本研究針對本實驗室合成之酯化原兒茶酸衍生物(編號01~07)、醯胺化原兒茶酸衍生物(編號11~13)及酯化咖啡酸衍生物(編號08~10)、醯胺化咖啡酸衍生物(編號14~16)，利用進行清除2,2-diphenyl-1-picrylhydrazyl (DPPH)自由基能力測定、超微弱冷光技術(BJL)評估過氧化氫自由基抑制率、trolox equivalent antioxidant capacity (TEAC)試驗、Liposome 脂質過氧化能力、清除含氮NO自由基能力測定、暸解其衍生物是否能保護pUC119 DNA、λ -Hind Ⅲ Marker DNA避免自由基誘發損傷之效應評估、抑制酪胺酸酶活性測試，探討其衍生物在化妝品上的應用價值。
結果顯示原兒茶酸與咖啡酸其酯化合成之衍生物比醯胺化衍生物具有較佳抗氧化活性，其中以Compound -2( Ethyl 3,4-dihydroxy benzoate )清除DPPH、ABTS＋．陽離子、NO自由基能力及保護pUC119 DNA、λ -Hind Ⅲ Marker DNA避免自由基誘發損傷之效應最佳。針對Liposome 脂質過氧化能力實驗中，咖啡酸衍生物顯示較佳之活性。 This research utilizes the method of organic synthesis to the alkyl ester esterification derivatives of protocatechuic (No. 1 ~ 7)、the amidation derivatives of protocatechuic (No. 11 ~ 13) and the alkyl ester esterification derivatives of caffeic(No. 8 ~ 10)、the amidation derivatives of caffeic(No. 14 ~ 16). Through the way of testing on DPPH antioxidant capability, inhibit capability on the vitality of hydrogen peroxide and Trolox Equivalent Antioxidant Capacity,the effect on liposome assay , tests on NO antioxidant capability、the protective effects on the free radicals induced pUC119 DNA and λ -Hind Ⅲ Marker DNA , inhibittiv capability on the vitality of tyrosinase，their practical value in cosmetics will be further discussed.
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The result shows that the alkyl ester esterification derivatives of protocatechuic and caffeic have the better effect on the antioxidant capability. than the amidation derivatives of protocatechuic and caffeic. The experiment on DPPH antioxidant capability, inhibittiv and capability on the vitality of hydrogen peroxide ,we test on Trolox Equivalent Antioxidant Capacity , NO antioxidant capability、the protective effects on the free radicals induced pUC119 DNA and λ -Hind Ⅲ Marker DNA and inhibit capability on the vitality of tyrosinase shows that it is found that the effect of the Compound -2( Ethyl 3,4-dihydroxy benzoate ) is the best . The experiment on inhibitive capability on liposome assay shows that it is found that the effect of he caffeic acid is the best 。
