The textile industry is a growing sector worldwide and has immense opportunity in terms of providing employment and boosting a nation’s economy. However, there exist severe environmental risks associated with textile effluents that impact the surrounding ecosystem. This review offers an approach for sustainable water management using phycoremediation to treat dye-laden wastewater and recover bio-based pigments from the residual biomass. Microalgae such as Chlorella, Scenedesmus, Phormidium, and macroalgae like Sargassum, Enteromorpha, and Codium has been extensively used in several phycoremediation-based studies, and their residual biomass could be a potent source for extraction of bio-based pigments. This review also recommends studies involving the algal-bacterial consortia approach for treating dye-laden wastewater as an alternative to conventional, biobased methods. The outcome of this study will provide policymakers and researchers with new insight to manage water and wastewater resources sustainably. Furthermore, this review also enhances our understanding of nature-based decontamination approaches for treating dye-laden wastewater through algal-based technologies.

Biological remediation of dye-rich textile effluents remains challenging, as these compounds exert toxic, mutagenic, and carcinogenic impacts on humans and aquatic organisms. To address this, a polyurethane foam (PUF) integrated anaerobic bioreactor was designed and subsequently scaled up to facilitate textile effluent decolourization and detoxification. The lab-scale bioreactor optimized with 24% (w/v) PUF packing rate exhibited superior performance over suspended growth bioreactors, achieving 85.2 ± 9.5% color and ~ 73% turbidity removal within 72 h. Furthermore, successful scale-up to a 200 L pilot-scale bioreactor operated continuously for 71 days under real industrial conditions validated the system’s robustness, sustaining color and COD removal efficiencies of 76 ± 6.7% and 71.9 ± 4.5%, respectively. Scanning electron microscopy (SEM) confirmed dense microbial biofilm formation on PUF after 28 days, indicating effective surface colonization and biomass retention. Toxicity assessment of treated samples from pilot-scale bioreactor showed substantial detoxification, with Lemna minor growth inhibition reducing from 98–100% in untreated effluent to 65–70% in treated samples. Likewise, seed germination assay showed an improvement in growth germination index (GGI%) from 3–5% (in untreated samples) to 75%, 58%, and 20% for treated samples using Vigna radiata, Cicer arietinum, and Lactuca sativa seeds, respectively, which reasonably confirmed the detoxification of treated effluent. Overall, the PUF integrated anaerobic bioreactor exhibited promising decolourization, COD removal, and toxicity reduction. However, incorporation of further aerobic polishing unit can remove residual COD and toxicity to a greater extent. Graphical abstract