Four new cyclic pentapeptides, avellanins D–G (1–4), together with four known compounds (5–8), were isolated from a mangrove-derived Aspergillus fumigatus GXIMD 03099 fungus from Acanthus ilicifolius L. Their structures were elucidated by analysis of HRESIMS, NMR, and ESI-MS/MS data. Their absolute configurations were determined by X-ray diffraction analysis and Marfey’s method. Compounds 1–8 were screened for insecticidal and antibacterial activities. Compound 2 showed insecticidal activity against newly hatched larvae of Culex quinquefasciatus with an LC50 value of 86.6 µM; compound 4 had weak activity against Vibrio harveyi with an MIC value of 5.85 µM.
Gallic acid (GA) and its derivatives are anti-inflammatory agents and are reported to have potent effects on Osteoarthritis (OA) treatment. Nonetheless, it is generally accepted that the therapeutic effect and biocompatibility of GA is much weaker than its esters due to the high hydrophilicity. The therapeutic effect of GA on OA could be improved if certain structural modifications were made to increase its hydrophobicity. In this study, a novel sulfonamido-based gallate was synthesized by bonding sulfonamide with GA, and its biological evaluations on OA were investigated. Results show that 5-[4-(Pyrimidin-2-ylsulfamoylphenyl)]-carbamoyl-benzene-1,2,3-triyl triacetate (HAMDC) was able to reverse the effects induced by Interleukin-1 (IL-1) stimulation, and it also had a great effect on chondro-protection via promoting cell proliferation and maintaining the phenotype of articular chondrocytes, as well as enhancing synthesis of cartilage specific markers such as aggrecan, collagen II and Sox9. Furthermore, a docking study showed that HAMDC fits into the core of the active site of a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), which provides an explanation for its activity and selectivity.
LC-HRMS/MS molecular networking enabled the targeted isolation of three new neoantimycin analogs (1, 3, 5) and two known ones (2, 4) from the culture broth of Streptomyces conglobatus RJ8.
Five previously undescribed peptaibiotics, including one 7-mer lipopeptaibol named lipotrichaibol A (1), and four 11-mer peptaibiotics named trichoderpeptides A-D (2–5) were isolated from the rice culture medium of the sponge-derived fungus Trichoderma sp. GXIMD 01001. Their structures and absolute configurations were unambiguously established by extensive spectroscopic data analysis and advanced Marfey’s method. All isolated compounds were evaluated via CCK8 bioassays to investigate their antiproliferative activity. Only compound 1 exerted potent cytotoxicity against HT-29 and DLD-1 cells with IC50 values at 10.3 ± 1.9 and 12.31 ± 1.5 μM, respectively. In further in vitro bioassay, compound 1 exhibited significant inhibition in colony formation assay, induced apoptosis and blocked the cell cycle in the G0/G1 phase. The mechanism may be related to the regulation of the Erk1/2 signaling pathway.