Wood-inhabiting fungi can decompose lignin, cellulose and hemicellulose, and play an integral role in the material cycle of forest ecosystems. In this study, a wood-inhabiting polypore collected from Yunnan Province, southwest China is introduced as a new genus typified by Porphyrostereum punctatum. The new genus Porphyrostereum is characterized by corticioid basidiomata with smooth, cream to slightly buff, cracked and becoming purplish pink or pinkish purple hymenial surface, a monomitic hyphal system and generative hyphae bearing clamp connections, and ellipsoid basidiospores. The phylogenetic analyses were performed with maximum likelihood and Bayesian inference methods based on ITS+nLSU nuclear RNA gene regions. Phylogenetic analyses showed that Porphyrostereum forms a monophyletic lineage within the order Polyporales in which it is closely related to Purpureocorticium.
A new lichen species from China, Physcia grumosa, is reported. The species is indentified by morph-anatomical and chemical analyses, and a phylogenetic tree based on rDNA-ITS sequences is constructed. Detailed descriptions and morphological illustrations are provided. P. grumosa is characterized by its grayish-white foliose thallus and lobes narrow and short; lobe tips with brown moderately dense cilia 2-4 mm long; upper surface with obvious white maculae, covered with numerous globular isidia; disc black, asci hyaline, 50-80 × 16.25-21.25 μm, 8-spored, asci tholus I+ yellow; brown ascospores 23.75-28 × 13.75-16.25 μm, 1-septate, Physica-type.
The genus Wallemia comprises a group of filamentous fungi known for their halophilic and xerophilic properties, allowing them to colonize low-water-activity habitats. Research on Wallemia species diversity in China remains limited, with only two species having been previously documented. This study aims at enhancing the understanding of Wallemia species diversity in China through isolating and identifying strains from diverse ecological regions. As a result, 62 strains were isolated from 12 provinces and six species, Wallemia canadensis, Wallemia hederae, Wallemia mellicola, Wallemia muriae, Wallemia sebi, and Wallemia tropicalis, were identified based on phylogenetic analysis. Among which the former four species were reported in China for the first time. The culture conditions of the representative strains of the four species (W. canadensis ZYJ2333, W. mellicola ZYJ2331, W. muriae ZYJ2345, and W. sebi ZYJ2323) were optimized using single-factor experiments combined with response surface methodology. The results demonstrated that the growth of the strains was optimal at 24.9 ℃, pH 5.2, and 5.8%-6.4% NaCl. The NaCl concentration exhibiting the most significant influence on fungal growth. In chaotropic tolerance assays, Wallemia strains maintained growth in solutions containing 3.5 mol/L MgSO4 or 1.4-1.8 mol/L MgCl2, highlighting their exceptional tolerance to ionic stress. Wallemia resources in China and efficient cultivation of the species have need of further research.
Protoplast fusion between high ergothioneine (EGT)-producing Ganoderma strains, Ganoderma resinaceum FQ23 and Ganoderma sessile FQ16 was performed, and 10 fusion strains (RS1, RS6, RS7, RS8, RS10, RS11, RS12, RS13, RS14, and RS16) were obtained. Substrate cultivation and solid fermentation of both fusion strains and parental stains were conducted. The key bioactive compounds including ergothioneine, triterpenoids and polysaccharides were quantitatively analyzed and systematically compared. Incorporating characteristic radar chart analysis, correlation matrix assessment, amino acid composition profiling, and nutritional value evaluation were carried out to obtain the strains suitable for substrate cultivation and solid fermentation. The results showed that fusion strains RS6 and RS8 were the most suitable for substrate cultivation. It was found that RS6 had the highest polyphenol content in the fruiting body, being 28.97% and 20.45% higher than that in the two parents FQ23 and FQ16, respectively; the EGT content is also higher, which is 3.05% and 4.02% higher than that in the two parents, respectively. RS16 was the most suitable for solid fermentation because the content of EGT was the highest in solid fermentation substrate, being 52.40% and 38.84% higher than that of the two parents FQ23 and FQ16, respectively; besides, the polysaccharide content has increased by 23.80% and 28.07%, respectively. The experimental findings demonstrated that our protoplast fusion breeding was successful and practicable for modulating the bioactive compounds in medicinal fungi.
