Research On The Extraction, Purification And Antitumor Immune Activity Of C-phycocyanin From Spirulina Platensis (Arthraspira Platensis)

Natural products have been the mainstay of cancer chemotherapy in the past 30 years. Blue-green algae Spirulina platensis (Arthraspira platensis) is gaining more and more attentions as a nutraceutical and source of potential pharmaceuticals. The biological and pharmacological properties of Spirulina were attributed mainly to C-Phycocyanin (CPC). CPC, a non-toxic water-soluble fluorescent protein pigment, is one of the major components of Spirulina platensis. Recent studies have demonstrated the antioxidant, antimutagenic, antiviral, anticancer, anti-allergic, immune enhancing, hepato-protective, blood vessel relaxing and blood lipid-lowering effects of CPC, while the underlying functionary mechanism of antitumor immune activity have not been made clear, so we engaged in this aspect of work..In our study, the methods of extraction and purification of CPC from Spirulina platensis were firstly improved. Through repeatedly freezing and thawing alternatively in the presence of phosphate buffer combined with ultrasonic fragmentation, the CPC is efficiently extracted by being precipitated in 50% (W/V) solid ammonium sulphated resulting in 13.1% recovery of C-phycocyanin. Then, the crude phycocyanin is chromatographed by hydroxylapatite (HA) column, further purified by sephacrylS-200HR gel chromatography and HA column chromatography again .In the end, the CPC with a high purity (A620/A280) of 4.71 is obtained. Analyzed by 12% SDS-PAGE electrophoresis, CPC migrates as two bands corresponding to its two subunits (αandβ) and the molecular weight is 17.0ku and 21.4ku, respectively. Results showed that we get the CPC with a comparatively high extracting rate and a high purity by means of a series of extraction and purification procedures.Then the antitumor immune activity of CPC were explored, which is composed of five aspects:①Studying on the antitumor activity of CPC in vitro. The effects of C-phycocyanin from Spirulina platensis on the growth of four kinds of human cancer cells (HeLa, MCF, NKM, SVOA) and one strain of normal cell (HEL) are studied by MTT assay. The results show that the C-phycocyanin could significantly inhibit the growth of these cancer cells to different extent in a dose and time dependent manner.