Bioremediation of Pulp and Paper Mill Wastewater Using Isolated Fungal and Bacterial Strains

Pulp and paper mill wastewater contains high concentrations of toxic pollutants, including lignin and aromatic compounds, which contribute to its dark coloration and pose environmental hazards. Improper discharge of this wastewater can result in severe ecological consequences, such as oxygen depletion, carcinogenic effects, and aquatic toxicity. Various treatment methods, including physicochemical and biological approaches, have been used to address this issue. Among these, biological treatment with microorganisms, particularly bacteria and fungi, has gained attention for its efficiency and sustainability. Bacteria such as Bacillus sp. and Pseudomonas sp. exhibit adaptability across different pH ranges and produce ligninolytic enzymes that aid in pollutant degradation. In contrast, white-rot fungi, including Phanerochaete chrysosporium and Trametes versicolor, secrete potent extracellular enzymes that break down lignin and other complex organic pollutants. This review explores the physicochemical properties of pulp and paper mill wastewater, evaluates bacterial and fungal degradation processes, and compares their efficiency in reducing chemical oxygen demand (COD), biochemical oxygen demand (BOD), and lignin content. It also discusses future strategies for optimizing microbial consortia and enhancing enzymatic activity for large-scale wastewater treatment.