铁棍山药蛋白质的分离纯化及体外抗氧化活性

Extraction, Purification and Antioxidant Activity in vitro of Protein Fractions from Dioscorea opposita Thunb. cv. Tiegun

以铁棍山药为材料,研究其蛋白质的分离纯化及体外抗氧化活性。山药粗蛋白质经DEAE-52纤维素层析柱及Sephadex G-100层析柱纯化,得到两个蛋白质组分PDOT-1和PDOT-2,经SDS-PAGE电泳,发现蛋白质分子质量分布在20、31、50kD和66kD。体外抗氧化实验表明山药粗蛋白质、PDOT-1和PDOT-2对DPPH自由基、O-2、.OH具有较明显的清除作用,并且对Fe2+具有较强的螯合作用。因此铁棍山药蛋白质具有较好的抗氧化活性,可作为潜在的抗氧化剂或抗衰老药物进行深入研究。

Crude protein extracted from Dioscorea opposita Thunb.cv.Tiegun by saturated ammonium sulfate precipitation was purified/fractionized by DEAE-52 ion exchange chromatography,and two fractions were obtained and named as PDOT-1 and PDOT-2,respectively.Further Sephadex G-100 chromatography revealed that both fractions were composed of a single component.The non-reducing SDS-PAGE pattern of PDOT-1 displayed three protein bands with a molecular mass of respec-tively 20,31 kD and 50 kD and only one 66 kD protein band was observed in that of PDOT-2.It was found that the crude protein,PDOT-1 and PDOT-2 had obvious radical scavenging activities on DPPH,superoxide anion and hydroxyl free radicals as well as strong ferrous ion-chelating capacity.We concluded that proteins from Dioscorea opposita Thunb.cv.Tiegun have antioxidant activity and deserve to be studied in depth as a potential anoxidant or anti-aging drug.