Shujing Sun

Basidiomycete fungi maintain a dikaryotic state throughout their life cycle, in which two genetically distinct haploid nuclei coexist within the same cytoplasm. However, the extent and functional significance of inter‐nuclear genomic divergence remain poorly understood. Here, we present the first telomere‐to‐telomere assemblies of two compatible monokaryons (D1 and D11) from a wild isolate of Pholiota adiposa , achieving 13 complete chromosomes with zero gaps and Benchmarking Universal Single‐Copy Orthologs completeness of 98.6% and 98.3%, substantially outperforming the previous fragmented assembly. The two nuclei exhibit only 75% collinear genes, with 570 (D1) and 668 (D11) strain‐specific genes. D1‐specific genes are enriched in energy metabolism, consistent with faster mycelial growth, while D11‐specific genes are enriched in genetic information processing and mitogen‐activated protein kinase signalling, revealing functional complementarity between the two haploid nuclei. Resequencing of 18 wild accessions identified two candidate regions associated with red pileus colour on chromosomes 6 and 12, the former as a major‐effect locus and the latter harbouring multiple pigment‐associated genes. Kyoto Encyclopedia of Genes and Genomes enrichment implicated phenylalanine metabolism, tyrosine metabolism, and terpenoid biosynthesis in colour formation, suggesting coordinated regulation across metabolic networks. This framework facilitates dissection of nuclear functional divergence and provides candidate targets for understanding fungal phenotypic variation.

Flammulina filiformis is one of the most important commercially cultivated species, and the assessment of strain quality is of paramount importance. The analysis measured physiological-biochemical indicators, morphological indicators, combined non-targeted metabolomics, and microbiomics in F. filiformis strains of different ages. The results indicate that, as the culture age increased, ergosterol content and catalase (CAT) activity declined continuously. The morphology of the mycelia gradually deteriorated, and yield continued to decrease. The relative content of lipids and lipid-like molecules decreased overall, while the proportion of organic acids and their derivatives increased; the oxidative phosphorylation pathway continued to be significantly enriched. The richness and diversity of the mycelium-associated bacterial community in the mycelia decreased significantly, and the microbial community structure changed. The community was dominated by the genus Acinetobacter from 15 to 60 days, whereas the genus Serratia was predominant in 90 days group. Correlation analysis revealed that the core differential signature metabolites MG 14:1_0:0_0:0, aspartic acid-threonine-aspartamide, and nicotinamide adenine dinucleotide (NAD⁺) were significantly correlated with multiple physiological-biochemical indicators. N-arachidonyl glycine showed significant correlations with 21 core bacterial genera; the dominant genera Acinetobacter and Serratia exhibited strong correlations with membrane homeostasis, core indicators of oxidative damage, and signature metabolites. These results indicate that the mycelial vitality of F. filiformis remains good within the first 15 days of cultivation, with significant ageing occurring after 60 days. These findings provide a theoretical basis for optimizing fungal strain preservation techniques and regulating mycelial ageing.

Cultivation substrate critically affects the quality of Tremella fuciformis. Five substrates, including cottonseed hulls (MZKs), Machilus pauhoi Kanehira sawdust (BNM), lotus seed hulls (LZKs), Corethrodendron scoparium sawdust (HB), and palm fiber (ZL), were evaluated for their effects on agronomic traits, nutritional composition, texture, and taste characteristics. Untargeted metabolomics was applied to elucidate substrate-associated metabolic variations, and polysaccharide monosaccharide composition was quantitatively analyzed. The results showed that the BNM group exhibited the highest fresh weight, whereas the LZK group presented the highest dry weight and crude polysaccharide content. The ZL group displayed the greatest ear piece thickness and fruiting body elevation. Higher protein contents were observed in the ZL and LZK groups, with no differences in crude fiber content. Texture analysis indicated that hardness was highest in the LZK group, whereas the MZK group showed better springiness, cohesiveness, and chewiness. Regarding taste characteristics, the MZK group exhibited the strongest sweetness, the LZK group showed a markedly higher bitterness, and umami levels were comparable across all groups. Metabolomic analysis revealed that substrate-induced variations in amino acids, saccharides, and taste-related metabolites were significantly associated with nutritional quality and taste attributes of T. fuciformis. Polysaccharides of fruiting bodies cultivated on the five substrates consisted of six monosaccharides, with composition ratios similar to those of spore extracellular polysaccharides; among them, differences in glucuronic acid (GlcA) proportion represented a key indicator distinguishing fruiting body polysaccharides from spore polysaccharides. This study revealed the metabolic basis and polysaccharide composition underlying substrate-dependent quality of T. fuciformis, supporting substrate optimization for high-quality production.

