The sulfated polysaccharide from a marine red microalga as a platform for the incorporation of zinc ions

The cell-wall sulfated polysaccharide of the marine red microalga Porphyridium sp. is a high molecular weight biopolymer that has potential for use as a platform for metal complexation for various applications. This paper describes the structural and rheological characterization and antibacterial activity of the polysaccharide in combination with Zn²⁺ (Zn-PS). SAXS and rheology studies indicate that with the addition of ZnCl₂ to the sulfated polysaccharide the only change was the increase in viscosity in the entangled regime. The antibacterial activity of Zn-PS solutions was more potent than that of the native polysaccharide against Gram-negative and Gram-positive bacteria. The synergy between the bioactivities of Zn²⁺ (which is a key player in wound healing and is active against variety of pathogens) and the unique bioactivities of the polysaccharide (e.g., anti-inflammatory) indicates promising potential for the development of novel products for the pharmaceutical and cosmetics industries.