Innovative Technology, Food and Health Research Group, Facultad de Industrias Alimentarias, Universidad Nacional Agraria La Molina, Av. La Molina s/n, Lima, Peru.
Universidad Nacional José Faustino Sánchez Carrión, Departamento Académico de Ingeniería en Industrias Alimentarias, Huacho, Peru.
Food Chem. 2024 Oct 15;455:139865. doi: 10.1016/j.foodchem.2024.139865. Epub 2024 May 28.
The aim of this research was to graft gallic acid (GA) onto high methoxyl pectin (HMP) through the redox-pair of ascorbic acid (Aa) and hydrogen peroxide (HO) with one- and two-pot procedures. The effectiveness of the both procedures and the chemical, physical and antioxidant properties of the obtained HMP-GA were evaluated. HMP-GA (23.3 ± 0.21 mg GA Equivalent (GAE)/g) and HMP-GA (32.3 ± 0.52 mg GAE/g) were best obtained at HO/Aa molar ratio-HMP/GA weight ratio of 9.0-0.5 and 16.0-0.5, respectively. The UV-Vis and FT-IR spectra and along with their derivative and thermal gravimetric analyses, revealed differences between HMP-GA and HMP-GA. The latter exhibited a greater antioxidant capacity than the former in single electron transfer (ET), hydrogen atom transfer (HAT), and ET-HAT mixed assays. The chemical differences can be attributed to side reactions that may have interfered with the grafting reaction. Consequently, HMP-GA, possessing unique antioxidant and prebiotic properties, can be synthesized through redox-pair procedures.
本研究旨在通过抗坏血酸（Aa）和过氧化氢（HO）的氧化还原对，以一锅法和两锅法将没食子酸（GA）接枝到高甲氧基果胶（HMP）上。评估了两种方法的效果以及所得 HMP-GA 的化学、物理和抗氧化性质。HO/Aa 摩尔比-HMP/GA 重量比分别为 9.0-0.5 和 16.0-0.5 时，可分别得到最佳的 HMP-GA（23.3±0.21mg 没食子酸当量（GAE）/g）和 HMP-GA（32.3±0.52mg GAE/g）。紫外可见和傅里叶变换红外光谱及其导数和热重分析表明 HMP-GA 和 HMP-GA 之间存在差异。后者在单电子转移（ET）、氢原子转移（HAT）和 ET-HAT 混合测定中表现出比前者更大的抗氧化能力。化学差异可归因于可能干扰接枝反应的副反应。因此，具有独特抗氧化和益生元特性的 HMP-GA 可以通过氧化还原对程序合成。
