Urease (urea amidohydrolase; EC 3.5.1.5) is an enzyme that facilitates the hydrolysis of urea, primarily synthesized by microorganisms, including algae, fungi, and bacteria. Animals release urea into the soil. Consequently, soil exhibits significant urease activity. Urea in the soil is continuously utilized by microorganisms, particularly bacteria, which decompose it into ammonia and carbon dioxide. Ammonium is frequently employed alongside urea fertilizer to enhance its hydrolysis in the soil. Urease-producing bacteria play important roles in human pathogenicity, biocementation, and soil fertilization, contributing to conditions such as urinary stones, pyelonephritis, and gastric ulceration. This study aimed to produce urease from soil samples, utilizing cost-effective sources and minimizing expenses. It considered the optimization of various culture conditions, including fermentation effects, protein determination, pH, temperature, substrate concentration, and kinetic parameters. Protein determination was employed for the partial purification and assessment of protein levels. Aspergillus niger was cultivated on media supplemented with chloramphenicol to suppress bacterial proliferation. The fungi exhibiting the highest growth were subcultured to establish a pure culture. These fungi underwent urease screening utilizing Christensen’s urea agar, where identification was based on the pink coloration resulting from urease degradation, subsequently employed for fermentation. Solid-state fermentation utilized cassava peel powder as the exclusive carbon source. The fermentation period lasted eight days. Day five exhibited the highest production, characterized by an enzyme activity of 1.47 µM. The influence of pH and temperature on the crude enzyme indicated that the optimal pH and temperature for enzyme activity were 7 and 35°C, respectively, with kinetic parameters (Vmax and Km) recorded at 6.173 and 5.531, respectively. This research investigates a novel and economical method for enzyme production by employing cassava peels, an agro-industrial byproduct, as a carbon source for urease synthesis. The study identified cassava as a potential alternative income source for cassava-producing communities, while also addressing challenges related to food-processing waste management. This study advances green biotechnology, circular economy practices, and the creation of cost-effective, environmentally friendly enzyme production systems that support sustainable development goals.
