Chromatography Maps Omega-3s in Macroalgae

Over the past few decades, algae have become a major focus for transforming how we produce food, largely because they're a rich source of omega-3 fatty acids. But because macroalgae contain such a wide and complicated mix of fats, scientists have struggled to find good methods for fully mapping out all these different lipids and successfully separating out the omega-3s so they can be used as dietary supplements for people.

To tackle this challenge, researchers developed a large-scale, comprehensive approach to thoroughly map out the fats found in different types of marine macroalgae — both the kinds sold commercially, and the kinds considered invasive pests. They did this by combining chromatography techniques with mass spectrometry, as well as using methods that can analyze samples directly with little to no preparation beforehand. A paper based on their work was published in Analytica Chimica Acta.¹

Why Are Dietary Fats, Especially Omega-3 Fatty Acids, Important for Human Health?

Even though scientists have studied fats for a long time, it has only been in the last twenty years or so that lipids have become a major focus in fields like human health and nutrition. Since fats play a role in so many of the body's processes, they have a real impact on the health of individual cells and the body as a whole.² Because of this, researchers have increasingly looked at dietary fat intake as a promising way to prevent disease and support better treatment options.

Among these fats, polyunsaturated fatty acids (especially omega-3s like EPA and DHA) are widely considered some of the most important nutrients man needs to get from food, since eating more of them has been linked to a lower risk of heart disease and related deaths.³ There is also growing evidence that eating more of another omega-3, called ALA, may offer additional health benefits.⁴

What Analytical Methods Did the Researchers Use to Study Macroalgae Lipids, and What Did They Find?

For this research, the team used gas chromatography combined with mass spectrometry (GC-MS) and flame ionization detection (FID) to identify fatty acid ethyl esters, while reversed-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) allowed them to separate lipids by class and identify them in their natural, unmodified form. A particular focus was placed on shrinking down and fully automating the sample preparation steps using robotic systems directly linked to the chromatography instruments. Alongside this, the researchers also used a rapid evaporative ionization mass spectrometry system fitted with an electrosurgical knife as a quick, all-in-one technique to generate lipid "fingerprints" of the macroalgae. Finally, they used supercritical fluid chromatography (SFC) to isolate the fatty acid ethyl esters, with the goal of creating omega-3-enriched formulations.¹

Overall, brown macroalgae turned out to have the most complex mix of fats, followed by green and then red macroalgae. The researchers also created a visual comparison combining two sets of data to see how different types of fatty acids related to the intact lipid types found in the samples, helping them understand how these compounds connect to one another.¹

The research indicated that macroalgae seem to be a sustainable way to get omega-3 fatty acids, fitting in well with broader goals around building an eco-friendly ocean-based economy and a circular, bio-based economy. Importantly, this research helped highlight the value of marine macroalgae in the health and nutrition space, supporting their potential as an effective plant-based (non-animal) source of essential fatty acids.¹

Read More on Similar Topics
Investigating Microalgae Using GC and HPLC–MS

References

1. Rigano, F.;Donnarumma, D.; Vento, F. et al. Lipidomic Profiling of Mediterranean Macroalgae by Hyphenated Chromatography-Mass Spectrometry and Ambient Ionization Mass Spectrometry Techniques. Anal Chim Acta 2026, 1417, 345810. DOI: 10.1016/j.aca.2026.345810
2. Donnarumma, D.; Micalizzi, G.; Mondello, L. et al. Lipidomics in Food Industry and Nutrition in Mass Spectrometry for Lipidomics: Methods and ApplicationsHolčapek, M.; Ekroos, K. Eds (1^st ed.). Wiley, 2023. pp. 585-600, 10.1002/9783527836512.ch21
3. Zhang, Y.; P. Zhuang, P.; W. He, W. et al. Association of Fish and Long‐Chain Omega‐3 Fatty Acids Intakes with Total and Cause‐Specific Mortality: Prospective Analysis of 421 309 Individuals.J. Intern. Med.2018, 284, 399-417. DOI: 10.1111/joim.12786
4. Sala-Vila, A.; Fleming, J.; Kris-Etherton, P.et al. Impact of α-Linolenic Acid, the Vegetable ω-3 Fatty Acid, on Cardiovascular Disease and Cognition. Adv. Nutr.2022, 13, 1584-1602. DOI: 10.1093/advances/nmac016