Antitumor and antioxidant activities of polysaccharides from the seaweed Durvillaea antarctica.

The present study was carried out to determine the antitumor and antioxidant activities of the seaweed Durvillaea antarctica. Extraction and purification of polysaccharides from D. antarctica were performed.

First Report of Domoic Acid Production from in Paracas Bay (Peru).

The Peruvian sea is one of the most productive ecosystems in the world. Phytoplankton production provides food for fish, mammals, mollusks and birds. This trophic network is affected by the presence of toxic phytoplankton species.

Rapid Domoic Acid Depuration in the Scallop and Its Transfer from the Digestive Gland to Other Organs.

Domoic acid (DA), the main toxin responsible for Amnesic Shellfish Poisoning, frequently affects the marine resources of Chile and other countries across the South Pacific, thus becoming a risk for human health. One of the affected resources is the scallop . Even though this species has a high commercial importance in Northern Chile and Peru, the characteristics of its DA depuration are not known.

Paralytic Shellfish Toxins in Surf Clams during a Large Bloom of Dinoflagellates Associated to an Intense Shellfish Mass Mortality.

In late February 2016, a harmful algal bloom (HAB) of was detected in southern Chiloé, leading to the banning of shellfish harvesting in an extended geographical area (~500 km). On April 24, 2016, this bloom produced a massive beaching (an accumulation on the beach surface of dead or impaired organisms which were drifted ashore) of surf clams in Cucao Bay, Chiloé. To determine the effect of paralytic shellfish poisoning (PSP) toxins in , samples were taken from Cucao during the third massive beaching detected on May 3, 2016.

Accumulation and Biotransformation of Toxins by the Surf Clam .

Surf clams, , were shown to accumulate toxins from blooms. Only pectenotoxin 2 (PTX2) and some of its derivatives were found, and no toxins from the okadaic acid group were detected. PTX2 seems to be transformed to PTX2 seco-acid (PTX2sa), which was found in concentrations more than ten-fold those of PTX2.

Gonyaulax taylorii, a new yessotoxins-producer dinoflagellate species from Chilean waters.

In summer 2009, during a survey in Bahía Mejillones, a dense bloom of a dinoflagellate from the genus Gonyaulax was detected, as well as the presence of yessotoxin. Phytoplankton samples were analyzed in detail by light and scanning electron microscopy (SEM), revealing the presence of Gonyaulax taylorii. Morphological examination showed that the cells in the bloom fit in Gonyaulax jollifei Murray et Whitting sensu Dodge, subsequently classified as Gonyaulax taylorii by Carbonell-Moore.

Depuration and anatomical distribution of domoic acid in the surf clam Mesodesma donacium.

In northern Chile, domoic acid (DA) has been detected in several bivalve species. In Mesodesma donacium, one of the most important commercial species for local fishermen, no information is available on depuration, or on the anatomical distribution of this toxin and its potential use as a palliative measure to minimize the consequences of ASP outbreaks. Deputation of DA is very fast in M.

First identification of azaspiracid and spirolides in Mesodesma donacium and Mulinia edulis from Northern Chile.

In an attempt to evaluate the risk for human consumption associated to the accumulation of lipophilic toxins by two commercially important bivalves: macha (Mesodesma donacium) and clam (Mulinia edulis) in Coquimbo Bay (Chile), monitoring of these species was carried out from March to September 2008. The samples were analyzed by liquid chromatography-mass spectrometry (LC-MS) to detect okadaic acid, dinophysistoxins, pectenotoxins, azaspiracids, yessotoxins and spirolides. Low levels of Azaspiracid-1 and 13-desmethyl C spirolide were found in both species.

The occurrence of domoic acid linked to a toxic diatom bloom in a new potential vector: the tunicate Pyura chilensis (piure).

The tunicate Pyura chilensis (Molina, 1782); Phylum Chordata; Subphylum Urochordata; Class Ascidiacea, common local name "piure" or sea squirt; a filter-feeder (plankton and suspended particles) sessile species; may play an important role in monitoring domoic acid (DA) the principal toxic component of Amnesic Shellfish Poisoning (ASP). Significant DA concentrations have been determined in tunicate samples, collected during a recent ASP outbreak in Bahía Inglesa, an important scallop (Argopecten purpuratus) farming area. Several infaunal species were tested for the presence of DA, in addition to the usual scallop monitoring programme.

Identification of pectenotoxins in plankton, filter feeders, and isolated cells of a Dinophysis acuminata with an atypical toxin profile, from Chile.

A bloom of Dinophysis acuminata produced, in autumn of 2005, a closure of the scallop harvesting in Bahía Inglesa, in the Chilean III region. Isolated cells of this Dinophysis species were shown to contain 180 pg cell(-1) of pectenotoxin 2 but neither okadaic acid nor any of its analogs or derivatives (at least at a detectable level). Examination of plankton and filter-feeder samples covering an area of ca.