Table 3.

Acetylcholinesterase inhibitory activity of main components of the essential oils of Callicarpa, Premna, Vitex, and Karomia species from Vietnam ^a.

Concentration (µg/mL)	(E)-β-Caryophyllene	β-Pinene	α-Humulene	Limonene	Caryophyllene Oxide	trans-Carveol	Galantamine b
500	79.05	86.54	72.83	90.82	74.00	76.90	---
100	52.89	58.86	44.27	67.73	16.95	55.34	---
20	26.28	28.88	25.10	27.04	0.49	16.79	---
4	6.09	20.92	19.37	18.17	−2.11	1.19	---
IC50 (μg/mL)	89.10 ± 6.10	71.45 ± 5.77	160.48 ± 13.48	53.16 ± 4.08	320.16 ± 13.47	102.88 ± 7.84	1.78 ± 0.13b
IC50 (μM)	436.0 ± 29.9	524.5 ± 42.4	785.3 ± 66.0	390.2 ± 30.0	1453 ± 61	675.8 ± 51.5	6.19 ± 0.45

^a Data are presented as IC₅₀ values ± standard deviations obtained graphically from four independent experiments carried out in triplicate. ^b Galantamine was tested at concentrations of 10, 2, 0.4, and 0.08 µg/mL.