粉碎细度对灵芝子实体水提物中多糖组成和体外免疫活性的影响

Effect of Particle Size on the Extraction,Molecular Character and In Vitro Immunological Activityof Polysaccharides from Ganoderma lucidum Fruit Bodies

采用普通机械粉碎和超微粉碎法获得子实体碎块(1.0cm×0.5cm)和不同细度(10~200目)的灵芝(Ganoderma lucidum)子实体粉,对其提取物得率、多糖含量、相对分子质量分布特征、单糖组成及体外免疫活性等进行了系统比较分析。结果表明,实验范围内,随子实体粉细度增加,提取物的得率和多糖含量也提高,相对分子质量为2×10~6~3.5×10~6的多糖组分在提取物中所占比例增加。与子实体碎块相比,当粉体达到100目时,水提物总得率从6.41%提高到7.89%,增加了23.1%;而30%乙醇沉淀部分得率由原来的0.67%升高到2%以上,提高了2倍。单糖组成分析结果显示,30%乙醇沉淀的大分子多糖(30E)主要为葡聚糖,70%乙醇沉淀多糖(70E)主要含有半乳糖和葡萄糖,另外还含有少量的岩藻糖、甘露糖和葡萄糖醛酸,增加粉碎细度对70E部分的单糖组成没有显著影响。与70E部分相比,30E部分均表现出较好的刺激巨噬细胞释放NO的活性。

Ganoderma lucidum fruit body samples of different particle size(1.0 cm×0.5 cm fragments,10,60,100 and 200 mesh powder)were obtained by mechanical fragmentation and superfine pulverization technology.After hot water extraction and addition of absolute ethanol to final concentrations of 30%,50%and 70%,samples were allowed to stand for 6 h at 4℃and the precipitated material was collected by centrifugation at 8000 g for 15 min to give crude polysaccharide fractions 30E,50E and 70E,respectively.Crude polysaccharide yields,the content,molecular characteristics and monosaccharide composition of the extracted polysaccharides,and the immune-enhancing activity of the fractions were systematically compared.Crude polysaccharide yields and the polysaccharide content of the fractions,especially polysaccharide material with a molecular weight ranging from 2×10 6 to 3.5×10 6 g/mol,were significantly higher the smaller the particle size.The total hot water extract yield from 100 mesh fruit body powder was 23.1%higher than the corresponding yield obtained from 1.0 cm×0.5 cm fragments,and the corresponding 30E crude polysaccharide yield was more than double.Monosaccharide composition analysis revealed that high molecular weight polysaccharide material precipitated with 30%ethanol were composed entirely of glucose.Lower molecular weight polysaccharides precipitated with 70%ethanol were composed mainly of galactose and glucose together with small amounts of fucose,mannose and glucuronic acid.A decrease in particle size had no obvious effect on the monosaccharide compositions of 70E polysaccharides.However,30E fractions obtained from all five fruit bodies samples were more effective in increasing NO production by macrophages compared with the corresponding 70E fractions.