铁载体在环境污染与资源利用中的应用研究进展

Review on the Application of Siderophores in Environmental Pollution and Resource Utilization

Fe在地表环境中的生物利用率极低,为了适应低铁环境,微生物和植物会分泌一种低分子量有机化合物--铁载体来螯合环境中的Fe(Ⅲ),以满足自身生命活动需求。铁载体在地表环境中普遍存在,并广泛参与微生物、植物和环境中Fe的迁移和转化。系统总结了铁载体的类型、检测方法以及其在矿物溶解、污染修复、植物促生和生物防治等领域的作用研究进展。结果表明:细菌、真菌、蓝细菌和植物均能产生不同类型铁载体,通过螯合作用从环境中摄取和竞争Fe;依据铁载体中特定的官能团,可采用生物方法和化学方法对其进行定性和定量检测;铁载体可以加速铁硅酸盐矿物和铁氧化物/氢氧化物矿物溶解,推动地表环境中不同相态Fe的生物地球化学循环;铁载体能够螯合多种重金属离子并促进有机污染物降解,修复重金属和有机物污染的土壤,维持土壤良好的生态功能和农业生产能力;铁载体还可以捕获植物所需的营养元素并抑制植物病原菌的繁殖,促进植物生长与产量提高,有效进行生物防治。最后,在综述研究的基础上展望了铁载体的未来研究方向,以期为推动铁载体在环境地学领域的研究发挥积极作用。

Although it is the fourth most abundant element in the Earth s crust,the bioavailability of iron is limited due to the formation of insoluble Fe(Ⅲ)(hydro)oxides under aerobic conditions.Microorganisms like bacteria,fungi and some plants have evolved mechanisms for iron acquisition,one of which is to secrete low molecular weight organic compound called siderophores.Recently,the application of siderophores in iron migration and transformation has aroused tremendous interest due to their ubiquitous presence in the surface environment.The types of siderophores and their detection methods,as well as their applications in the fields of mineral dissolution,pollution remediation,plant growth-promotion and biological control were systematically summarized.The results show that bacteria,fungi,cyanobacteria and plants can produce different types of siderophores,which take up and compete for iron from the environment through chelation.On the basis of the specific functional groups,siderophores can be qualitatively and quantitatively detected by biological and chemical methods.Siderophores can accelerate the dissolution of clay minerals and iron oxide/hydroxide minerals,and promote the biogeochemical cycle of different phases of iron in the surface environment.Siderophores can chelate a variety of heavy metal ions and promote the degradation of organic pollutants,which has great significance in the remediation of soil contaminated by heavy metal and organic matter,maintaining the good ecological function and agricultural production capacity of soil.Siderophores can also capture the nutrients required by plants and inhibit the growth of plant pathogens,play beneficial role in plant protection and growth,and effectively carry out biological control.In addition,prospects for future research trends on siderophores were included,with the aim to promote their developments in the fields of geology and environment.