Marine macroalgae have emerged as a promising source of natural metabolites with remarkable health benefits. Researchers from Tel-Aviv University and Israel Oceanographic & Limnological Research Ltd. have embarked on a study, published in Marine Drugs, to unlock the potential of seaweeds in enhancing the production of antioxidant and photoprotective biomaterials. Their innovative approach involves optimising seaweed cultivation techniques through an integrated multi-trophic aquaculture (IMTA) system. This article delves into the study’s findings, shedding light on the practical implications for the seaweed industry and the untapped potential of sustainable and functional biomass.
Expanding the boundaries of seaweed cultivation
While microalgae have dominated research in recent years, seaweeds offer distinct advantages, including high yield, robust growth, bioremediation capabilities, and a rich chemical profile. With nearly 3000 different natural products, seaweeds represent a significant portion of the marine realm’s chemical diversity. Compared to the less economically viable production of microalgae, seaweed cultivation holds immense promise for mass-scale sustainable biomass cultivation.
Unveiling seaweed’s chemical defence mechanisms
Intertidal seaweed genera such as Ulva, Gracilaria, and Hypnea possess remarkable chemical defence mechanisms and the ability to enhance secondary metabolites. Mycosporine-like amino acids (MAAs), phenolic compounds, and pigments are among the valuable compounds that seaweeds can produce in response to changing environmental conditions. By artificially stimulating seaweed metabolism, the researchers sought to bolster the production of specific antioxidant and photoprotective biomaterials.
The two-phase cultivation approach
The researchers developed a practical two-phase cultivation plan within the IMTA system. Initially, three seaweed species were cultivated using fish effluents, capitalising on their mutualistic relationship. Subsequently, the seaweeds were exposed to various abiotic stresses, including high irradiance, nutrient starvation, and high salinity. This unique approach, inspired by microalgae cultivation techniques, represents a novel application in seaweed cultivation.
Empowering seaweeds for enhanced biomaterials
The study’s findings highlight the remarkable capacity of the IMTA system and abiotic stressors to elevate the content of beneficial compounds in seaweeds. By leveraging the integrated cultivation system, seaweeds exhibited a significant increase in MAAs, phenolic compounds, antioxidants, sun protection factor (SPF), as well as enhanced chlorophyll and phycobiliprotein synthesis. These results demonstrate the immense potential of seaweed biomass as a high-quality raw material for various applications.
Unlocking the future of seaweed cultivation
An earlier 2014 study published in the Journal of Applied Phycology analysed tests on seaweed extracts from different places and discovered that they have the potential to be strong anti-cancer drugs. It was found that different compounds like polysaccharides, polyphenols, proteins, carotenoids, alkaloids, and terpenes found in seaweeds showed capabilities in stopping key processes in cancer cells. Even though the study highlighted promise for cancer treatment, at the time, there were still no practical anti-cancer drugs from seaweeds available for use. The report aimed to help researchers who wanted to further investigate seaweed as a potential source for new anti-cancer drugs.
Just 8 years later, the scientific advancement of seaweed compound extraction and the implications of this new study shows the extent of seaweed benefits. By fine-tuning cultivation techniques, seaweeds can be manipulated to yield additional bioactive compounds such as antibiotics, antivirals, anti-inflammatories, and antidiabetic substances. This opens up exciting possibilities for the emerging seaweed industry, catering to diverse sectors including food, health, pharmaceuticals, cosmetics, and bio-refinery processes.
A sustainable advantage
The IMTA cultivation system not only promotes the growth and biosynthesis of seaweeds but also offers an ecological advantage. By assimilating inorganic nutrients from the water, seaweeds contribute to minimising the risk of coastal eutrophication, thus ensuring a sustainable approach to cultivation.
These studies signify a significant step towards unlocking the potential of seaweeds for enhanced biomaterial production, nutraceuticals and customised nutrition. Through their innovative two-phase cultivation approach within the IMTA system, the researchers have demonstrated how seaweeds can be harnessed to yield a wide array of valuable compounds. The findings provide practical insights for the seaweed industry, illuminating a sustainable path towards mass-scale cultivation of functional and high-value biomass. With continued research and exploration, the future of seaweed cultivation holds immense promise for revolutionising the food, health, and bio-based industries.
Ashkenazi, D.Y.; Figueroa, F.L.; Korbee, N.; García-Sánchez, M.; Vega, J.; Ben-Valid, S.; Paz, G.; Salomon, E.; Israel, Á.; Abelson, A. Enhancing Bioproducts in Seaweeds via Sustainable Aquaculture: Antioxidant and Sun-Protection Compounds. Mar. Drugs 2022, 20, 767. https://doi.org/10.3390/md20120767