奈米/次微米化枸杞懸浮液抗氧化性及安全性之探討

Abstract

本研究為探討奈米/次微米枸杞懸浮液之製備、抗氧化能力與安全性。將5 % 枸杞以介質研磨方式降解至奈米/次微米等級，粒徑分析儀測量粒徑分佈得知，經過90分鐘研磨後，體積平均粒徑減少為15.3 μm，粒數平均粒徑減少為102 nm，離心後 (10000 ×g, 10min) 上清液之體積平均粒徑為587.5 nm。同時以穿透式電子顯微鏡證實確實有奈米/次微米顆粒之存在。比較其與熱水、冷水及酒精萃出物之抗氧化能力， 發現奈米/次微米枸杞懸浮液在還原力、螯合亞鐵離子 (EC50=2.11 mg/mL) 與總抗氧化能力 (TEAC value=0.028mM) 均優於熱水、冷水及酒精萃出物。抗氧化成分分析得知，奈米/次微米枸杞懸浮液中，總酚類 (19.3 mg/g) 、總類胡蘿蔔素 (1.27 mg/g) 及β-類胡蘿蔔素 (0.23 mg/g) 之含量均高於熱水、冷水及酒精萃出物，類黃酮 (4.01 mg/g) 含量高於熱水、冷水萃出物。以沙門氏逆突變試驗 (Ames test) TA98、TA100菌系評估奈米/次微米枸杞懸浮液之安全性，結果得知奈米/次微米枸杞懸浮液對TA98及TA100菌株不具致突變性。

This study discussed the preparation, antioxidant activities, and safety of nano/submicron Lycium spp.. Media milling was used to reduce the material to nano/submicron scale. After milling for 90min，the volume mean diameter decreased to 15.3μm and the number mean diameter decreased to 102 nm. The volume mean diameter after centrifugation (10000 ×g, 10min) was about 587.5 nm. Transmission electron microscopic (TEM) photographs also proved the existence of nano/submicron scale particle. The reducing power, ferrous chelating effect (EC50=2.11 mg/mL) and the Trolox equivalent antioxidant capacity (TEAC) assay (TEAC value=0.028mM) of milled product is higher than that of hot, cold water and 95% ethanol extract. The total polyphenol (19.3 mg/g) , total carotenoids (1.27 mg/g) and β-carotene (0.23 mg/g) contents in milled product was higher than that in the extract by hot, cold water and 95% ethanol. The flavonoids (4.01 mg/g) in milled product was higher than that in the extract by hot, cold water. From Ames test, nano/submicron Lycium suspension in this study had no mutagenic effect to the Samonella typhimurium TA 98 and TA100.