Biosynthesized selenium nanoparticles (SeNPs) have attracted much attention because of their unique physical, chemical, and biological properties. The microbial reduction of selenium salts to SeNPs has great potential, while there is a lack of elite strains. In this study, we explored the reduction of Na₂SeO₃ by Streptomyces avermitilis into SeNPs. The colonies and hyphae of the strain and the synthesized SeNPs were characterized by optical microscopy, scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). At the same time, the inhibitory activity of SeNPs on Fusarium oxysporum, the main pathogen causing root rot of Lycium barbarum, was studied. The results showed that S. avermitilis converted Na₂SeO₃ into SeNPs and tolerated 300 mmol/L Na₂SeO₃, demonstrating strong tolerance. S. avermitilis synthesized spherical SeNPs in the cytoplasm, and most of SeNPs had a diameter of about 100 nm and were released by hyphal fracture. The SeNPs synthesized by S. avermitilis were amorphous, and their surfaces were dominated by C and Se, with the existence of O, N and other elements. SeNPs had functional groups such as -OH, C=O, C-N, and C-H, which were closely related to the stability and biological activity of SeNPs. The SeNPs synthesized by S. avermitilis showcased significant inhibitory activity on F. oxysporum, and 25.0 μmol/mL SeNPs showcased the inhibition rate of 77.61% and EC₅₀ of 0.556 μmol/mL. In conclusion, S. avermitilis can tolerate high Na₂SeO₃ stress and mediate the synthesis of SeNPs. The synthesized SeNPs have good stability and strong inhibitory activity, demonstrating the potential application value in the preparation of SeNPs and the control of L. barbarum root rot.
Streptomyces/metabolism* ; Fusarium/drug effects* ; Lycium/microbiology* ; Selenium/metabolism* ; Nanoparticles/chemistry* ; Plant Diseases/microbiology* ; Metal Nanoparticles/chemistry* ; Antifungal Agents/pharmacology*

Bacillus velezensis DJ1 exhibits broad-spectrum antagonistic activity against diverse phytopathogenic fungi, while its biocontrol mechanisms against Fusarium graminearum, the causal agent of maize stalk rot, remain poorly characterized. In this study, we integrated genomics and transcriptomics to elucidate the antifungal mechanisms of strain DJ1. The results demonstrated that DJ1 inhibited F. graminearum with the efficacy of 64.4%, while its polyketide crude extract achieved the control efficacy of 55% in pot experiments against this disease. Whole-genome sequencing revealed a single circular chromosome (3 929 792 bp, GC content of 47%) harboring 12 biosynthetic gene clusters for secondary metabolites, six of which encoded known antimicrobial compounds (macrolactin H, bacillaene, difficidin, surfactin, fengycin, and bacilysin). Transcriptomic analysis identified 243 differentially expressed genes (152 upregulated and 91 downregulated, P < 0.05), which were potentially associated with the antagonistic activity against F. graminearum. KEGG enrichment analysis highlighted activation (P < 0.05) of cysteine/methionine metabolism, pentose phosphate pathway, and polyketide biosynthesis pathways, indicating that DJ1 employed synergistic strategies involving antimicrobial compound synthesis, energy metabolism enhancement, and nutrient competition to suppress pathogens. This study provides a theoretical foundation for developing novel microbial resources and application technologies to combat phytopathogenic fungi.
Fusarium/drug effects* ; Bacillus/metabolism* ; Plant Diseases/prevention & control* ; Antifungal Agents/pharmacology* ; Genomics ; Zea mays/microbiology* ; Transcriptome ; Gene Expression Profiling ; Antibiosis ; Multigene Family ; Multiomics

Trichoderma spp. is a kind of filamentous fungi with important biocontrol value. Twelve strains of Trichoderma spp. were isolated from the soils of different types of crops in Shaoxing, Zhejiang and Foshan, Guangdong. The antagonistic resistance to Fusarium oxysporum was compared by plate confrontation test. The further analysis of volatile secondary metabolites for two strains were carried out using HS-SPME-GC-MS analysis. The results showed that T. asperellum ZJSX5003 and GDFS1009 had fast growth ability, and the inhibition effects on F. oxysporum were 73% and 74% respectively. Six identical volatile metabolites were detected as follows 2-Methyl-1-propanol, 3-Methyl-1-butanol, 3-Methyl-3-buten-1-ol, Acetyl methyl carbinol, Butane-2,3-diol and 6-n-pentyl-2H-pyran-2-one (6-PAP). Among them, 6-PAP was validated to have a higher inhibitory effect on F. oxysporum in vitro. This study will provide basis for the development of biocontrol agents with metabolites of Trichoderma, such as 6-PAP.
Antibiosis ; Antifungal Agents ; pharmacology ; Fusarium ; drug effects ; physiology ; Gas Chromatography-Mass Spectrometry ; Trichoderma ; chemistry ; metabolism

