Abstract: SCAI-c, another angiogenesis inhibitor from shark cartilage of Guangdong Yangjiang, was purified and the bioactivity of SCAI-c were investigated. The 1. 0 mol/Lguanidine and 0. 02 mol/L MES(at 28 ℃) extracts of shark cartilage was centrifuged at 6000 r/min for 30 min and the pellet was discarded, and the supernatant was recentrifuged at 12000 r/min for 30 min, then ultrafiltrated and fractionally precipitated with 25%-90% acetone. The precipitate was applied to a Sephadex G-75 gel column and eluted after the predominand peak of A_280nmabsorbing material with 0. 05 mol/L Tris-HCl buffer (containing 0.02 mol/L NaCl and 0. 02% NaN₃). The material Bwere composed of three single peptides with molecular mass of 17600, 15000, 12600, then were purified by using reverse-phase HPLC, the eluate of Cwas collected, dried and observed by chicken chorioallantoic membrane. The pure inhibitor was homogeneous as a single band on a silver-stained 12. 5% sodium dodecyl sulfate-polyacrylamide gel. SCAI-c has a molecular weight of 17600, and could specifically inhibit angiogenesis of the chorioallantoic membrane of chick embryos, and the inhibitory effect of angiogenesis was SCAI-c concentration dependent, but the concentration of SCAI-c increased to 0. 5 μg/μL, chick embryos died about to 20%-30%. Inhibitory characteristic of SCAI-c was similar with that of SCAI-a. They are specific angiogenesis inhibitor, and may be a useful drug on tumor therapy in some day.

Key words: Shark cartilage, Angiogenesis inhibitor, Separarion and purification, Bioactivity, Chorioallan-toic membrane of chick embryos