Postharvest Cordyceps militaris has high moisture content, and fresh products are prone to mechanical damage and microbial infection. Therefore, the products in the market are mainly dry products and secondary processed products, and mainly stored at room temperature without vacuum sealing. In this study, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) were used to analyze the changes of main metabolites of dried C. militaris products stored at 4 ℃ for 1-6 months. In total, 856 non-volatile substances and 431 volatile substances were identified by metabonomics, among which 159 non-volatile substances and 110 volatile substances were screened by difference significance analyses. Further analysis showed that the non-volatile metabolites fluctuated significantly during three months of prestorage, and the components tended to be stable after three months of storage. The volatile components reached equilibrium after two months of storage. This study provides a new insight for exploring the eating time of dried C. militaris products.
Ganoderic acid, as one of the key active ingredients in Ganoderma lingzhi, holds significant development value in the fields of medicine and health care. Zinc finger proteins (ZFPs) constitute one of the largest transcription factor families in eukaryotic genomes. In which C2H2-type zinc finger proteins play crucial roles in regulating plant growth and development, and response to environmental stresses, and have proven to be effective in regulating the synthesis of secondary metabolites. In this study, the C2H2 transcription factor GlZF1 gene was successfully obtained from G. lingzhi through homologous sequence alignment, and its function was analyzed using RNA interference (RNAi) technology. The results demonstrated that the content of ganoderic acid in the GlZF1 RNAi transformants increased by an average of 26% compared with that in the wild-type strains. The expression levels of key enzyme genes in the ganoderic acid biosynthetic pathway, including 3-hydroxy-3-methylglutaryl-CoA synthase (hmgs), 3-hydroxy- 3-methylglutaryl coenzyme-A reductase (hmgr), farnesyl pyrophosphate synthase (fps), squalene synthase (sqs), and oxidosqualene cyclase (osc), were significantly upregulated in the RNAi transformants. In addition, the enzyme activity of peroxidase (POD) and the level of reactive oxygen species (ROS) increased significantly in the transformants. However, the enzyme activity of superoxide dismutase (SOD) and the content of proline decreased significantly in the transformants. The expression levels of antioxidant-related genes, such as catalase (CAT1, CAT2), glutathione peroxidase (GPx), and NADPH peroxidase (NoxR) gene generating reactive oxygen species increased significantly in the transformants. The results indicated that C2H2 transcription factor GlZF1 of G. lingzhi not only regulated the biosynthesis of ganoderic acids, but also had a significant effect on the antioxidant capacity in G. lingzhi. The results provide a preliminary basis for further understanding of the regulatory mechanism of the secondary metabolic pathway and the stress resistance mechanism against adverse environments of G. lingzhi.
The tyrosinase (TYR) gene family plays a crucial role in color formation and various physiological processes in fungi. In this study, a genome-wide identification and bioinformatics analysis of potential TYR genes in Stropharia rugosoannulata were conducted. Additionally, the relative expression levels of TYR family members at different developmental stages and in various parts of the fruiting bodies with different colors were investigated. In total, eight SrTYRs members were identified in the S. rugosoannulata genome. They were located on five chromosomes with a clustered distribution pattern. All eight genes contain numerous cis-element related to light-response and hormone-response in the upstream promoter regions. The SrTYRs exhibited differences in conserved motifs, signal peptides, subcellular localization, and physicochemical properties, yet shared similar three-dimensional structures. With the exception of SrTYR7, all members possess two highly conserved copper-binding sites. Phylogenetic tree analysis indicated that the SrTYRs could be divided into two classes. The expression levels of SrTYRs were low during the mycelial and primordial stages. However, SrTYR2, SrTYR5, SrTYR6, and SrTYR7 were highly expressed after the formation of fruiting bodies. Notably, SrTYR5, SrTYR6, and SrTYR7 showed significantly higher relative expression levels in the pileipellis compared to the cap, gills, and stipe, consistent with the observed sites of pigment accumulation, suggesting their potential function in color formation.
