超声-高温热水提取香菇多糖及其产物特性研究

Characteristics of Lentinan Polysaccharide Extracted by Ultrasonic Wave and Hot Water

本文采用超声-高温热水提取香菇多糖(第一步采用超声温度62℃,时间50min,功率640W,第二步高温热水提取温度120℃,时间40 min),得率达到了15.57±0.83%,是传统水提法(11.22%)的1.39倍,大大提高了香菇多糖的得率。与第一步提取多糖相比,第二步提取的多糖纯度较高(为91.98%),蛋白含量较少,分子量测定为单一峰(分子量为3.7×105Da),粘度较小。在刚果红实验中两种多糖都发生了红移现象,而且第一步提取多糖比第二步提取的多糖红移效果更显著,表明超声提取多糖的三螺旋结构更加完整。通过扫描电子显微镜进行观察,进一步验证了刚果红实验结果。红外光谱检测表明两种多糖的官能团组成无显著性差异。

The extraction of lentinan polysaccharides by Ultrasonic wave used in the first step（62 ℃, 50 min, 640 W） and hot water used in the second step （120 ℃, 40 rain） was investigated. The extraction yield reached 15.57±0.83%, being 1.39 times of that of the polysaccharides prepared by traditional water extraction. After the first extraction step, the polysaccharides was further extracted by high-temperature water, giving higher purity of 91.98%, a smaller molecular weight of 3.7±105 Da and viscosity of 1.07 pa.s. A red shift phenomenon was observed when conducting Congo red experiments. The polysaccharides extracted in the first step showed an evident red shift, indicating that the polysaceharides extracted by ultrasound had complete triple helix structure, which were further confirmed by a scanning electron microscope. Infrared spectra showed that the chemical structural of the two polysaecharides had no significant difference.