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Antimicrobial drugs and coccidiostat compounds are commonly used in poultry farming. These compounds are subsequently excreted and released into the environment via broiler litter (BL) and can re-enter the food chain as fertilizer or animal feed. Such residue in animal feed can encourage the appearance of antibiotic-resistant bacteria as well as toxicity. Most analytical methods used to identify and quantitate these drug residues are traditional, and are specific to some antimicrobials and present limitations in assessing complex matrixes like BL. The aim of this study was to develop a multi-residue analytic method for assessing 30 antimicrobial drugs and coccidiostats associated with BL. We investigated the presence and the effects of biotic stack treatment on the degradation of drug residue in BL. Liquid-liquid extraction (LLE) and solid phase extraction (SPE) were replaced by Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) clean-up steps and detected by liquid chromatography mass spectrometry (LC/MS/MS). Results show that a wide spectrum of residues were detected from 0.4 to 8.9 mg kg−1. Following lab-scale stacking treatment, tilmicosin and eight coccidiostats persisted in BL (26–100%). This research supports the need for better understanding, regulation, and management of the use of BL that might carry a high risk of residue drugs. [ABSTRACT FROM AUTHOR]

Several compounds with different physical properties are present in foods, biological components, and environmental samples, and there are cases in which these must be analyzed simultaneously. However, it is difficult to extract compounds with different physical properties from the same sample using a single method. In the present study, we examined the optimal conditions for the QuEChERS extraction of several kinds of compounds from orange juice using design of experiments (DoE) and response surface methodology (RSM) to determine the optimal ratio of organic solvent to sodium chloride. We determined the optimal extraction conditions, which were within the design space, using 100% tetrahydrofuran (THF) as the extraction organic solvent and NaCl:MgSO4 = 75:25 as the salt. The developed LC/MS/MS method using QuEChERS extraction achieved specific detection and precise quantification. Finally, we measured the polyphenols, sterols, and carotenoids in citrus juice using the optimized QuEChERS extraction method before LC/MS/MS analysis. Most of the analytes were quantifiable in orange juice. The optimized method achieved ease of operation, the extraction of analytes from food samples in a short time (within 30 min), minimization of analytical residues, and reliability. The DoE and RSM approach may contribute to better optimization of the extraction conditions for the lowest number of experiments. [ABSTRACT FROM AUTHOR]

Panax notoginseng (Burk) F. H. Chen is a traditional Chinese medicinal and edible plant. However, Panax notoginseng flower (PNF) is rarely used. Therefore, the purpose of this study was to explore the main saponins and the anti-inflammatory bioactivity of PNF saponins (PNFS). We explored the regulation of cyclooxygenase 2 (COX–2), a key mediator of inflammatory pathways, in human keratinocyte cells treated with PNFS. A cell model of UVB-irradiation-induced inflammation was established to determine the influence of PNFS on inflammatory factors and their relationship with LL–37 expression. An enzyme-linked immunosorbent assay and Western blotting analysis were used to detect the production of inflammatory factors and LL37. Finally, liquid chromatography–tandem mass spectrometry was employed to quantify the main active components (ginsenosides Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, and notoginsenoside R1) in PNF. The results show that PNFS substantially inhibited COX–2 activity and downregulated the production of inflammatory factors, indicating that they can be used to reduce skin inflammation. PNFS also increased the expression of LL-37. The contents of ginsenosides Rb1, Rb2, Rb3, Rc, and Rd in PNF were much higher than those of Rg1, and notoginsenoside R1. This paper provides data in support of the application of PNF in cosmetics. [ABSTRACT FROM AUTHOR]

Ceftobiprole is a novel β-lactam antibiotic, active against methicillin-resistant Staphylococcus aureus, vancomycin-resistant S. aureus and penicillin-resistant Streptococcus pneumoniae. To artificially generate potential degradation products (DPs) of ceftobiprole that may be formed under relevant storage conditions, acidic, alkaline, oxidative, photolytic and thermolytic stress tests were performed in both solution and solid state. A novel selective HPLC method was developed for the separation of ceftobiprole from its DPs and synthesis by-products (SBPs) using Kinetex Biphenyl column, ammonium acetate buffer pH 5.8 and acetonitrile. The kinetic studies demonstrated the low stability of ceftobiprole in alkaline solution, in the presence of an oxidising agent and under irradiation with near UV. In the solid state, ceftobiprole underwent oxidation when the powder was irradiated with visible light and UV. Based on mass spectroscopic analysis, 13 new structural formulas of SBPs and DPs were proposed, along with molecular formulas for three other DPs obtained in solution and four oxidative DPs characteristic of solid-state degradation. [ABSTRACT FROM AUTHOR]

