Jellyfish bioactive compounds fueling marine biotechnology in blue economy and biomedicine

Jellyfish, often primarily perceived by the public as a marine nuisance, represent an increasingly valuable and sustainable source of diverse biomolecules with significant potential for the biomedical sciences, in addition to their crucial ecological role within marine ecosystems. This review explores the properties, extraction and applications of key jellyfish-derived compounds, including collagen, peptides, sulfated polysaccharides, glycoproteins and venom components. The relevance of jellyfish as a bioresource is underscored by episodic bloom events in the Mediterranean, where species such as Rhizostoma pulmo (Macri, 1778) have been reported in affected coastal areas. This review provides a critical synthesis of current advances in the extraction, characterization, and biotechnological exploitation of jellyfish-derived bioactive compounds, on ecologically and biotechnologically relevant Mediterranean species, which collectively represent accessible and high-impact targets for marine bioprospecting. Evidence from non-Mediterranean species is also discussed for comparative purposes to contextualize conserved biochemical features across different biogeographical regions. Among jellyfish-derived biomolecules, collagen emerges as the most technologically mature and translationally advanced compound, supported by reproducible extraction protocols, preserved triple-helical structure, cytocompatibility, and compatibility with pre-GMP manufacturing workflows. Recent studies further demonstrate that aquaculture-reared Cassiopea andromeda (Forsskål, 1775) may achieve collagen yields comparable to wild populations (~40–46%) while exhibiting enhanced antioxidant profiles, supporting the feasibility of controlled biofactory approaches. In contrast, peptides, sulfated polysaccharides, and venom components display promising biological activities but remain at earlier stages of technological readiness, requiring further standardization, structure–function elucidation, and regulatory development. Within circular and blue bioeconomy frameworks, jellyfish biomass—particularly from invasive or bloom-forming species such as C. andromeda—offers a concrete opportunity to unlock novel therapeutic solutions and advanced biomaterials, addressing critical unmet medical needs and offering a sustainable alternative to traditional biomedical resources.