NOBIPOL, Dept. of Biotechnology, The Norwegian University of Science and Technology, NTNU, NO-7491 Trondheim, Norway.
Carbohydr Polym. 2013 Feb 15;92(2):1026-32. doi: 10.1016/j.carbpol.2012.10.013. Epub 2012 Oct 13.
Water-soluble (1→3)-β-D-glucans with 1,6-linked branches (SBG), originally isolated from the cell walls of Saccharomyces cerevisiae and partially depolymerised to a weight average degree of polymerisation (DP(w)) in the range 120-160 for optimal performance in wound healing applications, were studied by dynamic light scattering (DLS), SEC MALLS and AFM. Results indicate that dilute aqueous SBG solutions (1 μg/ml to 3 mg/ml) contain higher order structures with a very wide size distribution in water (10-500 nm), corresponding to a mixture of single chains, multi-chain aggregates including triple-stranded motifs, and particulate materials. The latter were enriched in longer chains compared to non-particulate fractions. The size distribution of SBG aggregates shifted to slightly lower values upon heating, but showed hysteresis upon cooling. AFM images prepared from very dilute aqueous solution (1-5 μg/ml) analysis showed by comparison to other (1→3)-β-D-glucans that some of the structures were the triple helical species coexisting with larger aggregates and single chains, in contrast to carboxymethylated SBG, which contained predominantly single chains. The ability to control the aggregation behaviour of SBG enables tailoring of the physical, and possibly bioactive, properties of SBG preparations.
水溶性（1→3）-β-D-葡聚糖具有 1,6 连接的支链（SBG），最初从酿酒酵母细胞壁中分离出来，并部分解聚到聚合度（DP(w)）在 120-160 范围内，以在伤口愈合应用中发挥最佳性能，通过动态光散射（DLS）、SEC MALLS 和 AFM 进行了研究。结果表明，稀水溶液 SBG 溶液（1 μg/ml 至 3 mg/ml）在水中含有更高阶结构，具有非常宽的尺寸分布（10-500nm），对应于单链、多链聚集体（包括三股基序）和颗粒物质的混合物。与非颗粒部分相比，后者富含更长的链。在加热时，SBG 聚集体的尺寸分布向略低的值移动，但在冷却时表现出滞后。与其他（1→3）-β-D-葡聚糖相比，通过比较非常稀水溶液（1-5μg/ml）分析制备的 AFM 图像表明，一些结构是与较大聚集体和单链共存的三螺旋物种，而羧甲基化 SBG 则主要包含单链。控制 SBG 聚集行为的能力能够定制 SBG 制剂的物理和可能的生物活性特性。
