通过TEMPO-催化氧化方法从α-(1 → 3) -glucan制备的多糖酸
Korawit Chitbanyong1, Gaoyuan Hou1, Izumi Shibata1
1Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 113-8657 Tokyo, Japan.
Carbohydrate polymers
|February 17, 2024
概括
在TEMPO催化氧化过程中,不溶于水的α-(1→3) - 葡萄糖被转化为水溶性多糖酸. 这种高效的工艺产生了同质的产品,但也导致了葡萄糖链的显著脱聚合.
科学领域:
- 生物化学和高分子科学 生物化学和高分子科学
- 碳水化合物化学 碳水化合物化学
- 绿色化学 绿色化学
背景情况:
- α-(1→3) - 葡萄糖是一种不溶于水的多糖.
- 多糖的化学修饰可以产生具有新特性的材料.
- 时间催化氧化是一种有效的碳水化合物选择性氧化方法.
研究的目的:
- 在水系统中研究水不溶性α-(1→3) - 葡萄糖的TEMPO-催化氧化.
- 描述产生的氧化产品,重点关注其可溶性,化学结构和氧化程度.
- 评估氧化对葡萄糖分子重量和结构完整性的影响.
主要方法:
- 在pH10的水中使用甲化 (NaOCl) 作为氧化剂,对α-(1→3) - 葡萄糖进行TEMPO-催化氧化.
- 氧化产品的表征使用碳氧含量分析,X射线衍射,固态13CNMR光谱学,以及用多角度激光光散射和折射率检测的尺寸排除色谱.
- 用于分析的碳基组的区域选择性甲基化.
主要成果:
- 获得一种水溶性TEMPO氧化α-(1→3) - 葡萄糖,其质量回收率为97%,C6氧化程度高 (93%).
- 氧化产物,α-(1→3) -多糖酸,呈现出几乎均的化学结构.
- 在氧化过程中发生了显著的脱聚合,高氧化产品的重量平均聚合度从671降至45.
结论:
- TEMPO-催化氧化提供了一条从其不溶性前体中获得水溶性α-(1→3) -多糖酸的定量途径.
- 氧化过程导致葡萄糖结构的结晶性丧失,因为氧化程度增加.
- 实质性脱聚合是这种催化氧化方法的固有结果,无论pH值如何.
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