Purification and Identification of Cytotoxic Compounds from the Root of Rumex crispus L.

Abstract

Background: In the present study, we identified two cytotoxic compounds from the root of Rumex crispus L. using a bioassaybased method. Methods and Results: Compared with the other fractions, the diethyl ether (Et 2 O) fraction of R. crispus root extract exhibited the strongest of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect [scavenging concentration 50% (SC 50 ) = 63.8 ± 1.47 ㎍/㎖], nitric oxide (NO) production inhibitory effect on the mouse macrophage cell line RAW264.7 [inhibitory concentration 50% (IC 50 ) = 60.9 ± 7.52 ㎍/㎖] and cytotoxicity effect on the human hepatoma cell line, HepG2 [lethal concentration 50% (LC 50 ) = 115.4 ± 1.86 ㎍/㎖]. According to the bioassay-based method, two cytotoxic compounds were purified from the Et 2 O fraction by using column chromatography and preparative high performance liquid chromatography (prep-HPLC). These two compounds were identified as parietin and chrysophanol by using nuclear magnetic resonance (NMR) and liquid chromatography quadruple time of flight mass spectrometry (LC-QTOF-MS). In addition, both parietin and chrysophanol exhibited a cytotoxicity effect on HepG2 cells, their LC 50 values were 169.1 ± 17.67 µM and 111.5 ± 6.62 µM, respectively. Conclusions: Parietin and chrysophanol isolated from the Et 2 O fraction of the R. crispus root extract showed cytotoxicity in HepG2 cell.

Anti-Proliferative and Apoptotic Activities of Rumex crispus

“…Another study has shown that, when tested in a human hepatoma cancer cell line (HepG2), Rumex crispus extract induces increased apoptosis through the activation of various caspase cascades and Bcl-2, Bax-mediated pathways [30]. Additional analytical and cancer bioassay studies on Rumex crispus by Cho et al identified two organically soluble phytochemical constituents, chrysophanol and parietin, exhibiting quantifiable cytotoxicity with an LC50 of approximately 115 µg/mL [31]. Based on these findings, we know that Rumex crispus contains anti-proliferative and cytotoxic phytochemicals with the potential for cancer therapeutics and that our method produces similar results with aqueous whole-leaf extracts, while producing fractions which not only inhibit cancer cells but induce apoptotic cellular-signaling pathways.…”