Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Sciences, 420111, Lobachevsky Str., 2/31, Kazan, Russian Federation.
Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Sciences, 420111, Lobachevsky Str., 2/31, Kazan, Russian Federation; Kazan (Volga Region) Federal University, Kazan, 420008, Kremlevskaya Str., 18, Kazan, Russian Federation.
Carbohydr Polym. 2017 Sep 1;171:143-151. doi: 10.1016/j.carbpol.2017.05.013. Epub 2017 May 4.
The article presents the structural principles of microwave-induced formation of new gel type from pectic rhamnogalacturonan I (RG-I). The backbone of gel-forming RG-I does not contain consecutive galacturonic residues and modifying groups that can be the cause of junction zone formation as it occurs in course of classical ways of pectin gelation. Microwave irradiation does not cause destruction and chemical modifications of RG-I. Removal of half of galactan chains from RG-I leads to loss of gelling capability pointing out on their leading role in this process. Rising of intensity of the bands attributed to galactose and glycosidic linkages in RG-I gel comparing to solution where this polymer exists as molecule associate indicates that the spatial organization of galactans in gel is changed. A model of the RG-I gelation is proposed: being destabilized at volumetric microwave heating RG-I associates are repacked forming network where RG-I molecules are entangled by galactan chains.
本文介绍了从鼠李半乳糖醛酸聚糖 I（RG-I）中通过微波诱导形成新型凝胶的结构原理。形成凝胶的 RG-I 骨架不含有连续的半乳糖醛酸残基和修饰基团，这可以成为形成连接区的原因，因为这种连接区的形成是在经典果胶凝胶化过程中发生的。微波辐射不会导致 RG-I 的破坏和化学修饰。从 RG-I 中去除一半的半乳糖链会导致失去凝胶能力，这表明它们在这个过程中起主导作用。与该聚合物以分子缔合形式存在的溶液相比，在 RG-I 凝胶中归因于半乳糖和糖苷键的谱带强度的增加表明半乳糖聚糖在凝胶中的空间组织发生了变化。提出了 RG-I 凝胶化的模型：在体积微波加热下，RG-I 缔合体会失稳，重新组装形成网络，其中 RG-I 分子被半乳糖链缠绕。
