Latest ArticlesA pure culture strain of a wild fungus from Zhouqu County of Gannan Tibetan Autonomous Prefecture in Gansu Province was obtained by tissue separation method. Morphological observation and ITS sequence analysis confirmed that the fungus was Trametes betulina, and its biological characteristics and domestication cultivation were studied. The results of biological characteristic investigation showed that the optimum carbon source was fructose, and the nitrogen source was yeast powder. The mycelia grew well under pH 6.0 and temperature of 32 ℃. The orthogonal test showed that the main factor affecting mycelial growth was temperature, and pH, nitrogen source and carbon source were secondary. The results of domestication cultivation experiments showed that the best spawn culture medium was: wheat grain 20%, sawdust 70%, bran coat 7%, gypsum 2%, lime 1%. The best expanded cultivation substrate formula was: wheat grain 25%, sawdust 25%, cottonseed hull 20%, corncob 20%, wheat bran 7%, sugar 1%, gypsum 1%, lime 1%. After inoculation, fruiting body could be harvested in 26 days under 25 ℃ condition. The total yield of fresh weight was 144.54 g/bag. The antioxidant activity of ultrasonic water extract of cultivated fruiting body increased with the increase of additional quantity of the extract. When the additional quantity of the extract was 5 mg/mL, the DPPH and hydroxyl radical scavenging rates were the highest, reaching 95.69% and 71.59%, respectively, while the ABTS+ scavenging rate peaked at 0.25 mg/mL, reaching 98.19%. The results provide a reference for the development and utilization of wild germplasm resource of Trametes betulina in China.
In order to explore the new application and mechanism of action of Cordyceps chanhua nucleoside extracts on solar dermatitis, the targets of C. chanhua nucleoside components treating solar dermatitis were screened by network pharmacology and molecular docking. The results of network pharmacology analysis were verified by mouse animal experiments. The results showed that thymine, adenine, N6-(2 hydroxyethyl) adenosine, inosine and adenosine were the main active nucleoside components of C. chanhua in the treatment of solar dermatitis, and TNF, IL1β, AKT1, IL6, INS, IFNG, EGFR, PTGS2, CTNNB1, and MAPK1 were the core targets of C. chanhua nucleoside components. Enrichment analysis showed that PI3K-Akt, TNF, MAPK and IL-17 signaling pathways were the major biomechanistic pathways of C. chanhua nucleoside components for the treatment of solar dermatitis. Molecular docking analysis showed that there was a strong binding affinity between the main active components of C. chanhua nucleoside components and the core targets. Animal experiments verified that dermal administration of C. chanhua increased collagen content and SOD antioxidant enzyme activity, and decreased PTGS2 content and levels of TNF-ɑ, IL-1β, and IL-17 inflammatory factors in mouse skin tissues. The results of Western blotting showed that C. chanhua nucleoside extracts inhibited the release of p38 MAPK and MMP9, and the molecular mechanism might be related to the MAPK signaling pathway. This study provides a new basis for the development of natural drugs against solar dermatitis.
Lentinula edodes polysaccharides exhibit diverse biological activities. Currently, most L. edodes polysaccharides are extracted from fruiting bodies, resulting in low yield, high cost, and short harvest period. Therefore, enhancing polysaccharide production has become a research priority. Epigenetic modifications regulate the synthesis and metabolism of secondary metabolites through various mechanisms and play significant roles in microbial secondary metabolism. To investigate whether polysaccharide synthesis in L. edodes is influenced by epigenetics, this study utilized L. edodes strain Xin 808 as experimental material, and analyzed the effects of different concentrations of two epigenetic modifiers [benzamide and sodium carboxymethyl cellulose (CMC-Na)] on mycelial growth, cellulase activity, polysaccharide production, activity of key polysaccharide-synthesizing enzymes, relative expression levels of the enzyme encoding genes, and antioxidant activity of polysaccharides. Results showed that although 4 µg/mL benzamid and CMC-Na reduced biomass compared to the control, they significantly promoted the growth of L. edodes mycelium on solid culture medium and increased the polysaccharide content in the mycelium. Cellulase activity decreased compared to that of the control, but the intracellular crude polysaccharide concentration increased, reaching 2.31-fold (benzamide) and 2.01-fold (CMC-Na) as compared with that of the control. The activities of UDP-glucose pyrophosphorylase (UGPase), phosphoglucose isomerase (PGI), and α-phosphoglucomutase (α-PGM), the enzymes associated with lentinan metabolism, increased. Under benzamide treatment, these enzymes exhibited increases in activity, increasing by 2.21-fold, 2.38-fold, and 2.19-fold as compared with enzyme activities of the control group, respectively. However, the relative expression levels of the encoding genes were significantly downregulated. In vitro polysaccharide antioxidant capacity increased in variant degrees. At the concentration of 0.2 mg/mL ·OH scavenging ability showed the most pronounced. These results demonstrate that adding benzamide and sodium carboxymethyl cellulose at appropriate concentrations influences L. edodes mycelial growth and polysaccharide synthesis.
Hericium erinaceus polysaccharides as the main active component extracted from H. erinaceus have many biological activities such as anti-oxidation, anti-tumor, and immune regulation. However, there are some limitations in solubility, bioavailability and activity intensity of natural H. erinaceus polysaccharides. In recent years, certain progress has been made in the studies of chemical modification, and structural features, having effects on the biological activities of H. erinaceus polysaccharides. In this paper, the recent advances in the study of chemical modification and biological activities of H. erinaceus polysaccharides are summarized, and the chemical modification methods of H. erinaceus polysaccharides through introducing new functional groups to substitute hydroxyl groups on the polysaccharide chains are elucidated. The changes in the structure and physicochemical properties of the chemically modified H erinaceus polysaccharides are introduced, and the alterations in biological activities and the underlying mechanisms of the chemically modified H. erinaceus polysaccharides are analyzed and discussed. It is expected that this work might provide a theoretical basis for further exploration of modification of H. erinaceus polysaccharides.
Physarum subgalbeum sp. nov. is described through observation of integrated morphological characterization and multigene phylogenetic analyses (nrSSU, mtSSU, α-Tub, and COI). The life cycle of P. subgalbeum was investigated in water agar medium and microscopic structure formation at different stages during sporulation was observed. This species is similar to P. galbeum in having golden yellow sporocarps. However, it differs in that its sporocarps often fuse into clusters, the spore surface is densely covered with small spines, and the lime nodes are elongated fusiform. Phylogenetic analysis results indicate that P. subgalbeum forms an independent monophyletic clade and constitutes a sister group relationship with P. galbeum. The spore germination of P. subgalbeum is split type, the plasmodial type is of phaneroplasmodium and sporulation requires approximately 10-12 hours, with lime nodes and capillitium forming prior to spore maturation. A comprehensive morphological description, including detailed micrographs, results of phylogenetic analyses, as well as a thorough account of its life cycle accompanied by corresponding microscopic images are provided.
Buchwaldoboletus xylophilus is the second cultivatable species of Boletales with significant scientific and commercial potential value. To better develop and utilize this wild resource, the morphological and molecular identification and the biological characteristic investigation of a wild strain, JSJ-Bx1, were carried out. The results show that this wild strain belongs to B. xylophilus. The hyphae grow well under the temperature of 35℃ and pH 4.0 on the medium using glucose as carbon source, and yeast extract as nitrogen source with the addition of inorganic salt FeSO4. The optimal medium formula consists of 20 g glucose, 2 g yeast extract, 1.5 g FeSO4, 0.3 g 1/2 MS medium, 20 g agar, and 1 L water. The hypha growth rate is 11.38 mm/d. The optimal expanded cultivation substrate formula consists of 20% sawdust, 30% cottonseed hulls, 20% wheat grains, 10% corn flour, 10% red soil, 8% bran, 1% gypsum powder, 1% glucose, 0.1% KH2SO4, and 0.1% FeSO4. The mycelial colonization period is about 20 days; primordial formation takes about 5 days, and the growth and maturation of the fruiting bodies takes about 7 days. The average yield is 96.64 g/bottle and the biological efficiency is 31.58%.
The study was designed to investigate the improvement effect and molecular mechanism of Sparassis latifolia polysaccharide (SLPs) on glucose metabolism in skeletal muscle of mice with glucose metabolism disorder induced by high-fat diet combined with streptozotocin (STZ). The results showed that SLPs intervention could significantly reduce the impaired glucose tolerance and insulin resistance and increase skeletal muscle glycogen content and improve the morphological damage of skeletal muscle caused by glucose metabolism disorder. Transcriptome analysis identified a total of 965 differentially expressed genes (DEGs). GO annotation and enrichment analysis showed that these genes were mainly involved in tissue development, animal organ morphogenesis, small molecule metabolism, myofibril, glycogen binding, and organic acid binding. The enrichment analysis of KEGG further revealed that DEGs were mainly enriched in PI3k/Akt signal pathway, AGE-RAGE signal pathway related to diabetic complications, insulin resistance, AMPK signal pathway and other signal pathways. In addition, SLPs could regulate the expression of genes and proteins related to AMPK/SIRT1/PGC-1α signal pathway and the activities of key enzymes in skeletal muscle of mice to improve glucose metabolism disorder in skeletal muscle, protect skeletal muscle damage, and maintain the metabolic homeostasis of the body. This study provides a theoretical basis for the development of SLPs as functional food ingredients.
The effects of temperature, pH, salt ions, and sugar solutions on the rheological properties of crude polysaccharide water extract (Naematelia sinensis polysaccharides-water extract, NAP-WE) from Naematelia sinensis were systematically investigated. Through static and dynamic rheological tests, changes in apparent viscosity, storage modulus (G′), and loss modulus (G″) of NAP-WE solutions under different conditions were analyzed. The results showed that NAP-WE exhibited shear-thinning behavior, and variations in temperature, salt ions, pH, and sugar solutions altered its apparent viscosity and gel characteristics. Within the 4-60 ℃ range, the apparent viscosity of 6.0% NAP-WE solution slightly decreased with rising temperature, and its weak-gel properties weakened in high-frequency regions, though it remained non-fluid. Acidic/alkaline environments reduced apparent viscosity and gel strength, but the consistency coefficient (k) and flow behavior index (n) showed minimal changes, confirming its stability within pH 3-9. Na+, K+, and Ca2+ all reduced viscosity and gel strength, with efficacy ranking Na+>Ca2+>K+; excessive Na+ over-shielded charges, altering polysaccharide chain aggregation and loosening the network structure. Glucose/sucrose solutions (4%-8%) decreased apparent viscosity, with sucrose exhibiting stronger effects. Low sugar concentrations (≤4%) minimally impacted gel properties, preserving weak-gel characteristics. In summary, NAP-WE’s rheological behavior is significantly regulated by environmental factors, and its weak-gel properties remain most stable under low temperature, neutral pH, low ion concentration, and low sugar content. The results provide a theoretical basis for applications of NAP-WE in food and pharmaceuticals.
Currently, research on regional genetic diversity and population genetic structure of Hericium erinaceus remains relatively scarce. Additionally, the analysis of the genetic background of germplasm resources has largely relied on fragmented molecular markers, lacking a comprehensive landscape of genome-wide variations, and thereby hindering the progress of genetic improvement. In this study, whole-genome resequencing of 35 H. erinaceus germplasm resources from Jilin Province was performed. Based on variation data such as single nucleotide polymorphisms (SNPs) and small insertions/deletions (InDels), their genetic structure, evolutionary relationships, and diversity characteristics were systematically analyzed. Population genetic structure analysis revealed that the optimal number of clusters was K=2, with significant genetic isolation between the cultivated strains and wild populations (Fst=0.079 8-0.090 4), indicating that artificial selection has led to a significant deviation in the genomic genetic background of the cultivated populations from wild populations. Genetic distance and linkage disequilibrium (LD) analyses showed low genetic differentiation among wild populations (Fst=0.022 5- 0.030 5) with an LD decay distance of 6-15 kb (r2<0.3), reflecting a coexistence pattern of geographical isolation and gene flow. Gene flow simulation confirmed weak gene flow to the cultivated strains only from the wild populations of Songshan Town and Changbai Mountain, with no genetic contribution from the wild populations of Huangsongdian Town and Manjiang Town. Principal component analysis (PCA) validated the geographical clustering of strains (the first three principal components explained 6.81%, 3.35%, and 3.31% of the genetic variation, respectively) and simultaneously revealed that artificial selection had led to abnormal genomic genetic characteristics in the cultivated strains. This study provides crucial genomic data support for the precise conservation and targeted genetic improvement of H. erinaceus germplasm resources. By deciphering genetic patterns, it aids in broadening the genetic basis of cultivated populations and promotes sustainable industrial development.
Wheat dwarf smut, caused by Tilletia controversa (TCK), is a dangerous fungal wheat disease that is highly destructive and difficult to eradication, possessing a significant impact. The disease is known as “No. 1 disease of wheat”, and is listed as a quarantine pest by European Plant Protection Organisation (EPPO), Australia, China and other countries/regions and organizations. Due to difficulties for distinguishing TCK from other closely related species such as Tilletia laevis in levels of morphological characteristics and molecular biology, misdiagnosis easily happen in quarantine inspections. In this study, TCK-specific molecular markers were developed at the genomic level, and four candidate genes, namely OG0008430, OG0008601, OG0008603 and OG0008610, were screened. Eight pairs of primers and four probes based on these four candidate genes were designed. Validation of combinations among the primers and probes were verified, and two sets of “triple + single” real-time fluorescence PCR methods were established. This combined method can effectively distinguish target species (TCK) from closely related species, achieving accurate identification of TCK, and it can also be used to distinguish different species within the genus Tilletia.