields. The utility of triethylamine as a sacrificial reductant and d-sorbitol as a radical scavenger were also investigated in this study.

A streamlined method has been developed for the isolation and analysis of polycyclic aromatic hydrocarbons in avian blood cells and plasma utilizing quick, easy, cheap, effective, rugged, and safe extraction in combination with novel phospholipid cleanup technology. A variety of traditional extraction and cleanup techniques have been employed in the preparation and analysis of polycyclic aromatic hydrocarbonsin a variety of matrices; liquid-liquid partitioning, solid-phase extractions, gel permeation chromatography, and column chromatography are all effective techniques, however they are laborious and time consuming processes that require large amounts of solvent. Using quick, easy, cheap, effective, rugged, and safe extraction coupled with phospholipid cleanup, samples can be quickly screened while maintaining high throughput and sensitivity. With a liquid chromatography approach, analysis times may be kept short at 16 min while maintaining high analyte recovery. Recoveries in quality control samples ranged from 70 to 109%, with average surrogate recoveries of 80.6 ± 1.10%. The result of using a quick, easy, cheap, effective, rugged, and safe extraction approach in conjunction with phospholipid cleanup is a methodology that significantly reduces sample preparation time and solvent use while maintaining high sensitivity and reproducibility.

The regioselective cleavage of epoxides using visible light and a catalytic dye is reported in this study as an alternative mild synthetic approach. The epoxide radical anion is generated via visible light in an electron transfer reaction, induced by non-toxic dyes, leading to ring opening and formation of the corresponding alcohol with the hydroxyl group on the less substituted carbon in excellent yields.

Novel, rapid, inexpensive, and simple QuEChERS extraction followed by phospholipid solid phase extraction was successfully developed and validated for the determination of methoprene, resmethrin, bifenthrin, cyhalothrin, and permethrin in lobster and shellfish tissues by gas chromatography-tandem mass spectrometry. This method is equivalent in final sample purity to the traditional gel permeation and open column chromatography sample preparation techniques, but has clear advantages due to reductions in time, labor, solvent use, and can be performed with minimal staff training. The proposed methodology was effectively applied to the analysis of North Atlantic lobster (hepatopancreas and muscle) and shellfish tissue. The linearity of the calibration curves for all analytes were R-2 >0.9991. The surrogate recoveries were 98.2 +/- 18.0%, while the target compound recoveries, for fortified samples, were in the range of 62.0%-128.8% with RSD values <17.2% for all compounds. The detection limits for the analytes ranged from 0.0056 mu g/g to 0.76 mu g/g with 84.4-119.5% accuracy and relative standard deviations less than 3.77%.

Acetonitrile is a commonly used solvent in both industry and research. The treatment of acetonitrile wastes in dilute aqueous solutions with visible light offers advantages to chemical treatment and ultraviolet (UV) irradiation. This study presents the degradation of acetonitrile via a photoinduced electron transfer reaction in the presence of a photosensitizer (dye) and a sacrificial reductant under visible light. Acetonitrile photodegradation (photoreduction) was investigated utilizing a variety of sacrificial reductants and photosensitizers. Optimal results were observed in the presence of methylene green and tri-isopropanolamine with a decrease of acetonitrile in solution to 86% in 24hours. The only photoreaction product observed was acetaldehyde and a plausible mechanism for the photochemical degradation of acetonitrile is proposed.

A quantification method was developed for the determination of dioctyl sulfosuccinate sodium salt (DOSS) in avian egg samples based on a QuEChERS extraction technique followed by UPLC-MS/MS analysis. DOSS is an anionic surfactant that is part of the Corexit((R)) 9500 dispersive mixture that prevents the formation of oil slicks on water bodies. It was extensively used when the Deepwater Horizon rig exploded and a large amount of crude oil was released into the Gulf of Mexico. QuEChERS provided a simple, effective and time saving sample preparation method prior to analysis without reducing analytical sensitivity and became an excellent substitute to lengthy traditional extraction methods. Weak anionic exchange cleanup significantly reduced matrix effects and improved analyte sensitivity. Ultra-performance liquid chromatography provided an effective separation method, while MS/MS provided the necessary selectivity and increased sensitivity. Our method achieved baseline separation of DOSS, surrogate (sodium octyl sulfate - d17) and the internal standard (sodium dioctyl sulfate - d25), with limits of detection (LOD) and limits of quantitation (LOQ) for DOSS being 260 and 500pg/mL, respectively. Quality control recoveries were 70.5 +/- 7.3% (mean +/- standard deviation, n=3) for the laboratory control sample and 72.4 +/- 4.9% (n=3) for the matrix spike. The extraction efficiency was monitored by adding surrogate compound to every sample with recoveries of 104.6 +/- 14.1 for SDS-d1 and 81.8 +/- 6.8 for SOS-d17. Currently, limited peer reviewed scientific data are reported on the effects of oil dispersants on the environment. Our analytical method for the determination of DOSS in avian egg matrix can be used to provide reliable data on the fate and effects of DOSS in biological systems.

