Protein hydrolysates for agricultural formulations: LC-MS/MS identification of dipeptides and field evaluation in soybean

Abstract

This study establishes LC-NL(46)-MS/MS as a selective and efficient method for profiling bioactive dipeptides in protein hydrolysates, addressing limitations of conventional full-scan analyses. Four formulations were evaluated: two commercial biostimulants (Biost1 and Biost2) and two prototypes (MVP1 and MVP2). Computational predictions revealed non-toxic dipeptides with diverse bioactivities, including ACE and DPP-IV inhibition, antioxidant effects, and similarities to CLE peptide fragments involved in plant signaling. MVP1 exhibited superior peptide diversity and CLE-related sequences, suggesting enhanced biostimulant potential. Field trials in soybean demonstrated the safety of these hydrolysates, with no negative impacts on growth or yield, though statistical significance was not achieved. Qualitative productivity gains (up to 8.7%) in MVP1 highlight their role as sustainable signaling mediators. These findings provide a foundation for quality control in biostimulant production and future research on combined formulations under stress conditions, emphasizing the dual function of protein hydrolysates as nutrient carriers and sources of bioactive peptides for agricultural applications.