From Color to Cure: Bio-functional and Therapeutic Potential of Spirulina-Derived Natural Pigments

Abstract

Spirulina (Arthrospira spp.) produces natural pigments such as phycobiliproteins (notably phycocyanin), carotenoids (including β-carotene and zeaxanthin), and chlorophyll a, which are versatile biomolecules. These natural pigments exhibit a range of bioactivities, including antioxidant, anti-inflammatory, immunomodulatory, neuroprotective, hepatoprotective, anticancer, antimicrobial, and photoprotective effects, highlighting their potential in disease prevention and health promotion. This review provides a comprehensive and integrative synthesis of the chemistry, extraction, and stabilization of Spirulina pigments, along with findings from in vitro and in vivo studies that elucidate their mechanisms of action. Uniquely, it highlights recent advances in culture optimization, green extraction technologies, and formulation strategies for enhancing pigment stability and bioavailability. Furthermore, this review emphasizes the transition of Spirulina pigments from natural colorants to multifunctional bioactives with translational potential in the food, nutraceutical, cosmetic, and biomedical industries as natural colorants and as bioactive components. However, challenges persist regarding their stability, standardization, bioavailability, and clinical validation, which currently impede their practical applications. By identifying current gaps and proposing future research directions, this work establishes a novel framework for exploiting Spirulina pigments as sustainable aquatic biopharmaceutical resources poised to bridge nutrition, therapeutics, and biotechnology.