Chemical and microstructural characterization of three seaweed species from two locations of Veracruz, Mexico

Abstract Seaweeds or marine macroalgae are sources of industrial important macro compounds. This work characterizes the chemical composition, morphology, cellular structure, morphometric parameters, protein distribution, density, and quantifies the chemical elements of three seaweed species. The morphological characterization performed by Digital Image Analysis (DIA) showed that the length/width ratio for UF (Ulva fasciata) (15.4/10.9 cm) was greater compared to SC (Sargassum cymosum) and GS (Grateloupia subpectinata) (8.9/7.6 cm and 87/5.3 cm). Using Schiff's and Coomassie blue reagents, identified carbohydrates and proteins in cells and protein bodies (PB). Cell morphology showed larger cells in the SC cortex (457.8 µm2) and smaller cells in the SC meristoderm (80.5 µm2). PB density (PB/area) and distribution (area occupied by the cell, %) were higher in the cortex of GS (10468 PB/mm2, 20%) and lower in the meristoderm of SC (917 PB/mm2, 7%). Chemical analysis showed as major compounds: carbohydrates (12-46%), ashes (13-42%), and proteins (6-17%). Meanwhile, the concentration of metals was below the toxicity level. These results contribute to the knowledge of the structure-function relationship of seaweeds metabolites which could be a source of compounds of interest for the industrial sector.