- 學位論文
奈米/次微米山藥對人類皮膚細胞膠原蛋白生合成與雌激素活性表現之影響
Effects of nano/submicron yam on secretion of collagen and expression of estrogenic activity
摘要
山藥為薯蕷屬多年生蔓生性根莖類植物，富含生理活性成分（如固醇類皂素與植物固醇），為合成部份固醇類荷爾蒙的重要前驅物。山藥皮是廢棄物，卻有高量的薯蕷皂配基(diosgenin)，可調節皮膚老化現象，將其製成奈米/次微米懸浮液，不僅可增加活性成分的吸收與利用，同時減少廢棄物的產生。 以介質研磨方法製備奈米/次微米山藥懸浮液，山藥之粒數平均粒徑小於100 nm，以掃描式電子顯微鏡確認奈米粒子的存在。山藥未去皮，可大幅提升山藥中膳食纖維與有效成分(diosgenin、stigmasterol與beta-sitosterol)之含量。奈米/次微米山藥經過基因毒性試驗，證實其對S. typhimurium TA98及TA100不具毒性，也不具有致突變性，對於添加4-NQO致突變劑誘導致突變之菌株也具有抗致突變效果。利用奈米/次微米山藥處理皮膚纖維母細胞WS1，發現其膠原蛋白分泌量增加，奈米/次微米山藥可促進細胞分泌hTGF beta與EGF，促進膠原蛋白的分泌，並減少MMP-1分泌，減少膠原蛋白分解。奈米/次微米山藥可被REA酵母菌利用，影響雌激素活性之表現。奈米/次微米磨山藥之雌激素當量為4.87×10-8 micro g/g乾重，為細碎山藥之1.22倍，且可造成MCF-7細胞凋亡與壞死，具有抑制乳癌細胞MCF-7與子宮內膜癌細胞Ishikawa增生之功效。
並列摘要
Nano/submicrometer-scaled yam particles have been prepared by using media-milling. The particle size of media-milled yam was determined by the laser light scattering method and was confirmed by scanning electron microscopy. Influences of nano/submicron yam on skin fibroblast cells (WS1) were evaluated. The size reduction did not significantly alter the proximate composition, and the presence of nanoparticles was not toxic to WS1 cells. Nano/submicron yam does not have mutagenicity as well but exhibits antimutagenicity ability. The contents of bioactive compounds (diosgenin, stigmasterol and β-sitosterol) were significantly increased by media-milling, which enhanced the secretion of hTGF-β and inhibited the formation of MMP-1. Thus, the collagen secretion from WS1 was significantly increased by size reduction. Diosgenin was employed as a positive control. Nevertheless, media-milled yam exhibited greater effects on WS1 cells than diosgenin. It appeared that both diosgenin and size reduction were helpful for enhancing the secretion of collagen by WS1 cells. In addition, the irritancy of yam was eliminated by media-milling. The effect of nano/submicron yam on estrogenic activity of REA yeast was also discussed. Nano/submicron yam inhibited proliferation of human breast cancer cell MCF-7 and human endometrial adenocarcinoma Ishikawa cells though increasing cell apoptosis and necrosis. In conclusion, reducing size into nano/submicron scale of yam retained diosgenin and fiber for functional food/neutricosmetics and minimized the quantity of waste.