STRUCTURE, MOLECULAR WEIGHT AND BIOACTIVITIES OF (1→3)-β-D- GLUCANS AND ITS SULFATED DERIVATIVES FROM FOUR KINDS OF LENT
Lentinan samples, (1→3)-β-D-glucans containing 4.6-15.2 wt% proteins, coded as L-I1, L-I2, L-I3 and L-I4 (L-I)were isolated from four kinds of Lentinus edodes. These glucans were treated with acetone to remove the protein in order to obtain free protein glucans coded as LNP-I1, LNP-I2, LNP-I3 and LNP-I4 (LNP-I). The free-protein polysaccharides were sulfated to give derivatives (S-LNP-I) with degree of substitution (DS) from 0.4-0.8. The structural features and weight- average molecular weight (Mw) of the samples were investigated by using infrared spectroscopy, elemental analysis,13C-NMR, size exclusion chromatography combined with laser light scattering (SEC-LLS) and viscometry. The effects of structure and conformation of the polysaccharides on antitumor activities were assayed in vivo (Sarcoma 180 solid tumors)and in vitro (Sarcoma 180, HL-60, MCF-7 and Vero tumors). The results indicated that the predominant species of the samples L-I and LNP-I in 0.2 mol/L NaCl aqueous solution existed as triple-helical chains with high rigidity and in dimethyl sulfoxide (DMSO) as single-flexible chains. Interestingly, the antitumor activities of LNP-I are lower than those of the native glucans (L-I), whereas their sulfated derivatives have higher inhibition ratio against Sarcoma 180 than LNP-I. The results reveal that the binding of protein, sulfated modification and the triple helix conformation are important factors in the enhancement of the antitumor activities of polysaccharides on the whole.
作 者： Unursaikhan Surenjav Li-na Zhang Xiao-juan Xu Mei Zhang Peter Chi Keung Cheung Fan-bo Zeng 作者单位： Unursaikhan Surenjav,Li-na Zhang,Xiao-juan Xu,Mei Zhang(Department of Chemistry, Wuhan University, Wuhan 430072, China)Peter Chi Keung Cheung(Department of Biological, The Chinese University of Hong Kong, Hong Kong, China)
Fan-bo Zeng(Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China)
刊 名： 高分子科学(英文版) ISTIC SCI 英文刊名： CHINESE JOURNAL OF POLYMER SCIENCE 年，卷(期)： 2005 23(3) 分类号： O6 关键词： (1→3)-β-D-glucans Lentinus Edodes Molecular weight Protein Sulfated derivative Antitumor activity