Acetylcholinesterase Inhibitory and Antioxidant Activity of the Compounds Isolated from Vanda roxburghii

Figure 4

Reducing power and total antioxidant activities of the isolated compounds. (a) Reducing power. Absorbance (100 μg/ml, 700 nm): SA, 0.667 ± 0.035; VA, 0.746 ± 0.005; DC, 0.894 ± 0.014; GI, 1.865 ± 0.030; CA, 1.964 ± 0.019. (b) Total antioxidant activity. Absorbance (80 μg/ml, 695 nm): SA, 0.336 ± 0.009; VA, 0.716 ± 0.020; DC, 0.735 ± 0.022; GI, 0.848 ± 0.029; CA, 1.739 ± 0.049. Catechin (CA) was used as a reference antioxidant. Results represent mean ± SD (n = 3). Compound 1 had no activity and was not shown. Means with different letters (a–e) differ significantly (). SA, syringaldehyde; VA, vanillin; DC, dihydroconiferyl dihydro-p-coumarate; GI, gigantol; CA, catechin.

(a)

(b)