INVITRO ANTIOXIDANTS ACTIVITIES OF EXTRACTED FERMENTED WATER FROM CARICA PAPAYA FRUIT

Abstract This study investigated the antioxidant potential of naturally fermented unripe Carica papaya water over a 12-day fermentation period. Using four standardized assays—phosphomolybdate (TAC), DPPH, FRAP, and nitric oxide (NO) scavenging—the fermented product was compared to ascorbic acid as a reference standard. Results revealed that while the fermenting water exhibited strong and consistent DPPH radical scavenging activity (100%, matching ascorbic acid), its total antioxidant capacity (TAC) declined slightly from 72.03% (Day 3) to 66.12% (Day 12), and its ferric reducing power (FRAP) remained low (~9.32%) compared to the standard (67.60%). Nitric oxide scavenging decreased significantly from 207.79 nmol/mL (Day 3) to 108.10 nmol/mL (Day 9), suggesting time-dependent degradation of NO-inhibiting compounds. pH and titratable acidity measurements confirmed progressive acidification (pH 6.0 to 5.0), characteristic of lactic acid bacterial activity. The findings demonstrate that natural fermentation preserves potent free radical scavengers (likely phenolic compounds) but yields limited metal-reducing antioxidants. These results highlight the potential of fermented papaya water as a source of stable radical scavengers for nutraceutical applications, though further optimization is needed to enhance broader antioxidant capacities. Keywords: Carica papaya, natural fermentation, antioxidant activity, DPPH, FRAP, nitric oxide scavenging.