The minimum inhibitory concentration (MIC) results (Table 5) partially coincided with those obtained in the agar diffusion method, because Gram-positive bacteria (S. aureus and L. monocytogenes) required smaller quantities of coffee extracts to induce growth inhibition. S. aureus showed the lowest MIC, needing only 5 mg/mL of Arabica spent coffee extract to inhibit the pathogen growth. However, it must be pointed out that coffee extracts with concentrations less than 160 mg had antibacterial activity against Gram-negative strains. A possible