%0 Journal Article %1 STOKKE1993 %A STOKKE, B. T. %A SMIDSROD, O. %A ZANETTI, F. %A STRAND, W. %A SKJAKBRAEK, G. %C THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB %D 1993 %I ELSEVIER SCI LTD %J Carbohydr. Polym. %K ;; [ISI:] conformations; model sequence; %N 1 %P 39 -- 46 %T DISTRIBUTION OF URONATE RESIDUES IN ALGINATE CHAINS IN RELATION TO ALGINATE GELLING PROPERTIES .2. ENRICHMENT OF BETA-D-MANNURONIC ACID AND DEPLETION OF ALPHA-L-GULURONIC ACID IN SOL FRACTION %V 21 %X Alginate, a copolymer comprised of beta-D-mannuronic and alpha-L-guluronic acid isolated from seaweeds and extruded by certain bacteria, forms a gel in combination with several divalent cations. Polymer chains leaching out at 7-degrees-C, 24-degrees-C and 50-degrees-C from Ca-, and Sr-alginate gel beads were found to be depleted in alpha-L-guluronic acid and enriched in beta-D-mannuronic acid compared to the starting material. For Sr gels. leached material is found to be almost devoid of alpha-L-guluronic acid triplets for the Sr gels, and a significant reduction in such triplets compared to the starting material was observed for the polymers leached from the Ca-gels. The leached material was also found to comprise the low-molecular-weight tail of the starting material molecular weight distribution, the truncation towards lower molecular weight was larger for the more block-like alginate. The chemical composition of the leaching out from Sr-gels and Ca-gels suggests that 3 and 8 +/- 2 contiguous alpha-L-guluronic acid residues are required to form stable junction zones for Sr- and Ca-induced gelation respectively.

@article{STOKKE1993, __markedentry = {[phpts:6]}, abstract = {Alginate, a copolymer comprised of beta-D-mannuronic and alpha-L-guluronic acid isolated from seaweeds and extruded by certain bacteria, forms a gel in combination with several divalent cations. Polymer chains leaching out at 7-degrees-C, 24-degrees-C and 50-degrees-C from Ca-, and Sr-alginate gel beads were found to be depleted in alpha-L-guluronic acid and enriched in beta-D-mannuronic acid compared to the starting material. For Sr gels. leached material is found to be almost devoid of alpha-L-guluronic acid triplets for the Sr gels, and a significant reduction in such triplets compared to the starting material was observed for the polymers leached from the Ca-gels. The leached material was also found to comprise the low-molecular-weight tail of the starting material molecular weight distribution, the truncation towards lower molecular weight was larger for the more block-like alginate. The chemical composition of the leaching out from Sr-gels and Ca-gels suggests that 3 and 8 +/- 2 contiguous alpha-L-guluronic acid residues are required to form stable junction zones for Sr- and Ca-induced gelation respectively.}, added-at = {2011-11-04T13:47:04.000+0100}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB}, author = {STOKKE, B. T. and SMIDSROD, O. and ZANETTI, F. and STRAND, W. and SKJAKBRAEK, G.}, authoraddress = {LBT,POLY BIOS RES CTR,I-34012 TRIESTE,ITALY. ; UNIV TRONDHEIM,DEPT BIOTECHNOL,NORWEGIAN BIOPOLYMER LAB,N-7034 TRONDHEIM,NORWAY.}, biburl = {https://www.bibsonomy.org/bibtex/2c2588bb310544172a12fc18d0e529081/pawelsikorski}, citedref = {CESARO A, 1982, THERM ANAL, V2, P815 ; DUBOIS M, 1956, ANAL CHEM, V28, P350 ; DURAND D, 1990, PHYSICAL NETWORKS PO, P283 ; GRANT GT, 1973, FEBS LETT, V32, P195 ; GRASDALEN H, 1981, CARBOHYD RES, V89, P179 ; GRASDALEN H, 1983, CARBOHYD RES, V118, P255 ; HAUG A, 1970, ACTA CHEM SCAND, V24, P843 ; ILIOPOULOS I, 1988, J POLYM SCI PP, V26, P2093 ; MARTINSEN A, 1989, BIOTECHNOL BIOENG, V33, P79 ; MARTINSEN A, 1991, CARBOHYD POLYM, V15, P171 ; POWELL DA, 1982, J MOL BIOL, V155, P517 ; SMIDSROD O, 1990, TRENDS BIOTECHNOL, V8, P71 ; SOONSHIONG P, 1992, TRANSPLANTATION, V54, P769 ; STOKKE BT, 1991, MACROMOLECULES, V24, P4637 ; THOM D, 1982, CARBOHYD RES, V100, P29}, interhash = {94fcc2891556c06e0ddbf9c77edbf938}, intrahash = {c2588bb310544172a12fc18d0e529081}, isifile-dt = {Article}, isifile-ga = {LQ296}, isifile-j9 = {CARBOHYD POLYM}, isifile-nr = {15}, isifile-pi = {OXFORD}, isifile-rp = {STOKKE, BT, UNIV TRONDHEIM,DEPT PHYS,NORWEGIAN BIOPOLYMER LAB,N-7034 ; TRONDHEIM,NORWAY.}, isifile-sc = {Chemistry, Applied; Chemistry, Organic; Polymer Science}, isifile-tc = {16}, issn = {0144-8617}, journal = {Carbohydr. Polym.}, keywords = {;; [ISI:] conformations; model sequence;}, language = {English}, number = 1, owner = {phpts}, pages = {39 -- 46}, publisher = {ELSEVIER SCI LTD}, size = {8 p.}, sourceid = {ISI:A1993LQ29600007}, timestamp = {2011-11-04T13:47:25.000+0100}, title = {DISTRIBUTION OF URONATE RESIDUES IN ALGINATE CHAINS IN RELATION TO ALGINATE GELLING PROPERTIES .2. ENRICHMENT OF BETA-D-MANNURONIC ACID AND DEPLETION OF ALPHA-L-GULURONIC ACID IN SOL FRACTION}, volume = 21, year = 1993 }