Pre-germinative Enzymatic Activities in Vigna unguiculata with Focus on Proteolytic Enzymes Involved in Storage Protein Mobilization

Imbibition and germination are sequential and interconnected phases that initiate seedling development through coordinated biochemical processes. In legume species, these stages involve the activation of enzymes required for the mobilization of storage reserves. In this study, enzymatic activities associated with imbibition and germination of Vigna unguiculata seeds were investigated, with particular focus on proteolytic enzymes. Protease activity was detected both during water imbibition and throughout germination, indicating that proteolytic processes are initiated prior to visible germination events. A protease associated with storage protein degradation was purified and subjected to biochemical characterization. The detection of protease activity during imbibition highlights the importance of pre-germinative enzymatic events and supports the concept of multifunctional enzymes operating at the interface between metabolism and defense in Vigna unguiculata seeds.