Table 6.

Minimmum biofilm inhibitory concentration (MBIC₅₀ µg mL⁻¹) of extracts from stingless bees (1—S. postica, 2—T. clavipes, 3—M. q. quadrifasciata, 4—T. fiebrigi).

Sample	Gram-Positive Bacteria			Gram-Negative Bacteria
	P. larvae ATCC 9545	B. cereus ATCC 10987	B. subtilis ATCC 6633	E. coli ATCC 11229
1	23.57 ± 2.53	1.45 ± 0.37	5.90 ± 0.90	280.86 ± 57.60 *
2	111.97 ± 25.51	0.06 ± 0.01	0.049 ± 0.001	53.39 ± 4.60
3	97.91 ± 4.06	0.04 ± 0.002	0.035 ± 0.001	50.76 ± 2.97
4	16.57 ± 2.00	0.21 ± 0.02	0.21 ± 0.011	311.47 ± 29.82

MBIC₅₀: minimum biofilm inhibitory concentration, defined as the lowest concentration of extract capable of reducing biofilm formation by 50% compared to the control assay (* IC₂₅, µg mL⁻¹).