Studies On The Isolation And Purification Of Polypeptides From JNY And The Determination Of Their Antitumor Activities

This papa reports the studies on the isolation, purification and their antitumoractivities of polypeptides from marine-JNY.The purified polypeptides JNY-1 and JNY-2 were obtained from JNY by the technologies of homogenization, ammonia sulfate precipitation, ion exchange chromatography and Sephadex G-50 gel filtration chromatography. The purity of the final products is over 97% detected by RP-HPLC. The single band was given in SDS-PAGE and IEF. Their M.W. measured by SDS-PAGE were 16883.4Da and 13189.7Da, isoelectric point were 5.3 and 5.7 respectively. The UV absorption spectrum and amino acid constituents of the purified products were also detected. Phenol-vitriol test revealed that saccharides exist in JNY-1.The primary pharmacological experiments indicated that the totle polypeptides from JNY exhibited markedly antitumor activities in vivo and the tumor inhibitory rate on S₁₈₀-bearing mice was 79.60%. The purified polypeptides JNY-1 and JNY-2 may both inhibit the growth of tumor cells Glc-82 in vitro, and the IC₅₀ values were 23.33μg/ml and 9.59μg/ml respectively measured by MTT assay.