李凤兰¹，吴天祥^1，2*，邓代霞¹，袁丹丹¹，江守发¹

（1.贵州大学酿酒与食品工程学院，贵州贵阳 550025；2.贵州食品工程职业学院，贵州贵阳 551400）

摘要：为探讨太子参乙醇提取物参与灰树花发酵及其促胞外多糖增加的机理。本试验开展太子参乙醇提取物对灰树花生物量、胞外多糖的影响研究；动态分析灰树花发酵期间多糖合成关键酶活性的变化，同时，从氧化应激角度探讨太子参乙醇提取物的添加对菌丝体生长及胞外多糖的影响。试验表明：太子参85%乙醇提取物添加量为9 g/L，发酵7 d，生物量和胞外多糖含量均达到峰值（P＜0.01），与未添加太子参乙醇提取物的相比，分别增加了53.20%和50.71%；动态分析灰树花多糖合成关键酶的变化，发现在灰树花发酵体系中添加太子参85%乙醇提取物后，发酵7 d，灰树花胞内磷酸葡萄糖变位酶（PGM）、UDP-葡萄糖焦磷酸化酶（UDPG）和磷酸葡萄糖异构酶（GPI）活性达到最高，与未添加太子参乙醇提取物相比，PGM、UDPG 活性分别提高9.44%、18.57%，GPI 活性降低19.46%（P＜0.05）；添加太子参乙醇提取物的灰树花胞内活性氧水平（ROS）、丙二醛（MDA）、过氧化氢（H₂O₂）含量变高，超氧化物歧化酶（SOD）、谷胱甘肽过氧化酶（GSH-P_x）、过氧化氢酶活性（CAT）增强，与未添加太子参乙醇提取物相比，其含量或酶活性均显著提高（P＜0.05）。该研究表明太子参85%乙醇提取物参与灰树花发酵时，通过调节多糖合成酶活性促胞外多糖增加，同时，太子参乙醇提取物对灰树花生长有胁迫作用，初步推测太子参乙醇提取物对胞外多糖合成有调节作用。

关键词：灰树花；生物量；胞外多糖；太子参乙醇提取物

中图分类号：Q93-33      文献标识码：A      文章编号：1674-506X（2023）02-0028-0007

Preliminary Study on the Mechanism of Ethanol Extract of Pseudostellaria heterophylla on the Growth of Grifola frondosa and Exopolysaccharides

LI Fenglan¹，WU Tianxiang^1，2*，DENG Daixia¹，YUAN Dandan¹，JIANG Shoufa¹

（1.School of Liquor and Food Engineering, Guizhou University, Guiyang Guizhou 550025, China;

2.Guizhou Vocational College of Food Engineering, Guiyang Guizhou 551400, China）

Abstract: To investigate the mechanism of ethanol extract of Pseudostellaria heterophylla participating in the fermentation of Grifola frondosa and promoting the increase of extracellular polysaccharides. In this study, the effects of ethanol extract of Pseudostellaria heterophylla on biomass and extracellular polysaccharides of Grifola frondosa were studied. The changes of key enzyme activities of polysaccharide synthesis during the fermentation of Grifola frondosa were dynamically analyzed. At the same time, the effects of the addition of ethanol extract of Pseudostellaria heterophylla on mycelial growth and extracellular polysaccharide were discussed from the perspective of oxidative stress. The results showed that the biomass and extracellular polysaccharide content reached the peak（P＜0.01）when the addition amount of 85% ethanol extract of Pseudostellaria heterophylla was 9 g/L and fermentation for 7 days, which increased by 53.20% and 50.71% respectively compared with that without ethanol extract of Pseudostellaria heterophylla. The changes of key enzymes in polysaccharide synthesis of Grifola frondosa were dynamically analyzed. It was found that after adding 85% ethanol extract of Pseudostellaria heterophylla to the fermentation system of Grifola frondosa, the activities of phosphoglucomutase（PGM）, UDP glucose pyrophosphorylase （UDPG）and phosphoglucose isomerase（GPI）in Grifola frondosa reached the highest after 7 days’fermentation. Compared with the ethanol extract of Pseudostellaria heterophylla, the activities of PGM and UDPG increased by 9.44% and 18.57%, respectively, and the activity of GPI decreased by 19.46%（P＜0.05）. The levels of reactive oxygen species（ROS）, malondialdehyde（MDA）and hydrogen peroxide（H₂O₂）in the cells of Grifola frondosa were increased，and the activities of superoxide dismutase（SOD），glutathione peroxidase（GSH-P_x）and catalase（CAT）were enhanced. Compared to the ethanol extract without the addition of Pseudostellaria heterophylla，its content or enzyme activity were significantly increased （P＜0.05）. This study showed that the 85% ethanol extract of Pseudostellaria heterophylla promoted the increase of extracellular polysaccharides by regulating the activity of polysaccharide synthase when it was involved in the fermentation of Grifola frondosa. At the same time，the ethanol extract of Pseudostellaria heterophylla had a regulatory effect on the growth of Grifola frondosa.

Keywords：Grifola frondosa; biomass; extracellular polysaccharide; ethanol extract of Pseudostellaria heterophylla

doi：10.3969/j.issn.1674-506X.2023.02-004

收稿日期：2022-09-28

基金项目：国家自然科学基金地区科学基金项目（31460537）

作者简介：李凤兰（1997-），女，硕士研究生。研究方向：食品加工与安全。

*通信作者：吴天祥（1965-），男，博士，教授，研究生导师。研究方向：发酵工程与生物转化。

引用格式：李凤兰,吴天祥,邓代霞,等.太子参乙醇提取物对灰树花菌体生长及胞外多糖的影响机理初步研究[J].食品与发酵科技,2023,59(2):28-34.