Sorghum malts, which are important ingredients in traditional fermented beverages, are commonly infected by mycotoxigenic fungi and mycotoxins may transfer into the beverages, risking consumers’ health. Liquid chromatography–tandem mass spectrometry was used to determine variation of fungal metabolites in 81 sorghum malts processed for brewing of Namibian beverages, otombo (n = 45) and omalodu (n = 36). Co-occurrence of European Union (EU)-regulated mycotoxins, such as patulin, aflatoxins (B1, B2, and G2), and fumonisins (B1, B2, and B3) was detected in both malts with a prevalence range of 2–84%. Aflatoxin B1 was quantified in omalodu (44%) and otombo malts (14%), with 20% of omalodu malts and 40% of otombo malts having levels above the EU allowable limit. Fumonisin B1 was quantified in both omalodu (84%) and otombo (42%) malts. Emerging mycotoxins, aflatoxin precursors, and ergot alkaloids were quantified in both malts. Notably, 102 metabolites were quantified in both malts, with 96% in omalodu malts and 93% in otombo malts. An average of 48 metabolites were quantified in otombo malts while an average of 67 metabolites were quantified in omalodu malts. The study accentuates the need to monitor mycotoxins in sorghum malts intended for brewing and to determine their fate in the beverages. [ABSTRACT FROM AUTHOR]

This study aimed to assess the occurrence of toxigenic fungi and mycotoxin contamination in stored wheat grains by using advanced molecular and analytical techniques. A multiplex polymerase chain reaction (PCR) strategy was established for rapid identification of mycotoxigenic fungi, and an improved analytical method was developed for simultaneous multi-mycotoxin determination in wheat grains by liquid chromatography-tandem mass spectrometry (LC/MS/MS) without the need for any clean-up. The optimized multiplex PCR method was highly specific in detecting fungal species containing species-specific and mycotoxin metabolic pathway genes. The method was applied for evaluation of 34 wheat grain samples collected from storage warehouses for the presence of mycotoxin-producing fungi, and a few samples were found positive for Fusarium and Aspergillus species. Further chemical analysis revealed that 17 samples contained mycotoxins above the level of detection, but only six samples were found to be contaminated over the EU regulatory limits with at least one mycotoxin. Aflatoxin B1, fumonisins, and deoxynivalenol were the most common toxins found in these samples. The results showed a strong correlation between the presence of mycotoxin biosynthesis genes as analyzed by multiplex PCR and mycotoxin detection by LC/MS/MS. The present findings indicate that a combined approach might provide rapid, accurate, and sensitive detection of mycotoxigenic species and mycotoxins in wheat grains. [ABSTRACT FROM AUTHOR]

An improved analytical method compared with conventional ones was developed for simultaneous determination of 13 mycotoxins (deoxynivalenol, nivalenol, 3-acetylnivalenol, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, T-2, HT-2, zearalenone, and ochratoxin A) in cereal grains by liquid chromatography-tandem mass spectrometry (LC/MS/MS) after a single immunoaffinity column clean-up. The method showed a good linearity, sensitivity, specificity, and accuracy in mycotoxin determination by LC/MS/MS. The levels of 13 mycotoxins in 5 types of commercial grains (brown rice, maize, millet, sorghum, and mixed cereal) from South Korea were determined in a total of 507 cereal grains. Mycotoxins produced from Fusarium sp. (fumonisins, deoxynivalenol, nivalenol, and zearalenone) were more frequently (more than 5%) and concurrently detected in all cereal grains along with higher mean levels (4.3-161.0 ng/g) in positive samples than other toxins such as aflatoxins and ochratoxin A (less than 9% and below 5.2 ng/g in positive samples) from other fungal species. [ABSTRACT FROM AUTHOR]

