PDF(Pubmed)
Abstract：
Aspergillus cristatus is a crucial edible fungus used in tea fermentation. In the industrial fermentation process, the fungus experiences a low to high osmotic pressure environment. To explore the law of material metabolism changes during osmotic pressure changes, NaCl was used here to construct different osmotic pressure environments. Liquid chromatography-mass spectrometry (LC-MS) combined with multivariate analysis was performed to analyze the distribution and composition of A. cristatus under different salt concentrations. At the same time, the in vitro antioxidant activity was evaluated. The LC-MS metabolomics analysis revealed significant differences between three A. cristatus mycelium samples grown on media with and without NaCl concentrations of 8% and 18%. The contents of gibberellin A3, A124, and prostaglandin A2 related to mycelial growth and those of arabitol and fructose-1,6-diphosphate related to osmotic pressure regulation were significantly reduced at high NaCl concentrations. The biosynthesis of energy-related pantothenol and pantothenic acid and antagonism-related fluvastatin, aflatoxin, and alternariol significantly increased at high NaCl concentrations. Several antioxidant capacities of A. cristatus mycelia were directly related to osmotic pressure and exhibited a significant downward trend with an increase in environmental osmotic pressure. The aforementioned results indicate that A. cristatus adapts to changes in salt concentration by adjusting their metabolite synthesis. At the same time, a unique set of strategies was developed to cope with high salt stress, including growth restriction, osmotic pressure balance, oxidative stress response, antioxidant defense, and survival competition.
摘要：
曲霉菌是用于茶叶发酵的重要食用菌。在工业发酵过程中，真菌经历了低到高渗透压的环境。探讨渗透压变化过程中物质代谢变化规律,这里使用NaCl来构建不同的渗透压环境。采用液相色谱-质谱联用(LC-MS)结合多变量分析,分析了不同盐浓度下A.cristatus的分布和组成。同时,体外抗氧化活性进行了评价。LC-MS代谢组学分析揭示了在具有和不具有8%和18%的NaCl浓度的培养基上生长的三个A.cristatus菌丝体样品之间的显著差异。在高NaCl浓度下，与菌丝体生长有关的赤霉素A3，A124和前列腺素A2的含量以及与渗透压调节有关的阿拉伯糖醇和1,6-二磷酸果糖的含量显着降低。能量相关的泛醇和泛酸的生物合成和拮抗相关的氟伐他汀，黄曲霉毒素,在高NaCl浓度下，交替霉素显着增加。A.cristatus菌丝体的几种抗氧化能力与渗透压直接相关，并随着环境渗透压的增加而呈显着下降趋势。上述结果表明A.cristatus通过调节其代谢物合成来适应盐浓度的变化。同时,开发了一套独特的策略来应对高盐压力，包括增长限制，渗透压平衡，氧化应激反应，抗氧化防御，生存竞争。
