It is an object of the present invention to provide a bacterial strain belonging to Lactobacillus brevis subspecies brevis, which has more potent antiallergic activity than the known lactic acid bacteria strains and produces γ-aminobutyric acid (GABA). It is another object of the present invention to provide beverages and foods containing cells of the aforementioned bacterial strain belonging to Lactobacillus brevis subspecies brevis, as well as antiallergic agents containing them as an active ingredient. The present invention provides a bacterial strain belonging to Lactobacillus brevis subspecies brevis, which: is capable of growing in effervescent alcoholic beverages, produces γ-aminobutyric acid (GABA), and has antiallergic activity.