GABA-fortified synbiotic guava beverage: formulation and evaluation of neuroprotective properties using cell-based assays

Abstract

Abstract In recent years, the use of fermented fruit juices to offer protection against mental illness has been increasing enormously. The present study, aimed at formulating a synbiotic fruit beverage for mental well-being using fructo-oligosaccharide (FOS), Gamma-aminobutyric acid (GABA) and Lactobacillus rhamnosus. Guava extract (abbreviated as fruit extract, FE; 10%) supplemented with FOS (1%) fermented for 48 h using L. rhamnosus, was then fortified with 0.05% GABA (FE + FOS + GABA). This GABA-fortified fermented guava beverage exhibited significant in-vitro antioxidant activity as measured by using 2,2-diphenyl-1-picrylhydrazyl (IC50 value of 0.451 ± 0.05 mg/ml) and ferrous reducing antioxidant capacity (A700 nm value of 0.68 ± 0.06) assays. Fermentation also enhanced total phenolics and flavonoids by 27.63% and 27.41%, respectively. Furthermore, GABA-fortified fermented guava beverage showed a significant neuroprotective effect by negatively modulating oxidative stress and upregulating activity of antioxidant enzymes (superoxide dismutase and catalase) in rotenone treated neuronal cell lines. Taken together, our research findings clearly indicate the propensity of GABA-fortified fermented guava beverage to protect against rotenone mediated neuronal cell damage. Even though the underlying molecular mechanisms need further research, in conclusion, our study demonstrates that the GABA-fortified fermented guava beverage effectively confers neuroprotective effects in vitro, suggesting its potential as a functional beverage for promoting brain health. Graphical Abstract

Keywords

• Fruit extract
• Guava
• Prebiotics
• Probiotics
• Fermentation
• Fortification