Vicidomini Caterina, Palumbo Rosanna, Moccia Maria, Roviello Giovanni N
Institute of Biostructures and Bioimaging, Italian National Council for Research (IBB-CNR), Area di Ricerca Site and Headquarters, Via Pietro Castellino 111, 80131 Naples, Italy.
Institute of Crystallography, Italian National Council for Research (IC-CNR), Strada Provinciale 35d, 9, Montelibretti, 00010 Rome, Italy.
J Xenobiot. 2024 Oct 18;14(4):1541-1569. doi: 10.3390/jox14040084.
Plants are continuously exposed to environmental challenges, including pollutants, pesticides, and heavy metals, collectively termed xenobiotics. These substances induce oxidative stress by generating reactive oxygen species (ROS), which can damage cellular components such as lipids, proteins, and nucleic acids. To counteract this, plants have evolved complex metabolic pathways to detoxify and process these harmful compounds. Oxidative stress in plants primarily arises from the overproduction of hydrogen peroxide (HO), superoxide anions (O), singlet oxygen (O), and hydroxyl radicals (OH), by-products of metabolic activities such as photosynthesis and respiration. The presence of xenobiotics leads to a notable increase in ROS, which can result in cellular damage and metabolic disruption. To combat this, plants have developed a strong antioxidant defense mechanism that includes enzymatic antioxidants that work together to eliminate ROS, thereby reducing their harmful effects. In addition to enzymatic defenses, plants also synthesize various non-enzymatic antioxidants, including flavonoids, phenolic acids, and vitamins. These compounds effectively neutralize ROS and help regenerate other antioxidants, offering extensive protection against oxidative stress. The metabolism of xenobiotic substances in plants occurs in three stages: the first involves modification, which refers to the chemical alteration of xenobiotics to make them less harmful. The second involves conjugation, where the modified xenobiotics are combined with other substances to increase their solubility, facilitating their elimination from the plant. The third stage involves compartmentalization, which is the storage or isolation of conjugated xenobiotics in specific parts of the plant, helping to prevent damage to vital cellular functions. Secondary metabolites found in plants, such as alkaloids, terpenoids, and flavonoids, play a vital role in detoxification and the defense against oxidative stress. Gaining a deeper understanding of the oxidative mechanisms and the pathways of xenobiotic metabolism in plants is essential, as this knowledge can lead to the formulation of plant-derived strategies aimed at alleviating the effects of environmental pollution and enhancing human health by improving detoxification and antioxidant capabilities, as discussed in this review.
植物不断面临环境挑战，包括污染物、农药和重金属，这些统称为外源化合物。这些物质通过产生活性氧（ROS）诱导氧化应激，活性氧会损害细胞成分，如脂质、蛋白质和核酸。为了应对这一情况，植物进化出了复杂的代谢途径来解毒和处理这些有害化合物。植物中的氧化应激主要源于过氧化氢（HO）、超氧阴离子（O）、单线态氧（O）和羟基自由基（OH）的过量产生，这些是光合作用和呼吸作用等代谢活动的副产物。外源化合物的存在会导致活性氧显著增加，进而可能导致细胞损伤和代谢紊乱。为了对抗这种情况，植物发展出了强大的抗氧化防御机制，其中包括协同作用以消除活性氧的酶促抗氧化剂，从而降低其有害影响。除了酶促防御外，植物还合成各种非酶促抗氧化剂，包括黄酮类化合物、酚酸和维生素。这些化合物有效地中和活性氧，并有助于再生其他抗氧化剂，提供针对氧化应激的广泛保护。植物中外源化合物的代谢分为三个阶段：第一阶段涉及修饰，即对外源化合物进行化学改变以使其危害降低。第二阶段涉及结合，即修饰后的外源化合物与其他物质结合以增加其溶解度，便于从植物中消除。第三阶段涉及区室化，即将结合后的外源化合物储存或隔离在植物的特定部位，有助于防止对重要细胞功能的损害。植物中发现的次生代谢产物，如生物碱、萜类化合物和黄酮类化合物，在解毒和抗氧化应激防御中起着至关重要的作用。深入了解植物中的氧化机制和外源化合物代谢途径至关重要，因为如本综述所述，这些知识可以促成制定源自植物的策略，旨在通过提高解毒和抗氧化能力来减轻环境污染的影响并增进人类健康。
