Biochemical Profiling and Bioactivity of Five Selected Microalgae Species as Potential Sources of Bioactive Compounds for Nutritional and Biotechnological Applications

Microalgae have emerged as promising sustainable sources of bioactive compounds, essential for addressing global challenges. This study investigated the biochemical profiles of five microalgae species: Nannochloropsis sp., Tetraselmis chuii, Chaetoceros muelleri, Thalassiosira weissflogii, and Tisochrysis lutea. By using NMR spectroscopy, organic acids, amino acids, and other compounds were revealed. T. chuii was particularly rich in acetate, whereas the main organic acid in T. lutea was lactate. ICP-MS analysis indicated substantial variations in elemental concentrations across the species, with T. chuii showing the highest calcium content and C. muelleri having the highest iron content. SPME-GC/MS revealed that alcohols, acids, and aldehydes were the principal volatiles. Fatty acid profile was described by GC-MS technique. Carotenoid profiling highlighted T. lutea as having the highest total carotenoid content. Antioxidant activities were evaluated with C. muelleri demonstrating superior efficacy. Furthermore, the microalgae demonstrated moderate to significant activity against both bacterial and fungal pathogens. In addition, T. lutea and Nannochloropsis sp. demonstrate significant antibiofilm activity against various bacterial strains. This study highlights the potential of these microalgae as valuable sources of diverse metabolites contributing to nutritional and biotechnological advancements and addressing global food and health challenges.