Microorganisms related to plant roots are vital for growth and health considered be the second genome of plant. When is attacked by pathogens, diversity community structure plant-associated microbes might changed. The goal this study characterize differences in root-associated endophytic actinobacterial composition antifungal activity between Fusarium wilt diseased healthy cucumber screen actinobacteria potential biological control cucumber. In present research, three plants (also termed...

Abstract The pyridine ring is a potent pharmacophore in alkaloid natural products. Nonetheless, its biosynthetic pathways are poorly understood. Rubrolones A and B tropolone products possessing unique tetra-substituted moiety. Here, we report the gene cluster propose pathway for rubrolones, identifying key intermediate that accumulates upon inactivation of sugar genes. Critically, this was converted to aglycones rubrolones by non-enzymatic condensation cyclization with either ammonia or...

The present study was conducted to examine the influence of a pathogen Sclerotinia sclerotiorum (Lib.) de Bary on actinobacterial community associated with soybean roots. A total 70 endophytic actinobacteria were isolated from surface-sterilized roots either healthy or diseased soybeans, and they distributed under 14 genera. Some rare genera, including Rhodococcus, Kribbella, Glycomyces, Saccharothrix, Streptosporangium Cellulosimicrobium, endemic samples, more diverse in samples compared...

In this study, the supernatant extract from fermentation broth of Streptomyces sp. NEAU-H3 showed strong antifungal activity against Fusarium graminearum strain PH-1 in vitro and vivo. Three known pyranonaphthoquinones were isolated by means an activity-guided method, frenolicin B was characterized as main active ingredient. Frenolicin displayed F. with EC50 value 0.51 mg/L, which is lower than that carbendazim (0.78 mg/L) but higher phenamacril (0.18 mg/L). could also strongly inhibit...

Abstract Angiotensin-converting enzyme inhibitors are widely used for treatment of hypertension and related diseases. Here, six karnamicins E 1 -E 6 ( – ), which bear fully substituted hydroxypyridine thiazole moieties characterized from the rare actinobacterium Lechevalieria rhizosphaerae NEAU-A2. Through a combination isotopic labeling, genome mining, enzymatic characterization studies, programmed assembly moiety in karnamicin is proposed to be due sequential operation hybrid polyketide...

Actinobacteria associated with insects represent one potentially rich source of novel natural products antifungal activity. Here, we investigated the phylogenetic diversity and community composition actinobacteria ants using a combination culture-dependent -independent methods. Further, assessed antagonistic activity against phytopathogenic fungi identified secondary metabolites from isolates bioactivity. A total 416 actinobacterial were obtained three ant species (Camponotus japonicus,...

The rhizosphere, an important battleground between beneficial microbes and pathogens, is usually considered to be a good source for isolation of antagonistic microorganisms. In this study, novel actinobacteria with broad-spectrum antifungal activity, designated strain NEAU-H2T, was isolated from the rhizosphere soil wheat (Triticum aestivum L.). 16S rRNA gene sequence similarity studies showed that NEAU-H2T belonged genus Streptomyces, high similarities Streptomyces rhizosphaerihabitans NBRC...

Astragalus membranaceus(A. membranaceus), a traditional tonic, contains flavonoids as one of its main bioactive components and key indicators for quality standard detection. These compounds predominantly exist in glycosylated forms after glycosylation modification within the plant. The catalytic products flavonoid glycosyltransferases A. membranaceus have been reported to be mostly monoglycosides, only AmUGT28 catalyzes luteolin form diglycosides. In this study, we cloned glycosyltransferase...

Seven new trialkyl-substituted benzene derivatives named benwamycins A–G (1–7), together with three known congeners, 8–10, were isolated from culture broth of the soil-derived Streptomyces sp. KIB-H1471. Their structures elucidated by using 1D and 2D NMR analyses in combination HRESIMS data. The absolute configurations 1–9 determined chemical conversion comparison circular dichroism spectra confirmed for 1 single-crystal X-ray crystallography. Compounds 6 7 have a unique γ-pyrone-like ring...

Two heterocycle-fused cytochalasan homodimers, bisaspochalasins D (1) and E (2), were isolated from an endophytic Aspergillus flavipes. Their chemical structures elucidated using a combination of HRESIMS, NMR, theoretical calculations, crystallographic techniques. Bisaspochalasin is dimerized by the first reported naturally occurring triple heterobridged 3,8-dioxa-6-azabicyclo[3.2.1]octane framework, while bisaspochalasin (2) employs pyrrole ring as linking moiety. Possible dimerization...

