豆渣膳食纤维的结构表征及其抗氧化性研究

Structural Characterization and Antioxidant Activity of Soybean Dregs Dietary Fiber

采用扫描电镜、红外光谱、热重及化学分析等方法对豆渣膳食纤维(soybean dregs dietary fiber,SDF)的结构进行表征,对其抗氧化性及其对维生素C(VC)抗氧化活性的影响进行了探讨。研究发现,SDF中不溶性膳食纤维含量占总膳食纤维含量的92%左右。SDF颗粒形貌各异,结构紧密,内部由纤维素类物质形成支撑主体,热力学稳定。SDF具有良好的羟自由基(·OH)清除能力,且呈量-效关系,但DPPH·清除能力很弱。SDF-VC复合物清除·OH的能力表现为简单的加和作用,但其在DPPH·体系中则表现出良好的协同增效作用,能有效抑制VC的降解。

The structure of soybean dregs dietary fiber （SDF） was investigated by SEM, IR, TGA and chemical methods. Results showed that insoluble dietary fiber accounted for 92% of total dietary fiber in SDF. Particles of SDF with various sizes, shapes and intensive structure were supported mainly by cellulose inside, and SDF was thermodynamically stable. SDF exhibited good scavenging activity of hydroxyl radical, and it was increased with the concentration increasing. But its scavenging activity of DPPH was very low. The effect of SDF on the antioxidant activity of vitamin C （Vc） was also investigated, there was additive effect between SDF and Vc on scavenging activity of hydroxyl radical. But there was good synergistic effect between them on scavenging activity of DPPH and SDF effectively reduced VC degradation.