Photosynthetic Pigment and Carbohydrate Profiling of Fucus vesiculosus from an Iberian Coastal Lagoon

Abstract

Fucus vesiculosus is a brown seaweed with applications in the food, pharmaceutic, and cosmetic industries. Among its most valuable bioactive compounds are the pigment fucoxanthin and polysaccharides (e.g., fucoidans). In this study, we profiled the photosynthetic pigments and carbohydrates of F. vesiculosus from six locations along the Ílhavo Channel in the Iberian coastal lagoon of Ria de Aveiro, Portugal. Photosynthetic performance (Fv/Fm), pigment, and carbohydrate concentrations were similar between locations, despite differences in environmental factors, such as salinity and periods of exposure to desiccation. Concentration of total carbohydrates (neutral sugars + uronic acids) averaged 418 mg g−1 dw. Fucose was the second most abundant neutral sugar, with an average concentration of 60.7 mg g−1 dw, indicating a high content of fucoidans. Photosynthetic pigments included chlorophylls a and c, β,β-carotene, and the xanthophylls fucoxanthin, violaxanthin, antheraxanthin, and zeaxanthin. Concentrations of fucoxanthin were higher than those reported for most brown macroalgae, averaging 0.58 mg g−1 dw (65% of total carotenoids). This study indicates that F. vesiculosus from Ria de Aveiro is a valuable macroalgal resource for aquaculture companies operating in the region, with considerable potential to yield high-value bioactive compounds.

Fucus vesiculosus-Rich Extracts as Potential Functional Food Ingredients: A Holistic Extraction Approach

“…It was also possible to see the presence of sulphates, accounting for 5.8% of the DW of F. vesiculosus biomass (Table 1). Therefore, the carbohydrate composition herein described is consistent with the presence of different polysaccharides in F. vesiculosus, as reported for this species [11,37,38] or brown seaweeds in general [1,13,39,40].…”

“…These results are in the upper range of fucoxanthin content reported for brown seaweeds [46]. The fucoxanthin content in the 1_EtOH_70%_Sn extract was found to be consistent with that reported in ethanol extracts (0.09 g/100 g algae DW) in the same species [47], as well as when different organic solvents were used, including acetone (0.06 g/100 g algae DW) and methanol (0.08 g/100 g algae DW) [23,38,48]. These findings allow us to suggest that pre-aqueous extraction before using 70% EtOH in the first approach enhanced fucoxanthin recovery, whereas pre-ethanolic extraction (96% EtOH) in the second approach proved detrimental to its recovery.…”