Soybean Whey Bio-Processed Using D1501 Protects Neuronal PC12 Cells Against Oxidative Damage.

Soybean whey, as a byproduct of soybean industry, has caused considerable concern recently because of its abundant nutrients. To further utilize soybean whey, it was fermented with D1501, and the neuroprotective potency of this beverage was studied in the present work. The phenolic profile and antioxidant capacity of fermented soybean whey (FSBW) were analyzed. The neuroprotective effects were evaluated based on the hydrogen peroxide-stimulated oxidative damage model in a neural-like cell (PC12). Results demonstrated that soybean whey's phenolic contents and antioxidant activities were markedly improved after fermentation. Glycoside isoflavones were efficiently converted into aglycones by D1501. FSBW extract apparently increased cell viability, decreased reactive oxide species levels, and protected antioxidant enzymes in oxidative damage. Furthermore, FSBW effectively reduced apoptosis rate by inhibiting Bax protein and improving Bcl-2 and Bcl-xL proteins. FSBW ameliorated the cell cycle through the decrease of p21 protein and an increase of cyclin A protein. The findings of this study thus suggested that D1501-fermented soybean whey could potentially protect nerve cells against oxidative damage.