ABSTRACT
The sustainable use of marine resources is a competitive advantage of the most developed countries, which has a positiveimpact on the economic and social development of their populations. Currently, marine organisms such as macroalgaeare an important source of functional compounds such as polysaccharides, proteins, unsaturated and polyunsaturatedfatty acids, among others, with nutritional value and pharmacological properties. Gracilariopsis tenuifrons is amacroalga found in the Colombian Caribbean Sea, which has been neither chemically nor physicochemically studied;therefore, the aim of this study was to evaluate the polysaccharides composition and nutrients contents of crudeextract and its UV radiation absorption capacity. The purification was carried out by ultrafiltration using membranesof molecular size exclusion 100, 50, 10, and 3 kDa. The chemical characterization was done by gel electrophoresis,Nuclear Magnetic Resonance, Fourier Transform Infrared Spectroscopy, and the particle size and potential zeta byDynamic Light Scattering. The absorption coefficient (absorbance/g dry sample) was measured at 290, 310, 340, and380 nm. Sulfated and non-sulfated polysaccharides were detected in the fractions and identified as polysaccharidestype k, and β-carrageenan and alginate. The proximate analysis showed that the total content of protein, carbohydrates,fat, and calories is 15.58%, 69.81%, 0.15%, and 342.94% Kcal, respectively. The crude extracts showed an importantabsorption coefficient in UVB-UVA range. The findings suggest that G. tenuifrons seaweed propagated in vitro is aviable candidate of natural additives, such as phycocolloids and bioactive compounds, for designing new functionalproducts in the pharmaceutical and cosmetic industry, in addition to its nutritional properties to be used in foods.