摘要：以洋蔥為原料，對洋蔥多糖的提取、分離純化及抗氧化活性進行了研究。脫蛋白的最佳方法為木瓜蛋白酶-Sevag法脫蛋白；AB-8為最佳脫色樹脂，樹脂用量25 g，0.5 mL/min的速度吸附，溶液pH 5.5脫色效果最好。對洋蔥多糖提取液進行超濾實驗，應采用10×103的超濾膜。洋蔥對-OH的清除效果好，對O2--的清除效果弱，具有較強的還原能力，且隨濃度的增大還原力逐漸增強。

關鍵詞 洋蔥；多糖；提取；分離純化；抗氧化

Abstract：Onions were used as raw material in this paper, and its extraction, purification, monosaccharide and antioxidant activity were studied. The best way of deproteinization is the Papain-Sevag method; AB-8macroporous resin has the better adsorption abilities, the weight of AB-8 was 25 g. When the moving speed was 0.5 mL/min, the pH was 5.5 . Ultrafiltration experiment was used in the separation and purification of onion polysaccharide，the best was 10×103 of the membrane. The onion polysaccharides have strong scavenging effects on hydroxyl radicals, the scavenging effect on superoxide radical was not abvious. Moreover, onion polysaccharides have certain reductive capability, and its ability increased with the concentration gradually.

Keywords  Nion  Olysaccharide  Extraction  Reification  Ntioxidantactivity