Screening of antioxidant activity of fermented papaya

• Autor(a) principal: Leitão, Mariana
• Data de Publicação: 2023
• Outros Autores: Barreiros, Luísa, Moreira, Fernando, García, Pablo, Correia, Patrícia
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/23664
• topic: Acetic acid bacteria; Antioxidant activity; Fermented papaya; Papaya; Phenolic compounds

Papaya is the fruit of Carica papayaL., consumed for its beneficial proprieties, directlyor as a fermented fruitsupplement. Compare the total phenolic content (TPC) and the antioxidant activity (Ferric Reducing Antioxidant Power, FRAP) evolution in a variety of papaya fermentation experiments using fruit natural microorganisms (spontaneous fermentation) versus fermentation with Gluconobacter oxydansbioinoculation. Different papaya fermentations were performed: spontaneous (P1 and P2, during 7 days; P3, P4 and P5, during 9 days) and with bioinoculation (P6 and P7, during 9days). Then, TPC was determined according to the Folin-Ciocalteu (FC) procedure, mixing 250 μL of sample with 2.5 mL of FCreagent, followed by an addition of 2 mL of sodium carbonate solution (7.5 % w/v). This mixture wa sincubated at 45 °C for 15 minutes, and then kept in the dark at room temperature for 30 minutes. Absorbance was measured at 765 nm. The FRAP method was performed mixing 1.2 μL of freshly FRAP reagent with 40 μL of sample,and then incubating for 15 minutes at 37 °C. Absorbance was read at 593 nm. The lowest TPC was observed on day7of P4 (121.20±0.12 μg GAE·mL-1), and the highest content was observed on day 8 of P7 (260.18 ± 0.02 μg GAE·mL-1). TPC decreased from the first to the last day of fermentation in all tests, except for the tests where bioinoculation strategy was used. Those tests also showed a higher FRAP content, although from day 1 today 7, FRAP also slightly increased in P1, P2, and P3 (spontaneous fermentations). Antioxidant capacity increased as a result of fermentation with G. oxydans, probably due to the increased amount of phenolic compounds observed. The final product may be used as a functional food or cosmetic applications.