TY - JOUR
T1 - Characterization and antioxidant activity of selenium-containing phycocyanin isolated from Spirulina platensis
AU - Huang, Z.
AU - Guo, B. J.
AU - WONG, Ricky N S
AU - Jiang, Y.
N1 - Funding Information:
This research was supported by the Faculty Research Grant (FRG) of Hong Kong Baptist University.
PY - 2007
Y1 - 2007
N2 - Selenium-containing phycocyanin (Se-PC) and its different aggregates - monomer (αβ), trimer (αβ)3 and hexamer (αβ)6, which are represented as Se-PC1, Se-PC2 and Se-PC3, as well as their α and β subunits, were prepared and purified from selenium-rich Spirulina platensis. The Se speciation in Se-PC, its aggregates and subunits, as well as the antioxidant activities of these compounds against free radicals of superoxide, hydrogen peroxide and 2,2-diphenyl-1-picryl-hydrazyl (DPPH{radical dot}) were investigated. By gel filtration on SephadexG-200 column and SDS-PAGE, the molecular weight of Se-PC1, 2, and 3 were determined to be 38.5, 116 and 247 kDa, respectively, and these of α and β subunits were 17.8 and 19.5 kDa, respectively. Se concentrations of Se-PC1, 2 and 3 were of 197, 289 and 422 μg/g protein, respectively, and those of α and β subunits were 126 and 187 μg/g protein, respectively, which suggested that the Se content of Se-PC was decreased in the dissociation process of Se-PC and highly associated with its aggregation state. The antioxidant activities of Se-PC, its aggregates and subunits against different free radicals were found to be variable. Compared with phycocyanin without bound Se, although there were no differences among the DPPH{radical dot}-scavenging activities of Se-PC, its α and β subunits and the pure phycocyanin, the superoxide and hydrogen peroxide radical-scavenging activities of Se-PC, as well as Se-PC2 and Se-PC3, were significantly higher and proved to be positively correlated with their Se contents.
AB - Selenium-containing phycocyanin (Se-PC) and its different aggregates - monomer (αβ), trimer (αβ)3 and hexamer (αβ)6, which are represented as Se-PC1, Se-PC2 and Se-PC3, as well as their α and β subunits, were prepared and purified from selenium-rich Spirulina platensis. The Se speciation in Se-PC, its aggregates and subunits, as well as the antioxidant activities of these compounds against free radicals of superoxide, hydrogen peroxide and 2,2-diphenyl-1-picryl-hydrazyl (DPPH{radical dot}) were investigated. By gel filtration on SephadexG-200 column and SDS-PAGE, the molecular weight of Se-PC1, 2, and 3 were determined to be 38.5, 116 and 247 kDa, respectively, and these of α and β subunits were 17.8 and 19.5 kDa, respectively. Se concentrations of Se-PC1, 2 and 3 were of 197, 289 and 422 μg/g protein, respectively, and those of α and β subunits were 126 and 187 μg/g protein, respectively, which suggested that the Se content of Se-PC was decreased in the dissociation process of Se-PC and highly associated with its aggregation state. The antioxidant activities of Se-PC, its aggregates and subunits against different free radicals were found to be variable. Compared with phycocyanin without bound Se, although there were no differences among the DPPH{radical dot}-scavenging activities of Se-PC, its α and β subunits and the pure phycocyanin, the superoxide and hydrogen peroxide radical-scavenging activities of Se-PC, as well as Se-PC2 and Se-PC3, were significantly higher and proved to be positively correlated with their Se contents.
KW - Antioxidant activity
KW - Phycocyanin
KW - Selenium
KW - Spirulina platensis
UR - http://www.scopus.com/inward/record.url?scp=33745965062&partnerID=8YFLogxK
U2 - 10.1016/j.foodchem.2005.11.023
DO - 10.1016/j.foodchem.2005.11.023
M3 - Journal article
AN - SCOPUS:33745965062
SN - 0308-8146
VL - 100
SP - 1137
EP - 1143
JO - Food Chemistry
JF - Food Chemistry
IS - 3
ER -