GC-MS Analysis and Study of the Antimicrobial Activity of Citrus paradisi, Citrus aurantifolia, and Citrus sinensis Peel Essential Oils as Hand Sanitizer

Table 1

Zone of inhibition (mm) of the citrus essential oils and the control against test organisms.

Test organism		MDIZ
		Grapefruit essential oil	Lime essential oil	Orange essential oil	Commercial 78% alcohol hand sanitizer
Gram-negative bacteria	E. coli	10 ± 0.41	12 ± 0.98	13 ± 1.41	18 ± 1.22
	P. aeruginosa	14 ± 1.47	15 ± 1.79	12 ± 1.10	17 ± 2.32
Gram-positive bacteria	S. aureus	10 ± 0.89	15 ± 3.08	10 ± 0.41	15 ± 1.17
	B. subtilis	13 ± 1.21	16 ± 0.82	13 ± 1.03	17 ± 1.75
Fungi	C. albicans	14 ± 1.33	17 ± 1.75	14 ± 1.03	19 ± 1.37

Numbers indicate mean diameter of growth inhibition zone (MDIZ)^∗ in mm ± standard deviation. Interpretation of results: <9 mm zone was considered as inactive; 9–12 mm as partially active; 13–18 mm was active and >18 mm as very active, (-): No inhibition zone.