Antimicrobial and antioxidant competence of sustainable grumixama leaves extracts in nanoemulsion system

The spontaneous emulsification method was used to produce nanoemulsions loaded with grumixama leaves extracts (GLE) to protect and improve its functionality as a natural additive in food. Nanoemulsions were characterized for physicochemical stability, morphology, thermal analyses, antioxidant capacity, and antimicrobial activity. The formulations showed encapsulation efficiency (EE%) >89%, sizes between 182 and 290 nm, low polydispersity, and zeta potential near -30mV. The formulations were kinetically stable since these parameters remained constant for up to 180 days at 4°C. The nanoemulsion with 125 mg GLE exhibited better droplet structure, which favored greater phenolic compounds protection and thermal resistance. The antioxidant capacity of all formulations remained stable over 30 days. The nanoemulsions acted as a bactericidal agent (MBC/MIC ratio ≤ 4) against Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes strains. However, GLE-loaded nanoemulsions offer a sustainable and functional alternative for use as a natural additive to meet trends such as a clean label.