Nutritional Composition of Beach-Cast Marine Algae from the Brazilian Coast: Added Value for Algal Biomass Considered as Waste

Abstract

In some coastal areas, large quantities of beach-cast macroalgae can accumulate and are usually considered waste and disposed of. However, due to their biofunctional and nutritional properties, they have great potential as a new source of raw materials. Increasing population growth has made the search for alternative raw materials with valuable nutritional properties urgent; here, beach-cast macroalgae could provide great potential. Our research goal was to characterize the nutritional profile of 12 beach-cast seaweed species from the Brazilian coast to assess their potential valorization. A considerable number of nutritional compounds was observed, such as ash (6.5–59.3%), total dietary fibers (22.1–65.8%), proteins (5.1–21.5%), and carbohydrates (31.4–81.0%), with an expressive abundance of minerals, free amino acids, and fatty acids. Spatoglossum schroederi and Alsidium seaforthii showed protein contents of 21.5 ± 0.2%, 19.7 ± 0.1%, and high amounts of total dietary fiber of 59.2 ± 0.4%, 61.7 ± 4.9%, respectively. The overall profile suggests that beach-cast seaweeds are suitable for nutritional and other bioeconomical purposes, to which different species with different characteristics contribute. Contamination of these seaweeds with unwanted toxic compounds like micropollutants was not studied. However, this must be considered before they are used for human consumption.

Seaweeds and Corals from the Brazilian Coast: Review on Biotechnological Potential and Environmental Aspects

“…Seaweeds from Brazil are a potential source of microelements and other compounds that have beneficial effects [206]. However, new analytical approaches are needed to describe their amounts.…”

Biotechnological Potential of Macroalgae during Seasonal Blooms for Sustainable Production of UV-Absorbing Compounds

“…were found to be significantly impacted by extraction solvent used, with the highest yield (increased up to 32.34%) obtained when 25% of ethanol was used compared to other extraction solvents [139]. In addition, there are still significant challenges in harvesting bloom biomass from beach cast areas as well as the water, rapidly separating species of interest from harvested blooms, purifying algal tissues for the extraction of compounds of interest, and conducting all steps with an economically viable approach [57,147,148].…”

Enzyme-Assisted Extraction of Ulvan from the Green Macroalgae Ulva fenestrata

“…Total protein, amino acids distribution, and lipid and ash content were determined from Ulva fenestrata biomass, as described below. The total carbohydrate content was calculated considering that protein, lipid, ash, and carbohydrates are the main macroalgae biomass components and account for 100% dw [42]. For all analysis, samples were placed in a −20 • C freezer overnight and then lyophilized on an Alpha 1-2 LD plus freeze dryer (Martin Christ Gefriertrocknungsanlagen GmbH, Germany) in a two-step procedure including main drying and final drying in a laboratory.…”