Synergistic Antibacterial Effects of Polyphenolic Compounds from Olive Mill Wastewater

Table 2

Minimal inhibitory concentration (MIC) of phenolic compounds against the Gram-positive (S. pyogenes and S. aureus) and Gram-negative bacteria (E. coli and K. pneumoniae). Each well contains ~10⁵ cfu. The results were obtained after incubation at 37°C for 24 h. NE represents no growth inhibition.

	Strain
	E. coli	S. pyogenes	K. Pneumoniae	S. aureus
Component (μg/mL)
AntiSolvent	1000	1000	NE	NE
Hydroxytyrosol	400	400	400	400
Tyrosol	600	600	600	NE
Gallic acid	NE	400	NE	200
Ascorbic acid	NE	1000	NE	NE
Caffeic acid	NE	NE	NE	NE
Ferulic acid	NE	NE	NE	NE
Coumaric acid	NE	NE	NE	NE
Cinnamic acid	NE	NE	NE	NE
Vanillic acid	NE	NE	NE	NE
Syringic acid	NE	NE	NE	NE
Protocatechuic acid	NE	NE	NE	NE