Protective Effects of Purple Sweet Potato Added to Bacillus subtilis-Fermented Soymilk against Amyloid beta-Induced Memory Impairment

Abstract

The present study focused on the protective effects of 5% purple sweet potato added to Bacillus subtilis-fermented soymilk (PFSM) under an Alzheimer's disease (AD) model using ICR mice induced by amyloid beta (Ab), which showed strong antioxidative activity against cognition impairment in a previous study. To observe memory and cognition abilities, T-maze, object cognition, and Morris water-maze tests were carried out. The A? injected groups showed impairments of cognition and memory. However, the oral administration of PFSM extract (100 and 200 mg/kg body weight/day for 7 days) improved cognition and memory. Furthermore, nitric oxide (NO) formation and lipid peroxidation were significantly elevated by Ab, whereas PFSM treatment significantly decreased NO formation and lipid peroxidation in the brain, liver, and kidneys. The present study suggests that PFSM improves memory deficit and cognition ability following Ab induction. The protective effects of PFSM against Aβ-induced impairments of memory and cognition are closely related to the attenuation of oxidative stress.