Purification of optimally produced extracellular fungal lipases and their role in the remediation of oil-rich kitchen wastewater

Journal article, 2025

Wastewater containing oils and lipids can have major environmental consequences, such as water contamination, soil erosion, and harmful impacts on ecosystems and aquatic life. Therefore, to eliminate oils and fix these discharges for the benefit of the environment, proper treatment of wastewater is essential. In this regard, lipases can be applied to a variety of domestic and commercial wastewater biotreatment applications. Lipases in the current study were produced using A. niger (MG654699.1), C. albicans (ATCC10231), and A. sclerotigenum (MK732096.1). The SSF optimization revealed that the highest quantity of lipase was generated for selected strains at 30 °C along with an optimized size of inoculum and moisture content, i.e., 5 mL, and at pH 7 in the case of A. niger and C. albicans and pH 8 in the case of A. sclerotigenum. The A. niger lipase after purification showed a specific activity of 42.7 Umg⁻¹, fold purification of 2.29, percentage yield of 57.5 %, and molecular weight of 30 kDa. The C. albicans purified lipase exhibited a specific activity of 35.6 Umg⁻¹, a fold purification of 2.42, a percentage yield of 56.4 %, and a molecular weight of 45 kDa. The purified lipase from A. sclerotigenum showed a specific activity of 38.5 Umg⁻¹, a fold purification of 4.35, a percentage yield of 57.7 %, and a molecular weight of 80 kDa. The degradation of oil-rich wastewater by fungal lipases was confirmed by the FTIR analysis of the control and lipase-treated kitchen wastewater samples. The results showed that these fungal lipases could be used in the bioremediation of wastewater with significant amounts of oils and lipids.