Enhancing 3-O-methylfunicone production by endophytic Talaromyces pinophilus J6 through culture optimization and its anti-Helicobacter pylori activity

Endophytic Paenibacillus lactis PEL6 from Mitrephora heyneana as a Source of Anti-Staphylococcus aureus Metabolites: In Vitro and In Silico Evaluation

Overall, this study identifies P. lactis PEL6 as a promising endophytic source of anti-S.

Orsellinic Acid from the Endophytic Fusarium oxysporum Drives Specialized Metabolism in Peperomia obtusifolia

The metabolic cooperation between plants and their endophytic fungi represents a promising frontier in the biosynthesis of natural products. This study elucidates the contribution of the endophytic fungus Fusarium oxysporum Po18 to the production of aromatic polyketides that drive specialized metabolism in Peperomia obtusifolia. Cultivation parameters for F. oxysporum were optimized using a Central Composite Rotatable Design (CCRD), revealing that mild temperatures (28 °C) and extended incubation (9 days) maximized orsellinic acid accumulation. LC–MS/MS identified orsellinic acid as [M–H]– at m/z 167.0356, with the diagnostic fragment ion m/z 122.8924, and quantified by HPLC–DAD, achieving a concentration of 132 μg/mL under optimized conditions. Comparative metabolomic analysis and molecular networking (GNPS) revealed related fungal metabolites, including lecanoric acid, 6-methylsalicylic acid, and citrinin, all derived from the fungal polyketide synthase (PKS) pathway. These metabolites are proposed to act as biosynthetic precursors for chroman and benzopyran derivatives previously reported in P. obtusifolia. The results provide the first experimental evidence of a biosynthetic partnership between Fusarium and Peperomia, in which the endophyte may supply aromatic scaffolds that could subsequently undergo downstream modifications in the host plant. This study expands the understanding of fungal–plant metabolic interactions and highlights F. oxysporum as a sustainable biotechnological source of aromatic polyketides with potential applications in natural product chemistry and biocatalysis.

Isolation and Characterization of Multifunctional Seed-Borne Endophytic Bacterium Lysinibacillus sphaericus YEBEVIA for Enhancing Maize Growth

The endosphere biology attracts increasing interest from researchers seeking to understand plant-microbe synergism and the bio-efficacy of microbial inoculants in enhancing plant growth and soil health. This study was designed to isolate and identify a novel seed-borne endophytic Lysinibacillus sphaericus YEBEVIA with plant growth-promoting capabilities and bioinoculation potential. Morphological assessment revealed that isolate D3 was a Gram-positive, rod-shaped bacterium with a large cell size and undulated colony margins. All the isolates fermented glucose, fructose, sucrose, and maltose, producing only acid from lactose. PGP screening demonstrated that all isolates exhibited beneficial traits, although at varying intensities. Lysinibacillus sphaericus YEBEVIA displayed remarkable zinc-solubilizing ability (3.0 cm), siderophore production (2.5 cm), and high HCN activity (2.87 µg/mL). Phosphate solubilization (17.46 µg/mL) and IAA production (14.26 µg/mL) were also notably high in L. sphaericus YEBEVIA. Heavy-metal tolerance assays revealed that L. sphaericus YEBEVIA responded positively to increasing concentrations of zinc and lead, with the highest growth observed at 2 g supplementation. Enhanced tolerance to chromium was also recorded, whereas cadmium showed no significant effect compared with the control. Minimum inhibitory concentration (MIC) effects were observed only with lead sulphate, producing inhibitory zones of 5.1 cm, 2.5 cm, and 6.8 cm. Bioinoculation studies showed significant improvements in maize growth. Under field conditions, inoculated plants developed 13 leaves, 41 roots, and a fresh weight of 256.9 g, while greenhouse trials produced comparable enhancements. These findings highlight the strong potential of L. sphaericus YEBEVIA as a biofertilizer for sustainable crop improvement.

