Marine Algae Functional Protein Purification, Characterization And Its Applications

Firstly, R-phycoerythrin was isolated and purified from the red alga, Polysiphonia urceolata Grev, or Porphyra haitanensis using Streamline column combined with ion-exchange chromatography or hydroxyapatite chromatography. Then, C-phycocyanin was purified from the Spirulina platensis using the same technology. The absorption spectra and the fluorescence spectra of these pigment protein were consistent with the typical spectra of phycobiliproteins. SDS–PAGE or LC-ESI-MS showed they conform to the published data of phycobiliproteins. The method described here was a scaleable technology that allows large quantity of phycobiliproteins to be recovered from the unclarified alga crude extract. It was a high protein recovery technology while reducing both processing costs and times. The very important point is that using of this new novel method, block of chromatographic column due to the abundance of polysaccharide in alga could be overcomed successfully. One cycle of the isolation process by EBA chromatography, including equilibration (30 min) + loading (60 min) + washing (50 min) + elution (60 min), took only about 3.5 h. Only one step, we can get the fractions could be used as food additives and cosmetics additives.Four different chitosan microspheres (CS-CL) were prepared by suspension crosslinking method and used as carriers of phycobiliproteins. In this study, phycobiliproteins were loaded in the microspheres and released in vitro. The basic loading and releasing behavior for phycobiliproteins of these kind of new microspheres were also investigated. The results showed that all these chitosan microspheres have the ability to controlrelease of phycobiliproteins.A lectin presented in the marine green alga Bryopsis hypnoides was purified using affinity chromatography on Fetuin-agrose column and then partially characterized. N-terminal 15 amino acid sequence and LC-ESI-MS analysis of this lectin did not show sequence significant homology with those lectins or with any other proteins reported in public protein data bases, which indicated that the lectin belongs to a novel protein family.The chemical conjugation between R-phycoerythin and a lectin from a green alga Bryopsis hypnoides was studied. Results showed that there was a fraction possessed good optical properties and hemagglutinating activity. However, electrophoresis assay did not indicate the combination of these two molecules.