Table 2. The MICs of PB combined with compound B1 at different concentrations.

Compound B1 concentration	MIC of PB (MIC μg ml–1)	Fold reduction
0 μg ml–1	32	1
1 μg ml–1	8	4
2 μg ml–1	2	16
4 μg ml–1	0.5	64
8 μg ml–1	0.25	128
16 μg ml–1	0.25	128