Comparative analysis of nutritional composition and bioactive properties of Chlorella vulgaris and Arthrospira platensis: Implications for functional foods and dietary supplements

The rising incidence of chronic diseases has spurred interest in functional foods rich in antioxidants and essential nutrients, as well as in exploring their potential cytotoxic activity against cancer cells. This study aims to address this gap by providing a comprehensive comparison of their biochemical composition and bioactive properties, offering insights into their targeted applications in functional foods and supplements. This study investigated the nutritional composition and bioactive properties of two algae species, chlorella (Chlorella vulgaris) and spirulina (Arthrospira platensis). Analysis included total protein content, amino acid profiles, mineral compositions, fatty acid profiles, B vitamin contents, polyphenol profiles, carotenoid contents, antioxidant activities (DPPH˙ and ABTS+ assays), and cytotoxic activities. Chlorella exhibited higher protein content (64.63%) compared to spirulina (58.24%). Spirulina showed higher concentrations of non-essential and essential amino acids, except for methionine. Mineral analysis revealed spirulina’s superiority in calcium, potassium, sodium, iron, manganese, and zinc, whereas chlorella contained higher copper and lead levels. Fatty acid analysis indicated chlorella’s dominance in saturated fatty acids, while spirulina showed higher proportions of monounsaturated and polyunsaturated fatty acids. Polyphenol analysis highlighted chlorella’s higher levels of p-hydroxybenzoic acid, whereas spirulina contained more rutin and catechin. Chlorella also exhibited higher levels of niacin and riboflavin compared to spirulina. Additionally, spirulina extracts, whether ethanolic or hexane-based, demonstrate substantial antioxidant effects, as evidenced by their lower IC50 values in both DPPH˙ and ABTS+ assays relative to chlorella. Overall, spirulina showed superior antioxidant effect. Chlorella hexane extract showed slightly higher cytotoxic potential compared to spirulina. These findings enhance our understanding of the nutritional and health-promoting properties of chlorella and spirulina, suggesting their potential applications in functional foods and dietary supplements. While in vitro assays indicate promising bioactivity, future studies should include in vivo experiments to confirm the health benefits and functional applications of these microalgae.