Anthracnose is the main disease in Camellia oleifera planting area, caused by Colletotrichum fructicola. As an important epigenetic modification, histone methylation plays an important role in the regulation of a variety of biological processes, which is currently unclear in C. fructicola. This study investigates the biological functions of the histone methyltransferase CfSet9 in C. fructicola and provides critical insights into the molecular mechanisms by which CfSet9 regulates pathogenicity. The ΔCfset9 mutant was generated via homologous recombination and PEG-mediated protoplast transformation, followed by the successful construction of the complemented strains ΔCfset9/CfSET9. The research found that CfSet9 was responsible for regulating the trimethylation of histone H4 lysine20 (H4K20me3). Biological phenotype determination indicates that the growth rate of the CfSET9 gene knockout mutant does not exhibit significant differences in comparison with the wild-type and complement strains, but its conidiation and appressorial formation rate were significantly reduced. The ΔCfset9 mutant was more sensitive to oxidation, osmotic pressure, and cell wall stress and more tolerant to DNA damage environment (MMS). The ΔCfset9 mutant exhibited significant reduction in pathogenicity. Taken together, our results revealed the critical roles of histone methyltransferase CfSet9 in conidiation, appressorial formation, appressorial turgor, external stress responses, and pathogenicity of C. fructicola.
Trichoderma strains possessing biological control functions have been used in agriculture against phytopathogens. Currently, only very few species of the genus were applied to or involved in plant disease control. Discovery of additional useful resources is desperately needed. In this study, biocontrol effect of Trichoderma vermifimicola strain TC467 was evaluated by dual confrontation culture, cellophane and two-compartment culture, pot experiments, and resistance to chemical fungicides. The results demonstrated that TC467 produced substances essential to phytopathogen control (including siderophore, xylanase and chitinase) and plant growth promoters (producing indole-3-acetic acid and gibberellin). The strain displayed a high inhibition rate against Botrytis cinerea reaching 85.26%; and its non-volatile and volatile secondary metabolites showed the inhibition rates to Sclerotinia sclerotiorum and B. cinerea as high as 84.67% and 47.62%, respectively. In pot experiments, comparing with untreated plants TC467 significantly enhanced the height and fresh weight of lettuce (Lactuca sativa var. ramosa) by 46.69% and 15.33%, respectively. Its fermentation broth effectively minimized the lettuce disease caused by B. cinerea with inhibition rate of 87.76%. In addition, the strain showed higher tolerance to hymexazol water-dispersible granule than that to other tested fungicides; at the concentration of 0.42 mg/L the growth rate of TC467 can even approach 98.19%. T. vermifimicola strain TC467 has the potential for practical application in biocontrol especially plant diseases caused by B. cinerea, which extends our knowledge of nature beneficial resources.
The symbiotic fungi secrete enzymes that degrade lignocellulose to help the larvae of the Sirex insect to gain food. In this study, the morphology, growth rate, and lignocellulose utilization capacity of the two symbiotic fungi Amylostereum areolatum and A. chailletii associated with Sirex nitobei, the major boring pest of coniferous trees, were studied, and the influence of the symbiotic fungi on the growth and development of the insect larvae was also investigated. The results showed that the growth rate of A. areolatum was slower than that of A. chailletii; the hyphae of the two fungi grown on the medium were all white, but A. areolatum turned the matrix yellow, and A. chailletii turned the matrix white. There was clamp connection in the two fungi; Hyphae of A. areolatum fragmented after a period of culture. A. chailletii degraded lignocellulose better than A. areolatum. Lignin peroxidase (LiP) of A. areolatum maintained high level on day 5 and 10, reaching a maximum level on day 10; the manganese peroxidase (MnP) reaches its maximum peak on day 5; the laccase (Lac) showed a trend of increase at the initial stage and decrease at later stage, and the enzyme activity was stable in the first 10 days, and reached its maximum on the 15th day. The LiP enzyme of A. chailletii reached its maximum activity on the 5th day, and then showed a downward trend reaching the lowest level on the 25th day; MnP enzyme had the highest activity on day 10 and then decreased. The enzyme activity of Lac peaked on day 20, and showed relatively stable in the early stage. The carboxymethylcellulase (CMCase) activity of the two fungi reached peak on day 5. Filter paper enzymes (FPase) activity trended to increase at the initial stage and decrease at the later stage, reaching its maximum on day 10 for A. areolatum, and on day 15 for A. chailletii. These results indicate that the two symbiotic fungi of S. nitobei have the ability to degrade lignocellulose, and the results probably provide a new idea for the control of S. nitobei by using symbiotic fungi.