Japanese scallops, Patinopecten yessoensis, were fed with the toxic dinoflagellate Dinophysis fortii to elucidate the relative magnitude of assimilation, accumulation, and metabolism of diarrhetic shellfish toxins (DSTs) and pectenotoxins (PTXs). Three individual scallops were separately exposed to cultured D. fortii for four days. The average cell number of D. fortii assimilated by each individual scallop was 7.7 × 105. Dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2) and their metabolites were analyzed by liquid chromatography tandem mass spectrometry (LC/MS/MS) and the toxin content in individual tissues (digestive gland, adductor muscle, gill, gonad, mantle, and the others), feces and the seawater medium were quantified. Toxins were almost exclusively accumulated in the digestive gland with only low levels being detected in the gills, mantles, gonads, and adductor muscles. DTX1 and PTX2 were the dominant toxins in the D. fortii cells fed to the scallops, whereas the dominant toxins detected in the digestive gland of scallops were PTX6 and esterified acyl-O-DTX1 (DTX3). In other tissues PTX2 was the dominant toxin observed. The ratio of accumulated to assimilated toxins was 21%-39% and 7%-23% for PTXs and DTXs respectively. Approximately 54%-75% of PTX2 and 52%-70% of DTX1 assimilated by the scallops was directly excreted into the seawater mainly without metabolic transformation. [ABSTRACT FROM AUTHOR]

Geissoschizine methyl ether (GM) is an indole alkaloid found in Uncaria hook, which is a galenical constituent of yokukansan, a traditional Japanese medicine. GM has been identified as the active component responsible for anti-aggressive effects. In this study, the metabolic profiling of GM in rat and human liver microsomes was investigated. Thirteen metabolites of GM were elucidated and identified using a high-performance liquid chromatography with tandem mass spectrometry method, and their molecular structures were proposed on the basis of the characteristics of their precursor ions, product ions, and chromatographic retention times. There were no differences in the metabolites between the rat and human liver microsomes. Among the 13 identified metabolites, there were two demethylation metabolites, one dehydrogenation metabolite, three methylation metabolites, three oxidation metabolites, two water-adduct metabolites, one di-demethylation metabolite, and one water-adduct metabolite followed by oxidation. The metabolic pathways of GM were proposed on the basis of this study. This study will be helpful in understanding the metabolic routes of GM and related Uncaria hook alkaloids, and provide useful information on the pharmacokinetics and pharmacodynamics. This is the first report that describes the separation and identification of GM metabolites in rat and human liver microsomes. [ABSTRACT FROM AUTHOR]

Lysophosphatidic acid (LPA) is the umbrella term for lipid signaling molecules that share structural homology and activate the family of LPA receptors. Farnesyl Pyrophosphate (FPP) is commonly known as an intermediate in the synthesis of steroid hormones; however, its function as a signaling lipid is beginning to be explored. FPP was recently shown to an activator of the G-protein coupled receptor 92 (also known as LPA5) of the calcium channel TRPV3. The LPA receptors (including GPR92) are associated with the signal transduction of noxious stimuli, however, very little is known about the distribution of their signaling ligands (LPAs and FPP) in the brain. Here, using HPLC/MS/MS, we developed extraction and analytical methods for measuring levels of FPP and 4 species of LPA (palmitoyl, stearoyl, oleoyl and arachidonoyl-sn-glycerol-3 phosphate) in rodent brain. Relative distributions of each of the five compounds was significantly different across the brain suggesting divergent functionality for each as signaling molecules based on where and how much of each is being produced. Brainstem, midbrain, and thalamus contained the highest levels measured for each compound, though none in the same ratios while relatively small amounts were produced in cortex and cerebellum. These data provide a framework for investigations into functional relationships of these lipid ligands in specific brain areas, many of which are associated with the perception of pain. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) and its deoxy analogs, 5-deoxyTTX, 11-deoxyTTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX, were quantified in the tissues of three female and three male specimens of the marine puffer fish, Fugu niphobles, from the southern coast of Korea, and in the whole body of the brackishwater puffer fishes, Tetraodon nigroviridis (12 specimens) and Tetrodon biocellatus (three specimens) from Southeast Asia using LC/MS in single ion mode (SIM). Identification of these four deoxy analogs in the ovarian tissue of F. niphobles were further confirmed by LC/MS/MS. TTX and 5,6,11-trideoxyTTX were detected in all three puffer fish species as the major TTX analogs, similar to Japanese Fugu pardalis. While 6,11-dideoxyTTX was also found to be a major analog in almost all tissues of Korean F. niphobles, this analog was minor in the two Tetraodon species and Japanese F. pardalis. Among the tissues of F. niphobles, the concentrations of TTXs were highest in the ovaries (female) and skin (female and male). [ABSTRACT FROM AUTHOR]

