Institute of Agro-Products Processing and Nuclear-Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Shanxi Key Laboratory of Edible Fungi for Loess Plateau， Jinzhong 030801, China.
Institute of Agro-Products Processing and Nuclear-Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.
Int J Biol Macromol. 2023 Jul 31;244:125426. doi: 10.1016/j.ijbiomac.2023.125426. Epub 2023 Jun 15.
The carbon source, an essential factor for submerged culture, affects fungal polysaccharides production, structures, and activities. This study investigated the impact of carbon sources, including glucose, fructose, sucrose, and mannose, on mycelial biomass and the production, structural characterization, and bioactivities of intracellular polysaccharides (IPS) produced by submerged culture of Auricularia auricula-judae. Results showed that mycelial biomass and IPS production varied with different carbon sources, where using glucose as the carbon source produced the highest mycelial biomass (17.22 ± 0.29 g/L) and IPS (1.62 ± 0.04 g/L). Additionally, carbon sources were found to affect the molecular weight (Mw) distributions, monosaccharide compositions, structural characterization, and activities of IPSs. IPS produced with glucose as the carbon source exhibited the best in vitro antioxidant activities and had the strongest protection against alloxan-damaged islet cells. Correlation analysis revealed that Mw correlated positively with mycelial biomass (r = 0.97) and IPS yield (r = 1.00), while IPS antioxidant activities correlated positively with Mw and negatively with mannose content; the protective activity of IPS was positively related to its reducing power. These findings indicate a critical structure-function relationship for IPS and lay the foundation for utilizing liquid-fermented A. aruicula-judae mycelia and the IPS in functional food production.
碳源是影响真菌多糖产生、结构和活性的重要因素。本研究考察了不同碳源（葡萄糖、果糖、蔗糖和甘露糖）对黑木耳液体培养中菌丝体生物量和胞内多糖（IPS）产生、结构特征及生物活性的影响。结果表明，不同碳源对菌丝体生物量和 IPS 产量有影响，其中葡萄糖为碳源时菌丝体生物量（17.22±0.29 g/L）和 IPS 产量（1.62±0.04 g/L）最高。此外，碳源还影响 IPS 的分子量（Mw）分布、单糖组成、结构特征和活性。以葡萄糖为碳源生产的 IPS 具有最佳的体外抗氧化活性，对胰岛细胞损伤的保护作用最强。相关性分析表明，Mw 与菌丝体生物量（r=0.97）和 IPS 产量（r=1.00）呈正相关，而 IPS 抗氧化活性与 Mw 呈正相关，与甘露糖含量呈负相关；IPS 的保护活性与还原力呈正相关。这些发现表明 IPS 存在重要的结构-功能关系，为利用液体发酵黑木耳菌丝体和 IPS 生产功能性食品奠定了基础。
