Physicochemical properties and physiological activities of acai berry extract fermented by lactic acid bacteria

Abstract

This study was conducted to investigate the physicochemical properties and physiological activities of acai berry extract fermented by lactic acid bacteria (LAB). The acai berry extract was prepared according using fermentation times ranging from 0 to 72 h. The viable cell count of lactic acid bacteria increased to 7.38 log CFU/mL after 48 h fermentation, while pH was 4.20, and the acidity had increased to 0.54%. In addition, total sugar and total anthocyanin contents were 51.50 g/100 g and 141.83 mg/L at 0 h fermentation, respectively; after 48 h, total sugar content decreased to 41.86 g/100 g, while after 72, total anthocyanin content increased to 182.74 mg/L. Furthermore, after 48 h, total phenolic, flavonoid, and proanthocyanidin contents increased to 34.74, 25.88, and 3.59 g/100 g, respectively. The DPPH and ABTS radical scavenging activities at 48 h were also determined, and these were found to be 81.25 and 83.46% at a concentration of 1,000 μg/mL, respectively. Moreover, the FRAP and reducing power of the fermented acai berry extract at 48 h were 0.97 μM and 1.10 at 1,000 μg/mL, respectively. Additional, the protective effect against oxidative stress in L132 cells was 89.60% after 48 h fermentation. The obtained results therefore suggested that fermented acai berry extract has the potential for application as a functional processing material in the food industry.