Radi Abeer A, Farghaly Fatma A, Al-Kahtany Fatma A, Zaher Ahmed M, Hamada Afaf M
Botany and Microbiology Department, Faculty of Science, Assiut University, Assiut, 71516, Egypt.
Biology Department, Faculty of Science, Ibb University, Ibb, Yemen.
BMC Plant Biol. 2025 Jan 31;25(1):132. doi: 10.1186/s12870-024-05915-7.
Levels of heavy metal pollution are increasing due to industrial activities and urban expansion. While cobalt (Co) can be toxic to plants at high levels and isn't considered essential, it plays a beneficial role in many enzymes and is critical for various biological functions. We conducted experiments to determine how Adhatoda vasica proliferated shoots react to exposure to various Co concentrations (50-1000 µM). We employed physiological and biochemical markers to elucidate the response mechanisms of this medicinal plant. The experiment was conducted in two replicates per treatment. The statistical analysis was based on data from four biological replicates per treatment.
Interestingly, the lowest Co concentration (50 µM) increased proliferated shoot growth by 41.45%. In contrast, higher Co concentrations (100-1000 µM) had detrimental effects on proliferated shoot development, water content, and photosynthetic pigment concentrations. As Co concentration increased, proliferated shoots produced excessive concentrations of reactive oxygen species (ROS). This ROS overproduction is believed to be the primary cause of oxidative damage, as evidenced by the elevated concentrations (18.46%-72.84%) of malondialdehyde (MDA) detected. In response to Co stress, non-enzymatic antioxidants were activated in a concentration-dependent manner. Co administration significantly increased the concentrations of different stress-protective compounds in shoots, including total antioxidants (133.18%), ascorbic acids (217.94%), free and bound phenolics (97.70% and 69.72%, respectively), proline (218.59%), free amino acids (206.96%), soluble proteins (65.97%), and soluble carbohydrates (18.52%). FTIR analysis further corroborated changes in the chemical composition of proliferated shoots. The analysis revealed variations in the peaks associated with major macromolecules, including phenolic compounds, lipids, proteins, carbohydrates, cellulose, hemicellulose, and sugars.
Our study offers the first comprehensive investigation into mechanisms by which Co stress triggers oxidative damage and alters functional groups in the medicinal plant, Adhatoda vasica.
由于工业活动和城市扩张，重金属污染水平不断上升。虽然钴（Co）在高浓度时对植物有毒且不被视为必需元素，但它在许多酶中发挥有益作用，对各种生物学功能至关重要。我们进行了实验，以确定鸭嘴花增殖芽对暴露于不同钴浓度（50 - 1000 µM）的反应。我们采用生理和生化标记来阐明这种药用植物的反应机制。每个处理进行两次重复实验。统计分析基于每个处理四个生物学重复的数据。
有趣的是，最低的钴浓度（50 µM）使增殖芽的生长增加了41.45%。相比之下，较高的钴浓度（100 - 1000 µM）对增殖芽的发育、含水量和光合色素浓度产生了有害影响。随着钴浓度的增加，增殖芽产生了过量的活性氧（ROS）。这种ROS的过度产生被认为是氧化损伤的主要原因，检测到的丙二醛（MDA）浓度升高（18.46% - 72.84%）证明了这一点。为应对钴胁迫，非酶抗氧化剂以浓度依赖的方式被激活。施用钴显著增加了芽中不同应激保护化合物的浓度，包括总抗氧化剂（133.18%）、抗坏血酸（217.94%）、游离和结合酚类（分别为97.70%和69.72%）、脯氨酸（218.59%）、游离氨基酸（206.96%）、可溶性蛋白质（65.97%）和可溶性碳水化合物（18.52%）。傅里叶变换红外光谱（FTIR）分析进一步证实了增殖芽化学成分的变化。分析揭示了与主要大分子相关的峰的变化，包括酚类化合物、脂质、蛋白质、碳水化合物、纤维素、半纤维素和糖类。
我们的研究首次全面调查了钴胁迫触发药用植物鸭嘴花氧化损伤并改变官能团的机制。
