کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1389667 | 982908 | 2008 | 5 صفحه PDF | دانلود رایگان |
Four exopolysaccharides (EPS) obtained from Botryosphaeria rhodina strains isolated from rotting tropical fruit (graviola, mango, pinha, and orange) grown on sucrose were purified on Sepharose CL-4B. Total acid hydrolysis of each EPS yielded only glucose. Data from methylation analysis and 13C NMR spectroscopy indicated that the EPS from the graviola isolate consisted of a main chain of glucopyranosyl (1→3) linkages substituted at O-6 as shown in the putative structure below:Figure optionsDownload as PowerPoint slideThe EPS of the other fungal isolates consisted of a linear chain of (1→6)-linked glucopyranosyl residues of the following structure:Figure optionsDownload as PowerPoint slideFTIR spectra showed one band at 891 cm−1, and 13C NMR spectroscopy showed that all glucosidic linkages were of the β-configuration. Dye-inclusion studies with Congo Red indicated that each EPS existed in a triple-helix conformational state. β-(1→6)-d-Glucans produced as exocellular polysaccharides by fungi are uncommon.
Putative structure of β-(1→3,1→6)-d-glucan Structure of β-(1→6)-d-glucanFigure optionsDownload as PowerPoint slide
Journal: Carbohydrate Research - Volume 343, Issue 14, 22 September 2008, Pages 2481–2485