An appropriate strain of Bacillus spp. derived from traditional
Korean fermented foods was selected for fermentation of black rice bran, and the
fermented bran’s nutritional components were analyzed. Among 18 isolated
Bacillus spp. strains, the five (KU3, KU24, KU28, KU611,
and KU612) that exhibited both amylolytic and proteolytic activities were
selected for fermentation. Among these, Bacillus sp. KU3 showed
notable dual enzymatic activity. During fermentation in black rice bran medium,
Bacillus sp. KU3 increased from 5.83 to 7.83 Log CFU/mL
after 24 h. The KU3 strain was identified as Bacillus subtilis
using an API 50 CHB kit and 16S rRNA sequencing. Black rice bran (4% w/v) was
fermented with B. subtilis KU3 at 37°C, 150 rpm for 24
h. Following fermentation, the main component of the fermented black rice bran
was carbohydrate (77.13%). An increase in ash content was observed, while other
nutritional components showed no significant changes. These results suggest that
B. subtilis KU3 is a viable strain for black rice bran
fermentation.