Okadaic acid (OA) and its main structural analogs dinophysistoxin-1 (DTX1) and dinophysistoxin-2 (DTX2) are marine lipophilic phycotoxins distributed worldwide that can be accumulated by edible shellfish and can cause diarrheic shellfish poisoning (DSP). In order to study their toxicokinetics, mice were treated with different doses of OA, DTX1, or DTX2 and signs of toxicity were recorded up to 24 h. Toxin distribution in the main organs from the gastrointestinal tract was assessed by liquid chromatography-mass spectrometry (LC/MS/MS) analysis. Our results indicate a dose-dependency in gastrointestinal absorption of these toxins. Twenty-four hours post-administration, the highest concentration of toxin was detected in the stomach and, in descending order, in the large intestine, small intestine, and liver. There was also a different toxicokinetic pathway between OA, DTX1, and DTX2. When the same toxin doses are compared, more OA than DTX1 is detected in the small intestine. OA and DTX1 showed similar concentrations in the stomach, liver, and large intestine tissues, but the amount of DTX2 is much lower in all these organs, providing information on DSP toxicokinetics for human safety assessment. [ABSTRACT FROM AUTHOR]

d-amino acids have distinct roles from their l-enantiomer. In particular, some d-amino acids function as agonists or antagonists of neuronal receptors and are involved in higher brain functions. Thus, it is important to precisely measure the levels of these amino acid enantiomers in cells and tissues. Various quantification methods have been developed for measurements of chiral amino acids. However, each method has advantages and disadvantages. Additionally, measuring the amino acid enantiomers in crude biological samples requires a higher selectivity. In this study, we developed a quantification method for amino acid enantiomers using derivatization with Nα-(5-Fluoro-2,4-dinitrophenyl)-l-leucinamide (l-FDLA) followed by liquid chromatography–tandem mass spectrometry (LC/MS/MS) with a conventional reversed-phase column. We simultaneously identified 10 chiral amino acids. Furthermore, we applied this method to investigate murine tissue samples and examined the effect of aging on the amino acid levels in aged brain regions. We found that aging decreased the levels of both d-serine and d-aspartate in the hippocampus. In addition, d-Phenylalanine in the thalamus significantly increased with age. In conclusion, our method is suitable for the quantification of the d-amino acids in crude biological samples and may contribute to elucidating the biological roles of chiral amino acids. [ABSTRACT FROM AUTHOR]

Fast and reliable workflows are needed to quantitate microcystins (MCs), a ubiquitous class of hepatotoxic cyanotoxins, so that the impact of human and environmental exposure is assessed quickly and minimized. Our goal was to develop a high-throughput online concentration liquid chromatography tandem mass spectrometry (LC/MS/MS) workflow to quantitate the 12 commercially available MCs and nodularin in surface and drinking waters. The method run time was 8.5 min with detection limits in the low ng/L range and minimum reporting levels between 5 and 10 ng/L. This workflow was benchmarked by determining the prevalence of MCs and comparing the Adda-ELISA quantitation to our new workflow from 122 samples representing 31 waterbodies throughout Michigan. The frequency of MC occurrence was MC-LA > LR > RR > D-Asp3-LR > YR > HilR > WR > D-Asp3-RR > HtyR > LY = LW = LF, while MC-RR had the highest concentrations. MCs were detected in 33 samples and 13 of these samples had more than 20% of their total MC concentration from MCs not present in US Environmental Protection Agency (US EPA) Method 544. Furthermore, seasonal deviations between the LC/MS/MS and Adda-ELISA data suggest Adda-ELISA cross-reacts with MC degradation products. This workflow provides less than 24-h turnaround for quantification and also identified key differences between LC/MS/MS and ELISA quantitation that should be investigated further. [ABSTRACT FROM AUTHOR]

