Sesquiterpenoids and furan derivatives from the Orychophragmus violaceus (L.) O.E. Schulz endophytic fungus Irpex lacteus OV38

Hypolipidemic sesquiterpenoids with diverse structural skeletons from the medicinal fungus Irpex lacteus

Nine previously undescribed azulenoid-type sesquiterpenoids, including four common (1-4), four 5/6-cleaved (5-8), and one rearranged (9), were isolated from the edible-medicinal fungi Irpex lacteus. The structures of the compounds were established by combining spectroscopic methods, including integrated NMR, MS, and UV, as well as quantum 13C NMR and ECD calculations. All compounds exhibited a meaningful reduction in triglycerides activity. Notably, compounds 3, 5, and 6 displayed significant hypolipidemic activity, with EC50 values of 43.8, 37.9, and 39.7 μmol/L, respectively. These values are comparable to the positive control, lovastatin, which exhibited an EC50 of 37.6 μmol/L.

Pyridine Derivatives and Furan Derivatives Identified From the Medicinal Mushroom Irpex lacteus SY1002

Three new pyridine derivatives, irpelactedines A-C (1-3), and a new furan derivative, irpelactedine D (5), along with two structurally related known compounds, irpexidine A (4) and 5-carboxy-2-furanpropanoic acid (6), were isolated from the medicinal fungus Irpex lacteus SY1002. Their structures were elucidated through nuclear magnetic resonance and mass spectral analyses, combined with density functional theory calculations of electronic circular dichroism data. Evaluation of angiotensin-converting enzyme (ACE) inhibitory activity revealed that compounds 1 and 3 displayed moderate inhibition, with IC50 values of 31.49 ± 3.41 and 80.96 ± 6.93 µg/mL, respectively. Molecular docking suggested that compound 1 is bound to the active site of ACE, leading to a reduction in its activity. Furthermore, cytotoxicity and antimicrobial activity tests revealed the low toxicity of these compounds. This is the first report on the ACE inhibitory activity of this class of pyridine derivatives, providing valuable insights into exploring the medicinal potential of I. lacteus and offering a structural template for developing new ACE inhibitors. Future efforts will focus on optimizing their structure and conducting in vivo testing to assess their therapeutic potential.

Genome Sequencing and Metabolic Potential Analysis of Irpex lacteus

Irpex lacteus is an edible and medicinal macrofungus with significant biological activity and broad pharmaceutical prospects that has received increasing attention in recent years. Although it is an important resource for macrofungi, knowledge of it remains limited. In this study, we sequenced, de novo assembled, and annotated the whole genome of I. lacteus using a PacBio Sequel II sequencer. The assembled 41.83 Mb genome contains 13,135 predicted protein-coding genes, 83.44% of which have searchable sequence similarity to other genes available in public databases. Using genome-based bioinformatics analysis, we identified 556 enzymes involved in carbohydrate metabolism and 103 cytochrome P450 proteins. Genome annotation revealed genes for key enzymes responsible for the biosynthesis of secondary metabolites, such as terpenoids and polyketides. Among them, we identified 14 terpene synthases, 8 NRPS-like enzymes, and 4 polyketide synthases (PKS), as well as 2 clusters of biosynthetic genes presumably related to terpene synthesis in I. lacteus. Gene family analysis revealed that the MYB transcription factor gene family plays an important role in the growth and development of I. lacteus. This study further enriches the genomic content of I. lacteus, provides genomic information for further research on the molecular mechanism of I. lacteus, and promotes the development of I. lacteus in the fields of drug research and functional food production.

Irpexols A-C, xanthone derivatives from the endophyte fungus Irpex laceratus A878

Three new xanthone derivatives irpexols A-C (1-3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1-3) share a de-aromatic and highly‑oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1-8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC50 values ranging from 24.83 to 45.46 μM, while the IC50 values of the positive control adriamycin was ranging from 1.11 to 1.44 μM.

New Sesquiterpenoids From Plant-Associated Irpex lacteus

Bacteria produce a large number of virulence factors through the quorum sensing (QS) mechanism. Inhibiting such QS system of the pathogens without disturbing their growth is a potential strategy to control multi-drug-resistant pathogens. To accomplish this, two new tremulane-type sesquiterpenoids, irpexolaceus H (1) and I (2), along with two known furan compounds, irpexlacte B (3) and C (4), were isolated from Orychophragmus violaceus (L.) OE Schulz endophytic fungus Irpex lacteus (Fr.) Fr. Their structures were elucidated by detailed spectroscopic data (NMR, HRESIMS, IR, and UV), single-crystal X-ray diffraction, and electronic circular dichroism (ECD) analysis. Furthermore, those compounds were evaluated for anti-quorum sensing (anti-QS) activity, and compound 3 was found contributing to the potential QS inhibitory activity.