To achieve highly sensitive quantitative analysis of aflatoxin B1 (AFB1) in grain products, the carbodiimide method was utilized to prepare an AFB1 complete antigen (AFB1-BSA), which was immobilized onto nanomagnetic beads. A biotin-labeled AFB1 monoclonal antibody was synthesized, and DNA amplicons containing multiple CRISPR/Cas12a system activation sequences were prepared. By optimizing reaction conditions, a novel CRISPR/Cas12a-based fluorescence immunosorbent assay (FLISA) for AFB1 detection was established, with subsequent evaluation of its sensitivity and stability. The results demonstrated that under optimal conditions, the detection limit (LOD) of this assay was 0.07 ng/mL, with a half-maximal inhibitory concentration (IC50) of 0.58 ng/mL and a quantitative detection range (IC20-IC80) of 0.12-2.90 ng/mL. The cross-reactivity rates with AFB1 structural analogs (AFG1, AFB2, AFG2, and AFM1) were 15.7%, 4.3%, 2.9%, and 8.1%, respectively, while negligible cross-reactivity was observed on other common mycotoxins, confirming the high specificity of this assay. Spike recovery experiments in maize and wheat samples yielded recoveries of 83.2%-112.5%, with coefficients of variation (CV) below 10%, demonstrating accuracy and stability of the assay. Quantitative detection of natural samples exhibited significant correlation with liquid chromatography-tandem mass spectrometry (LC-MS/MS) results (P<0.01), validating the method’s applicability for AFB1 analysis in real-world samples. This study provides a novel approach for the development of mycotoxin detection technologies in agricultural products.
The acquisition of homokaryotic strain and precise identification of mating types were the key factors limiting the breeding of new hybrid varieties of Agaricus bisporus. This study utilized resequencing data to develop and screen molecular markers, and constructed a dual identification technique for the mating type and parental origin of Agaricus bisporus W192 and A15. Based on the mating type identification results of single spore strains, hybrid pairing experiments were conducted. Based on the dual identification results, cultivation experiments and trait determination were carried out on the hybrid strains, and a new hybrid strain was successfully selected. Further, the mating type identification primer Mats2 (SNP site) and parental source identification primer QFi5 (InDel site) were screened and obtained. Among the single spore strains, homokaryotic strains of W192 accounted for 3.59% (5 A1 type and 10 A2 type), while those of A15 account for 4.72% (8 A3 type and 13 A4 type). 459 hybrid combinations were designed to obtain 1 251 strains. Through molecular marker double identification, 58 hybrid strains were obtained, all of which were paired from different mating types of strains. The success rate of hybridization between homokaryotic strains was 11.18%, and that between homokaryotic and heterokaryotic strains was 1.59%. In the cultivation experiment, 47 (81%) hybrid strains had normal fruiting ability, among which 21 (44.68%) strains had higher biological efficiency than their parents. This study aimed at using molecular marker to assist hybrid breeding technology for obtaining hybrid strains and improving the efficiency of hybrid breeding of Agaricus bisporus.
One strain (MLS 240528) of wild wood-decaying fungus from Bayi District, Linzhi City, Xizang was used as test material. Its taxonomic status was determined by morphological observations and homology comparison of ITS gene sequences and phylogenetic analysis. Single factor and orthogonal tests were adopted to study the growth potential of its mycelia on different stock medium with different carbon source, nitrogen source, inorganic salts, pH and temperature. The strain MLS 240528 was identified as Phellinus monticola. Orthogonal tests showed the influential factors on the mycelial growth rate of strain MLS 240528 were pH > inorganic salt > nitrogen source > carbon source. The optimal culture medium for the growth were soluble starch 20 g/L, peptone 2.5 g/L, magnesium sulphate 1.5 g/L, and pH 5.0. Suitable compost formula for enlarging production was 65% pine wood chips, 20% rice husk, 12% wheat bran, 1% sucrose, 1% gypsum, and 1% lime. Bagful mycelial colonization time was 40-63 d under room temperature of 10-20 ℃, air relative humidity of 70%-80%, natural ventilation, and scattered light irradiation. Primordia formed in 17-22 d.
