本研究的主要目的在進行香蘭葉 (Pandanus amaryllifolius Roxb.) 超音波萃取物抗氧化與輻射效應之 影響。實驗中利用超音波萃取技術進行香蘭葉的萃取，再以總多酚、總類黃酮、DPPH 自由基清除率、亞 鐵離子螯合等非酵素系統進行香蘭葉萃取物抗氧化能力的評估。以過氧化氫誘發氧化壓力的毒性效應測試 香蘭葉萃取物細胞內抗氧化的能力，再以 5.5 戈雷 (Gy) 的輻射劑量照射，用 MTT 分析方法測定細胞 的存活，評估香蘭葉萃取物對輻射效應之影響。研究結果顯示香蘭葉總多酚含量為 139.89±0.43 GAE mg/g， 總類黃酮含量為 44.24±0.61 RE mg/g， DPPH 與亞鐵離子螯合的 IC50 分別為 5.87±0.02mg/mL 和 15.3±0.07mg/mL。在 H2O2 對細胞傷害的實驗中，香蘭葉萃取物對於肝癌細胞(Hep G2)有顯著(p<0.05)的毒 殺作用，且細胞存活比率會隨著萃取物濃度增加而增高殺死細胞的比率。萃取液濃度分別為25、250、1000 和1500 g/mL 經過72 小時培養後，細胞存活率分別為64.7 %、 50.4%、37.5%, 和 30.6%。低濃度香蘭萃 取物對於Hep G2 細胞有輻射增敏作用，以濃度為25g/mL 的香蘭萃取物合併5.5 Gy 的輻射劑量照射，發 現其存活率由單獨以5.5 Gy 輻射劑量照射的54.58% 降至12.11%。綜合以上的結果，香蘭葉萃取物具有不 錯的抗氧化能力，並且有不錯的輻射效應影響能力，但其真正的作用機制需要做進一步的實驗探討。

The aims of this study were to evaluate the antioxidative and the influence of radiation effects of extracts of Pandanus amaryllifolius Roxb (P. amaryllifolius) by ultrasound extraction. For non-enzymatic antioxidants, several methods were used, they were the total polyphenol, total flavonoid, α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging assay, ferrous ion chelation. The cytotoxic effect of oxidative stress induced by hydrogen peroxide (H2O2) was used to evaluate the intracellular antioxidative ability of the extracts. Cells were exposed to 5.5 Gy of -ray, the surviving fraction of cells were determined by MTT method to evaluate the radiation effect of the extracts of P. amaryllifolius. The results revealed that extracts of P. amaryllifolius has a total phenolic content of 139.89±0.42 gallic acid equivalents (GAE) mg/g, total flavonoid content of 44.24±0.61 rutin equivalents (RE) mg/g. The half-inhibition concentration (IC50) of DPPH radical scavenging and ferrous metal ion chelating of the extracts of extracts of P. amaryllifolius were 5.87 and 15.3 mg/mL, respectively. There was significant (p<0.05) cytotoxic effect of extracts of P. amaryllifolius on liver hepatocellular carcinoma (HepG2), and the cell viability was decreased with the concentration of extracts of P. amaryllifolius. The cell viability was 64.7 %, 50.4%, 37.5%, and 30.6% at 25, 250, 1000 and 1500 g/mL of extracts of P. amaryllifolius incubated for 72hr. there was radioprotective effect occur in clone 9, the survival fraction was increase to 1.61 times at 1000 g/mL. There was radiosensitive effect on low concentration of extracts of P. amaryllifolius in HepG2 cell, the survival fraction was 54.58% 2.18 in irradiation control group, it decreased to 12.11%3.17 at 25 g/mL of extracts of P. amaryllifolius. The results show the extracts of P. amaryllifolius had strong antioxidative activity and the ability of influence of radiation damage, but the influence mechanism required further investigation.