Diarrhetic shellfish toxins (DSTs) are a group of phycotoxins that include okadaic acid (OA)/dinophysistoxin (DTX) analogues. At present, detailed data on the distribution of DST is insufficient, and studies of the appropriate sample sizes are lacking. This study investigated the DST frequency distribution in scallops and mussels by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and a resampling analysis of existing data was carried out. The DST population-interval and the necessary sample size were also estimated. DSTs are localized in the scallop digestive-gland, and the DST concentrations in scallops were water-depth-dependent. DST concentrations in scallops and mussels showed normal distributions, but mussels tended to contain more DSTs than scallops. In the statistical resampling analysis of the acquired data on scallops and mussels, especially that using the bootstrap method, sample size was difficult to estimate when the DST variation was large. Although the DST population-interval could be statistically estimated from the sample standard deviation of three samples, the sample size corresponded to the risk management level, and the use of 13 or more samples was preferable. The statistical methods used here to analyze individual contents and estimate population content-intervals could be applied in various situations and for shellfish toxins other than DSTs. [ABSTRACT FROM AUTHOR]

Bacterial resistance to antibiotics and the disruption of beneficial microbiota are key problems in contemporary medicine and make the search for new, more efficient infection treatment strategies among the most important tasks in medicine. Multicomponent plant-derived preparations with mild antibacterial activity created by many simultaneous mechanisms together with anti-inflammatory, innate immune and regenerative capacity-stimulating properties are good candidates for this therapy, and proanthocyanidins are among the most promising compounds of this sort. In this study, we have isolated proanthocyanidins from Pelargonium sidoides DC root extract and characterized and compared the composition, antioxidant properties and antibacterial activity of the proanthocyanidin fraction with those of the whole extract. The results revealed that proanthocyanidins had significantly stronger antioxidant capacity compared to the root extract and exhibited a unique antibacterial action profile that selectively targets Gram-negative keystone periodontal and peri-implant pathogenic strains, such as Porphyromonas gingivalis, while preserving the viability of beneficial oral commensal Streptococcus salivarius. The finding suggests that proanthocyanidins from Pelargonium sidoides root extract are good candidates for the prolonged and harmless treatment of infectious diseases. [ABSTRACT FROM AUTHOR]

An improved analytical method compared with conventional ones was developed for simultaneous determination of 13 mycotoxins (deoxynivalenol, nivalenol, 3-acetylnivalenol, aflatoxin B₁, aflatoxin B₂, aflatoxin G₁, aflatoxin G₂, fumonisin B₁, fumonisin B₂, T-2, HT-2, zearalenone, and ochratoxin A) in cereal grains by liquid chromatography-tandem mass spectrometry (LC/MS/MS) after a single immunoaffinity column clean-up. The method showed a good linearity, sensitivity, specificity, and accuracy in mycotoxin determination by LC/MS/MS. The levels of 13 mycotoxins in 5 types of commercial grains (brown rice, maize, millet, sorghum, and mixed cereal) from South Korea were determined in a total of 507 cereal grains. Mycotoxins produced from Fusarium sp. (fumonisins, deoxynivalenol, nivalenol, and zearalenone) were more frequently (more than 5%) and concurrently detected in all cereal grains along with higher mean levels (4.3-161.0 ng/g) in positive samples than other toxins such as aflatoxins and ochratoxin A (less than 9% and below 5.2 ng/g in positive samples) from other fungal species.

Japanese scallops, Patinopecten yessoensis, were fed with the toxic dinoflagellate Dinophysis fortii to elucidate the relative magnitude of assimilation, accumulation, and metabolism of diarrhetic shellfish toxins (DSTs) and pectenotoxins (PTXs). Three individual scallops were separately exposed to cultured D. fortii for four days. The average cell number of D. fortii assimilated by each individual scallop was 7.7 × 10⁵. Dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2) and their metabolites were analyzed by liquid chromatography tandem mass spectrometry (LC/MS/MS) and the toxin content in individual tissues (digestive gland, adductor muscle, gill, gonad, mantle, and the others), feces and the seawater medium were quantified. Toxins were almost exclusively accumulated in the digestive gland with only low levels being detected in the gills, mantles, gonads, and adductor muscles. DTX1 and PTX2 were the dominant toxins in the D. fortii cells fed to the scallops, whereas the dominant toxins detected in the digestive gland of scallops were PTX6 and esterified acyl-O-DTX1 (DTX3). In other tissues PTX2 was the dominant toxin observed. The ratio of accumulated to assimilated toxins was 21%-39% and 7%-23% for PTXs and DTXs respectively. Approximately 54%-75% of PTX2 and 52%-70% of DTX1 assimilated by the scallops was directly excreted into the seawater mainly without metabolic transformation.

