Meng Shao , Yue Yang , Hao Liu , Hui Zhou , Yuanyuan Sun , Xia Zhao , Guangli Yu , Youjing Lv , Quancai Li
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引用次数: 0
Abstract
This study presents a carboxyl-conversing titration method for determining the uronic acid content of alginate oligosaccharide (AOS). All C6 carboxyl groups on the monosaccharide residues of AOS were initially converted into carboxylates, which were subsequently transformed into carbonates through carbonization and incineration. Quantification was finally done through acid titration. The AOS content, which was represented by the amount of monosaccharide residues (ManA and GulA residues) in AOS sample, was calculated based on the stoichiometric relationship between the C6 carboxyl group and monosaccharide residue. To evaluate its performance, the carboxyl-conversing titration method was compared with the sulfuric acid-carbazole method and 1-phenyl-3-methyl-5-pyrazolone (PMP) pre-column derivatization high performance liquid chromatography (PMP-HPLC) method. The content of the uronic acid in AOS sample were detected 96.24 % ± 0.42 % using the carboxyl-conversing titration method, 186.85 ± 0.49 % (ManA/GulA = 1/1 as the reference standard) using the sulfuric acid-carbazole method, and 3.00 ± 0.08 % using the PMP-HPLC method. The carboxyl-conversing titration method demonstrated the highest accuracy of the content value. The validation of this method was also confirmed in the terms of specificity, limits of detection and quantification, recovery, repeatability, intermediate precision and durability. Compared to the sulfuric acid-carbazole and PMP-HPLC methods, the carboxyl-conversing titration method was proved easy to operate, reliable, and independent of reference standards. This innovative method offers a promising solution for accurately determining AOS content in laboratory and industrial settings.
期刊介绍:
Carbohydrate Research publishes reports of original research in the following areas of carbohydrate science: action of enzymes, analytical chemistry, biochemistry (biosynthesis, degradation, structural and functional biochemistry, conformation, molecular recognition, enzyme mechanisms, carbohydrate-processing enzymes, including glycosidases and glycosyltransferases), chemical synthesis, isolation of natural products, physicochemical studies, reactions and their mechanisms, the study of structures and stereochemistry, and technological aspects.
Papers on polysaccharides should have a "molecular" component; that is a paper on new or modified polysaccharides should include structural information and characterization in addition to the usual studies of rheological properties and the like. A paper on a new, naturally occurring polysaccharide should include structural information, defining monosaccharide components and linkage sequence.
Papers devoted wholly or partly to X-ray crystallographic studies, or to computational aspects (molecular mechanics or molecular orbital calculations, simulations via molecular dynamics), will be considered if they meet certain criteria. For computational papers the requirements are that the methods used be specified in sufficient detail to permit replication of the results, and that the conclusions be shown to have relevance to experimental observations - the authors'' own data or data from the literature. Specific directions for the presentation of X-ray data are given below under Results and "discussion".