Designed optimization of a single-step extraction of fucose-containing sulfated polysaccharides from Sargassum sp.

Abstract

Fucose-containing sulfated polysaccharides can be extracted from the brown seaweed, Sargassum sp. It has been reported that fucose-rich sulfated polysaccharides from brown seaweeds exert different beneficial biological activities including anti-inflammatory, anticoagulant, and anti-viral effects. Classical extraction of fucose-containing sulfated polysaccharides from brown seaweed species typically involves extended, multiple-step, hot acid, or CaCl 2 treatments, each step lasting several hours. In this work, we systematically examined the influence of acid concentration (HCl), time, and temperature on the yield of fucosecontaining sulfated polysaccharides (FCSPs) in statistically designed two-step and single-step multifactorial extraction experiments. All extraction factors had significant effects on the fucose-containing sulfated polysaccharides yield, with the temperature and time exerting positive effects, and the acid concentration having a negative effect. The model defined an optimized single-step FCSPs extraction procedure for Sargassum sp. (a brown seaweed). A maximal fucosecontaining sulfated polysaccharides yield of ∼7% of the Sargassum sp. dry matter was achieved by the optimal extraction procedure of: 0.03 M HCl, 90°C, 4 h. HPAEC-PAD analysis confirmed that fucose, galactose, and glucuronic acid were the major constituents of the polysaccharides obtained by the optimized method. Lower polysaccharide yield, but relatively higher fucose content was obtained with shorter extraction time. The data also revealed that classical multi-step extraction with acid ≥0.2 M HCl at elevated temperature and extended time had a detrimental effect on the FCSPs yield as this treatment apparently disrupted the structural integrity of the polymer and evidently caused degradation of the carbohydrate chains built up of fucose residues.

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

“…The solubilization yields decreased with temperatures in the range tested, a fact ascribed to the instability of fucose-containing compounds under harsh conditions [6]. …”

“…Due to their non-toxic character, fucoidans have been recently explored for medicinal properties, but their detailed structural analysis is complex [11], and the structure–activity interrelationships are not yet clear [6,12]. …”

“…The extraction conditions have to be controlled carefully, as fucoidans are sensitive to degradation [6]. Since some methods cannot analyze large molecules, partial depolymerization of fucoidans has been carried out with acids [4] or radicals [12] before analysis.…”

Optimization of ultrasound assisted extraction of bioactive components from brown seaweed Ascophyllum nodosum using response surface methodology

“…However, acid concentration did not have a significant effect on fucose level. Ale, Mikkelsen and Meyer [26] reported that 0.03 M HCl was the optimal concentration for extraction of fucose containing sulphated polysaccharides from Sargassum sp.…”

Fucoidan, A Sulfated Polysaccharides from Brown Algae as Therapeutic Target for Cancer

“…In addition to sulfate these backbone residues may be substituted with fucosides, single fucose substitutions, and/or glucuronic acid, xylose or glucose substitutions [21]. The compositional and structural features of FCSPs differ significantly among seaweed species and that these features are markedly influenced by the conditions used to extract them [20,23]. Fucoidan extracted from brown seaweed algae Fucus vesiculosus [24], Ascophyllum nodosum [25], Sargassum kjellmanianum [26], Sargassum thunbergii [27], Cladosiphon okamuranus Tokida [28], in which the percentage of L-fucose ranged from 12.6 to 36.0 %, and the percentage of sulfate content from 8 to 25 %.…”