Endurance assessment of <i>Eichhornia crassipes</i> (Mart.) Solms, in heavy metal contaminated site–A case study

In this study, the ability to hyper accumulate heavy metals from contaminated site by water hyacinth (<i>Eichhornia crassipes</i>) was monitored. The heavy metal-contaminated habitat was validated by X-ray diffraction and energy dispersive X-ray elemental spectrometry analysis of the soil samples. Heavy metal contamination in soil and water; accumulation in foliar, root and bulb tissue samples were determined by atomic absorption spectroscopy and were monitored as a function of accumulation in different tissues. Significant differences were recorded in the bioaccumulation capability of heavy metals by different tissue. Discrete variation in protein profile of leaves and high expression of alcohol dehydrogenase (ADH), peroxidase (POX) and altered regulation of esterase (EST) in root tissue was observed in contaminated site grown <i>Eichhornia</i>. The high metal accumulation efficiency of water hyacinth due to the biomass production suggests this species as reliable organic biomarker for heavy metal contamination.本研究针对凤眼莲（<i>Eichhornia crassipes</i>）从污染场地中超富集重金属的能力进行了监测。通过对土壤样品开展X射线衍射（X-ray diffraction）与能量色散X射线元素光谱法（energy dispersive X-ray elemental spectrometry）分析，验证了该重金属污染生境的污染状况。采用原子吸收光谱法对土壤与水体中的重金属污染水平，以及凤眼莲叶片、根系和球茎组织中的重金属富集量进行了测定，并以不同组织的重金属富集量为变量开展监测分析。结果表明，不同组织对重金属的生物富集能力存在显著差异。在污染场地生长的凤眼莲中，其叶片蛋白质谱呈现离散变异，根系组织内乙醇脱氢酶（alcohol dehydrogenase, ADH）、过氧化物酶（peroxidase, POX）的表达量显著上调，且酯酶（esterase, EST）的调控模式发生改变。鉴于凤眼莲兼具较高的生物量产出与重金属富集效率，该物种可作为重金属污染监测的可靠有机生物标志物（organic biomarker）。