光质和光周期对大豆芽苗菜生长及总酚类物质含量的影响

Effects of Light Quality and Photoperiod on Growth and Total Phenolics Content of Soybean Sprouts

采用发光二极管(light emitting diode,LED)精确调制光谱能量分布,研究不同光质和光周期对大豆芽苗菜生长、总酚类物质含量及DPPH自由基清除能力的影响。光质试验结果表明:紫外光(UV-B)处理显著降低了大豆芽苗菜下胚轴长及可食率,且有利于植株水分积累;各光质处理均显著提高了下胚轴中总酚类物质含量,其中UV-B处理含量最高,显著高于黑暗培养和其他光质处理;UV-B处理子叶和下胚轴中DPPH自由基清除能力最强,均显著高于黑暗培养。光周期试验结果表明:UV-B8h·d-1处理大豆芽苗菜根长最长,下胚轴长最短;UV-B8h·d-1和12h·d-1处理下胚轴中总酚物质含量和DPPH自由基清除能力且均显著高于黑暗培养和其他光处理,其中8h·d-1光周期处理比12h·d-1效果更好。总体而言,8h·d-1的UV-B处理最有利于大豆芽苗菜下胚轴中总酚类物质积累和DPPH自由基清除能力的提高。

Light emitting diode（LED）was applied to accurately modulate light spectral energy distribution. The effects of light quality and photoperiod on the growth,total phenolics content and DPPH scavenging activity of soybean（Glycine max）sprouts were studied.The results of light quality test indicated that hypocotyl length and edible rate were significantly decreased by UV-B,which was favorable for water accumulation in plant.Every light treatment significantly increased the content of total phenolics in hypocotyls.The total phenolics content reached the max under UV-B treatment,and was much higher than that in the darkness and other light treatment. Under UV-B treatment,the DPPH scavenging activity in hypocotyls and cotyledon of soybean sprouts reached the max,and was significantly higher than that of the darkness.The photoperiod test showed that the root length reached the max and the hypocotyl length reached the min when the photoperiod was 8 h·d-1 under UV-B.The total phenolics content and DPPH scavenging activity were significantly decreased by 8 h·d-1,12 h·d-1 UV-B treatment,and were much higher than that in the darkness and other light treatment.Overall,8 h·d-1 UV-B treatment was more beneficial for the the total phenolics content and the DPPH scavenging activity of soybean sprouts.