Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice  

作　　者：Fanyi Kong Shenggao Lu 

机构地区：[1]Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment,Key Laboratory of Environmental Remediation and Ecosystem Health,Ministry of Education,College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310058,China

出　　处：《Journal of Environmental Sciences》2024年第2期121-132,共12页环境科学学报（英文版）

基　　金：supported by the National Key R&D Program of China (No.2019YFC1803704)。

摘　　要：The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated paddy.With the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased synchronously.The vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction test.Results showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal juice.Based on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy soils.The amino acids(AAs)in brown rice were determined by high-performance liquid chromatography.The contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of SIA.The structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown rice.The formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd.

关 键 词：Cadmium digestibility Soil inorganic amendments Safe rice Amino acid Priming effect Health risk 

分 类 号：X53[环境科学与工程—环境工程]