This study determined the effects of selenium on the growth of Fusarium strains and the effects of products extracted from the fungal cultures on relevant indicators of chondrocytes injury. The results showed that selenium supplementation resulted in differential effects on the mycelial growth of the strains. Levels of the chondrocyte injury indicators, including cell viability, proteoglycan and type II collagen contents and their mRNA expressions, were all reduced to varying degrees when the chondrocytes were incubated with fermentation extracts, the inhibitory effect varied depending on selenium content supplemented to fungal culture media. The results indicated that certain chain relations existed between the content of selenium in the environment, the production of some metabolites by fungi, and the occurrence of chondrocyte damage. The extent of this relationship and the role it plays in Kaschin-Beck disease pathogenesis merit further study.
Animals ; Cell Survival ; Cells, Cultured ; Chondrocytes ; pathology ; Fermentation ; Fusarium ; drug effects ; physiology ; Rabbits ; Selenium ; pharmacology

The present study was aimed to isolate the active compounds from the fermentation products of Fusarium oxysporum, which had hepatitis C virus (HCV) NS3 protease inhibitory activity. A bioactive compound was isolated by reverse-phase silica-gel column chromatography, silica-gel column chromatography, semi-preparative reverse-phase High Performance Liquid Chromatography (HPLC), and then its molecular structure was elucidated based on the spectrosopic analysis. As a result, the compound (H1-A, 1) Ergosta-5, 8 (14), 22-trien-7-one, 3-hydroxy-,(3β, 22E) was isolated and identified. To the best of our knowledge, this was the first report on the isolation of H1-A from microorganisms with the inhibitory activity of NS3 protease.
Enzyme Inhibitors ; chemistry ; isolation & purification ; metabolism ; Fusarium ; chemistry ; metabolism ; Hepacivirus ; drug effects ; enzymology ; genetics ; Hepatitis C ; virology ; Humans ; Magnetic Resonance Spectroscopy ; Viral Nonstructural Proteins ; antagonists & inhibitors ; metabolism

Ten compounds were isolated from the artificially induced dragon's blood of Dracaena cambodiana by various column chromatographies on silica and sephadex LH-20 gel. Based on spectral analysis of NMR and MS, their structures were identified as 3, 4-dihydroxyallylbenzene (1), 3', 4', 5'-trimethoxycinnamylalcohol (2), pinoresinol (3), (2R)-7, 4'-dihydroxy-8-methylflavane (4), (2R)-7,4'-dihydroxy-5-methoxy-8-methylflavane(5),(2S)-7,3'-dihydroxy-4'-methoxy-8-methylflavane(6) ,(2S)-4',7-dihydroxy-6, 8-dimethylflavane(7), 4,2',4'-trihydroxychalcone(8), 4,4'-dihydroxy-2-methoxydihydrochalcon(9) and Cambodianin E (10). Antibacterial activity assay showed that compounds 1, 4 and 10 have inhibitory effect on Fusarium oxysporum f. sp. cuben, Fusarium oxysporum f. sp. niveum, Fusarium oxysporum f. sp. vasinfectum and Ralstonia solanacearum.
Antifungal Agents ; chemistry ; isolation & purification ; pharmacology ; Dracaena ; chemistry ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; Fusarium ; drug effects ; Molecular Structure ; Plant Extracts ; chemistry ; isolation & purification ; pharmacology ; Spectrometry, Mass, Electrospray Ionization

