Enhanced production of lutein in Tetradesmus obliquus by medium engineering and its application for the development of lutein-loaded hydrogel

Commercial production of microalgae has been increasingly gained attention due to their high growth rates and production of value-added products. Among these, the lutein, a carotenoid, is highly significant because of its many uses in the food and medicine industries. As the global demand for lutein increases, its production through microalgae is an economically and environmentally sustainable approach. Its biosynthesis can be induced by a variety of stresses, including nitrogen and carbon. The lutein was extracted by solvent extraction and characterized via different techniques, viz., spectrophotometry, TLC, HPLC, and FTIR. As per the findings, Tetradesmus obliquus produced the maximum amount of lutein 5.40 mg/g in 0.0375 g/L nitrogen concentration which was further increased to 8.80 mg/g using 5 L/min of CO₂ flowrate. Additionally, the explanation of the increased lutein yield under various nitrogen and carbon treatments offers insightful information about the mechanism of lutein biosynthesis. The recovered lutein was ~ 84% pure with 80% antioxidant activity and was negative against Staphylococcus aureus. The carotenoid was further effectively utilized to create a lutein-infused hydrogel.