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MACRO CASCADE – Cascading Marine Macroalgal Biorefinery

Periodic Reporting for period 3 - MACRO CASCADE (MACRO CASCADE – Cascading Marine Macroalgal Biorefinery)

Reporting period: 2019-10-01 to 2021-03-31

Macroalgae, or seaweed, is one of the largest un-exploited global biomass resources for a sustainable production of food and replacement of fossil resources. Open-sea-based cultivation of macroalgae in Europe has huge potential. However, large-scale cultivation will not be a reality unless we increase added value throughout the value chain with an integrated biorefinery concept. Macro Cascade has worked towards this vision by demonstrating large-scale cultivation and harvesting as well as developing a biorefinery technology platform to convert macroalgae to a variety of value-added products for different industry sectors. The project offers economic, environmental and social benefits using seaweed as raw material, with the aim to expand the employment in the maritime sector. Shipbuilders will have the opportunity to expand their markets by building innovative harvesting ships. Storage and conversion will provide high quality jobs at the plants. Biorefinery of the produced seaweed will create a portfolio of new ingredients for food, feed, cosmetics, and bioplastics. Furthermore, by minimizing the pressure on land resources, society as a whole will benefit from this project.
Macro Cascade has achieved its aim with main achievement as listed as below.
In WP1, the selective breeding with Saccharina latissima (sugar kelp) resulted in a hybrid having 28% higher yield than the most productive wildtype line (2.88 kg vs. 2.25 kg ww). The scalable cultivation of kelps has been shown with 100 km grow lines deployed at sea and an annual production capacity of 250-300 tons ww. A mechanical harvesting machine was tested, and the overall cost of cultivation was reduced by at least 75% during the project period. Commercial seeding of Palmaria palmata (dulse) was taken further with new screening methods and cleaning trials that provided new pieces necessary to complete the puzzle that is to cultivate P. palmata.
In WP2, different conditioning technologies e.g. screw-pressing, drying, and ensiling were investigated with protocols established. Long term storage by ensiling showed promising and different conditions should be chosen depending on the targeted bioactive compounds in the following biorefinery process.
In WP3, Systematic assessments of novel microbes showing probiotic potential, discovery and characterization of new enzymes acting on macroalgae were carried out. Feed and food grade products using controlled lactic acid bacterial fermentation of seaweed and canola were developed. Feed grade product was tested in weaned piglets for a period of 9 weeks at two inclusion levels (2.5 % and 5 %, dry feed basis). A systemic improvement in the piglets was observed, from a positive gut microbial modulation to improvement in gut development and reduction in inflammation. A clinical trial on humans was carried out testing fermented seaweed-canola as prebiotic vs. a placebo in 49 patients having chronic inflammatory disease in their intestines and joints. Approximately 1/3 of the patients reported positive effect of the algae-canola fermented prebiotic, when asked in the clinic by the physicians investigators. This could be seen as small (3%) but not statistical significant on the inflammatory marker Faeces calprotectin, but no change in the intestinal microbiome was observed.
In WP4, protocols for extraction/separation of laminarin, alginate, fucoidan, mannitol and proteins were developed, supported by experimental data and model data for industrial scale operation. Compiling all knowledge gathered in this WP, a final biorefinery scheme was constructed with the most likely biorefinery process for S. latissima.
In WP5, several enzymes were produced and procedures were designed and tested for refining the algal polysaccharides (laminarin, fucoidan, alginate) with potential uses of the products in food, feed, cosmetic and chemical industries. Some promising processes were optimized and scaled up, including the processes for producing branched beta glucan oligosaccharides from laminarin, and enzymatic processes for producing valuable building blocks from alginate. A full patent were obtained for the former in selected European countries and a PCT patent has been filed for the latter. Chemical processes were also developed for generation of chemicals of industrial interest from the enzymatically produced alginate intermediates. Highly novel fucoidanases were discovered and developed, which can be used for generating innovative bioactive derivatives of fucoidan.
In WP6, the technical and economic prospects for seaweed cultivation, storage and valorisation towards high-value products was evaluated. Process design and performance, capital cost and operating costs were significant in all steps. The primary cost driver found is the cost of seaweed cultivation. The best economics are for functional food, followed by functional feed. A multiproduct cascading scheme and production of pre-biotics have a good potential but require further optimization and development. A life cycle assessment found that the environmental impact is mainly in the energy use for seaweed drying when this is applied. The social and regional impact of seaweed cultivation and valorisation was assessed. Finally, a sustainable business case for a “Blueprint” of the cascading marine macroalgal biorefinery was developed.
•A Macro Cascade demonstrated offshore cultivation system is so far proven to be scalable, survivable in open ocean conditions, and the content of seaweed can be predicted. The impact of these achievements has been a concrete technology transfer of the off-shore MACR system used in Macro Cascade (including direct seeding techniques).
•A comprehensive and unique selective breeding program of different S. latissima strains was made. When the project initiated there was no prior attempt in Europe to breed, cultivate and process macroalgae for targeted higher value biomolecules according to industrial requirements. Validation of 1 high performing strain based on the selective breeding was found.
•The overall cost is a function of yield compared to total capital and operating cost (CAPEX+OPEX / Yield) provided data on actual costs of a production scale of up to 100 tons wet weight of cultivated seaweed per year. The overall cost has been reduced significantly, but the capital cost and cost of operation are still significant in the economic feasibility study. It is further lowered due to mechanization, selective breeding and economy of scale.
•Several promising processes of refining algal polysaccharides to the products in food, feed, cosmetic and chemical industries are optimized and scaled up. A full patent was obtained and a PCT patent has been filed for the latter.
•Feed and food ingredients of controlled lactic acid bacterial fermented canola and seaweed were developed and tested. Anti-inflammatory activities in human cells were documented and the optimized food grade product had a positive effect (33%) in patients with Inflammatory Bowel Disease at Silkeborg Hospital in Denmark. Feed grade products were tested in pigs to (out-phase zinc or antibiotics) for reducing diarrhea and with promising results. Thus, Macro Cascade has potential impact on both human and animal health by providing healthy seaweed-based feed and food ingredients with pre- and probiotic functionalities.
Activities of seaweed cultivation in the Faroe Islands