Rapid Determination of Sugars in Hemicellulose Extraction Liquor by Dual-Wavelength Spectrophotometry
CHI Cong-cong1,ZHANG Zeng1*,CHAI Xin-sheng1, 2,GE Wei-wei1
1. State Key Laboratory of Pulp & Paper Engineering, South China University of Technology, Guangzhou 510640, China 2. Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta GA 30332, USA
Abstract:The traditional Douglas colorimetric method (phloroglucinol–glacial acetic acid colorimetry) could only be used to measure all forms of five-carbon sugars, including mono-, oligo- and poly- saccharides. Relative improvement is done on this method to achieve simultaneous deter mination of pentosan, hexosan and their monosaccharides, by the dual-wavelength method. Results indicate that 425 nm is the equal molar absorption wavelength of pentose and hexose, while 553 nm is the maximum absorption wavelength of pentoses. So the calculating formula has been greatly simplified based on the absorbance at 425 and 553 nm. The research results of interfering substances in the extraction liquor show that the lignin and glucuronic acid has no significant influence on the deter mination of pentoses or hexoses. It is concluded that this improved method has high precision and accuracy, and its recovery range is from 97.4% to 101.9%. Therefore, as a simple and rapid method, it is quite appropriate for measuring mixed sugars of pentoses and hexoses in the extraction liquor from hardwood or gra minaceous plant.
[1] van Heiningen A. Pulp & Paper Canada, 2006, 107(6): 38. [2] Amidon T E. Pulp & Paper Canada, 2006, 107(6): 47. [3] Miller G L. Anal. Chem., 1959, 31: 426. [4] Scott T A, Melvin E H. Anal. Chem., 1953, 25: 1656. [5] Dubois M, Gilles K A, Hamilton J K, et al. Anal. Chem., 1956, 28: 350. [6] Douglas S G. Food Chem., 1981, 7: 139. [7] LI Xiao-hua, HE Lan-fang, CHANG Feng-mei, et al(李筱华, 何兰芳, 常凤眉, 等). Chinese Journal of Chromatography (色谱), 1987, 5(1): 4. [8] Cheetham N W H, Sirimanne P,Day W R. J. Chromatogr., 1981, 207: 439. [9] LIANG Li-na, ZHANG Ping, CAI Ya-qi,et al(梁立娜,张 萍,蔡亚岐,等). Chinese Journal of Analytical Chemistry(分析化学), 2006, 34(10): 1371. [10] Lundguist K,Kirk T K. Tappi J., 1980, 63(1): 80. [11] CHEN Jia-xiang, YU Jia-luan(陈嘉翔,余家鸾). Research Methods for the Chemical Structure of Plant Fibers(植物纤维化学结构的研究方法). Guangzhou: Publishing Company of South China University of Technology(广州:华南理工大学出版社), 1989. 43.