Provide are beneficial bacteria that can be beneficially applied across a wide range of age groups and a composition containing the same. Bifidobacterium longum subspecies longum NITE BP-02568 and/or Bifidobacterium longum subspecies longum NITE BP-02569; and Bifidobacterium longum subspecies longum, having utilization ability for 2'-fucosyllactose are also provided. More preferably, bacteria having utilization ability for carbohydrates arabinoxylan, arabinan, and pectic galactan; and a composition containing the bacteria are also provided. More preferably, a composition containing 2'-fucosyllactose are also provided. More preferably, a composition containing at least one carbohydrate selected from the group consisting of arabinoxylan, arabinan, pectic galactan, and oligosaccharides derived therefrom or containing at least a carbohydrate derived from a gramineous plant or a carbohydrate derived from a solanaceous plant are also provided.