Untargeted LC-HRMS applied to microcystin-producing cyanobacterial cultures for the evaluation of the efficiency of chlorine-based treatments commonly used for water potabilization.

Cyanobacteria in water supplies are considered an emerging threat, as some species produce toxic metabolites, cyanotoxins, of which the most widespread and well-studied are microcystins. Consumption of contaminated water is a common exposure route to cyanotoxins, making the study of cyanobacteria in drinking waters a priority to protect public health. In drinking water treatment plants, pre-oxidation with chlorinated compounds is widely employed to inhibit cyanobacterial growth, although concerns on its efficacy in reducing cyanotoxin content exists.

Dereplication of Gambierdiscusbalechii extract by LC-HRMS and in vitro assay: First description of a putative ciguatoxin and confirmation of 44-methylgambierone.

Marine toxins have a significant impact on seafood resources and human health. Up to date, mainly based on bioassays results, two genera of toxic microalgae, Gambierdiscus and Fukuyoa have been hypothesized to produce a suite of biologically active compounds, including maitotoxins (MTXs) and ciguatoxins (CTXs) with the latter causing ciguatera poisoning (CP) in humans. The global ubiquity of these microalgae and their ability to produce (un-)known bioactive compounds, necessitates strategies for screening, identifying, and reducing the number of target algal species and compounds selected for structural elucidation.

Untargeted and targeted LC-MS and data processing workflow for the comprehensive analysis of oligopeptides from cyanobacteria.

Cyanobacteria produce a plethora of structurally diverse bioactive secondary metabolites, including cyanotoxins which pose a serious threat to humans and other living organisms worldwide. Currently, a wide variety of mass spectrometry-based methods for determination of microcystins (MCs), the most commonly occurring and studied class of cyanotoxins, have been developed and employed for research and monitoring purposes. The scarcity of commercially available reference materials, together with the ever-growing range of mass spectrometers and analytical approaches, make the accuracy of quantitative analyses a critical point to be carefully investigated in view of a reliable risk evaluation.

Toward Isolation of Palytoxins: Liquid Chromatography Coupled to Low- or High-Resolution Mass Spectrometry for the Study on the Impact of Drying Techniques, Solvents and Materials.

Palytoxin (PLTX) and its congeners are emerging toxins held responsible for a number of human poisonings following the inhalation of toxic aerosols, skin contact, or the ingestion of contaminated seafood. Despite the strong structural analogies, the relative toxic potencies of PLTX congeners are quite different, making it necessary to isolate them individually in sufficient amounts for toxicological and analytical purposes. Previous studies showed poor PLTX recoveries with a dramatic decrease in PLTX yield throughout each purification step.

Improving in vitro ciguatoxin and brevetoxin detection: selecting neuroblastoma (Neuro-2a) cells with lower sensitivity to ouabain and veratridine (OV-LS).

Marine biotoxins accumulating in seafood products pose a risk to human health. These toxins are often potent in minute amounts and contained within complex matrices; requiring sensitive, reliable, and robust methods for their detection. The mouse neuroblastoma (Neuro-2a) cytotoxicity assay (N2a-assay) is a sensitive, high-throughput, in vitro method effective for detecting sodium channel-specific marine biotoxins.

CyanoMetDB, a comprehensive public database of secondary metabolites from cyanobacteria.

Harmful cyanobacterial blooms, which frequently contain toxic secondary metabolites, are reported in aquatic environments around the world. More than two thousand cyanobacterial secondary metabolites have been reported from diverse sources over the past fifty years. A comprehensive, publically-accessible database detailing these secondary metabolites would facilitate research into their occurrence, functions and toxicological risks.

Development of a data dependent acquisition-based approach for the identification of unknown fast-acting toxins and their ester metabolites.

Phycotoxins in the marine food-web represent a serious threat to human health. Consumption of contaminated shellfish and/or finfish poses risk to consumer safety: several cases of toxins-related seafood poisoning have been recorded so far worldwide. Cyclic imines are emerging lipophilic toxins, which have been detected in shellfish from different European countries.

HPLC-Based Analysis of Impurities in Sapropterin Branded and Generic Tablets.

This work was aimed at the definition of a chromatographic method able to separate and quantify impurities present in sapropterin-containing drugs during an accelerated stability study. The chromatographic method was applied to the orphan drug Kuvan and to its corresponding generic sapropterin Dipharma (Diterin), both of which are approved for the treatment of hyperphenylalaninemia-induced symptoms. The two products tested had a similar manufacture date and both had an approved stability shelf-life of three years.

Exploring the Photodynamic Properties of Two Antiproliferative Benzodiazopyrrole Derivatives.

The identification of molecules whose biological activity can be properly modulated by light is a promising therapeutic approach aimed to improve drug selectivity and efficacy on the molecular target and to limit the side effects compared to traditional drugs. Recently, two photo-switchable diastereomeric benzodiazopyrrole derivatives and have been reported as microtubules targeting agents (MTAs) on human colorectal carcinoma p53 null cell line (HCT 116 p53-/-). Their IC was enhanced upon Light Emitting Diode (LED) irradiation at 435 nm and was related to their form.

Massive Occurrence of the Harmful Benthic Dinoflagellate cf. in the Eastern Adriatic Sea.

In September 2015, a massive occurrence of the species was recorded in central Adriatic Kaštela Bay. In order to taxonomically identify the species responsible for this event and determine their toxin profile, cells collected in seawater and from benthic macroalgae were analyzed. Conservative taxonomic methods (light microscopy and SEM) and molecular methods (PCR-based assay) allowed the identification of the species cf.

