Effect of Extraction Solvent and Harvest Time on Recovery of Bioactive Com-pounds, Antioxidant and Cancer Cell Growth Inhibition Activities of Korean Ca-mellia mistletoe

Abstract

This study aimed to determine the phytochemical profiles,in vitroantioxidant and antiproliferative properties of KoreanCamellia mistletoe(Korthalsella japon-ica(Thunb.) Engl.) depending on the harvest time (August and November) and sol-vent (100% methanol, 70% ethanol, and hot water). TheCamellia japonicaL. mistle-toe extracts were analyzed for total phenol, flavonoid, carotenoid, and L-ascorbic acid contents and antioxidant properties such as scavenging capacities (1,1-diphenyl-2-pic-rylhydrazyl (DPPH) and NO•),ferrous ion chelating and reducing power. Concur-rently, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) as-say was used to assess the antiproliferative properties against human cancer cell lines; MCF (human breast cancer cells), HeLa (human cervical cancer cells), A375 (human malignant melanoma cells), HCT116 (human colon cancer cells), HepG2 (human liver cancer cells) and A549 (human non-small cell lung adenocarcinoma cells). The results showed that extraction solvent and harvest time had significant impacts on antioxidant and anticancer activities and selectivity for free phenolic compounds inCamellia ja-ponicaL. mistletoe. Among all the tested extracts, the highest amounts of total phe-nolic and total flavonoids content were found in ethanol extracts ofCamellia japon-icaL. mistletoe harvested in November, while the methanol extracts ofCamellia ja-ponicaL. mistletoe collected in August showed the highest contents of total carote-noids and L-ascorbic acidscompared to the other tested extracts. Additionally, the highest NO•radical scavenging activity was found in ethanol extracts, whereas the strongest DPPH radical scavenging activity was found in methanol extracts ofCamel-lia japonicaL. mistletoe harvested in November. Furthermore, methanol extracts showed much higher antiproliferative activity against all human cancer cells than eth-anol extracts ofCamellia japonicaL. mistletoe harvested in November. In conclusion, the antioxidant and anticancer properties ofCamellia japonicaL. mistletoe showed significant dependence on the extraction solvent type and harvest time. With optimum harvest time and extraction solvent, they boast a wide range of promising medical, pharmaceutical, and food applications