In this study, the wild strains of Volvariella bombycina collected from the Qilian Mountains were used as the research object. Through morphological identification and ITS molecular phylogenetic analysis, it was identified as V. bombycina. The biological characteristics and artificial domestication and cultivation conditions were analyzed by using the isolated and purified strains as test materials. Through single factor analysis, it was found that the mycelia of V. bombycina showed the best growth state under the conditions of 28-30 ℃, pH 8.0 and C:N ratio of 40:1. Through orthogonal test, the optimum cultivation conditions were determined as follows: corn flour of 20 g/L, soybean flour of 5 g/L, carbon-nitrogen ratio of 40:1, pH 8.0, and growth temperature of 28 ℃. V. bombycina showed adaptable to a variety of media. The stock culture grows best on substrate containing 75% wheat. It can grow and develop normally on the substrate using sawdust, corncob and cottonseed hull as the main materials, and it can also develop normally on the substrate using corncob as the main material. Growth period from inoculation to fruiting body harvest was about 20-25 days, and the biological conversion rate reached 95%. The 15% mannitol was suitable for storage of the strain. This study provides reference for industrialization and market promotion of V. bombycina production.
A wild polypore strain was isolated from basidiomata collected in Jiangxi Province. On the basis of morphological characters and phylogenetic evidence of ITS sequence and LSU sequence, the strain was identified as Fomitopsis palustris. The effects of carbon source, nitrogen source, pH and temperature on the mycelial growth under solid culture conditions were investigated, and three optimal levels from the four single-factor experiments were selected for orthogonal experiments. Single-factor tests showed that the optimum carbon and nitrogen source, pH and temperature were sucrose and yeast extract powder, pH 4.0 and 35 ℃ respectively. The orthogonal tests indicated that using maltose as carbon source and yeast extract powder as nitrogen source, the mycelia grew well at pH 4.0 and temperature of 35 ℃. The effects of the four factors on the mycelial growth of F. palustris were ranked as temperature>nitrogen source>pH> carbon source. The appropriate cultivation spawn formula for F. palustris was 64% cottonseed hull, 20% sawdust, 15% wheat bran and 1% gypsum. Mycelial growth rate of sack-cultivation reached 0.60-0.67 cm/d. Mycelia were sackful after 15 d of cultivation at 35 ℃ in dark. Fruiting body matured after 20 d under the temperature of 23-32 ℃ and relative air humidity of 85%-90%.
Identification of macrofungal specimens collected from Pinus koraiensis forests in Wuying National Forest Park and adjacent forest farms was carried out based on morphological characteristics and two-locus (ITS-LSU) phylogenetic evidence. Six species are new to China: Amanita olivaceogrisea, Cortinarius vitiosus, Entoloma cornicolor, Inocybe carissima, Marasmius orientalis, and Pluteus eludens. Detailed morphological descriptions and illustrations for the species, with supplementary distribution and habitat information are provided. All specimens are deposited in the Northeast Asian Biodiversity Research Center, Northeast Forestry University.
Through germplasm resource collection, protoplast mononuclear hybridization, preliminary screening, plot cultivation comparison, regional trials, and two-year demonstration promotions across five locations, a novel Ganoderma lingzhi cultivar, ‘Xianzhi 5’, was successfully developed. This cultivar exhibits stable traits, high yield, and superior quality. It is characterized by dense, white villous mycelium with slightly fluffy, non-pigmented appearance. The optimal growth temperature for mycelia is 26-28 ℃, while the fruiting temperature ranges from 23 to 28 ℃. The fruiting bodies are kidney-shaped, semicircular, or nearly circular, featuring a reddish-brown surface with radial longitudinal ridges and ring patterns, and a light yellow underside. The stem is partial or central, displaying purple-brown, lacquer-like appearance. On average, the cap diameter is 225.9 mm, the thickness is 42.8 mm, and the stipe length is 111.1 mm. The cultivation period from planting to harvest is approximately 148 days. In multi-segment wood cultivation, ‘Xianzhi 5’ achieves an average absolute biological conversion rate of 3.57%, and the increase of production is 6.9% and 8.5% higher than that of the control cultivars ‘Xianzhi 1’ and ‘Hunong 1’, respectively. In regard to basidiospore powder production, the average absolute biological conversion rate is 3.62%, surpassing the production of ‘Xianzhi 1’ by 7.1% and ‘Hunong 1’ by 10.0%. The fruiting bodies contain 2.67% polysaccharides and 1.39% triterpenic acid, while the basidiospore powder contains 6.50% glycerol trioleate and 1.19% polysaccharides. During the demonstration and promotion phases, the yield of fruiting bodies and basidiospore powder, as well as the content of active components, remained stable. These results demonstrate that ‘Xianzhi 5’ is a cultivar with excellent comprehensive traits, making it a valuable addition to the field of medicinal mushroom cultivation.
