From Saline Habitats to Sustainable Bioactive Polymers: Physicochemical and Biological Insights into Water Extracts from Salicornia Neei Lag

Abstract

This study examines the extreme halophytic plant Salicornia neei Lag., found on the Chilean Pacific coastline, as a novel and sustainable source of highly functional polysaccharides. Polysaccharide extraction was performed using a green approach in water under mild conditions, thereby significantly minimizing energy consumption. Comprehensive characterization revealed an arabinose pectic polysaccharide (36 kDa, 34% methylation). Notably, acetylated units, constituting 25% of the polysaccharide structure, were detected in any Salicornia plant extract for the very first time. The extract demonstrated outstanding emulsification activity, achieving an impressive emulsion index of above 70% with a concentration of just 1% across five diverse edible oils (corn, canola, avocado, sunflower, and sesame). This superior performance, likely attributed to the detected acetyl groups, positions it as a potent, natural, and clean-label alternative to conventional, often synthetic, emulsifiers. Furthermore, the extract exhibited remarkable antioxidant capacities (89.47% DPPH, 71.64% ABTS, 45.40% hydroxyl radical scavenging, and 98.56% ferrous ion chelation), as well as significant antimicrobial activity against B. cereus and R. eutropha. Notably, the extract showed no cytotoxicity against healthy human fibroblast cells, confirming its safety, while displaying promising selective antitumoral activity (IC50 = 910 µg/mL; SI = 3.89) against colon cancer cells (HCT-116). Overall, these findings strongly suggest that the Salicornia neei from the Pacific Ocean represents a unique source of water-extractable polysaccharides, whose demonstrated superior biological activities—including groundbreaking emulsification, robust antioxidant and antimicrobial effects, and selective anticancer properties—collectively underscore its multifunctional potential as an innovative ingredient for diverse food, nutraceutical, and pharmaceutical applications.