Lysophosphatidic acid (LPA) is the umbrella term for lipid signaling molecules that share structural homology and activate the family of LPA receptors. Farnesyl Pyrophosphate (FPP) is commonly known as an intermediate in the synthesis of steroid hormones; however, its function as a signaling lipid is beginning to be explored. FPP was recently shown to an activator of the G-protein coupled receptor 92 (also known as LPA5) of the calcium channel TRPV(3). The LPA receptors (including GPR92) are associated with the signal transduction of noxious stimuli, however, very little is known about the distribution of their signaling ligands (LPAs and FPP) in the brain. Here, using HPLC/MS/MS, we developed extraction and analytical methods for measuring levels of FPP and 4 species of LPA (palmitoyl, stearoyl, oleoyl and arachidonoyl-sn-glycerol-3 phosphate) in rodent brain. Relative distributions of each of the five compounds was significantly different across the brain suggesting divergent functionality for each as signaling molecules based on where and how much of each is being produced. Brainstem, midbrain, and thalamus contained the highest levels measured for each compound, though none in the same ratios while relatively small amounts were produced in cortex and cerebellum. These data provide a framework for investigations into functional relationships of these lipid ligands in specific brain areas, many of which are associated with the perception of pain.

Tetrodotoxin (TTX) and its deoxy analogs, 5-deoxyTTX, 11-deoxyTTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX, were quantified in the tissues of three female and three male specimens of the marine puffer fish, Fugu niphobles, from the southern coast of Korea, and in the whole body of the brackishwater puffer fishes, Tetraodon nigroviridis (12 specimens) and Tetrodon biocellatus (three specimens) from Southeast Asia using LC/MS in single ion mode (SIM). Identification of these four deoxy analogs in the ovarian tissue of F. niphobles were further confirmed by LC/MS/MS. TTX and 5,6,11-trideoxyTTX were detected in all three puffer fish species as the major TTX analogs, similar to Japanese Fugu pardalis. While 6,11-dideoxyTTX was also found to be a major analog in almost all tissues of Korean F. niphobles, this analog was minor in the two Tetraodon species and Japanese F. pardalis. Among the tissues of F. niphobles, the concentrations of TTXs were highest in the ovaries (female) and skin (female and male).

Diverse species of cyanobacteria have recently been discovered to produce the neurotoxic non-protein amino acid beta-methylamino-L-alanine (BMAA). In Guam, BMAA has been studied as a possible environmental toxin in the diets of indigenous Chamorro people known to have high levels of Amyotrophic Lateral Sclerosis/ Parkinsonism Dementia Complex (ALS/PDC). BMAA has been found to accumulate in brain tissues of patients with progressive neurodegenerative illness in North America. In Guam, BMAA was found to be produced by endosymbiotic cyanobacteria of the genus Nostoc which live in specialized cycad roots. We here report detection of BMAA in laboratory cultures of a free-living marine species of Nostoc. We successfully detected BMAA in this marine species of Nostoc with five different methods: HPLC-FD, UPLC-UV, Amino Acid Analyzer, LC/MS, and Triple Quadrupole LC/MS/MS. This consensus of five different analytical methods unequivocally demonstrates the presence of BMAA in this marine cyanobacterium. Since protein-associated BMAA can accumulate in increasing levels within food chains, it is possible that biomagnification of BMAA could occur in marine ecosystems similar to the biomagnification of BMAA in terrestrial ecosystems. Production of BMAA by marine cyanobacteria may represent another route of human exposure to BMAA. Since BMAA at low concentrations causes the death of motor neurons, low levels of BMAA exposure may trigger motor neuron disease in genetically vulnerable individuals.