萌发处理对黑青稞活性成分组成及抗氧化能力的影响

Effect of germination on the composition of active ingredients and antioxidant capacity in black highland barley

为研究青稞萌发过程中活性成分和抗氧化能力的变化情况,以西藏黑青稞为原料,采用刚果红法、酶联免疫吸附法等方法测定了黑青稞萌发过程中子叶、种皮和胚根中活性成分和抗氧化能力的变化,并对活性成分和抗氧化能力进行了相关性分析。结果表明,萌发7 d与萌发3 d相比,子叶、种皮和胚根中β-葡聚糖含量整体均呈下降趋势,分别下降了24.87%、33.03%和44.90%。子叶和胚根中褪黑素含量均在第5天达到峰值,分别为(6.56±0.19)、(6.87±0.05)ng/g,种皮中褪黑素含量逐渐降低。子叶和胚根中总黄酮和总酚含量波动,种皮中总酚和总黄酮含量整体呈上升趋势,萌发7 d与萌发3 d相比,分别增加了26.35%和48.67%。种皮的抗氧化能力显著高于子叶和胚根,萌发7 d黑青稞种皮的铁离子还原能力、DPPH自由基清除能力和ABTS阳离子自由基清除能力分别为萌发前的1.82、2.50和4.02倍。相关性分析表明子叶中β-葡聚糖含量与ABTS阳离子自由基清除能力呈极显著的正相关(P<0.01);子叶、种皮和胚根中总酚含量、种皮中总黄酮含量与铁离子还原能力、DPPH自由基清除能力和ABTS阳离子自由基清除能力呈极显著的正相关(P<0.01);子叶和胚根中总黄酮含量与铁离子还原能力和DPPH自由基清除能力呈极显著的正相关(P<0.01),其他指标间呈负相关或不相关。综上,萌发处理提高了黑青稞不同组织活性成分含量和抗氧化能力,该文为黑青稞活性成分开发及利用提供了数据支撑和理论参考。

To study the changes of active ingredients and antioxidant capacity during the germination of barley,the Congo red method and enzyme-linked immunosorbent assay were used to determine the changes of active ingredients and antioxidant capacity in cotyledons,seed coats and embryo roots of black highland barley during the germination process.The correlation between the active ingredients and antioxidant capacity were explored.The results showed that the overallβ-glucan content in cotyledons,the seed coat and radicle decreased with the elongation of germination time and decreased by 24.87%,33.03%and 44.90%on the 7 d of germination compared with 3 d respectively.Melatonin content in both cotyledons and radicles peaked at(6.56±0.19)ng/g and(6.87±0.05)ng/g at 5 d,respectively,and melatonin content in seed coat gradually decreased.Total flavonoid and total phenolic contents in cotyledons and radicles fluctuated,while total phenolic and total flavonoid contents in seed coat showed an overall increasing trend which with an increasing of 26.35%and 48.67%on the 7 d of germination compared to 3 d,respectively.The antioxidant capacity of seed coat was significantly higher than that of cotyledons and radicles,and the FRAP reducing capacity,DPPH scavenging capacity and ABTS scavenging capacity of black barley seed coat on the 7 d of germination were 1.82,2.50 and 4.02 times higher than those before germination.Correlation analysis showed thatβ-glucan content in cotyledons was significantly high and positively correlated with ABTS scavenging ability(P<0.01).Total phenol content in cotyledons,the seed coat and radicle,total flavonoid content in seed coat were significant positively correlated with FRAP reducing ability,DPPH scavenging ability and ABTS scavenging ability(P<0.01).Moreover,total flavonoid content in cotyledons and radicle was significantly positive correlated with FRAP reducing ability and DPPH scavenging ability.Meanwhile,The total flavonoid content in cotyledons and embryo roots showed a significantly positive correlation with FRAP reducing ability and DPPH scavenging ability(P<0.01).In conclusion,the sprouting treatment increased the content of active ingredients and antioxidant capacity of different tissues of black barley,and this study provides data support and theoretical reference for the development and utilization of active ingredients of black highland barley.