The present study aimed to valorize rainbow trout (Oncorhynchus mykiss) processing waste through enzymatic hydrolysis using Alcalase and Flavourzyme, to produce protein hydrolysates with enhanced biofunctional properties. Hydrolysates were evaluated for their chemical composition, antimicrobial activity, antioxidant capacity, and molecular effects on Pseudomonas aeruginosa. Biochemical analysis revealed that enzymatic treatment significantly increased protein content and reduced moisture levels compared to crude extracts. Antimicrobial assays showed that while crude proteins exhibited no inhibitory effect, hydrolysates particularly those derived from Alcalase demonstrated clear inhibition zones against P. aeruginosa. Quantitative PCR confirmed microbial suppression by showing delayed amplification curves in treated samples. Antioxidant activity, measured via IC₅₀ values, indicated that Alcalase-generated hydrolysates possessed superior radical-scavenging capacity. The observed bioactivity was closely linked to peptide size distribution and enzyme specificity. These findings suggest that rainbow trout waste hydrolysates are promising candidates for use as natural antimicrobial and antioxidant agents in food, pharmaceutical, and environmental applications. Further studies are recommended to isolate and characterize the active peptides and assess their efficacy in real-world systems.
Keywords: Pseudomonas aeruginosa; Antimicrobial peptides; Enzymatic hydrolysis; Protein hydrolysates; Rainbow trout waste.
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