Table 4.

Antimicrobial activity of four bitter gentian tea decoctions, gentiopicroside (G) and loganic acid-6′-O-β-d-glucoside (LG), MIC, μg/mL ^a.

Microorganism	G. algida	G. decumbens	G. macrophylla	G. triflora	G	LG	PC b
B. subtillis	100	400	400	200	200	400	4.0
S. aureus	200	800	400	400	200	>800	4.0
E. faecalis	100	200	200	200	100	400	32.0
E. coli	100	400	400	200	100	400	2.0
P. aeruginosa	100	800	800	400	400	>800	16.0
C. albicans	200	>800	>800	800	400	>800	8.0

^a Lowest concentration preventing visible grow; ^b Positive control—streptomycin, except C. albicans—nystatin.