Comparisons of in vitro Antioxidant Activities of Storage Proteins in Tuber of Two Dioscorea Species

兩品種山藥塊莖儲藏性蛋白質體外抗氧化活性之研究

劉玉華(Yuh-Hwa Liu) ； 梁弘人(Hong-Jen Liang) ； 鄭惠川(Huey-Chuan Cheng) ； 劉燕雯(Yen-Wenn Liu) ； 侯文琪(Wen-Chi Hou)

《Botanical Studies》 47卷3期 (2006/07) Pp. 231-237

摘要

兩品種山藥《台農一號與日本山藥》塊莖儲藏性蛋白質dioscorin經由DE-52離子交換層析法純化。經由一系列體外抗氧化實驗，包括清除DPPH與氫氧自由基，還原能力，抗脂質過氧化能力，保護去氧核糖核酸傷害能力，及抑制peroxynitrite氧化dihydrorhodamine 123能力。結果顯示，兩品種山藥dioscorin具有不同的抗氧化能力，即使100℃加熱五分鐘也仍具有不同的清除DPPH與氫氧自由基的能力。以胃蛋白酶水解台農一號dioscorin不同時間之水解產物也具有清除DPPH自由基的能力。以Sephadex G-50(F)膠濾層析進行分離並進行DPPH自由基清除實驗，結果顯示小分子水解產物也具有抗氧化能力。

關鍵字

抗氧化 ； 儲藏性蛋白質 ； 胃蛋白酶水解物 ； 山藥

並列摘要

Dioscorin was purified by DE-52 ion exchange chromatography from two yam species, Dioscorea alata L. cv. Tainong 1 (TN1) and Dioscorea batatas Decne (imported from Japan, JP). By different in vitro antioxidant tests, including DPPH radical and hydroxyl radical scavenging activity assay, a reducing power test, an anti-lipid peroxidation test, DNA damage protection, and inhibition of dihydrorhodamine 123 oxidation by peroxynitrite, it was shown that dioscorins from the two species exhibited different scavenging activities against DPPH and hydroxyl radicals, even after heating 100℃ for 5min. Dioscorins from TN1 were hydrolyzed by pepsin for different durations and the peptic hydrolysates exhibited DPPH radical scavenging activities. Peptic hydrolysates separated by Sephadex G-50(F) gel filtration were tested for anti-DPPH radical activity. Results showed that fractions of smaller molecular weight still have antioxidant activities.

並列關鍵字

Antioxidant ； Dioscorin ； Peptic hydrolysates ； Storage protein ； Yam