Role of temperature and nutrients on the growth and toxin production of Prorocentrum hoffmannianum (Dinophyceae) from the Florida Keys.

The benthic dinoflagellate Prorocentrum hoffmannianum M.A. Faust is typical of tropical warm waters and produces biotoxins responsible for diarrhetic shellfish poisoning (DSP).

Structural studies and biological evaluation of T30695 variants modified with single chiral glycerol-T reveal the importance of LEDGF/p75 for the aptamer anti-HIV-integrase activities.

Some G-quadruplex (GQ) forming aptamers, such as T30695, exhibit particularly promising properties among the potential anti-HIV drugs. T30695 G-quadruplex binds to HIV-1 integrase (IN) and inhibits its activity during 3'-end processing at nanomolar concentrations. Herein we report a study concerning six T30695-GQ variants, in which the R or S chiral glycerol T, singly replaced the thymine residues at the T30695 G-quadruplex loops.

Plastic-associated harmful microalgal assemblages in marine environment.

Plastic debris carry fouling a variety of class-size organisms, among them harmful microorganisms that potentially play a role in the dispersal of allochthonous species and toxic compounds with ecological impacts on the marine environment and human health. We analyzed samples of marine plastics floating at the sea surface using a molecular qPCR assay to quantify the attached microalgal taxa, in particular, harmful species. Diatoms were the most abundant group of plastic colonizers with maximum abundance of 8.

Variability in Toxin Profiles of the Mediterranean Ostreopsis cf. ovata and in Structural Features of the Produced Ovatoxins.

Fifty-five strains of Ostreopsis were collected in the Mediterranean Sea and analyzed to characterize their toxin profiles. All the strains were grown in culture under the same experimental conditions and identified by molecular PCR assay based on the ITS-5.8S rDNA.

Toxin Variability Estimations of 68 Alexandrium ostenfeldii (Dinophyceae) Strains from The Netherlands Reveal a Novel Abundant Gymnodimine.

is a toxic dinoflagellate that has recently bloomed in Ouwerkerkse Kreek, The Netherlands, and which is able to cause a serious threat to shellfish consumers and aquacultures. We used a large set of 68 strains to the aim of fully characterizing the toxin profiles of the Dutch in consideration of recent reports of novel toxins. is known as a causative species of paralytic shellfish poisoning, and consistently in the Dutch population we determined the presence of several paralytic shellfish toxins (PST) including saxitoxin (STX), GTX2/3 (gonyautoxins), B1 and C1/C2.

Effects of N and P availability on carbon allocation in the toxic dinoflagellate Ostreopsis cf. ovata.

Blooms of the toxic dinoflagellate Ostreopsis cf. ovata are usually associated with shallow and calm coastal waters, characterized by low nutrient concentrations. The algal cells typically cover the benthic substrates, such as the macroalgal and invertebrate communities and rocks, forming a mucilaginous film.

Mediterranean Azadinium dexteroporum (Dinophyceae) produces six novel azaspiracids and azaspiracid-35: a structural study by a multi-platform mass spectrometry approach.

Azadinium dexteroporum is the first species of the genus described from the Mediterranean Sea and it produces different azaspiracids (AZA). The aims of this work were to characterize the toxin profile of the species and gain structural information on azaspiracids produced by the A. dexteroporum strain SZN-B848 isolated from the Gulf of Naples.

Ostreopsis fattorussoi sp. nov. (Dinophyceae), a new benthic toxic Ostreopsis species from the eastern Mediterranean Sea.

The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data.

An aquarium hobbyist poisoning: Identification of new palytoxins in Palythoa cf. toxica and complete detoxification of the aquarium water by activated carbon.

Palytoxin (PLTX) is a lethal natural toxin often found in Palythoa zoantharians that, together with its congeners, may induce adverse effects in humans after inhalation of toxic aerosols both in open-air and domestic environments, namely in the vicinity of public and private aquaria. In this study, we describe a poisoning of an aquarium hobbyist who was hospitalized after handling a PLTXs-containing zoantharian hexacoral. Furthermore, we provide evidence for water detoxification.

Ostreopsis cf. ovata from western Mediterranean Sea: Physiological responses under different temperature and salinity conditions.

The dinoflagellate Ostreopsis cf. ovata proliferates seasonally in the Mediterranean Sea, producing palytoxin-like compounds (ovatoxins) which are considered among the most potent marine toxins. Blooms have been related to several toxic events in which respiratory problems in humans and mortality of benthic marine organisms have been observed.

Ovatoxin-a, A Palytoxin Analogue Isolated from Ostreopsis cf. ovata Fukuyo: Cytotoxic Activity and ELISA Detection.

This study provides the first evaluation of the cytotoxic effects of the recently identified palytoxin (PLTX) analog, ovatoxin-a (OVTX-a), the major toxin produced by Ostreopsis cf. ovata in the Mediterranean Sea. Its increasing detection during Ostreopsis blooms and in seafood highlights the need to characterize its toxic effects and to set up appropriate detection methods.

Determination of Palytoxins in Soft Coral and Seawater from a Home Aquarium. Comparison between Palythoa- and Ostreopsis-Related Inhalatory Poisonings.

Anecdotal reports exist of aquarium hobbyists that experienced severe respiratory distress and/or skin injury following cleaning operation of home aquaria containing Palythoa sp. soft corals. Hundreds of cases of respiratory illness and/or dermatitis have been recorded in proximity to the sea concomitantly with algal blooms of Ostreopsis spp.