Climate change could lead to a severe temperature-related drop in essential Omega-3 fatty acids, according to a new study – Rising because of that?
[ok, ok, I think this one might win an award for speculative fiction-cr]
IMAGE: MIT-WHOI JOINT VENTURE PROGRAM STUDENTS HENRY HOLM PUMPING SEA WATER FOR LIPID SAMPLES FROM THE SEA BENEATH ICE ON WESTERN WATERPROOF PENINSULA, 2018. THIS IS FOR A WORLDWIDE LED STUDY TYPES OF LIPIDS IN THE OCEAN IN SOME COMMANDS -3 FACIAL ACID. see more
CREDIT: IMAGE CREDIT: BENJAMIN VALVE MOOY / © WOODS HOLE OCEANOGRAPHIC INSTITUTION
WOODS HOLE OCEANOGRAPHIC INSTITUTION
The effects of global climate change have led to loss of sea ice, faster sea level rise and longer and more intense heat waves, among other threats.
Now, the first survey of plankton lipids in the global ocean predicts a temperature-related decrease in production of essential omega-3 fatty acids, an important subset of molecules. lipids.
An important implication of the survey is that as global warming progresses, there will be less and less plankton-produced omega-3 fatty acids at the bottom of the food web, which means there will be less omega-3 fatty acids for fish and for humans. . Omega-3 fatty acids are an essential fat that the human body cannot produce on its own and are considered by many to be the “good” fat that links seafood consumption with heart health.
According to a new paper led by authors from the Forest Hole Oceanographic Institute (WHOI).
“Focusing on ten molecularly diverse classes of glycerolipid, we identified 1,151 distinct lipid classes, finding that fatty acid unsaturation (i.e. number of carbon-to-carbon double bonds) is essentially limited by temperature. We predicted a significant decrease in the essential fatty acid eicosapentaenoic acid [EPA] over the next century, likely to have severe adverse effects on economically important fisheries,” the paper says, “Global ocean lipids reveal a universal relationship between temperature and lipid unsaturation”, published in Science.
EPA is one of the most nutritious omega-3 fatty acids, has been linked to many health benefits, and is widely sold as a dietary supplement.
“The lipids in the ocean affect your life,” said co-author of the journal article Benjamin Van Mooy, senior scientist in WHOI’s Department of Marine Geochemistry and Chemistry. “We found that the lipid composition in the ocean changes as the ocean warms. That is a cause for concern. We need the fats found in the oceans because they affect the quality of the food the oceans produce for humanity. “
“All organisms in the ocean have to deal with water temperatures. With this study, we’ve revealed one of the key biochemical ways cells do it,” said lead author of the journal paper Henry C. Holm, a doctoral student at the Institute of Technology. Massachusetts (MIT) – WHOI Joint Program on Applied Oceanography/Oceanics said. Science and engineering. “These EPA findings were made using a method that gives us a very complete picture of the gylcerolipids in each sample. We found that temperature was linked with saturation of cell membranes everywhere we looked in the ocean.”
Lipids are a class of biomolecules produced and used by organisms from all walks of life for energy storage, membrane structure, and signaling. They make up about 10-20% of the plankton at the ocean’s surface, where the largest lipid producer and stockpile is located. Oceanographers have used lipids as biomarkers of chemical and biological processes for decades, and there has been intense research on their biochemistry. However, only recently has the combination of high-resolution mass spectrometry and downstream analytical tools enabled a comprehensive, untargeted assessment of ocean lipids on a scale similar to surveys of marine lipids. other molecules such as nucleic acids and proteins.
In this new survey, the researchers examined a global mass spectroscopic dataset of plankton lipidomes from 146 sites collected during seven oceanographic research voyages between 2013 and 2018. . The researchers note that although plankton biome lipids are influenced by many environmental factors such as nutrient availability, the paper reports on “the relationship between lipids and control most fundamental to their composition: temperature”.
The researchers examined the saturation states of 10 major lipids with glycerol (i.e. glycerolipid) and found that among those classes, “temperature has a major influence on structuring relative abundances.” of fatty acids”. In addition, the researchers discovered a clear transition from lipids with more unsaturated fatty acids at colder temperatures to fully saturated ones at the warmest temperatures.
“These trends were also evident in all other glycerolipid classes as well as the total lipid synthesis of all glycerolipid classes,” the paper reads. “Indeed, it is surprising that the relationship between temperature and unsaturation appears in our data set despite spanning such diverse and distinct plankton communities, from nutrient-depleted subtropical soils to the highly productive Antarctic coastal shelf”.
The researchers also found that the percentage abundance of eicosapentaenoic acid (EPA) species showed a strong relationship with temperature. To determine how the upper and lower bounds of the EPA composition might change under future warming conditions, the researchers created a map using sea surface temperature conditions at the end of the year. century for different climate scenarios.
Under the SSP5-85 climate scenario, which the paper notes is considered a worst-case scenario with persistently high levels of greenhouse gas emissions, some oceanic regions — particularly at higher latitudes — experience levels of as much as -25% off the EPA from what they have now, according to the article.
Van Mooy said the study “is another example of how human activities are stirring up the oceans in ways we never expected, and of the uncertainty about how the oceans will react.” response to warming”.
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