抄録
Phycobiliproteins were purified and characterized from an edible cyanobacterium, Nostochopsis sp. C-phycocyanin and allophycocyanin were simultaneously purified by about 3.9- and 4.3-fold to provide yields of 23 and 29%, respectively, from cell extracts using simple purification steps, such as ammonium sulfate fractionation and anion exchange chromatography. The purified preparation was eluted as a single peak with an apparent molecular mass of 117.0 kDa during a gel filtration. Polyacrylamide gel electrophoresis of the purified preparation yielded a single protein band in the absence of SDS, but in the presence of SDS, three protein bands with apparent molecular masses of 18.5, 16.5 and 15.5 kDa were formed. These results suggest that the purified preparation consists of C-phycocyanin and allophycocyanin, both of which were strongly associated with one another during purification. Furthermore, the purified Nostochopsis preparation (1 mg·mL-1) showed considerable antioxidant capacity (11.6 μmol·L-1 trolox equivalent), which was similar to that (10.5 μmol·L-1 trolox equivalent) of Spirulina C-phycocyanin.