A novel actinomycete, designated strain NEAU-HEGS1-5T, was isolated from the ear of wheat (Triticum aestivum L.) and characterized using a polyphasic approach. The morphological chemotaxonomic characteristics coincided with those members genus Microbispora . results 16S rRNA gene sequence analysis showed that isolate most closely related to bryophytorum NEAU-TX2-2T (99.3 %), camponoti 2C-HV3T (99.2 amethystogenes JCM 3021T (99.1 %) rosea subsp. 3006T (98.5 %). However, two tree-making...

A novel actinomycete, designated strain NEAU-HRDPA2-9T, was isolated from the roots of wheat (Triticumaestivum L.) and characterized using a polyphasic approach. The morphological chemotaxonomic characteristics coincided with those members genus Microbispora. 16S rRNA gene sequence analysis showed that isolate most closely related to Microbispora bryophytorum NEAU-TX2-2T (98.6 %), hainanensis DSM 45428T (98.5 camponoti 2C-HV3T amethystogenes JCM 3021T (98.2 siamensis NBRC 104113T (98.1...

Rubrolones, isarubrolones, and rubterolones are recently isolated glycosylated tropolonids with notable biological activity.

During a screening for antifungal secondary metabolites, six new mono-/bis-alkenoic acid derivatives ( 2 – 7 ) and one known alkenoic derivative 1 were isolated from an endophytic fungi Scopulariopsis candelabrum . Their chemical structures identified by H-NMR, 13 C-NMR, 2D NMR, high-resolution mass spectrometry, as well comparisons with previously reported literatures. Among them, fusariumesters C‒F 5 are bis-alkenoic dimerized ester bond, while acetylfusaridioic A 6 fusaridioic D monomers....

Two novel Actinobacteria, designated strains NEAU-YY421T and NEAU-YY642T, were isolated from the rhizosphere soil of wheat (Triticum aestivum L.) collected Zhumadian, Henan Province, PR China characterized using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that NEAU-YY642T belonged to genus Streptomyces strain was most closely related fumanus CGMCC 4.1732T (97.9 % sequence similarity) naganishii DSM 40282T (97.8 %), zhaozhouensis LZS-5T (98.0 %) sedi...

Six new pimprinine alkaloids (1–6), including four dimers, dipimprinines A−D (1−4), and two monomers, (±)-Pimprinol D (5) pimprinone A (6), along with six known congeners (7–12), were isolated from a soil-derived actinomycete Streptomyces sp. NEAU C99. Structures of the compounds elucidated by extensive spectroscopic analyses, single-crystal X-ray diffractions, ECD calculations. Dipimprinines (1−4) showed weak cytotoxic activities against five tumor cell lines, HL-60, SMMC-7721, A-549, MCF-7...

Strepyrrolins A–E (1–5), five pyrrole–sesquiterpene hybrids were isolated from an endophytic Streptomyces . Isotope labeling experiments revealed that the pyrrole ring in strepyrrolins is constructed via a new logic nature.

Chemical investigation of a soil actinomycete strain <italic>Streptomyces gamaensis</italic> NEAU-Gz11 led to the isolation three alkaloids <bold>1–3</bold> with antiviral activity.

Abstract Flavin‐dependent enzymes enable a broad range of redox transformations and generally act as monofunctional stereoselective catalysts. Herein, we report the investigation multifunctional non‐stereoselective FMN‐dependent oxidoreductase RubE7 from rubrolone biosynthetic pathway. Our study outlines single RubE7‐catalysed sequential reduction three spatially distinct bonds in tropolone ring reversible double‐bond dehydrogenation. The crystal structure IstO (a homologue) with 2.0 Å...

Astragalus adsurgens, a significant forage plant cultivated in arid regions of northwest China, remains underexplored for its triterpenoid saponins and medicinal properties compared to the extensively studied membranaceus. To explore phytochemical profile A. adsurgens potential application medical field, we employed ultra-pressure liquid chromatography coupled with tandem mass spectrometry-based method identify cycloartane-type triterpenes. Eventually, five new triterpenoids, adsurgosides...

Abstract [isolation, structure elucidation, and biological activity]