Potential of fibrous adsorbents for the binding and characterization of Porphyridium purpureum bioactive polysaccharides

摘要

BACKGROUND: Complex polysaccharides are important in the pharmaceutical industry, yet, due to their large molecular weight and reduced charges, their purification is a highly demanding process that requires binding matrices with unique properties. This work demonstrates for the first time that complex polysaccharides biosynthesized by microalga Porphyridium purpureum can be adsorbed onto Q fibrous anion exchangers. RESULTS When the polysaccharides were characterized, the extent of sulfation was higher in native polysaccharides than in ethanol- or alkali-extracts. The zeta potentials increased with increasing pH and the highest charge was observed at pH 8, while the Z-average diameters of the polysaccharide at pH 6 were highest for alkali-extracts. Instead of pellicular resins, Q fibrous adsorbents were used to determine Langmuir thermodynamic properties and dynamic binding capacities. The parameters included static binding capacity and dissociation constant of 13.47 ± 1.02 mg g~(-1) and 0.141 ± 0.027 mg mL~(-1), and 10 and 50% breakthrough capacities of 4.46 ± 0.22 and 5.51 ± 0.28 mg g~(-1), respectively. The antiviral activity of the polysaccharides was demonstrated byminimizing bacteriophage lysis of Streptococcus thermophilus. CONCLUSION This work demonstrates that polysaccharide extraction can be optimized and the adsorption and desorption of a complex polysaccharide ontoQfibrous matrix is feasible. These parameters could be exploited for up-scaling of polysaccharides for nutraceutical and pharmaceutical applications.