Based on the growth profiles under different O2 concentrations, the Bifidobacterium species were classified into four classes: O2-hypersensitive, O2-sensitive, O2-tolerant, and microaerophilic.
Baseándose nos perfís de crecemento en diferentes concentracións de O2, as especies de Bifidobacterium foron clasificadas en catro clases: hipersensibles ao O2, sensibles ao O2, tolerantes ao O2, e microaerófilas.