TABLE 3.

MICs of antibiotics for acid-stressed^a bifidobacteria

Organism	MIC (μg/ml)b of the following antibioticc for the indicated organism:
	Amp	Clo	Pen	Van	Kan	Neo	Par	Str	Chl	Ery	Tet	Nis
B. animalis ATCC 27536	0.98	3.9	0.98	>500	500	250	500	125	1.9	1.9	62.5	3.9
B. bifidum R 0071	0.98	15.6	1.9	>500	0.98	250	250	250	7.8	0.98	31.2	1.9
B. bifidum ATCC 15696	Did not survive acid stress
B. bifidum BB12	0.98	0.98	0.98	>500	250	125	125	125	1.9	3.9	0.98	0.98
B. breve ATCC 15700	0.98	125	0.98	>500	500	125	125	125	62.5	3.9	250	3.9
B. breve R0070	3.9	15.6	1.9	>500	500	250	250	125	3.9	0.98	31.2	3.9
B. infantis ATCC 15697	0.98	125	0.98	0.98	500	250	250	250	0.98	3.9	125	0.98
B. longum ATCC 15707	3.9	15.6	0.98	>500	500	500	500	250	7.8	0.98	62.5	0.98
B. longum ATCC 15708	Did not survive acid stress
B. longum R0175	0.98	0.98	0.98	0.98	250	250	250	31.2	3.9	0.98	0.98	0.98
B. longum P/N 601377	0.98	0.98	0.98	>500	250	250	250	62.5	1.9	0.98	0.98	0.98
B. pseudolongum ATCC 25562	0.98	0.98	0.98	0.98	250	250	250	250	3.9	3.9	0.98	0.98
B. thermophilum ATCC 25866	3.9	31.2	0.98	>500	500	250	500	250	3.9	0.98	125	0.98

^aOrganisms were stressed for 60 min at pH 2.0, followed by 18 h of anaerobic growth in MRS broth, pH 6.5.

^bMedian of four repetitions.

^cAmp, ampicillin; Clo, cloxacillin; Pen, penicillin G; Van, vancomycin; Kan, kanamycin; Neo, neomycin; Par, paromomycin; Str, streptomycin; Chl, chloramphenicol; Ery, erythromycin; Tet, tetracycline hydrochloride; Nis, nisin A.