香菇不同发育阶段子实体多糖的理化性质及体外免疫活性研究

香菇多糖是从香菇菌丝体或子实体中提取纯化得到的高分子葡聚糖,作为香菇主要的生物活性物质,具有提高免疫力、抗病毒、抗氧化和抗真菌等生物活性。本研究对幼菇期、菌褶期、采收期、成熟期和开伞期5个不同发育阶段香菇粗多糖含量、理化性质和体外免疫活性进行比较分析。结果表明,其粗多糖含量、理化性质和体外免疫活性具有明显差异。粗多糖得率呈现先增加后降低的趋势,菌褶期得率最高;粗多糖含量也呈现先增加后降低的趋势,成熟期含量最高;多糖的分子量因发育期不同而有较大差异,发育后期所得粗多糖分子量千万级以上组分的比例增加,分子量百万级和十万级的多糖组分比例降低;不同发育阶段香菇子实体多糖的单糖组成均包含果糖、半乳糖、葡萄糖和甘露糖4种单糖,且都以葡萄糖为主;5个阶段的多糖组分均有较好的体外免疫活性,其中幼菇期粗多糖在浓度500μg/mL时表现出最高的体外免疫活性。本研究探讨了香菇不同发育阶段子实体多糖的理化性质及体外免疫活性,为香菇采收期的确定及香菇多糖的制备与利用提供理论依据。

Physico-chemical properties and immunocompetence in vitro of polysaccharides of Lentinula edodes fruiting bodies at different growth stages

Lentinan is a macromolecule glucan extracted and purified from mycelia or fruiting bodies of Lentinula edodes, having biological activities of improving immunity, anti-virus, anti-oxidation and anti-fungus. In this study, physico-chemical properties and immunocompetence in vitro of polysaccharides of Lentinula edodes at different growth stages of fruiting bodies were compared and analyzed. The results showed that the content, physico-chemical properties and in vitro immunocompetence of crude polysaccharides varied with growth stage of fruiting bodies. The yield of crude polysaccharides first increased at early stage and high-yielded at gill-formation stage and then decreased. The content of crude polysaccharides showed the same trend, but the highest content appeared at mature stage. The molecular weight of polysaccharides varied greatly with growth stages. The proportion of polysaccharides with molecular weight of ten millions or more increased, while that with molecular weight of millions or less decreased at later stage. The monosaccharide components of polysaccharides at different stages were constantly fructose, galactose, glucose and mannose. All the polysaccharides obtained from different growth stages had good immunocompetence in vitro, of which those from button stage showed the highest activity at concentration of 500μg/mL. These results provided referential estimation for determination of harvest period and preparation of lentinan products.