Physiochemical properties and bioactivities of tea seed ( Camellia oleifera) oil.

摘要

Tea seed (Camellia oleifera) oil has been used for cooking in China and other Asian countries for more than a thousand years. This study determined the fatty acid composition and tocopherol content through chromatography-flame ionization (GC-FID) and high performance liquid chromatography-UV (HPLC-UV), respectively. The results showed that the tea seed oil (TSE) was mainly composed of 18.30% palmitic acid (C16:0), 54.95% oleic acid (C18:1), 22.41% linoleic acid (C18:2), and 0.17% linolenic acid (C18:3). Its alpha-tocopherol content was found the 21.13 mg/100 g oil. Moreover, the antioxidant capacities of methanolic extract of TSE and the remaining meal (Meal)were determined using the following four in vitro antioxidant methods, total phenolic content (TPC) assay, trolox equivalent antioxidant capacity (TEAC) assay, 2,2-di-phenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and metal chelating capacity. The TPC and the TEAC of the Meal were 23.3 mg gallic acid equivalent/g and 4.42 muM Trolox/g, respectively, 7 to 15 times higher than those of the TSE. In addition, the metal chelating capacity of Meal can reach 90% at 25 mg sample equivalent/mL. Moreover, the TSE and the Meal showed different levels of antiproliferative activities against the following three cancer cell lines: SiHa (human uterus cancer cell line), MCF-7 (human breast cancer cell line) and HT-29 (human colon cancer cell line). The IC50 values of TSE and Meal were 146.70 and 2.92 mg sample equivalent/mL for SiHa, 236.20 and 2.94 mg sample equivalent/mL for MCF-7, and 155.20 and 1.52 mg sample equivalent/mL for HT-29. In addition, comparative analysis of the TSE and olive oil showed that both dietary edible oils had similar iodine values, though the former exhibited a lower PV-Fox value in the study. These results demonstrate TSE and Meal are rich in bioactive chemicals and provide health benefits.