GABA production from buckwheat derived probiotics (Cytobacillus oceanisediminis): a promising approach for neurological health enhancement : Buckwheat-Derived Probiotics for Neurological Benefits.

Depression is a widespread neurological disorder, increasing the demand for safe, natural therapeutic alternatives. Since depression is a common neurological condition, there is a growing need for safe, all-natural treatment options. Mood regulation is significantly influenced by gamma-aminobutyric acid (GABA), and microbially synthesized GABA has created focus for potential psychobiotic uses. In this study, a probiotic strain that produces GABA was isolated from fermented buckwheat, and its functional and antidepressant potential was assessed both in vitro and in vivo. A strain of Cytobacillus oceanisediminis (G4) was found through screening, and GABA production was verified by TLC and quantified using HPLC. G4 isolate generated 152 µg/mL of GABA with a 4.61-minute retention period. Additionally, the strain showed significant anti-inflammatory properties and antioxidant activity. Foxtail millet was chosen as a fermentation substrate for in vivo testing because of its prebiotic significance. Fermented millet containing G4 decreased immobility (≈ 42% reduction, p < 0.05) and enhanced neurotransmitter and stress biomarkers, such as dopamine, serotonin, noradrenaline, and corticosterone, according to behavioral analysis in a mouse model (open field, tail suspension, and novelty-suppressed feeding tests). Overall, the results indicate that strain G4 has potential as psychobiotic candidate with antidepressant, anti-inflammatory, and antioxidant-like properties; however, additional clinical validation and optimization are needed.