Isolation of the new polyketide (−)-R-talaropinophiloic acid guided by an integrated metabolomics-dereplication approach

As part of our ongoing bioprospecting program targeting endophytic fungi, the strain Talaromyces pinophilus J6 was isolated from Euphorbia umbellata. The endophyte metabolic potential was evaluated through a combined metabolomics-dereplication workflow based on an in-house high-resolution mass spectrometry (HRMS) database of Talaromyces metabolites. The strategy enabled rapid annotation of seven metabolites (a-g), allowing rapid characterization of the fungal metabolome and guiding the isolation of potentially new specialized metabolites. Chromatographic fractionation of the crude extract from T. pinophilus J6 cultivated on potato dextrose agar supplemented with ammonium sulfate afforded two polyketides: the new (-)-R-talaropinophiloic acid (1) and the known 3-O-methylfunicone (2). Their chemical structures were determined by Nuclear Magnetic Resonance (NMR), Circular Dichroism (CD), and HRMS analyses. The cytotoxic activities were assessed against the muscle-invasive bladder cancer cell line T24 by MTT assay, yielding IC₅₀ values of 204.70 µM for 1 and 59.68 µM for 2, compared with 6.4 µM for the positive control cisplatin. Assays against the non-tumor RPE-1 cell line showed that 2 displayed a CC₅₀ of 16.62 µM, whereas 1 was non-toxic, highlighting 1 as highly selective for cancer cells. Overall, our results expand knowledge of the chemical diversity of the Talaromyces genus and underscore its potential as a promising source of new bioactive polyketides. A metabolomics–dereplication approach applied to Talaromyces pinophilus J6 from Euphorbia umbellata led to the isolation of 3-O-methylfunicone and the new (–)-R-talaropinophiloic acid with selective cytotoxic activity against T24 cancer cells. A metabolomics–dereplication approach applied to Talaromyces pinophilus J6 from Euphorbia umbellata led to the isolation of 3-O-methylfunicone and the new (–)-R-talaropinophiloic acid with selective cytotoxic activity against T24 cancer cells.

Morpho-molecular approach reveals a myco-endophyte, Aspergillus novoparasiticus CBS126849 (MTCC-13997) from the roots of Capparis decidua with therapeutic and enzymatic potential

Isolation and Characterization of Endophytic bacteria from Wedelia chinensis with Potent Biocontrol and Plant Growth-Promoting Activities

Endophytic bacteria represent a promising, sustainable alternative to synthetic agrochemicals for plant disease management by actively antagonizing phytopathogens and stimulating host immune responses. Despite its traditional use as an antimicrobial remedy, Wedelia chinensis remains underexplored as a source of beneficial endophytes. This study aimed to isolate and screen endophytic bacteria from W. chinensis for their antifungal activity against Fusarium oxysporum. Among 14 endophytic isolates, Bacillus subtilis LS1-5 showed the strongest antifungal activity by dual culture assay. Its cell-free culture filtrate effectively inhibited fungal spore germination by 91.3% at a 20% concentration. Crucially, B. subtilis LS1-5 produced several extracellular enzymes, including cellulase, amylase, chitinase, pectinase, gelatinase, lipase, and protease. Furthermore, the LS1-5 strain exhibited a broad array of plant growth-promoting and environmental resilience traits. Notably, it synthesized indole-3-acetic acid (IAA) at 2.11 ± 0.27 µg/mL in an LB medium without L-tryptophan, significantly promoted a 34.19% increase in root elongation, and demonstrated remarkable tolerance to extreme conditions, including high salinity (11% NaCl) and broad pH levels ranging from 6 to 12. Additionally, volatile organic compounds (VOCs) emitted by LS1-5 significantly inhibited the severe bacterial pathogens Xanthomonas oryzae (45.83%) and Xanthomonas citri (47.99%). These findings highlight B. subtilis LS1-5 as a highly effective candidate for biological control and sustainable agricultural applications.