本研究旨在探討兩種酚酸類化合物的抗氧化能力與作用在類造骨細胞的生物效應，阿魏酸與咖啡酸為具自由基清除能力的抗氧化劑，可抑制細胞的氧化損傷，而氧化壓力對於骨折的癒合與骨組織的發炎與病變均具重要性。本研究以143b 類造骨細胞進行兩種酚酸類化合物的抗氧化效應，在H2O2 誘發的氧化壓力下對類造骨細胞的生長進行探討。研究分兩個部分:1.試管內評估阿魏酸及咖啡酸的抗氧化效力，包括DPPH 自由基的清除、亞鐵離子的螯合反應、總還原力之測定;2.以MTT assay 分析單獨處理阿魏酸及咖啡酸對類骨細胞143b 細胞生長的影響，與對H2O2 誘發143b 細胞損傷的保護能力。結果顯示抗氧化能力方面，阿魏酸及咖啡酸在清除DPPH 自由基IC50 濃度分別為100、6.25μM，其與亞鐵離子皆無螯合之能力；阿魏酸、咖啡酸與標準抗氧化劑BHT 的總還原力在50μM 的濃度下分別為40.57%、50.87%、39.56%。在類造骨細胞生長實驗顯示，阿魏酸與咖啡酸抗氧化壓力傷害在25、50、100μM 時，相對於對照組(100%)分別為101.1%、100.6%、83.2%與114.1%、104.8%、75.1%，顯示咖啡酸比阿魏酸在25μM 濃度下有較高的細胞氧化損傷保護能力，而在高濃度時兩者都失去保護細胞的效果。

This study evaluated the antioxidative activities of two phenolic acids, ferulic acid and caffeic acid, and their biological effects on the 143b osteoblast-like cell line. Ferulic acid and caffeic acid, with antioxidative capabilities and as a free radicals scavenger, play an important role on protection of cellular oxidative injury. Oxidative stress could be the key factor for bone fracture healing, regional inflammation or tissue lesions. We analyzed the growth rate of 143b cells, treated by ferulic acid or caffeic acid, under cellular oxidative stress induced by hydrogen peroxide. The study was divided into two parts: (1) ferulic acid or caffeic acid were evaluated their in vitro chemical effects including DPPH radical scavenging, ferrous ions chelating, and total reducing abilities; (2) we also analyzed the growth rate of 143b cells treated by hydrogen peroxide and the same treatment but under ferulic acid or caffeic acid protection. The 50% radical scavenging inhibitory concentration (IC50) of ferulic acid and caffeic acid are 100 and 6.25 μM, respectively. We also find no ferrous ions chelating tendency of the above two phenolic acids. Under the concentration of 50 μM, total reducing capabilities of ferulic acid, caffeic acid and standard anti-oxidant compound BHT (dibutylhydroxytoluene) are 40.57%, 50.87%, 39.56%, respectively. The survival rate of 143b cells, respectively treated with 25, 50, 100μM ferulic acid or caffeic acid, are of 101.1%, 100.6%, 83.2% and 114.1%, 104.8%, 75.1%, respectively. Comparison of ferulic acid and caffeic acid, we found 25μM caffeic acid had slightly higher cellular protection against hydrogen peroxide induced oxidative injury than ferulic acid, and both of them lost the effect at high concentrations.