Table 1.

Minimum inhibitory concentration (MIC, mg/mL) values and fractional inhibitory concentration (FIC) index of natural antimicrobials against S. mutans and S. sobrinus, before and after nanoencapsulation

	Antimicrobials	S. mutans ATCC 25175		S. sobrinus ATCC 27351
		Free	NPs	Free	NPs
MIC	Clove oil	0.5	0.5	0.5	0.5
	Thymol	0.5	0.5	0.5	0.5
	Naringin	1.0	1.0	1.0	1.0
	Naringenin	1.0	1.0	1.0	1.0
	Licorice	0.5	> 1.0	0.5	> 1.0
FIC	Clove oil + Thymol	0.75 (A)a	0.5 (S)	0.5 (S)	0.5 (S)

^aFIC index are interpreted as synergy (S, FIC ≤ 0.5), additive (A, 0.5 < FIC ≤ 1), indifference (I, 1 < FIC ≤ 4), or antagonism (AN, FIC > 4)