Gautam Arti, Pandey Akhilesh Kumar, Dubey Rama Shanker
Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, 221005 India.
Physiol Mol Biol Plants. 2020 Jan;26(1):63-81. doi: 10.1007/s12298-019-00730-z. Epub 2019 Nov 27.
In the present study the potentials of aqueous extracts of the two plants, neem () and Tulsi () were examined in alleviating arsenic toxicity in rice ( L.) plants grown in hydroponics. Seedlings of rice grown for 8 days in nutrient solution containing 50 μM sodium arsenite showed decline in growth, reduced biomass, altered membrane permeability and increased production of superoxide anion O ), HO and hydroxyl radicals (OH). Increased lipid peroxidation marked by elevated TBARS (thiobarbituric acid reactive substances) level, increased protein carbonylation, alterated levels of ascorbate, glutathione and increased activities of enzymes SOD (superoxide dismutase), CAT (catalase), APX (ascorbate peroxidase) and GPX (glutathione peroxidase) were noted in the seedlings on As treatment. Exogenously added leaf aqueous extracts of (0.75 mg mL, w/v) and (0.87 mg mL, w/v) in the growth medium considerably alleviated As toxicity effects in the seedlings, marked by reduced As uptake, restoration of membrane integrity, reduced production of ROS, lowering oxidative damage and restoring the levels of ascorbate, glutathione and activity levels of antioxidative enzymes. Arsenic uptake in the seedlings declined by 72.5% in roots and 72.8% in shoots, when extract was present in the As treatment medium whereas with extract, the uptake declined by 67.2% in roots and 70.01% in shoots. Results suggest that both and aqueous extracts have potentials to alleviate arsenic toxicity in rice plants and that can serve as better As toxicity alleviator compared to .
在本研究中，检测了印楝（Azadirachta indica）和罗勒（Ocimum tenuiflorum）这两种植物水提取物在缓解水培条件下生长的水稻（Oryza sativa L.）植株砷毒性方面的潜力。在含有50 μM亚砷酸钠的营养液中生长8天的水稻幼苗表现出生长下降、生物量减少、膜通透性改变以及超氧阴离子（O₂⁻）、过氧化氢（H₂O₂）和羟基自由基（OH）生成增加。砷处理后的幼苗中，硫代巴比妥酸反应性物质（TBARS）水平升高表明脂质过氧化增加，蛋白质羰基化增加，抗坏血酸、谷胱甘肽水平改变，超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）和谷胱甘肽过氧化物酶（GPX）活性增加。在生长培养基中外源添加印楝（0.75 mg mL⁻¹，w/v）和罗勒（0.87 mg mL⁻¹，w/v）的叶片水提取物，显著缓解了幼苗中的砷毒性效应，表现为砷吸收减少、膜完整性恢复、活性氧生成减少、氧化损伤降低以及抗坏血酸、谷胱甘肽水平和抗氧化酶活性水平恢复。当砷处理培养基中存在印楝提取物时，幼苗根部的砷吸收下降了72.5%，地上部下降了72.8%；而对于罗勒提取物，根部吸收下降了67.2%，地上部下降了70.01%。结果表明，印楝和罗勒的水提取物都有缓解水稻植株砷毒性的潜力，并且与罗勒相比，印楝可作为更好的砷毒性缓解剂。
