In this study, fresh Lyophyllum decastes was dried using hot air drying (HAD), hot air combined with vacuum drying (HAVD), and vacuum freeze drying (VFD). Additionally, the quality and volatile compounds were analyzed. VFD achieved the best color retention, the highest rehydration capacity, and the slightest damaged tissue structure; however, it recorded the longest drying time and the highest energy consumption. HAD was the most energy-efficient of the three methods. Furthermore, the products with more hardness and elasticity were obtained by HAD and HAVD—this finding was convenient for transportation. In addition, GC-IMS demonstrated that the flavor components had significantly changed after drying. A total of 57 volatile flavor compounds was identified, and the aldehyde, alcohol, and ketone compounds were the primary ingredient of the L. decastes flavor component, whereby the relative content of the HAD sample was apparently higher than HAVD and VFD. Taken together, VFD was better at preserving the color and shape of fresh L. decastes, but HAD was more appropriate for drying L. decastes because of the lower energy consumption, and was more economical. Meanwhile, HAD could be used to produce a more intense aroma.

The composition of culture substrate is an important environmental factor that affects the growth and metabolism of Hypsizygus marmoreus, and sawdust is commonly used as the substrate for cultivating mushrooms. However, the influences of sawdust on metabolic level of H. marmoreus in mycelial growth is little reported. In this study, the effect of sawdust addition on mycelial growth rate, morphological characteristics and nutrient content of H. marmoreus was explored, and the metabolic response was analyzed based on LC-MS/MS. The results showed the mycelial growth rates and the number of mycelial clamp connections in sawdust medium A and sawdust medium B were significantly higher than that of the basic medium (Control). The mycelial morphology in sawdust medium A was denser, with higher edge trimness and stronger aerial mycelia. The contents of crude fiber, crude protein and polysaccharide of the mycelia from sawdust medium A increased by 85.15%, 90.65% and 92.61%, respectively, compared to that in the basic medium. A total of 551 metabolites were identified and obtained. The differential accumulated metabolites (DAMs) were mainly amino acids, lipids compounds and carbohydrates. It was speculated that the addition of sawdust played a vital role in promoting the cell division and, thus, the formation of clamp connections in H. marmoreus mycelia. Regarding amino acids, the metabolism of glycine, serine and ABC transporters was active with the increase in sawdust, thereby increasing the protein content. And some valuable bioactive molecules were found, such as docosahexaenoic acid (DHA). This study will lay the foundation for further research on the substance transformation and quality improvement of cultivation substrate for mushrooms.

DNA methylation, a cornerstone of epigenetic regulation, governs critical biological processes including transcriptional modulation, genomic imprinting, and transposon suppression through chromatin architecture remodeling. Recent advances have revealed that aberrant methylation patterns—characterized by spatial-temporal dysregulation and stochastic molecular noise—serve as key drivers of diverse pathological conditions, from oncogenesis to neurodegenerative disorders. However, the field faces dual challenges: (1) current understanding remains fragmented due to the inherent spatiotemporal heterogeneity of methylation landscapes across tissues and developmental stages, and (2) mechanistic insights into non-canonical methylation pathways (particularly 6mA) in non-mammalian systems are conspicuously underdeveloped. This review systematically synthesizes the evolutionary-conserved versus species-specific features of 5-methylcytosine (5mC) and N6-methyladenine (6mA) regulatory networks across three biological kingdoms. Through comparative analysis of methylation/demethylation enzymatic cascades (DNMTs/TETs in mammals, CMTs/ROS1 in plants, and DIM-2/DNMTA in fungi), we propose a unified framework for targeting methylation-associated diseases through precision epigenome editing, while identifying critical knowledge gaps in fungal methylome engineering that demand urgent investigation.

Tremella fuciformis is a dimorphic fungus that can undertake a reversible transition between yeast-like conidia and hyphal forms. The transformation mechanism and proteomic differences between these two forms have not been reported. Therefore, in this study, we attempted to explore the differential protein profiles of dikaryotic yeast-like conidia from fruiting bodies and mycelia (FBMds) and dikaryotic mycelia (DM) by synthetically applying high-resolution MS1-based quantitative data-independent acquisition (HRMS1-DIA) full proteomics and parallel reaction monitoring (PRM) targeted proteomics. The results showed that a total of 5687 proteins were quantified, and 2220 of them (39.01%) showed more than a two-fold change in expression. The functional analysis of the differentially expressed proteins (DEPs) confirmed that the DEPs were mainly located in the membrane and nucleus. The FBMds tended to express proteins involved in biosynthesis, metabolism, DNA replication and transcription, and DNA damage repair. At the same time, DM exhibited an increased expression of proteins involved in signal transduction mechanisms such as the mitogen-activated protein kinase (MAPK) signaling pathway and the Ras signaling pathway. Further, phosphorylation analysis confirmed the importance of the MAPK signaling pathway in T. fuciformis dimorphism, and comparative metabolism analysis demonstrated the metabolic difference between FBMds and DM. The information obtained in the present study will provide new insights into the difference between FBMds and DM and lay a foundation for further research on the dimorphism formation mechanism of T. fuciformis.

Tremella fuciformis Berk., also known as white fungus and snow fungus, is one of the important edible and medicinal mushrooms in China. The quality characteristics and metabolites of different T. fuciformis varieties directly affect the stability of their processed products. In this study, two new varieties of Tremella fuciformis, namely ’TYH-SD1’ (yellow) and ’TWH-SD2’ (white), which were obtained by the team through single-spore crossbreeding and its control varieties Tr21 (yellow) and Tr01 (white), were used as test materials. The characteristics and nutritional quality of the four varieties of substrates were comparatively analyzed, while metabolomics was employed to investigate the differences in flavor substances. The results demonstrate that TYH-SD1 and TWH-SD2 had a higher rehydration rate and faster rehydration speed compared with the control strains Tr21 and Tr01, with a smaller stem and higher yield. Notably, TWH-SD2 had a 29.06% increase in its rehydration rate and it had higher contents of crude polysaccharide and vitamin D₃. The surface of TYH-SD1 ear pieces exhibited a porous structure with a larger pore size and the surface of TWH-SD2 ear pieces displayed a surface characterized by connected gully-like protrusions and fewer indentations, which were significantly different from that of Tr21 and Tr01 ear pieces. The textural analysis shows that TYH-SD1 and TWH-SD2 ear pieces were softer and more elastic, with greater cohesion and recovery, indicating that they had high tensile and deformation recovery ability. Metabolomics analysis revealed that the relative content of aldehydes in the volatile flavor substances TYH-SD1 and TWH-SD2 was high in n-alpha-aldehyde, nonanaldehyde, and n-pentanal. The relative content of alkanes in TYH-SD1 was second only to that of aldehydes, with decane having the highest content, contributing to its more almond aroma, fruity aroma, and fat aroma. TWH-SD2 exhibited the highest concentration of alcohols, accounting for 43.57%, which may result in a clear, mushroom, and lipid odor. The above results will provide theoretical basis for the further production, processing, and application of the new varieties.