Kunitz-type protease inhibitor from potato inhibits activities of Bothrops jararaca snake venom

Snakebite envenoming is a global health problem, leading to the search for different sources of biomolecules to supplement the current antivenom therapy. Snake venom serine proteases are abundant in Viperidae venoms and are responsible for disruptions in the hemostatic system. Previous studies have shown that English potato (Solanum tuberosum) is a source of Kunitz-type serine protease inhibitors. In this work, a Kunitz-type inhibitor from S. tuberosum was isolated, and its inhibitory capacity on the proteolytic activities of Bothrops jararaca snake venom was evaluated. Initially, the potato extract was subjected to a three-step purification protocol (gel filtration, ion exchange, and hydrophobic interaction), resulting in two fractions: one containing an isolated 20 kDa protein and the other containing two bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis. Both fractions showed interaction with the snake venom in Western blotting assay. They also showed inhibitory ability on both coagulant and proteolytic activities, revealing a potential biomolecule to enhance the treatment of coagulopathy caused by envenomation.