| Summary: | 碩士 === 國立嘉義大學 === 食品科學系碩士班 === 90 === The absicissed leaves of Terminalia catappa were extracted with ethanol, acetone, n-hexane, supercritical CO2 (SC-CO2) and boiling water, respectively and the extracts were subjected to Ames test using Salmonella typhimurium TA98 and TA100 as testing strains, neither toxicity nor mutagenicity of the extracts was detected up to a dose of 0.5mg/plate. SC-CO2 extracts showed the strongest antimutagenicity among all types of extracts. At the dose of 0.5mg/plate of SC-CO2 extracts, the mutagenicity of B[a]P (with S-9) was 75.5% of inhibition while 40.6% of the mutagenicity of MNNG (without S-9) was inhibited. After subjecting to GC-MS analysis, the active compound of squalene was presumptively identified and was rich in the SC-CO2 extracts of T. catappa leaves. When squalene was applied in mutagenicity test, a dose-response relationship was observed. When the SC-CO2 extracts and squalene were applied to the test of cytotoxicity, the growth of the Huh 7 and Chang liver cells were significantly inhibited by SC-CO2 extracts rather than by squalene. In comparison, the SC-CO2 extracts exhitited a higher cytotoxic effect on hepatoma cells (Huh 7) rather than on normal liver cells (Chang liver). When the freeze-dried immature, mature, senescent and abscisic leaves were subjected to SC-CO2 extraction and HPLC quantitation, squalene contents were 65, 210, 451 and 1499 μg/g powder, respectively. The results showed that the squalene content increased with an increase of leaf maturity. When the extracts were applied for antioxidative characterization by supplementation in an iron/ascorbate system with linoleic acid, in a pork-fat storage system or in a free radical scavenging system with DPPH, the extracts of leaves exhibited potent antioxidative and DPPH scavenging activities and the activities increased with an increase of leaf maturity. Squalene was not detected in the extracts of T. catappa seeds while the extracts exhibited a significant antioxidative activity. In conclusion, the SC-CO2 extracts of T. catappa leaves exerted potent antimutagenicity and antioxidative activities.
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