In the present study, citrus low-methoxyl pectin was modified by conjugating cysteine via amide bonds, and the resultant polymer (CYS-PEC) was characterized. CYS-PEC conjugates with thiol contents varying from 77.8 μmol/g to 296 μmol/g were synthesized, and the successful conjugation was evidenced by elemental, and FT-IR analyses. The sulfur in CYS-PEC is predominately in the thiol form, with a minor fraction forming disulfide bonds (∼15%), which occur when thiol/disulfide interchange interrupts the intended thiolation. Both native and modified pectin dispersions exhibited strong pseudoplastic properties, and the frequency sweeps revealed them to be dispersions containing microgel particles. Dynamic viscoelastic analysis was used to determine the oxidation-response gelling capacities of polymer dispersions containing H₂O₂, especially those that are highly thiolated and have cross-linked gel properties. For oxidation-induced CYS-PEC gels, their gelation time, hardness, viscosity and elastic moduli and swelling–disintegration ratio are dependent on the thiol group content, H₂O₂ concentration and polymer concentration.

在本研究中，通过酰胺键结合半胱氨酸对柑橘类低甲氧基果胶进行了修饰，并对所得聚合物（CYS-PEC）进行了表征。CYS-PEC结合物，硫醇含量从77.8μmol  / g到296不等 合成了μmol/ g，并通过元素和FT-IR分析证明了成功的偶联。CYS-PEC中的硫主要以硫醇形式存在，少量形成二硫键（约15％），这是在硫醇/二硫键互换中断预期的硫醇化作用时发生的。天然和改性果胶分散体均显示出强的假塑性，并且频率扫描显示它们是含有微凝胶颗粒的分散体。动态粘弹性分析用于确定含H ₂ O ₂的聚合物分散体的氧化响应胶凝能力，尤其是高度硫醇化并具有交联凝胶特性的那些。对于氧化诱导的CYS-PEC凝胶，其胶凝时间，硬度，粘度和弹性模量以及溶胀-崩解比取决于硫醇基含量，H ₂ O ₂浓度和聚合物浓度。