Purification of C-phycocyanin from Spirulina (Arthrospira) fusiformis.

C-phycocyanin was purified from Spirulina (Arthrospira) fusiformis by a multi-step treatment of the crude extract with rivanol in a ratio 10:1 (v/v), followed by 40% saturation with ammonium sulfate. After removal of rivanol by gel-filtration on Sephadex G-25, the pigment solution was saturated to 70% with ammonium sulfate. After the last step of purification, C-phycocyanin had an emission and absorption maxima at 620 and 650 nm, respectively and absorbance ratio A(620)/A(280) of 4.3, which are specific for the pure biliprotein. Its homogeneity was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, yielding two bands of molecular masses 19500 and 21500 kDa, corresponding to alpha and beta subunits of the pigment, respectively. The yield of C-phycocyanin was approximately 46% from its content in the crude extract.

An IgA, IgG and IgM-containing human immunoglobulin for oral administration to high-risk bottle-fed newborns. I. Immunochemical characterisation and antibody activity.

Antibodies to a wide spectrum of infectious agents belonging to the IgA, IgM and IgG isotypes are thought to be one of the protective factors in human milk. Cow milk-fed newborns are at an increased risk of infections as well as of allergic diseases and of necrotising enterocolitis. A reasonable approach would be to add to the milk formula fed to them the immunoglobulins present in human milk. We developed a pasteurised immunoglobulin preparation from pooled donor plasma ('Orabulin') containing 75% IgG, 18% IgA and 6% IgM for feeding to high-risk bottle-fed babies. Its molecular composition was studied by HPLC and by SDS-PAGE. The levels of IgA, IgG and IgM antibodies in Orabulin were compared to these in the immunoglobulin fraction of human colostrum and an enrichment was found. It is suggested that the presence of a standardised amount of human IgM in an immunoglobulin preparation intended for feeding to newborns may bring an additional advantage because of the high opsonising and virus-neutralising activity of the antibodies of this isotype.