The mycelium growth and sporulation in different temperature, pH value and light conditions were detected by using the crossing and haemocytometer method. The toxicity of five fungicides to Fusarium oxysporum was tested by mycelia growth method, so as to provide the reference for prevention and control against F. oxysporum. The optimum temperature and pH value of F. oxysporum to grow and spore were 28 degrees C and 6-7. Alternating light and darkness promoted growth and sporulation of bacterial colony. As for five fungicides, the EC50 of tebuconazole was 10.02 mg x L(-1), 92.50 times as much as carbendazim. The EC50 of myclobutanil and Fuxing was 91.23, 96.68 mg x L(-1), respectively. Tebuconazole showed the most tremendous inhibitory effect and control efficiency on F. oxysporum.
Fungicides, Industrial ; pharmacology ; Fusarium ; drug effects ; growth & development ; Mycelium ; drug effects ; growth & development ; Orchidaceae ; microbiology ; Plant Diseases ; microbiology ; Spores, Fungal ; drug effects ; growth & development

Twenty-four endophytic actinomycetes strains were isolated from the Salvia przewalskii in Tibetan Plateau of China by tablet coating method. Fusarium moniliforme, Helminthosporium turcicum and Bipolaris maydis were selected as indicator fungi to test the antimicrobial activities of these endophytic actinomycetes by tablet confrontation method. The results showed that 21 strains can produce antimicrobial substances which accounts for 85.7% of the total separates number. Four strains of endogenous actinomyces have more obvious antifungi activity. According to results of morphology and culture properties and 16S rDNA sequences of endophytic actinomyces, it is concluded that all of the isolates were streptomycetes trains.
Actinomyces ; chemistry ; genetics ; China ; DNA, Ribosomal ; genetics ; Fusarium ; drug effects ; Helminthosporium ; drug effects ; Salvia ; microbiology

OBJECTIVETo characterize, identify and investigate the anticancer properties of two new soil fungal isolates, Emericella nidulans and Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2 (ATCC) cell line.

METHODSSoil sample was cultured and two strains were chosen for morphological and phenotypical characterization. Partial sequences of the 18s rRNA gene and the internal transcribed spacer region ITS of the two isolates were amplified by PCR. Phylogenetic tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried out. In vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell line. Reverse transcription - PCR was carried out to detect level of expression of p53 in Caco-2 cell line.

RESULTSHF.1 displayed morphological and genotypic characteristics most similar to that of Fusarium solani while HF.2 was most similar to Emericella nidulans with high similarity of 99% and 97% respectively. The multiple sequence alignment of the two fungal isolates showed that, the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of 51st to 399th base pairs, 88th to 525th base pairs respectively. While those in the ITS genes were identified with the nucleotide regions of 88th to 463rd and 51st to 274th. The two isolates showed IC50 value with (6.24±5.21) and (9.84±0.36) µg/mL) concentrations respectively at 28h. Reverse transcription - PCR indicated that these cells showed high level of expression for p53 mRNA.

CONCLUSIONSThe morphology and molecular analysis identified HF.1 and HF.2 to be Fusarium solani and Emericella nidulans; new isolates of anticancer producing fungi from Wady El-Natroon city in Egypt. Treatment with the two isolates caused P53 expression in Caco-2 cell line. These two isolates can be used as an anticancer agents.

Antineoplastic Agents ; chemistry ; pharmacology ; Caco-2 Cells ; Complex Mixtures ; chemistry ; pharmacology ; Egypt ; Emericella ; chemistry ; classification ; genetics ; isolation & purification ; Fusarium ; chemistry ; classification ; genetics ; isolation & purification ; Gene Expression ; drug effects ; Humans ; Phylogeny ; Soil Microbiology ; Tumor Suppressor Protein p53 ; genetics ; metabolism

The rotten tuber of Pinellia ternata was found as an important disease during the growing season in Tianshui production area. The isolated pathogens were tested following Koch's postulates and identified as Fusarium oxysporum. The suitable growth conditions for the F. oxysporum were 15-30 degrees C, pH 6-8, the optimal condition was 21.9 degrees C and pH 7.2. Some fungicides were demonstrated to be effective to inhibit the pathogen growth. 70% thiophanate-methyl and 58% metalaxyl MZ were most effective to inhibit the pathogen. The EC50 were 0.002 7, 0.066 2 g x L(-1), respectively.
Dose-Response Relationship, Drug ; Fungicides, Industrial ; toxicity ; Fusarium ; drug effects ; isolation & purification ; Pinellia ; microbiology ; Plant Diseases ; microbiology ; Plant Tubers ; microbiology