Bioenergy products sequestration proportions among three mixotrophically cultivated microalgae by remediating two organic waste resources.

Abstract\nNOVELTY STATEMENTIn this study, three microalgae species were cultivated using dairy and fish wastewater: <italic>Haematococcus pluvialis, Coelastrella saipanensis</italic>, and <italic>Chlorella</italic> sp. The process involved manipulating various physicochemical conditions, to determine optimal growth parameters. Our evaluation considered cell count, biomass productivity, specific growth rate, pigments, carbohydrates, proteins, lipid compositions, and cellulose stored in microalgae. A significant observation of highest cellulose accumulation was recorded in <italic>C. saipanensis</italic> cultivated in dairy waste (DW) medium (2.54 ± 0.042 µg/mg). In contrast, the species grown in fish waste (FW) media recorded a lower level (0.9405 ± 0.06 µg/mg) of cellulose. In DW, <italic>H. pluvialis</italic> and <italic>C. saipanensis</italic> accumulated substantial amounts of astaxanthin and carotenoid, respectively. Carbohydrate, protein, and lipid accumulation was maximized in DW culture, with <italic>H. pluvialis</italic> exhibiting a more incredible carbohydrate content. Lipid analysis showed as <italic> Chlorella</italic> sp. was capable of accumulating alpha-linolenic acid. The disparity may be attributed to DW’s nutritional and mineral content, which encourages cellulose deposition. The FTIR analysis confirmed the accumulation of cellulose. These findings underscore the potential of DW and FW media as valuable resources for microalgal biofuel and ethanol production, offering a hopeful future for sustainable energy production.The comparative analysis of microalgae cultivated in DW and FW water reveals distinct carbon sequestration patterns and bio-capture potential, observed from this study. In fact, this study identified <italic>C. saipanensis</italic>, which thrives exceptionally well in DW water and accumulate cellulose, a unique finding that pave the way on further research in this species on bioenery sequestration. By confirming the feasibility of bioproducts harvesting through compound analysis, this study highlights the potential of DW and FW as cheap nutrient resources for microalgae biomass generation, paving the way to bioremediation. [ABSTRACT FROM AUTHOR]