Pomegranate (Punica granatum L.) Peel Extracts as Antimicrobial and Antioxidant Additives Used in Alfalfa Sprouts

• Published in: Foods 2022-08, Vol.11 (17), p.2588
• Main Authors: Cruz-Valenzuela, Manuel Reynaldo, Ayala-Soto, Rosa E, Ayala-Zavala, Jesus Fernando, Espinoza-Silva, Brenda A, González-Aguilar, Gustavo A, Martín-Belloso, Olga, Soliva-Fortuny, Robert, Nazzaro, Filomena, Fratianni, Florinda, Tapia-Rodríguez, Melvin R, Bernal-Mercado, Ariadna Thalia
• Format: Article
• Language: English
• Subjects: Acids; added value; Additives; Alfalfa; anti-quorum sensing agents; Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; Antioxidants; Bacteria; Candida tropicalis; Chromatography; Chromobacterium violaceum; Coliforms; Composition; Ethanol; Flavonoids; Food additives; food byproduct; Food contamination & poisoning; Food science; Food waste; Food wastes; Fruits; Listeria monocytogenes; Medicago sativa; natural food additive; Phenolic compounds; Phenols; Plant extracts; Pomegranate; Psychrophilic bacteria; Punica granatum; Quality management; Quorum sensing; Salmonella Typhimurium; Scavenging; Solvents; Vegetables; Violacein; Waste management
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods11172588

Aqueous and ethanolic pomegranate peel extracts (PPE) were studied as a source of phenolic compounds with antimicrobial, anti-quorum sensing, and antioxidant properties. The aqueous extract showed higher total phenolic and flavonoid content (153.43 mg GAE/g and 45.74, respectively) and antioxidant capacity (DPPH radical inhibition: 86.12%, ABTS radical scavenging capacity: 958.21 mg TE/dw) compared to the ethanolic extract. The main phenolic compounds identified by UPLC-DAD were chlorogenic and gallic acids. The aqueous PPE extract showed antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, Candida tropicalis (MICs 19–30 mg/mL), and anti-quorum sensing activity expressed as inhibition of Chromobacterium violaceum violacein production (%). The aqueous PPE extracts at 25 mg/mL applied on alfalfa sprouts reduced psychrophilic bacteria (1.12 Log CFU/100 g) and total coliforms (1.23 Log CFU/100 g) and increased the antioxidant capacity of the treated sprouts (55.13 µmol TE/100 g (DPPH) and 126.56 µmol TE/100 g (ABTS)) compared to untreated alfalfa. This study emphasizes PPE’s antioxidant and antimicrobial activities in alfalfa sprouts preservation.