对生长期为25、35、45 d的金耳子实体(Naematelia aurantialba)多糖(分别编号为NAP-1、NAP-2、NAP-3)的得率、多糖含量、糖醛酸含量、分子量分布特征、单糖组成及体外抗炎活性进行比较.结果表明,NAP-3的得率(34.50%)最高,多糖与糖醛酸含量显著高于NAP-1.随着生长期的延长,子实体多糖的重均分子量(weight average molecular weight,Mw)由1.859×106g·mol-1降低至1.347×106g·mol-1.单糖组成分析结果表明,子实体多糖是一种由木糖、甘露糖、葡萄糖醛酸以及少量葡萄糖组成的酸性杂多糖.不同生长期的金耳子实体多糖均能抑制脂多糖诱导引起的RAW264.7巨噬细胞NO释放与炎症因子分泌,与NAP-2、NAP-3相比,NAP-1抑制效果最强.通过Pearson相关性分析,发现金耳子实体多糖的体外抗炎活性与其Mw和甘露糖的摩尔百分比呈正相关,与木糖的摩尔百分比呈负相关.研究结果可为采收获得高抗炎活性的金耳子实体提供技术参数,对金耳健康产品的开发利用提供参考.
Effects of Cultivation Time on Structural Characteristics and Anti-Inflammatory Activity of Polysaccharides from Naematelia aurantialba
Polysaccharides were extracted from fruiting bodies of Naematelia aurantialba at 25 d,35 d and 45 d of cultivation,and were numbered NAP-1,NAP-2 and NAP-3,respectively.NAP-1,NAP-2 and NAP-3 were then compared for yield,polysaccharide content,glucuronic acid content,molecular weight distribution,monosaccharide composition,and anti-inflammatory activity in vitro.The results showed that NAP-3 had the highest yield of 34.50%,and its polysaccharide and glucuronic acid contents were higher than those of NAP-1.As the growth time extended,the weight average molecular weight(Mw)of N.aurantialba polysaccharides(NAPs)decreased from 1.859×106g·mol-1 to 1.347×106g·mol-1.Monosaccharide composition analysis revealed that NAPs were acidic heteropolysaccharides composed of xylose,mannose,glucuronic acid(GlcA),and a small amount of glucose.All three NAPs inhibited NO release and inflammatory factor secretion in RAW264.7 macrophages induced by lipopolysaccharide(LPS).Compared with NAP-2 and NAP-3,the anti-inflammatory efficacy of NAP-1 was better.Pearson's correlation analysis showed that the in vitro anti-inflammatory activity of N.aurantialba was positively correlated with Mw and the molar percentage of mannose,but negatively correlated with the molar percentage of xylose.These findings provided a reference for harvesting N.aurantialba fruiting bodies with high anti-inflammatory activity,and the development of N.aurantialba healthcare products.