木素对测量木素中残存糖分的影响

Effect of Lignin on the Measured Value of Residual Carbohydrate Content

利用超滤和有机溶剂法提纯碱木素并使用水解法和澄清法制备糖分测量的样品,对比了3,5-二硝基水杨酸(DNS)比色法和高效液相色谱(HPLC)法测定木素内残余糖分。研究结果表明:DNS法测量木素中残留糖分的含量远大于HPLC法的测量值,木素中的醛基结构是造成显色法结果偏大的主要原因。

The purified lignin were prepared by using uhrafiltration and organic solvent method, and the samples for the measurement of residual carbohydrate content were prepared by using hydrolytic and precipitation methods. 3,5-Dinitrosalicylic acid （DNS） colorimetfic and high pressure liquid chromatography （HPLC） methods were selected to determine the residual carbohydrate contents in the lignin samples. The experimental results show that the measured value of residual carbohydrate contents obtained from DNS eolorimetric methods is greater than that obtained from HPLC method. The existence of aldehyde group in the lignin is the major reason for the larger measured value.