菜籽多糖WPS-1的理化性质及结构研究

Physico-chemical and Structural Characterization of Rapeseed Polysaccharide WPS-1

菜籽多糖WPS-1为白色絮状的非淀粉多糖,其中性糖、糖醛酸、蛋白质含量分别为83.2%、6.1%、3.4%,而WPS-1中蛋白质部分由13种氨基酸组成。经FT-IR、GC分析WPS-1的官能团特征和单糖组成,确定WPS-1单糖主要由阿拉伯糖(Ara)、半乳糖(Gal)、葡萄糖(Glc)组成,其物质的量分数分别为67.7%、17.8%、14.5%;通过甲基化分析得出WPS-1的主体部分是主要是由(1→5)键和(1→2)键连接的阿拉伯糖残基组成的多支链α-阿拉伯糖。13CNMR和1HNMR验证WPS-1中阿拉伯糖部分含有4种糖环。

WPS-1 was found to be a non-starch polysaccharide with white and flocculent appearance,in which the contents of neutral sugar,uronic acid and protein were 83.2 %,6.1% and 3.4%,respectively.Protein in WPS-1 was composed of 13 different amino acids.The major monosaccharide compositions of WPS-1 as determined through FT-IR and GC analyses were Ara（67.7%）,Gal（17.8%） and Glc（14.5%）.The methylation analysis indicated that the major fragments of WPS-1 were（1 →5） and（1 →2） linked by Ara residues of α-arabinoses.Four kinds of substituted arabinosyl residues as verified according to the 13C NMR and 1H NMR spectra existed in arabinan fragments of WPS-1.