Purification, Characterization, and Antimicrobial Activity of Lysozyme Obtained from the Mucus of Nile Tilapia (Oreochromis niloticus).

Lysozyme is an antimicrobial enzyme present in animal secretions with applications in food, pharmaceutical, and biotechnological industries. This study purified and characterized lysozyme from Nile tilapia (Oreochromis niloticus) mucus as a sustainable alternative source and evaluated its antimicrobial activity. Purification via crystallization and ultrafiltration yielded 40.4% recovery and 352.86 U/mg activity. The enzyme showed optimal activity at pH 6.0 and 45 °C, remaining stable between pH 5.0-8.0 and up to 65 °C. It was resistant to Ca²⁺ and Mn²⁺ and stable in organic solvents. Compared to commercial lysozyme, it exhibited higher catalytic efficiency, highlighting its industrial potential.