现代环境研究室知识库

A two-step method to extract pure cellulose from tree rings is presented in this study. The method employs the reagents diglyme (diethylene glycol dimethyl ether), hydrochloric acid and sodium chlorite in a 6-h reaction using ordinary equipment. Through separation of the chemical compositions (monosaccharides) using liquid chromatography, the product of this method is shown to contain only glucose from pure cellulose. In contrast, the chemical composition of the "alpha-cellulose" extract obtained by the traditional Jayme-Wise method is primarily glucose and mannose, which may come from hemicelluloses. These results are also verified by comparing the stable carbon isotope ratio (delta C-13), yields and percentage of carbon (C%) of the product extracted by this method and "alpha-cellulose" for different tree species. The results suggest that this method is simple, rapid and appropriate for processing large numbers of small wood samples to develop tree-ring isotope series for high-resolution paleoclimatic research with softwood trees.