Simultaneous Extraction and Depolymerization of Fucoidan from Sargassum muticum in Aqueous Media

Abstract

The biomass components of the invasive seaweed Sargassum muticum were fractionated to allow their separate valorization. S. muticum (Sm) and the solid residue remaining after alginate extraction of this seaweed (AESm) were processed with hot, compressed water (hydrothermal processing) to assess the effects of temperature on fucoidan solubilization. Fucose-containing oligosaccharides were identified as reaction products. Operating under optimal conditions (170 °C), up to 62 and 85 wt% of the dry mass of Sm and AESm were solubilized, respectively. The reaction media were subjected to precipitation, nanofiltration and freeze-drying. The dried products contained 50% and 85% of the fucoidan present in Sm and AESm, respectively; together with other components such as phenolics and inorganic components. The saccharidic fraction, accounting for up to 35% of the dried extracts, contained fucose as the main sugar, and also galactose, xylose, glucose and mannose. The concentrates were characterized for antioxidant activity using the TEAC assay.

High-value products from macroalgae: the potential uses of the invasive brown seaweed, Sargassum muticum

“…S. muticum contains 8 % dry weight as fucans (Gorham and Lewey 1984) with fucose being the dominant sugar in S. muticum sulphated polysaccharides (Balboa et al 2013). S. muticum harvested in Kent was found to have a lower sulphur content (1.5 % dw) than A. nodosum (2.51 % dw) (Milledge 2014 unpublished data).…”

Suitability of hydrothermal liquefaction as a conversion route to produce biofuels from macroalgae

“…In this sense, the work described by González-López et al [33] or Balboa et al [8] proposing a mild hydrothermal fractionation of seaweeds to obtain fucoidan, alginate and other high-value products from carbohydrates is interesting. The carbohydrate fraction from seaweeds can be used as well to produce bioethanol by fermentation or to obtain other valuable products: mannitol can be converted to isomannide; laminarin can be fermented to acetone, butanol or ethanol; and alginate can be converted to furan dicarboxylic acid [4].…”

“…They can be used to produce alginates, fodder, chemicals, health or body care products [2,8]. All these products have market values higher than biofuels, but their recovery leaves behind waste biomass that needs to be processed to minimize the production of residues.…”

Golden Tides: Problem or Golden Opportunity? The Valorisation of Sargassum from Beach Inundations

“…S. muticum contains 8% dry weight as fucans [68], with fucose being the dominant sugar in S. muticum sulphated polysaccharides [69]. Fucans have been classified as non-toxic.…”