The Use of the Marine Microalga Tisochrysis lutea (T-iso) in Standard Toxicity Tests; Comparative Sensitivity With Other Test Species

Abstract

The marine flagellate Tisochrysis lutea (T-iso), with a global distribution, is one of the most common microalgae used as natural food in aquaculture. In recent years Tiso has also been increasingly used in toxicity testing, although it is not included in current international protocols such as ISO that relies on Phaeodactylum tricornutum and Skeletonema costatum as marine species, and Raphidocelis subcapitata as freshwater species. Sensitivity of Isochrysis galbana to selected model toxicants was compared with that of those recommended species using the 72 h growth-rate inhibition response. Internationally accepted standard methods with fixed test conditions (light intensity, photoperiod, temperature, nutrients concentrations, initial cell density, time of exposure and endpoint) were followed to allow this comparison. Toxicity of model chemicals representative of the main environmental toxicants-a trace metal (zinc), a polyaromatic hydrocarbon (fluoranthene), an herbicide (benzalkonium chloride), an insecticide (chlorpyrifos), a surfactant (4-nonylphenol), and a microbiocide (triclosan)were evaluated to determine EC 50 and EC 10 values. In general, T-iso showed higher sensitivity for most groups of toxicants, meeting the acceptability criteria in terms of control growth set in standard protocols. For example, EC 50 and EC 10 of T-iso for chlorpyrifos were 246 µg L −1 and 132 µg L −1 , whereas for P. tricornutum these values were ca. fivefold higher: 1117 and 746 µg L −1 respectively. Therefore, the use of T-iso in marine toxicity testing as a standard model representative of photosynthetic organisms is recommended.

Updated pigment composition of Tisochrysis lutea and purification of fucoxanthin using centrifugal partition chromatography coupled to flash chromatography for the chemosensitization of melanoma cells

“…This species is widely used in aquaculture because it contains a high amount of polyunsaturated fatty acids (PUFAs), notably docosahexaenoic acid (DHA). T. lutea also presents a promising nutraceutical and pharmaceutical potential [2][3][4] because of its high content in carotenoids and vitamins [5,6]. Preliminary analyses of its pigment composition by our research group have shown high amounts of fucoxanthin and unidentified carotenoids (named Car43 and Car48) of chemotaxonomic interest [7].…”

Ecotoxicological Evaluation of Sunscreens on Marine Plankton

“…The algal growth inhibition test was carried out according to the standard method from [49] adapted to T. lutea by [50]. The initial strain of T. lutea was obtained from the ECIMAT-Universidade de Vigo collection.…”

Influence of zinc and iron on population dynamics, morphology and fluorescent properties of <i>Prorocentrum foraminosum</i> (Dinophyta)

“…Численность клеток -показатель, традиционно используемый для оценки действия веществ на микроводоросли [Panneerselvam et al, 2018;Tato and Beiras, 2019]. Хлоропласты -основная мишень действия токсических веществ у водорослей и высших растений, данный показатель изменяется при воздействии избытка тяжелых металлов и применяется для оценки физиологических нарушений у микроводорослей [Carfagna et al, 2013].…”