不同品种裸燕麦活性成分及抗氧化性研究

Analysis of Active Components and Antioxidant Property in Different Naked Oat(Avena nuda L.)Varieties

为研究裸燕麦活性成分组成及其抗氧化活性,以24个裸燕麦品种为研究对象,对比其多糖类(膳食纤维、β-葡聚糖和低聚糖)含量、脂肪酸组成、酚酸组分含量、总黄酮含量及抗氧化活性,分析抗氧化能力与多酚类物质含量的相关性。结果表明,大部分品种裸燕麦的多糖类物质含量差异显著(P<0.05);不饱和脂肪酸占总脂肪酸的比例为76.62%~80.96%,其中亚油酸占不饱和脂肪酸的比例最高(37.64%~47.12%),其次为油酸(28.33%~39.89%);总酚和总黄酮含量分别为865~1 367和234~502μg·g^(-1);阿魏酸、咖啡酸、芥子酸和对香豆酸是裸燕麦酚酸的主要组分,含量分别为521~881、82~152、55~138和43~121μg·g^(-1),分别占总酚含量的54.4%~64.5%、7.4%~14.4%、5.3%~12.0%和4.8%~11.2%;大部分品种裸燕麦的多酚类物质对1,1-二苯基-2-苦肼基自由基(DPPH·)和2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐自由基(ABTS·+)的清除率,及铁离子还原能力(FRAP)存在显著差异(P<0.05),其中坝莜3号的多酚类提取物对DPPH·和ABTS·+的清除率和FRAP值显著高于其他品种(P<0.05),分别为46.8%、88.7%和927 mmol·g^(-1);ABTS·+清除率与总黄酮含量呈极显著正相关(P<0.01);FRAP与总酚、总黄酮和阿魏酸含量呈显著正相关(P<0.05)。本研究可为优质燕麦高抗氧化品种选育和杂交组配提供理论依据,也可为燕麦食品开发提供实践基础。

To study the active components and antioxidant property in different naked oat(Avena nuda L.)varieties,the polysaccharide contents(including dietary fiber,β-glucan and oligosaccharide),fatty acid composition,phenolic acid contents,total flavonol contents and antioxidant activities of 24 naked oat cultivars were determined.In addition,the differences of active components and antioxidant activities among these cultivars were also compared.As the results,significant differences were found in polysaccharide contents among different varieties of naked oat(P<0.05).The proportion of unsaturated fatty acids in total fatty acids ranged from 76.62%-80.96%,among which linoleic acid accounted for the highest(37.64%-47.12%),followed by oleic acid(28.33%-39.89%).The contents of total phenols and flavonoids in naked oat ranged from 865-1367 and 234-502μg·g-1,respectively.The contents of ferulic acid,caffeic acid,sinapic acid and p-coumaric acid ranged from 521-881,82-152,55-138 and 43-121μg·g-1,respectively.Ferulic acid,caffeic acid,sinapic acid and p-coumaric acid accounted for 54.4%-64.5%,7.4%-14.4%,5.3%-12.0%and 4.8%-11.2%,respectively,which were the main components of naked oat phenolic acids.There were significant differences in the scavenging ability of 1,1-Diphenyl-2-picrylhydrazyl radical(DPPH·)and[2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt radical](ABTS·+)free radicals and ferric ion reducing antioxidant power(FRAP)among different varieties of naked oat polyphenols(P<0.05).Compared to other varieties,the polyphenol extracted from the Bayou No.3 showed significantly higher scavenging abilities for DPPH·and ABTS·+free radicals,as well as FRAP,with the values of 46.8%,88.7%and 927 mmol·g^(-1),respectively.The free radical scavenging rate of ABTS·+was positively correlated with the content of total flavonoids(P<0.01),and FRAP was positively correlated with the contents of total phenols,flavonoids and ferulic acid(P<0.05).This study provides a theoretical basis for breeding high-quality oat varieties with high antioxidant properties and hybrid combinations,and also offers a practical basis for the development of oat-based foods.