Abstract:

Root border cells (RBCs) of pea were selected as model cells to study the physiological mechanisms and factors influencing silicon alleviation of aluminum (Al) toxicity. Polyvinylimine was used to induce the active biomineralization of aluminum and form nano silicon shells. The physiological mechanisms and effects of different aluminum solutions, such as aluminum chloride, aluminum nitrate, and aluminum sulfate, on the deposition of nano silicon on RBCs walls were studied. The results were as follows: 1) nanosilica can increase the cell viability of RBCs, reduce the entry of reactive aluminum into the cells, lower the level of intracellular reactive oxygen species, and increase the mitochondrial membrane potential (the potentials of aluminum chloride, aluminum nitrate, and aluminum sulfate films increased by 25.68%, 16.80%, and 17.33%, respectively) to reduce the toxic effect of aluminum on RBCs under different environmental conditions. 2) Acid ions in different Al solutions can affect the absorption peak intensity of functional groups in cell wall components, with characteristic peaks at 3380, 2940, 1730, 1650, 1540, 1460, 1170, and 1050 cm⁻¹. However, the absorption peak intensity decreased after nano-Si treatment, indicating that under Al toxicity stress, nano-Si treatment reduced the absorption peak intensity of carboxyl, hydroxyl, and carbonyl groups. 3) Under different aluminum conditions, a nanosilicon layer can be formed on the cell wall of RBCs under PEI induction. Therefore, the mineralized deposition of nano silicon on cells can alleviate the toxic effects of Al ions. The type and concentration of ions can affect the changes in functional groups in the cell wall components of RBCs and the structure of silicon aluminum deposition.

Key words: pea, aluminum toxicity, nanosilica, biosilicification, root border cells

摘要：

为探究硅缓解铝毒的生理机制及影响因子，选择豌豆根边缘细胞为模式细胞，通过聚乙烯亚胺诱导细胞壁上纳米硅与活性铝生物矿化形成纳米硅壳，研究氯化铝、硝酸铝和硫酸铝等不同铝溶液处理对纳米硅在根边缘细胞壁上沉积的生理机制及影响。结果表明，1）不同铝条件下纳米硅能提高根边缘细胞活率，减少活性铝进入细胞，降低细胞内活性氧含量水平以及提高线粒体膜电位，其中氯化铝、硝酸铝和硫酸铝膜电位分别升高了25.7%、16.8%和17.3%，减少了铝毒对根边缘细胞的毒害作用。2）不同铝溶液中的酸根离子能影响细胞壁组分的官能团吸收峰强度，在波长3380、2940、1730、1650、1540、1460、1170、1050 cm⁻¹均有特征峰，但纳米硅处理后吸收峰强度降低，表明在铝毒胁迫下纳米硅处理降低了羧基、羟基、羰基的吸收峰强度。3）不同铝条件下均可以在诱导情况下在根边缘细胞壁上形成纳米硅层，且加硅后细胞壁中均有铝硅酸盐的存在。因此，纳米硅在细胞上的矿化沉积能够缓解铝离子毒害作用，离子种类及浓度等能影响根边缘细胞壁组分中官能团的变化以及硅铝沉积结构。

关键词: 豌豆, 铝毒, 纳米硅, 生物硅化, 根边缘细胞