The relative lack of marine venom could be attributed to the difficulty in dealing with venomous marine animals. Moreover, the venom of marine animals consists of various bioactive molecules, many of which are proteins with unique properties. In this study, we investigated the potential toxic proteins of jellyfish collected for ligand screening to understand the mechanism of the toxic effects of jellyfish. Since taxonomic identification is problematic due to the lack of proper keys, we conducted morphological and molecular mitochondrial DNA sequencing from COI and ITS regions. The venom extract from nematocysts found along the bell margins was used for protein characterization using SDS-gel electrophoresis and nano-liquid chromatography-tandem mass spectrometry. Ligand screening for the most potent toxin and antibacterial and cytotoxicity assays were carried out. The phylogenetic tree showed distinct clustering from other Catostylus sp. The proteomic analysis revealed venom with many bioactive proteins. Only 13 venom proteins were identified with molecular weights ranging from 4318 to 184,923 Da, exhibiting the venom’s complexity. The overall toxin protein composition of Catostylus sp. venom was dominated by potassium channel toxin alpha-KTx. Molecular docking of toxin alpha-KTx 1.13 revealed high specificity towards the human voltage-gated potassium channel Kv3 with a high fitness score and a minimum energy barrier of −17.9 kcal/mol. Disc diffusion and cytotoxicity assays revealed potent antibacterial activity against Klebsiella pneumoniae with no cytotoxicity. Further studies on detailed characterization and therapeutic potentials are warranted.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder requiring safer and more effective therapeutic alternatives. This study investigates a novel fucoxanthin derivative isolated from the marine brown alga Chnoospora minima using a comprehensive in silico approach. Molecular docking revealed that the derivative exhibited higher binding affinities toward α-amylase (–9.4 kcal/mol) and α-glucosidase (–8.0 kcal/mol) compared to the reference drug acarbose (–8.5 and –7.4 kcal/mol, respectively). Pharmacokinetic analysis predicted good intestinal absorption and P-gp inhibition (0.894) and moderate plasma clearance (7.864 mL/min/kg), while toxicity predictions classified it in toxicity class 3, with no respiratory or ocular toxicity. Drug-likeness evaluation showed only one Lipinski and one Veber rule violation, common for natural products. Molecular dynamics simulations conducted for 100 ns using NAMD 3.0 confirmed stable protein–ligand complexes with average RMSD values of ~1.3 Å and ~1.8 Å for α-amylase and α-glucosidase, respectively, and consistent hydrogen bonding profiles. Structural analysis identified a substitution of the allene bond with an unsaturated ketone at the C8′ position as a key contributor to enhanced enzyme interaction. The findings suggest that this fucoxanthin derivative is a promising natural candidate for T2DM therapy and warrants further investigation through lab experiments (in vitro and in vivo).