Evaluating value-added biochemical and biodiesel production from Chlorococcum humicolo algal biomass in phycoremediation of textile dye effluents

[Display omitted] •Chlorococcum humicolo enhances phycoremediation and biodiesel production from dye effluents.•Growth and oil content varied in CFTRI media and dyeing effluents cultivation.•Combined dye effluent yielded 26 % of oil and 2.8 g/L biomass (DW).•Pilot tank effluent algae showed higher protein, β-carotene, lipids, and chlorophyll ‘a’.•GC–MS revealed 94% saturated fatty acids, ideal for biodiesel production. This study investigates the potentials of Chlorococcum humicolo algal biomass for the extraction of valuable biochemical and biodiesel production, with focus on the phycoremediation of textile dye effluents. The alga was cultivated in three media: CFTRI medium, combined dye effluent, and dye bath effluent in the laboratory. The highest cell count (254 × 104 cells/ml) and lowest oil content (16.6 %) were observed in CFTRI medium, while the combined dye effluent yielded the highest biomass (2.8 g/L dry weight (DW)) and oil content (26 %). Dye bath effluent produced intermediate results with 2.0 g/L DW biomass and 24 % oil content. Biochemical analysis revealed that algae grown in dye bath effluent from High Rate Algal Pond (HRAP) contained the highest levels of lipids (45.00 mg/106 cells), β-carotene (0.5683 µg/106 cells), proteins (9.89 mg/106 cells), and chlorophyll ‘a’ (0.9890 µg/106 cells). GC–MS analysis of the algal oil’s FAME profile showed a high proportion (up to 94 %) of saturated fatty acids, making it an excellent candidate for biodiesel production. Despite its better lipid content, C. humicolo demonstrates dual benefits for wastewater remediation and biofuel generation.