Fruit waste represents over 40% of global food loss and contributes significantly to methane emissions. This project aimed to develop a sustainable method for producing antimicrobial peptides (AMPs) from fruit peel residues using genetically modified Saccharomyces cerevisiae Ethanol Red TDH1 (ER TDH1) and evaluate their potential against microbial pathogens.

Peels of mango, pineapple, banana, and apple were processed into must. The musts underwent acid hydrolysis, followed by alcoholic fermentation with S. cerevisiae ER TDH1. After fermentation, the peptides <10 kDa were extracted via ultrafiltration from the cell-free supernatant and tested against microbial pathogens, E. coli, P. aeruginosa, S. aureus, and C. albicans. Glucose, fructose, and ethanol levels were monitored throughout. For peptide production comparison, alcoholic fermentation in a synthetic must was performed, yielding higher ethanol (≈14 g/L) than fruit must (≈3 g/L). The <10 kDa peptide fraction from fruit must showed strong inhibition of S. aureus and C. albicans (MIC = 1.47 mg/mL), while synthetic must peptides performed better against E. coli and P. aeruginosa (MIC = 1.47 mg/mL). AMPs derived from fruit waste via fermentation show promising antimicrobial activity, particularly against Gram-positive bacteria and yeast, highlighting their potential as sustainable, natural preservatives for pharmaceutical or food product applications.