Antioxidative and Anticancer Activities of Various Solvent Fractions from the Leaf of Camellia japonica L.

To obtain basic information on the potential use of Camellia japonica leaf as a raw material in functional food, leaf antioxidant and anticancer activities were investigated. The radical-scavenging activity of various solvent fractions from the leaf, as shown by the DPPH radical test, increased in a dose-dependent manner, with the water fraction showing the highest activity. The reducing power of various solvent fractions from the leaf was also dose-dependent, and, again, the water fraction showed the highest reducing power. The water fraction showed strong antioxidant activity in the linoleic acid test and was also capable of scavenging nitrite in a dose-dependent manner. Proportions of 92.15% and 95.61% of available nitrite were scavenged by the water and butanol fractions, respectively, at levels of . Both butanol and water fractions exhibited strong inhibitory effects on the growth of human lung and colon cancer cells. The total phenolic contents of the butanol and water fractions were 216.26 mg/g and 220.68 mg/g, respectively. High-performance liquid chromatography (HPLC) showed that quercetin and epicatechin were the predominant phenolic compounds in the water fraction. The activities of this fraction are attributable to the presence of these phenolic compounds, particularly quercetin and epicatechin.