The cell of Bacillus subtilis is straight rod-shaped, no capsule, with flagella around the cell, and can move. It is Gram-positive, its spore is 0.6-0.9 × 1.0-1.5μm, ellipsoidal or cylindrical, in central or slightly deviated position of cell body, and the cell body is not dilated after spore is formed. It is a probiotic bacterium officially approved by U.S. Food and Drug Administration (FDA) in 1989 and the Ministry of Agriculture of China in 1999. The bacterium has single species, no drug resistance, no toxicity to animals and other features.
