In our chemical investigation into Penicillium sp. UJNMF0740 derived from mangrove sediment, fourteen indole diterpene analogs, including four new ones, are purified by multiple chromatographic separation methods, with their structures being elucidated by the analyses of NMR, HR-ESIMS, and ECD data. The antibacterial and neuroprotective effects of these isolates were examined, and only compounds 6 and 9 exhibited weak antibacterial activity, while compounds 5, 8, and 10 showed protective effects against the injury of PC12 cells induced by 6-hydroxydopamine (6-OHDA). Additionally, compound 5 could suppress the apoptosis and production of reactive oxygen species (ROS) in 6-OHDA-stimulated PC12 cells as well as trigger the phosphorylation of PI3K and Akt. Taken together, our work enriches the structural diversity of indole diterpenes and hints that compounds of this skeleton can repress the 6-OHDA-induced apoptosis of PC12 cells via regulating the PI3K/Akt signaling pathway, which provides evidence for the future utilization of this fascinating class of molecules as potential neuroprotective agents.

Angucyclines/angucyclinones, a class of polyketides with diverse chemical structures, display various bioactivities including antibacterial or antifungal, anticancer, anti-neuroinflammatory, and anti-α-glucosidase activities. Marine and terrestrial microorganisms have made significant contributions to the discovery of bioactive angucyclines/angucyclinones. This review covers 283 bioactive angucyclines/angucyclinones discovered from 1965 to 2023, and the emphasis is on the biological origins, chemical structures, and biological activities of these interesting natural products.

The Qinghai-Tibet Plateau, known as “the third pole” of the Earth, boasts unique climatic conditions with abundant sunlight, low temperature, and significant annual temperature variations, nurturing a diverse array of soil microorganisms with rich metabolic products. In this study, 132 fungal isolates were isolated and identified from the soil samples collected in Nyingchi, Tibet, belonging to 32 genera and 59 species, while Ascomycota, Mucoromycota, and Basidiomycota accounted for 91.7%, 7.5%, and 0.8%, respectively. The evolutionary relationships among 59 representative strains were revealed by constructing a phylogenetic tree, while Penicillium, Fusarium, and Aspergillus were the most widespread fungal genera here, and the antibacterial activity of these strains was evaluated by the agar diffusion assay, leading to 27 active strains. Notably, six of them demonstrated significant activities against two or more tested bacteria. The antibacterial efficacy of the extracts of these six fungi, which were derived from four distinct media, was further evaluated at a concentration of 500 μg/mL. This study provides a valuable supplement to the investigations of cultivable soil fungi in Nyingchi, Tibet, laying a foundation for the development of soil fungi and antibacterial lead compounds in the area.