Invertebrates that live in marine ecosystems, including corals, worms, and molluscs, appear to be endowed with the ability to make omega-3 fatty acids.
“Our study offers a significant paradigm shift,” said lead study author Dr. Oscar Monroig, Lecturer at the University of Sterling’s Department of Aquaculture.
“It shows that corals, rotifers, mollusks, polychaetes and crustaceans have enzymes called ‘desaturases’ that enable them to produce omega-3s.”
Dr. Monroig’s research takes a number of angles, namely the transfer of genes to invertebrates to produce omega-3 oils and the production of omega-3-rich biomass that can be used, for example, as fishmeal in crustacean fish farming, Molluscs, aquatic plants, algae and other organisms.
“Under certain culture conditions, these organisms can have improved biosynthetic abilities to enable or increase the production of omega-3s,” said Dr. Monroig.
“The biomass produced is a substitute for a high quality fish meal and contains lipids that are rich in omega-3 oils if the process was successful and the activation of the pathways was carried out successfully.
The discovery challenges the generally accepted principle that marine microbes such as microalgae and bacteria are responsible for virtually all of the primary production of omega-3s.
Research gains additional momentum as the omega-3 sector looks for new sources of omega-3 sources outside of krill and fish to respond to consumer demand and greater concern for sustainability.
“We believe that growing certain invertebrates under certain conditions so that we can turn what is a waste material into a nutritious biomass will help ease the pressure on omega-3 sources such as krill,” added Dr. Monroig added.
Dr. Monroig added that all interest has been based on the health benefits of an omega-3 oil supplement, which is regularly prescribed for common cardiovascular and inflammatory diseases in humans.
Study details .
Together with colleagues from the Universities of St. Andrews and Porto and the Spanish National Research Council, Dr. Monroig reported the existence of key enzymes such as methyl-end desaturases in a small number of invertebrates.
These enzymes, previously found in photosynthetic marine microalgae and bacteria, produced 121 methyl-end-desaturase sequences from 80 species.
As Dr. David Ferrier of the University of St. Andrews’ Scottish Oceans Institute explains that the horizontal gene transfer process may explain their unusually widespread use.
“It was very surprising to us to see how widespread these genes were, especially in animals that are so common and abundant in the ocean,” he said.
“It’s also fascinating that these genes seem to jump into an insect and a springtail through a process of horizontal gene transfer between very different organisms such as plants or fungi. .
“This was a controversial idea that genes can move this way, but our data seems pretty convincing that these genes did so in at least some of these species.”
The new research is likely to have an impact not only on the scientific community, but also on the general public and various industries involved in the manufacture of nutritional supplements.
“Invertebrate oils are different from fish oils,” said Dr. Monroig, who also revealed that he was in contact with a Norwegian company regarding the production of omega-3 rich oilfish meal.
“Depending on the species, they are generally richer in EPA and poorer in DHA. This is a characteristic of the invertebrate fatty acid profile compared to fish oil.
“The quality of the omega-3 oil is good. We also believe that the likelihood of heavy metal and bioxin pollutants building up in the oils produced by invertebrates will be minimal. “
Omega-3 models need a major overhaul..
The study concluded that models for estimating world production of long-chain omega-3 PUFA, largely engineered on the assumption that single-cell microorganisms are the only primary producers, “need major revision”.
“Long-chain omega-3 PUFA production by metazoa will no doubt be significant as the animals now known to have methylend-desaturases are abundant in global ecosystems,” the study added.
Dr. Gerard Bannenberg, Director of Compliance and Scientific Outreach of the Global Organization of EPA and DHA Omega-3s (GOED), said in the study: “We are expanding our understanding of the range of multicellular animals that desaturate polyunsaturated fatty acids at the omega-3 position can, considerably ”. .
“The nematode Caenorhabditis elegans omega-3 fatty acid desaturase fat-1 has long been known for it, and the transgenic mouse that expresses the fat-1 gene is an important animal model that was instrumental in demonstrating this role by endogenous long-chain polyunsaturated omega-3 fatty acids (LCPUFA) in the regulation of inflammatory and metabolic processes. .
“The study shows new natural sources of omega-3 fatty acids that go well beyond our previous understanding and suggests that new ways for the directed biosynthesis and sustainable production of eicosapentaenoic acid and docosahexaenoic acid (EPA and DHA) can be developed.”
Source: Advances in Science
Published online before printing: DOI: 10.1126 / sciadv.aar6849.
“Genes for de novo biosynthesis of polyunsaturated omega-3 fatty acids are widespread in animals.”
Authors: Naoki Kabeya, Miguel Fonseca, David Ferrier, Juan Navarro, Line Bay, David Francis, Douglas Tocher, L. Filipe C. Castro and Óscar Monroig.