摘要:
The changes in the release and antioxidant activity of bioactive components from six kinds of black foods (black rice,black tartary buckwheat,rye,black soybean,black gram,black millet) during in vitro simulated gastrointestinal digestion process were investigated.The results showed that after 2 h simulated gastric digestion,the highest release rates of polyphenols and flavonoids were observed from black millet and black soybean,reaching 28% and 41%,respectively.On the other hand,rye and black gram showed the highest release rates of both compound classes (113% and 52%) after another 2 h of simulated intestinal digestion.Furthermore,black soybean,black millet and black rice exhibited the highest increase in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (114%),ferric ion reducing antioxidant power (FRAP) (31%) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity (28%) during simulated gastric digestion,while the highest increase in DPPH radical scavenging activity (161%),FRAP activity (124%) and ABTS radical scavenging activity (199%) were observed for black tartary buckwheat,black millet and black rice during simulated intestinal digestion.Simulated digestion of six kinds of black foods with pepsin,tyrisin and bile significantly enhanced the release of polyphenols and flavonoids and antioxidant activity.In particular,black rice possessed the strongest antioxidant activity both before and after digestion;after gastrointestinal digestion,its antioxidant activity was determined to 4 531.79 μmol Trolox/100 g md in DPPH radical scavenging assay,3 729.69 μmol Trolox/100 g md in FRAP assay,and 3 727.14 μmol Trolox/100 g md in ABTS radical scavenging assay,200%,171% and 383% higher than those before digestion,respectively.Black rice is therefore a promising black food.%通过体外模拟胃、肠消化法考察6种黑色食品(黑米、黑苦荞、黑麦、黑豆、黑绿豆、黑小米)在胃、肠道消化过程中抗氧化成分及其活性变化规律.结果发现,通过模拟胃消化2h后,多酚和黄酮释放增长比例最高的分别是黑小米和黑豆,分别增长28%和41%,进一步通过模拟肠消化2h后,多酚和黄酮释放增长比例最高的分别是黑麦和黑绿豆,分别增长113%和52%.1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力、亚铁还原能力(ferric ion reducing antioxidant power,FRAP)和2’-联氨-双-3-乙基苯并噻唑啉-6-磺酸(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid,ABTS)自由基清除能力在模拟胃消化阶段的增长比例最高的分别是黑豆(114%)、黑绿豆(31%)和黑米(28%),在模拟肠消化阶段增长比例最高的分别是黑苦荞(161%)、黑小米(124%)和黑米(199%).通过模拟胃蛋白酶、胰酶和胆汁等消化作用后能显著提升黑色食品的黄酮、多酚释放量和抗氧化活性(P<0.05),尤其是黑米,在消化前后均表现出最强的抗氧化活性,通过胃、肠消化后,其DPPH自由基清除能力、FRAP和ABTS+·清除能力分别为4 531.79、3 729.69 μmol Trolox/100 g md和3 727.14μmol Trolox/100 g md,分别较未消化时增长了200%、171%和383%,是较有应用前景的一种黑色食品.