Chemical constituents from roots of Zizyphus rugosa Lam. and roots of Antidesma acidum Retz.

Abstract

The investigation for chemical constituents from the CH₂Cl₂ and MeOH crude extracts of the roots of Zizyphus rugosa Lam. led to the isolation of nine triterpeniods; lupeol (1.1), betulin (1.2), betulinic aldehyde (1.3), betulinic acid (1.4), alphitolic acid (1.5), euscaphic acid (1.6), zizyberenalic acid (1.7), a mixure of β-sitosterol (1.8) and stigmasterol (1.9), one coumarin; scopoletin (1.10) and four flavonoids; kaempferol (1.11), afzelin (1.12), quercitrin (1.13) and (+)-catechin (1.14). The chemical structures of all isolated compounds were characterized according to physical means of spectral analysis as well as comparison with the previous literature data. All of the isolated compounds (1.1-1.14) were evaluated for their cytotoxicity on KB and HeLa cells. Compounds 1.2 and 1.7 exhibited moderate cytotoxicity against both KB and HeLa cells, with IC₅₀ values of 10.0, 5.5 µg/mL and 9.5, 13.0 µg/mL, respectively, while compound 1.4 showed only moderate cytotoxic against on HeLa cells (IC₅₀ = 10.0 µg/mL). The phytochemical investigation of the CH₂Cl₂ and MeOH crude extracts from the roots of A.acidum Retz. afforded a new natural (synthetically known) compound, corylifolin (2.2), togather with sixteen compounds including antidesmol (2.1), mellein (2.3), a mixture of β–stitosterol (2.4) and stigmasterol (2.5), 5-cholesten-3β-ol (2.6) and 4-cholesten-3-one (2.7), 3-(1,1-dimethylallyl)-scopoletin (2.8), 5,7-dihydroxy-2-eicosyl-chromone (2.9), 2,5-dimethoxy-1,4-bezoquinone (2.10), barbatumol A (2.11), N-trans-feruloyltyramine (2.12), syringic aldehyde (2.13), p-hydroxybenzoic acid (2.14), taxifolin (2.15), (+)-catechin (2.16) and (-)-gallocatechin (2.17). Compounds 2.9 and 2.10 showed only good cytotoxicity against on HeLa cells (with IC₅₀ values of 3.9 and 1.6 µg/mL) and compounds 2.12, 2.14 and 2.17 showed only moderate cytotoxicity against on HeLa cells (with IC₅₀ values of 12.3, 10.8 and 14.9 µg/mL), while compounds 2.10 and 2.12 showed only moderate cytotoxicity against on KB cells (with IC₅₀ values of 4.9 and 7.8 µg/mL). The investigation and evaluation for the AChE and BuChE inhibitory activity using Ellman colorimetric method indicated that compounds 2.2, 2.3 and 2.12 showed low inhibitory activity toward only BuChE with percentage inhibitory activity values of 47.78, 40.29 and 43.62, respectively.