Results

			24-h IC₅₀^a		MIC^b
Test compound	24-h IC₅₀^a	MIC^b	RDCF^c	RDCO^d	24-h IC₅₀^a	MIC^b
Flor*	0.58 (0.04)	0.36 (0)
Oxy**	0.86 (0.07)	0.46 (0)
1	17.18 (0.75)	7.47 (0)	29.9 (0.5)	20.3 (2.4)	20.8 (0)	16.2 (0)
2	6.91 (3.55)	7.47 (0)	12.4 (6.9)	7.8 (3.6)	20.8 (0)	16.2 (0)
3	2.13 (0.11)	4.11 (3.36)	3.7 (0)	2.5 (0.3)	11.4 (9.3)	8.9 (7.3)
4	2.62 (0.23)	7.47 (0)	4.6 (0.1)	3.1 (0.5)	20.8 (0)	16.2 (0)
Mix	3.1 (0.49)	7.47 (0)	5.5 (1.2)	3.6 (0.3)	20.8 (0)	16.2 (0)

*Florfenicol; **Oxytetracyline HCl
^a24-h IC₅₀ = 50% inhibition concentration in mg/L.
^bMIC = Minimum inhibitory concentration in mg/L.
^cRDCF = Relative-to-drug-control florfenicol; values closer to 1.0 indicate higher antibacterial activity compared to florfenicol.
^dRDCO = Relative-to-drug-control oxytetracycline; values closer to 1.0 indicate higher antibacterial activity compared to oxytetracycline.

Table 1: Results of the bioassay evaluation of antimicrobial compounds from American sycamore leaves for antibacterial activity against Flavobacterium columnare ALM-00-173. Numbers in parentheses are the standard error of the mean.