Exploration of microalgae for novel functional food ingredients through isolation, cultivation, and metabolite enhancement

Microalgae have been explored as a remarkable and vast natural source of unique health-promoting foods ingredients. Because of the continuously increasing demand for functional foods, it is essential to identify new, suitable ingredients for use in the food industry. The aim of this research is to isolate and optimize the cultivation conditions of microalgae and cyanobacteria from diverse aquatic environments to enhance the yield of valuable bioactive compounds for use as food additives. Thirty samples were collected from various water sources, including dams, rivers, lakes, the sea, and the Lonar lake which is one of the rare basaltic meteorite impact craters in the world. A total of nine strains were isolated, including four strains of Chlorella, two of Chlorococcum, and one each of Geitlerima, Scenedesmus and Arthrospira. The selected strains were further studied for cultivation under different conditions (such as autotrophic, mixotrophic, autotrophic using LEDs, and mixotrophic using LEDs) and for the extraction of metabolites like phycocyanin and β-carotene. The highest protein yield (47.9%) and lipid content (4.20%) were observed in Arthrospira sp. The results show that Arthrospira sp. contains sufficient biomass, protein, and lipids to be a valuable resource. As a tropical country, India boasts a rich diversity of cyanobacterial resources with significant potential for commercial exploration in natural product development.