Key Laboratory of Coarse Cereal Processing (Ministry of Agriculture and Rural Affairs), Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, Sichuan, China; Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an 625014, Sichuan, China.
Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an 625014, Sichuan, China.
Int J Biol Macromol. 2022 Nov 1;220:97-108. doi: 10.1016/j.ijbiomac.2022.08.058. Epub 2022 Aug 13.
The present study aimed to evaluate the influence of ultrasound assisted HO/ascorbic acid reaction on the structural characteristic and immunostimulatory activity of a β-D-glucan isolated from D. indusiata, so as to reveal its potential structure-immunostimulatory activity relationship. A purified β-D-glucan, named as DP, was quickly isolated from D. indusiata, and further identified as a 1,3-β-D-glucan with 1,6-β-D-Glcp as branched chains, which exhibited a rigid rod chain conformation in 0.9 % (w/v) of NaCl solution. Furthermore, results showed that the primary structure of DP was overall stable after the degradation by ultrasound assisted HO/ascorbic acid reaction. However, the molar mass and chain conformation of DP obviously changed. In addition, DP and its degraded products exerted remarkable immunostimulatory activity in vitro and in vivo, which could activate the nuclear factor-κB (NF-κB) signaling pathway through toll-like receptor 4 (TLR4). Indeed, the immunostimulatory activity of DP was closely-correlated to its molar mass and chain conformation. An appropriate degradation of molar mass could promote its immunostimulatory activity. While the transformation of chain conformation from rigid rod to random coil could cause the significant decrease of its immunostimulatory activity. These findings are beneficial to better understanding the structure-immunostimulatory activity relationship of β-D-glucans from edible mushrooms.
本研究旨在评估超声辅助 HO/抗坏血酸反应对从姬松茸中分离得到的 β-D-葡聚糖的结构特征和免疫刺激活性的影响，从而揭示其潜在的结构-免疫刺激活性关系。从姬松茸中快速分离出一种纯化的β-D-葡聚糖，命名为 DP，并进一步鉴定为 1,3-β-D-葡聚糖，其 1,6-β-D-Glcp 为支链，在 0.9%（w/v）NaCl 溶液中呈现刚性棒链构象。此外，结果表明，超声辅助 HO/抗坏血酸反应降解后 DP 的一级结构总体稳定。然而，其摩尔质量和链构象明显发生了变化。此外，DP 及其降解产物在体外和体内均表现出显著的免疫刺激活性，可通过 Toll 样受体 4（TLR4）激活核因子-κB（NF-κB）信号通路。事实上，DP 的免疫刺激活性与其摩尔质量和链构象密切相关。适当的摩尔质量降解可促进其免疫刺激活性。而链构象从刚性棒到无规线团的转变会导致其免疫刺激活性显著下降。这些发现有助于更好地理解食用蘑菇中β-D-葡聚糖的结构-免疫刺激活性关系。
