Marine Drugs

Eight previously unreported cembranoids (1–8), along with four known ones (9–12), have been isolated and identified from the soft coral Lobophytum crissum collected from the South China Sea under the guidance of HSQC-based DeepSAT analysis for targeted isolation. The structures of the new compounds were determined by comprehensive spectroscopic analysis, QM-NMR, TDDFT-ECD calculations, and comparison with reported literature data from analogs. In in vitro bioassays, all the isolated compounds have been screened for their antibacterial and antiproliferative activities.

Chitosan (CS) has emerged as a versatile biopolymer for designing drug delivery systems (DDS) in colorectal cancer (CRC) therapy due to its biocompatibility, mucoadhesive properties, and ability to be surface-functionalized. This scoping review systematically analyzed current experimental studies on CS-based DDS for CRC, comparing non-targeted formulations with ligand-modified systems to identify advances in targeting efficiency, drug release behavior, and biological outcomes. Among the twenty-five initially identified studies, divided into two categories, non-targeted CS-based DDSs and ligand-modified CS-DDSs, five fulfilled the inclusion criteria for ligand-functionalized systems. These incorporated targeting moieties, such as folic acid (FA), hyaluronic acid (HA), and galactose (Gal), to achieve receptor-mediated uptake via FRα, CD44, and ASGP receptors, respectively. Ligand modification consistently enhanced cellular uptake, reduced IC₅₀ values, and improved tumor-selective cytotoxicity compared to non-targeted systems. However, in vivo validation remains scarce, with only one study confirming tumor accumulation in xenograft models. Moreover, no clinical trials currently assess CS-based nanocarriers for the treatment of CRC. Overall, CS represents a promising modular platform for targeted nanomedicine, but translational progress requires bridging preclinical success with comprehensive in vivo and clinical evaluation.

Reliable taxonomy of biological producers is essential for finding new natural substances. A recent study morphologically re-examined 21 accessed vouchers to confirm multiple reported misidentifications and suggested marine sponges from the genus Rhabdastrella as the only known source of the isomalabaricane triterpenoids. The present study aimed to find isomalabaricane-containing sponges among the samples collected during seven marine expeditions to the Vietnam waters of the South China Sea, accompanied with their identification confirmed using morphological and molecular (18S rRNA and 28S rRNA) analyses. As a result, nine sponges identified as Rhabdastrella globostellata were found to contain isomalabaricanes in their extracts. A chemical investigation of the R. globostellata (PIBOC O63-136) specimen led to the isolation of nine isomalabaricane triterpenoids including the new compound 1, of which the chemical structure was elucidated based on HRESIMS and NMR data. Subsequently, a combination of LC–MS/MS, multivariate statistical analysis, and feature-based molecular networking was applied to detect, annotate, and characterize the isomalabaricane chemical diversity across the nine R. globostellata specimens. As a result, two primary chemotypes containing individual sets of annotated compounds were discovered within the Vietnamese population of this sponge. Moreover, obtained data showed a series of new extremely rare isomalabaricanes in R. globostellata extracts including nitrogen-containing metabolites and glycosides of this structural class.