Microalgal competence in urban wastewater management: phycoremediation and lipid production

Cyanobacterial phycoremediation: a sustainable approach to dairy wastewater management

The dairy industry is a significant sector within the food industries, known for its high-water consumption and consequent generation of dairy wastewater (DWW), which is rich in pollutants like Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD). Improper disposal of DWW poses serious environmental challenges, including eutrophication and highlighting the need for sustainable biological treatment methods. This study investigates the potential of indigenous cyanobacterial strains Oscillatoria pseudogeminata, Oscillatoria proteus, Oscillatoria trichoides, and Lyngbya ceylanica for the bioremediation of DWW. Under controlled laboratory conditions, these strains were assessed for their uptake capabilities for 15 days. Results indicated that L. ceylanica significantly reduced (approx. 70%, P < .05) in key pollutants such as ammonia, nitrate, and phosphate compared to other strains. Biochemical analyses indicated a decrease in biomass, chlorophyll a, carotenoids, proteins, and carbohydrates in DWW relative to the growth of cyanobacteria in BG 11 media. This decline may hinder the effectiveness of cyanobacterial in wastewater remediation. The findings highlight the efficacy of selected cyanobacteria in nutrient removal from DWW, emphasizing their dual role in nutrient uptake through biosorption mechanism and biomass generation. The results pave the way for innovative biotechnological applications such as biofertilizers and feedstock for bioethanol/ biodiesel production, thus promoting more sustainable management practices within the dairy industry.

Microalgae biofilm system as an efficient tool for wastewater remediation and potential bioresources for pharmaceutical product production: an overview

The role of microalgae in wastewater remediation and metabolite production has been well documented, but the limitations of microalgae harvesting and low biomass production call for a more sustainable method of microalgae utilization. The current review gives an insight on how microalgae biofilms can be utilized as a more efficient system for wastewater remediation and as potential source of metabolite for pharmaceutical product production. The review affirms that the extracellular polymeric substance (EPS) is the vital component of the microalgae biofilm because it influences the spatial organization of the organisms forming microalgae biofilm. The EPS is also responsible for the ease interaction between organisms forming microalgae biofilm. This review restate the crucial role play by EPS in the removal of heavy metals from water to be due to the presence of binding sites on its surface. This review also attribute the ability of microalgae biofilm to bio-transform organic pollutant to be dependent on enzymatic activities and the production of reactive oxygen species (ROS). The review assert that during the treatment of wastewater, the wastewater pollutants induce oxidative stress on microalgae biofilms. The response of the microalgae biofilm toward counteracting the stress induced by ROS leads to production of metabolites. These metabolites are important tools that can be harness for the production of pharmaceutical products.