Predicting the Potential Distribution of Rubia cordifolia L.in China

[Objectives]We intend to conduct a study to predict habitat suitability and geographic distribution of Rubia cordifolia L.,to find the most suitable ecological environment for its growth,and to provide a theoretical basis for the development and cultivation of R.cordifolia L.industry.[Methods]Based on the environmental factors and the occurrence data,we predicted the potential geographic distribution of R.cordifolia L.in China by combining the MaxEnt model and ArcGIS.[Results]The training set and test set AUC were respectively 0.963 and 0.946,indicating that the MaxEnt model predicted well.The wettest monthly precipitation,precipitation in July,precipitation of driest season,and average monthly temperature in September and April were the dominant environmental factors affecting the distribution of R.cordifolia L.The highly habitable areas were mainly concentrated in central,eastern and northern China.[Conclusions]The results of this study can be used as a reference for the development of R.cordifolia L.industry in related areas.

Meroterpenoids with Potent Immunosuppressive Activity from Fungus Bipolaris zeicola

Six new meroterpe no ids,bipolarinoids A-F(1-6),and two known congen ers(7-8)were isolated from a soil-derived fungus Bipolaris zeicola.Their structures were elucidated based on extensive spectroscopic techniques(ineluding HRESIMS and ID and 2D NMR data),and the absolute configurations of 1-4 were further confirmed viasingle-crystal X-ray diffraction an alysis and comparis on of experimental electronic circular dichroism(ECD)data.Structurally,compound 1 represents the first case of cochlioquinone derivatives featuring a formaldehyde group at C-11, and compou nd 3 features a rareamino group at C-11.In the immunosuppressive activity assay,compounds 5-8 showed potent inhibitory activity against concanavalin A(ConA)-induced T lymphocyte proliferation with IC50 values of 78.3,81.1,48.3,and 48.0 nmol/L,respectively,which provided promising leads for designing and developing new im-muno suppressive agents to treat auto-immunological diseases.

Distachydrimanes A-F,phenylspirodrimane dimers and hybrids with cytotoxic activity from the coral-derived fungus Stachybotrys chartarum

By integrating one strain-many compounds(OSMAC)and LC-MS-based molecular networking strategies,distachydrimanes A-F(1-6),six novel phenylspirodrimane dimers and hybrids representing two types of unprecedented terpenoid-polyketide hybrid skeletons,were isolated from the modified fermented rice substrate of a coral-derived fungus Stachybotrys chartarum.All the structures incorporating their absolute configurations were elucidated based on comprehensive spectroscopic analyses,mainly including HRESIMS and NMR data,single-crystal X-ray diffraction(Cu Kα),and comparison of the experimental electronic circular dichroism(ECD)data.Architecturally,compounds 1-6 represent an unprecedented class of dimeric phenylspirodrimanes with an unexpected C-18-C-23′linkage,of which compounds 1-3 also feature an unexpected 5-methyl-1,3-benzenediol moiety via a carbon-carbon linkage.The bioactivity assay demonstrated that compounds 1,5 and 6 induced cell proliferation inhibition,G0/G1 cell cycle arrest,senescence and mitochondrial-mediated apoptosis in L1210 cells,highlighting their potentials as a new category of anticancer agents.