不同品种鲜食玉米的营养成分及抗氧化活性比较

Nutritional Composition and Antioxidant Activity of Different Kinds of Fresh Edible Maize

测定6个不同鲜食玉米品种的粗脂肪、蛋白质、淀粉、还原糖和总酚含量,对脂肪酸组成进行气相色谱分析。通过比较玉米浸膏的Fe^(3+)还原力和羟自由基(·OH)、超氧阴离子(O_2-·)、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率,评价其抗氧化活性,探讨抗氧化活性与玉米总酚的相关性。结果表明,鲜食玉米含粗脂肪6.17%~13.63%、蛋白质9.57%~15.30%、淀粉58.90%~69.52%、还原糖33.51%~42.12%、总酚1.52~2.68 mg/g。迪甜6号、晋超甜1号和超甜1825的粗脂肪、蛋白质、还原糖、总酚含量较高;京科糯2000、美玉糯13和都市丽人淀粉含量较高;美玉糯13饱和脂肪酸含量较高;晋超甜1号不饱和脂肪酸含量较高。超甜1825的Fe^(3+)还原力最强,迪甜6号清除·OH、O_2-·、DPPH自由基能力较强,抗氧化活性与玉米总酚含量呈正相关。

Rough fat, protein, starch, reducing sugar and total phenol content in 6 fresh-eating maize varieties were determined. Fatty acid composition was analyzed by gas chromatography. Antioxidant activity were evaluated by compared Fe3~ restoring force and hydroxyl radical（-OH）, superoxide anion（O2-.）, 1,1-diphenyl-2-picrylhydrazyl （DPPH） radical-scavenging rate, then explored the relationship between antioxidant activity and total phenolic in maize. The results showed that fresh edible maize contained crude fat 6.17%-13.63%, protein 9.57%-15.30%, starch 58.90%-69.52%, reducing sugar 33.51%-42.12% and total phenols 1.52 mg/g - 2.68 mg/g. Among deferent fresh maize varieties, crude fat, protein, reducing sugar and total phenols in Ditian 6, Jinchaotian 1 and Chao- tian1825 maize were higher, starch in Jingkenuo2000, Meiyunuo 13 and Dushiliren maize were higher. Unsaturated fatty acid（UFA） in Jinchaotian 1 was the highest, saturated fatty acid（SFA） in Meiyunuo 13 was the highest. Fe3＋ re- storing force of Chaotian 1825 was the highest, ~ OH, O2-＇, DPPH radical-scavenging rate of Ditian 6 was the best.