Determination of brevetoxin in recent marine sediments

Mendoza, Wilson G.; Mead, Ralph N.; Brand, Larry E.; Shea, Damian

doi:10.1016/j.chemosphere.2008.07.089

Cited by 28 publications

(18 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Concentrated fractions were measured for brevetoxins using an Agilent 1100 LC coupled to a Thermo-Finnigan TSQ Quantum triple quadrupole mass spectrometer with an electrospray ion source interface. LC-MS-MS conditions have been previously described in detail [48],[49]. An external standard curve of purified brevetoxins 1, 2, and 3 (World Ocean Solutions, Wilmington, NC, USA) was used to quantify amounts of extracted brevetoxins.…”

Section: Methodsmentioning

confidence: 99%

Increased Toxicity of Karenia brevis during Phosphate Limited Growth: Ecological and Evolutionary Implications

et al. 2013

Self Cite

View full text Add to dashboard Cite

Karenia brevis is the dominant toxic red tide algal species in the Gulf of Mexico. It produces potent neurotoxins (brevetoxins [PbTxs]), which negatively impact human and animal health, local economies, and ecosystem function. Field measurements have shown that cellular brevetoxin contents vary from 1–68 pg/cell but the source of this variability is uncertain. Increases in cellular toxicity caused by nutrient-limitation and inter-strain differences have been observed in many algal species. This study examined the effect of P-limitation of growth rate on cellular toxin concentrations in five Karenia brevis strains from different geographic locations. Phosphorous was selected because of evidence for regional P-limitation of algal growth in the Gulf of Mexico. Depending on the isolate, P-limited cells had 2.3- to 7.3-fold higher PbTx per cell than P-replete cells. The percent of cellular carbon associated with brevetoxins (%C-PbTx) was ∼ 0.7 to 2.1% in P-replete cells, but increased to 1.6–5% under P-limitation. Because PbTxs are potent anti-grazing compounds, this increased investment in PbTxs should enhance cellular survival during periods of nutrient-limited growth. The %C-PbTx was inversely related to the specific growth rate in both the nutrient-replete and P-limited cultures of all strains. This inverse relationship is consistent with an evolutionary tradeoff between carbon investment in PbTxs and other grazing defenses, and C investment in growth and reproduction. In aquatic environments where nutrient supply and grazing pressure often vary on different temporal and spatial scales, this tradeoff would be selectively advantageous as it would result in increased net population growth rates. The variation in PbTx/cell values observed in this study can account for the range of values observed in the field, including the highest values, which are not observed under N-limitation. These results suggest P-limitation is an important factor regulating cellular toxicity and adverse impacts during at least some K. brevis blooms.

show abstract

Section: Methodsmentioning

confidence: 99%

Increased Toxicity of Karenia brevis during Phosphate Limited Growth: Ecological and Evolutionary Implications

et al. 2013

Self Cite

View full text Add to dashboard Cite

show abstract

“…Brevetoxin can be found in the sediments (Mendoza et al, 2008). Sublethal concentrations however, do not kill animals initially, allowing brevetoxin to accumulate in tissues and then propagate up the food chain, until high enough concentrations build up in the tissues of top carnivores that they become lethal.…”

Section: Ecosystem Pathways For Toxinsmentioning

confidence: 98%

Karenia: The biology and ecology of a toxic genus

2012

Self Cite

View full text Add to dashboard Cite

“…Concentrated fractions were measured for brevetoxins using an Agilent 1100 liquid chromatograph coupled to a Thermo-Finnigan TSQ Quantum triple quadrupole mass spectrometer with an electrospray ion source interface. The analytical conditions have been previously described in detail (46,47). An external standard curve of purified brevetoxins 1, 2, and 3 (World Ocean Solutions) was used to quantify amounts of extracted brevetoxins.…”

Section: Methodsmentioning

confidence: 99%

Osmotic stress does not trigger brevetoxin production in the dinoflagellateKarenia brevis

Sunda

Burleson

Hardison

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

With the global proliferation of toxic harmful algal bloom species, there is a need to identify the environmental and biological factors that regulate toxin production. One such species, Karenia brevis, forms nearly annual blooms that threaten coastal regions throughout the Gulf of Mexico. This dinoflagellate produces brevetoxins, which are potent neurotoxins that cause neurotoxic shellfish poisoning and respiratory illness in humans, as well as massive fish kills. A recent publication reported that a rapid decrease in salinity increased cellular toxin quotas in K. brevis and hypothesized that brevetoxins serve a role in osmoregulation. This finding implied that salinity shifts could significantly alter the toxic effects of blooms. We repeated the original experiments separately in three different laboratories and found no evidence for increased brevetoxin production in response to low-salinity stress in any of the eight K. brevis strains we tested, including three used in the original study. Thus, we find no support for an osmoregulatory function of brevetoxins. The original publication also stated that there was no known cellular function for brevetoxins. However, there is increasing evidence that brevetoxins promote survival of the dinoflagellates by deterring grazing by zooplankton. Whether they have other as-yet-unidentified cellular functions is currently unknown. red tides | toxic blooms | HABs H armful algal blooms threaten human health and damage coastal ecosystems worldwide. In the Gulf of Mexico, the athecate dinoflagellate Karenia brevis causes nearly annual toxic blooms. The physiology, ecology, and adverse effects of K. brevis have been well studied since the species was described in the 1940s (1). Notably, K. brevis produces brevetoxins, a family of potent polyether neurotoxins that bind to voltage-activated sodium channels in cell membranes, preventing normal nerve and muscle activity (2, 3). A nontoxic polyether that inhibits brevetoxin function, brevenal, is also produced in small amounts by this species (4). In humans, brevetoxins cause neurotoxic shellfish poisoning, and brevetoxin-contaminated aerosols cause respiratory irritation and illness (2, 5). Blooms also cause massive fish kills (6), as well as bird and marine mammal mortalities (7,8). In 2005, a bloom of K. brevis lasted for more than a year and caused extensive mortalities at all trophic levels in lagoons, coastal ecosystems, and offshore reefs on the west Florida shelf (8, 9).Because of the extensive damage caused by K. brevis, there has been considerable interest in understanding the function and regulation of brevetoxins. Competition experiments reveal that K. brevis produces allelopathic compounds, which inhibit the growth of competing phytoplankton and thereby help enable this slowgrowing species to dominate; however, brevetoxins themselves do not appear to be responsible for this inhibition (10, 11). Recent studies support the hypothesis that brevetoxins serve as grazing deterrents, which promote population survival by decrea...

show abstract

Determination of brevetoxin in recent marine sediments

Cited by 28 publications

References 29 publications

Increased Toxicity of Karenia brevis during Phosphate Limited Growth: Ecological and Evolutionary Implications

Increased Toxicity of Karenia brevis during Phosphate Limited Growth: Ecological and Evolutionary Implications

Karenia: The biology and ecology of a toxic genus

Osmotic stress does not trigger brevetoxin production in the dinoflagellateKarenia brevis

Contact Info

Product

Resources

About