Liquid inoculum is widely adopted in the mushroom industry, yet preparing Tremella fuciformis liquid inoculum remains challenging due to its complex microbial community and dimorphic growth. This study aimed to establish a reliable protocol for T. fuciformis liquid inoculum and assess its practical application. Initially, liquefied spawn was produced by liquefying solid spawn. The application of standard liquefied spawn increased fruiting body yield by 8.2% (502.4 g/kg dry substrate) compared to solid spawn, but exhibited substantial batch-to-batch variation due to unstable microbial communities and low Tremellomycetes abundance. To address these limitations, liquid spawn was developed via pre-culture of pure T. fuciformis and Annulohypoxylon stygium mycelia. Cultivation tests demonstrated significantly enhanced performance with 608.2 g of fruiting bodies, which represented 11.1% improvement compared to solid spawn. Moreover, consistent yields could be observed across multiple batches. This stability was attributed to stable microbial community structure and the dominance of Tremellomycetes (abundance > 50%) in the fungal community. These results confirm the cultivation performance of T. fuciformis liquid spawn, highlighting its potential as an effective alternative to solid spawn for T. fuciformis industrial production.

A bioactive Pleurotus eryngii aqueous extract powder (SPAE) was obtained by spray drying and its performance in terms of physicochemical properties, in vitro digestion, inflammatory factors, and modulation of the intestinal microbiota was explored. The results indicated that the SPAE exhibited a more uniform particle size distribution than P. eryngii polysaccharide (PEP). Meanwhile, a typical absorption peak observed at 843 cm⁻¹ in the SPAE FTIR spectra indicated the existence of α-glycosidic bonds. SPAE exhibited higher antioxidant abilities and superior resistance to digestion in vitro. In addition, SPAE supplementation to mice significantly reduced the release of factors that promote inflammation, enhanced the secretion of anti-inflammatory factors, and sustained maximum production of short-chain fatty acids (SCFAs). Additionally, it significantly enhanced the relative abundance of SCFAs-producing Akkermansia and reduced the abundance of Ruminococcus and Clostridiides in intestines of mice. These results show the potential of SPAE as a novel material with prebiotic effects for the food and pharmaceutical industries.

Hypsizygus marmoreus has become one of the most popular edible mushrooms due to its high nutritional and economic value. Previous researchers found that Serratia odorifera could promote the growth of H. marmoreus by producing and secreting some of its inducers. However, the specific mechanism of action was still unclear. In this study, we found that the exogenous addition of sterile fermentation filtrate (HZSO-1), quorum sensing (QS) signaling molecules, 3-oxo-C₆-HSL, cyclo(Pro-Leu), and cyclo(Tyr-Leu) could significantly promote the growth of H. marmoreus, increase the number of clamp junctions, and the diameter of mycelium (p < 0.05). In addition, non-targeted metabolomic analysis revealed that 706 metabolites were detected in the treated group. Of these, 307 metabolites were significantly different (p < 0.05). Compared with the control, 54 and 86 metabolites were significantly increased and decreased in the HZSO-1 group, respectively (p < 0.05). We speculate that the sterile fermentation filtrate of S. odorifera could mediate the carbohydrate and amino acid metabolism of H. marmoreus by influencing the pentose phosphate pathway (PPP) to increase the energy supply for the growth and development of the mycelium. The above results will further reveal the growth-promoting mechanism of S. odorifera on H. marmoreus.