Potential Antioxidant and Antiproliferative Activities of a Hot-water Extract from the Root of Tonh Khidum

In this study, for the first time, the possible antioxidant and antiproliferative activities of a hot-water extract (TW100) from the root of Tonh khidum (Actinidia kolomikta Maxim) were examined in vitro. Total phenolic compound, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and superoxide dismutase (SOD)-like activity assays were utilized to investigate its antioxidant activity. As a result, TW100 showed a strong antioxidant activity. The total phenolic content of TW100 was 143 μg gallic acid equivalents/mg. The SOD-like activity of TW100 was 666,667 U/g extract, and the DPPH radical-scavenging activity was 129 μg/ml at EC(50) which was one third of vitamin E (40 μg/ml). The antiproliferative effects and ability of the extracts to induce apoptosis were studied in vitro using human cervical cancer ME-180 cells. Results showed that TW100 inhibited the proliferation of ME-180 cells in a dose- and time-dependent manner except at a low concentration (10 μg/ml) with an EC(50) at 24, 48 and 72 h of 36.28, 30.55 and 29.78 μg/ml, respectively. TW100 also induced apoptosis as determined by a nuclear fragmentation assay and an analysis of flow cytometry. In conclusion, the hot-water extract from the root of Tonh khidum possesses potential antioxidant and antiproliferative activities.