PDF(Pubmed)
Abstract：
Rice can accumulate more organic and inorganic arsenic (iAs) than other crop plants. In this study, the localization of As in rice grains was investigated using High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) based on 26 rice varieties collected from two provinces. In all the samples, the total As contents in polished rice were 0.03-0.37 mg/kg, with average values of 0.28 and 0.21 mg/kg for two sample sets. The results of the determination of arsenic speciation in different components of rice grain showed that in the polished and brown rice the mean value of arsenite (As(III)) was nearly twice than that of arsenate (As(V)). The regional difference was observed in both total As contents and As speciation. The reason may be that As(III) is more mobile than As(V) in a dissociated form and because of soil properties, rice varieties, and the growing environment. The proportion of iAs and the total As in rice bran was higher than that in polished rice, and this is because As tends accumulate between the husk and the endosperm. In our study, selenium could alleviate the risk of arsenic toxicity at the primary stage of rice growth. Co-exposure to As and Se in germinated rice indicated that the reduction in As accumulation in polished rice reached 73.8%, 76.8%, and 78.3% for total As, As(III), and As(V) when compared with rice treated with As alone. The addition of Se (0.3 mg/kg) along with As significantly reduced the As amount in different parts of germinated rice. Our results indicated that Se biofortification could alleviate the As accumulation and toxicity in rice crops.
摘要：
水稻可以比其他作物植物积累更多的有机和无机砷（iAs）。在这项研究中,基于来自两个省的26个水稻品种，使用高效液相色谱-电感耦合等离子体质谱法（HPLC-ICP-MS）研究了水稻籽粒中As的定位。在所有的样本中,精米中总砷含量为0.03-0.37mg/kg，两组样品的平均值分别为0.28和0.21mg/kg。稻米不同成分中砷形态的测定结果表明，在精米和糙米中，亚砷酸盐（As（III））的平均值几乎是砷酸盐（As（V））的两倍。总砷含量和砷形态均存在区域差异。原因可能是As（III）在解离形式下比As（V）更具流动性，并且由于土壤性质，水稻品种,和成长环境。米糠中iAs和总As的比例高于精米，这是因为As倾向于在外壳和胚乳之间积累。在我们的研究中,硒可以减轻水稻生长初期砷中毒的风险。发芽稻中砷和硒的共同暴露表明，精米中砷的积累减少了73.8％，76.8%,和总As的78.3%，As(III),和As(V)与单独用As处理的水稻相比。硒（0.3mg/kg）和砷的添加显着降低了发芽稻米不同部位的砷含量。我们的结果表明，硒生物强化可以减轻水稻作物中砷的积累和毒性。
