18B-14

H.-J. KIM, Department of Food Science and Human Nutrition, Clemson University, 224 Poole Ag. Center, Clemson, SC 29634, F. Chen, Dept. of Food Science and Human Nutrition, Clemson Univ., 224 Poole Ag. Center, Clemson, SC 29634, and G.-Q. He, Dept. of Food Science and Human Nutrition, Zhejiang Univ., Kaixuan Road 268, Hangzhou/Zhejiang Province, 310029, China.

Leaves of the Camellia sinesis are used to make tea that is one of the most popular non-alcoholic drinks worldwide and gaining further research interest by its health-promoting benefits due to the bioactive polyphenols. However, Camellia olifera, which is a very close cousin to Camellia sinesis and commonly used to extract tea seed oil, has not been studied intensively. In this study, tea seed of Camellia olifera is investigated for its inherent antioxidants. The methanolic extract of dried tea seed is evaluated by two different assays: 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and metal chelating assay. The results showed that the extract possessed strong free radical scavenging activity and metal chelating activity compared with standard antioxidants such as butylated hydroxytoluene (BHT) and Vitamin C in the DPPH assay and ethylene diaminetetraacetic acid (EDTA) in the metal chelating assay. Two μg of the dried seed methanolic extract exhibited about 56% free radical scavenging activity in the DPPH assay, while 10 μM of BHT and Vitamin C exhibited 43% and 40% respectively. By contrast, 5 μg of the tea seed methanolic extract was similar to that of 0.1 μM EDTA in the metal chelating activity for 56%. Antioxidants were separated and tentatively identified using C₁₈-HPLC and GC-MS. In addition, tea seed methanolic extrac exhibited a strong antiproliferative activity against the MCF-7 cancer cells. This result demonstrated that tea seed might be another good source of the natural bioactive antioxidants besides its major product-tea seed oil.

Session 18B, Food Chemistry: Antioxidant and bioactive agents
2:00 PM - 5:30 PM, Sunday PM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana