卡拉胶

卡拉胶是从红藻类的细胞壁中提取的粘多糖。它们是阴离子的线型聚合物，是由具有一个（κ），两个（ι）或三个（λ）硫酸盐的二糖单元的α-1，1,3，4β-半乳聚糖组成。在离子溶液中，κ-和ι-角叉菜胶成螺旋结构的自交联，从而形成刚性或柔性凝胶， λ-角叉菜胶不形成螺旋，属非凝胶。角叉菜胶作为增稠剂和稳定剂是用于商业化。卡拉胶是阴离子型线状的多聚体，每个二糖类单元由带有一个(κ-), 2个(ι-) 或3个(λ-) 硫酸根的1,3α-1,4β-半乳聚糖组成。在离子溶液中，κ- 和 ι-卡拉胶缠绕成螺旋状结构，形成坚固或柔韧的胶体，而λ-卡拉胶不形成螺旋结构，不构成胶体部分，卡拉胶常用作增稠剂和稳定剂。

Carrageenans are mucopolysaccharides from the cell walls of the red algae. They are anionic linear polymers composed of 1,3α-1,4β-galactans having one (κ-), two (ι-) or three (λ-) sulfates per disaccharide unit. In ionic solutions, κ- and ι-carrageenans self-associate into helical structures that form rigid or flexible gels, respectively. λ-carrageenans do not form helices and are non-gelling. Carrageenans are used commercially as thickeners and stabilizing agents.
Carrageenans are used to suppress immune response in vivo and in vitro via mechanisms believed to involve selective cytopathic effect on macrophages. As ι-, κ-, and λ-carrageenans have varying degress of sulfation, they may be studied comparatively for differences in protective, antiviral, and immunosuppression activities.