This article reports modern and effective sample preparations designed for rapid screening of large number of samples of avian blood utilizing liquid–liquid extraction and egg using QuEChERS techniques. A UPLC-UV methodology for determination of polycyclic aromatic hydrocarbons (PAHs) on the afore mentioned matrices was developed based on samples associated with the Gulf of Mexico after the Deep Water Horizon oil spill. Both sample preparation methods provided comparable recovery results for 15 EPA priority pollutants PAHs. A UPLC system equipped with photo-diode array detector and tandem mass spectrometer was utilized for the quantification and confirmation of the analytes, respectively. The surrogate compound, naphthalene-d8, was used to monitor the extraction efficiency and chrysene-d12 as the quantitative internal standard. The recoveries of the analytes in the quality control (QC) samples were 65–110% with surrogate recoveries greater than 80%, whereas for the avian egg tissue recoveries were 43–100% and greater than 80% for the quality control (QC) samples and surrogate, respectively.

A major die-off of the American lobster (Homarus americanus) population in Long Island Sound (LIS) occurred in 1999, involving multiple causes, including increases of temperatures, decreasing oxygen concentrations, and pollutants. Other possible affectors were stress to their immune system, microbial population changes, which may have induced shell disease, water acidification, and insecticides. We examined LIS alkylphenol pollution. Alkylphenols, alkylphenol ethoxylates, and bisphenol A (BPA) are produced in excessive amounts, with BPA estimated at 8 billion pounds per year (1 lb = 0.453 kg). Sixty percent of alkylphenols enter the marine environment and have estrogenic endocrine-disrupting effects on vertebrates. We found multiple effects of alkylphenols on lobsters, on larval survival, molting and postlarval molting, shell hardening, and interference in metamorphosis causing larval–juvenile intermediates. We also found evidence for a basic molecular mechanism of action for alkylphenols through juvenile hormone (JH) and ecdysone receptors. Alkylphenols appear to have contributed to the decrease in the LIS lobster population. We recommend remediation, reducing, or eliminating alkylphenols from the marine environment to protect lobsters as well as other organisms.

ABSTRACT Endocrine-disrupting pollutants in rivers and oceans represent a poorly understood but potentially serious threat to the integrity of aquatic and coastal ecosystems. We surveyed the hemolymph of lobsters from across southern New England and adjacent offshore areas for 3 endocrine-disrupting alkylphenols. We found all 3 compounds in hemolymph from every year and almost every region sampled. Prevalence of contamination varied significantly between regions, ranging from 45% of lobsters from southern Massachusetts to 17% of lobsters from central Long Island Sound. Mean contamination levels varied significantly as a function of region, year sampled, and collection trip, and were highest overall in lobsters from western Long Island Sound and lowest in lobsters from central Long Island Sound. Surprisingly, lobsters from offshore areas were not less contaminated than lobsters from inshore areas. Contamination levels also did not vary as a function of lobster size or shell disease signs. Contaminated lobsters held in the laboratory did not retain alkylphenols, suggesting that hemolymph contamination levels represent recent, rather than long-term, exposure. Our data set is the first, to our knowledge, to survey endocrine-disrupting contaminants in a population across such a broad temporal and spatial scale. We show that alkylphenol contamination is a persistent, widespread, but environmentally heterogeneous problem in lobster populations in southern New England and adjacent offshore areas. Our work raises serious questions about the prevalence and accumulation of these endocrine-disrupting pollutants in an important fishery species.

A countercurrent liquid/liquid phase biodiesel reactor achieved 99% triglyceride to methyl ester conversion at the same time as separating 90% of the produced glycerin. However, a low inverse sensitivity of the conversion to the glycerin separation efficiency led to biodiesel that did not meet ASTM quality standards in previous work. A distributed methanol injection strategy is demonstrated herein to improve reactor performance, yielding ASTM quality biodiesel and 90% separation efficiencies. Preliminary data on feed rate changes yields counterintuitive results where conversion increases as feed rate increases. A model that assumes equilibrium between the reacting oil phase and the settling glycerol phase simulates the experimental results and provides insight into the reactor behavior. (c) 2012 Elsevier Ltd. All rights reserved.

Cannabis sativa Linn, known as industrial hemp, was utilized for biodiesel production in this study. Oil from hemp seed was converted to biodiesel through base-catalyzed transesterification. The conversion is greater than 99.5% while the product yield is 97%. Several ASTM tests for biodiesel quality were implemented on the biodiesel product, including acid number, sulfur content, flash point, kinematic viscosity, and free and total glycerin content. In addition, the biodiesel has a low cloud point (−5°C) and kinematic viscosity (3.48mm2/s). This may be attributed to the high content of poly-unsaturated fatty acid of hemp seed oil and its unique 3:1 ratio of linoleic to α-linolenic acid.

The following study analyzes the performance of a continuous flow biodiesel reactor/separator. The reactor achieves high conversion of vegetable oil triglycerides to biodiesel while simultaneously separating co-product glycerol. The influence of the flow direction, relative to the gravity vector, on the reactor performance was measured. Reactor performance was assessed by both the conversion of vegetable oil triglycerides to biodiesel and the separation efficiency of removing the co-product glycerol. At slightly elevated temperatures of 40-50 °C, an overall feed of 1.2 L/min, a 6:1 M ratio of methanol to vegetable oil triglycerides, and a 1–1.3 wt.% potassium hydroxide catalyst loading, the reactor converted more than 96% of the pretreated waste vegetable oil to biodiesel. The reactor also separated 36–95% of the glycerol that was produced. Tilting the reactor away from the vertical direction produced a large increase in glycerol separation efficiency and only a small decrease in conversion.