Repetitive isolation of known compounds remains a major challenge in natural-product-based drug discovery. LC-MS/MS-based molecular networking has become a highly efficient strategy for the discovery of new natural products from complex mixtures. Herein, we report a molecular networking-guided isolation procedure, which resulted in the discovery of seven new cyclopentapeptides, namely, pseudoviridinutans A−F (1−7), from the marine-derived fungus Aspergillus pseudoviridinutans TW58-5. Compounds 1−7 feature a rare amino acid moiety, O,β-dimethyltyrosine, observed for the first time from a marine-derived fungus. The planar structures of 1−7 were elucidated by detailed analyses of IR, UV, HR ESI-Q-TOF MS, and 1D and 2D NMR spectroscopic data. Meanwhile, their absolute configurations were determined through a combination of Marfey's method and X-ray diffraction. Subsequent bioassay revealed the antiinflammation potential of 1−7, especially 6, which inhibited the production of nitric oxide (NO), a vital inflammatory mediator, in LPS-induced murine macrophage RAW264.7 cells by regulating the expression level of NLRP3 and iNOS.

Two new citrinin dimers bearing a 6,6-spiroketal moiety (1 and 2) and four known analogues (3–6), together with 18 known citrinin monomers (7–24), were isolated from the culture of hydrothermal vent-associated fungus Penicillium citrinum Y34. Their structures were identified by extensive spectroscopic analyses, 13C NMR calculation in combination with DP4+, linear correlation coefficient (R2), and mean absolute error (MAE) values analyses, and electronic circular dichroism (ECD) calculation. The α-glucosidase and ATP-citrate lyase (ACL) inhibitory activities of isolated compounds were evaluated. Compounds 1, 3, and 12 displayed moderate α-glucosidase inhibitory activities with IC50 values of 239.8, 176.2, and 424.4 μM, respectively. Enzyme kinetics investigations of 1 and 3 suggested their non-competitive inhibition of α-glucosidase with Ki values of 204.3 and 212.7 μM, respectively. Meanwhile, compound 4 showed significant ACL inhibitory potential with an IC50 value of 17.4 μM. Furthermore, the interactions of 1, 3, and 12 with α-glucosidase and 4 with ACL were investigated by molecular docking assay. This study demonstrates that citrinins, especially for their dimers, could be potential lead compounds for the development of new agents for the treatment of metabolic diseases.

Twin-row ridge cultivation is widely used in soybean planting in northern China. In order to find the optimal parameters of soybean agronomy, the twin-row planter with subsoiling was designed. Field experiments were conducted to evaluate the effects of plant arrangements and cluster densities on soybean growth and grain yield under different tillage treatments. The experiment used a randomised complete block design consisting of 20 treatments in a 2×2×5 factorial arrangement. Two tillage treatments were inter-row subsoiling and no subsoiling. Each tillage treatment included the combination of plant arrangements (side-by-side arrangement and triangular arrangement) and cluster densities (one, two, three, four, and five plants). The variables measured included soil moisture content, seedling emergence, biomass accumulation and allocation, and grain yield. We have concluded that the performance of inter-row subsoiling treatment was much better than that of no subsoiling treatment. Meanwhile, the triangular arrangement and two plants per cluster were the best choices for soybean biomass accumulation and grain yield in northern China. This study provided a reference for the innovative design of the twin-row planter with subsoiling and the optimisation of soybean agronomy.