School of Chemistry, The University of Melbourne, Melbourne, Victoria, 3010, Australia.
Institute of Biology, The University of the Philippines Diliman, 1101, Quezon City, Philippines.
Environ Sci Pollut Res Int. 2020 May;27(15):18498-18509. doi: 10.1007/s11356-020-08285-3. Epub 2020 Mar 20.
The potential of cassava (Manihot esculenta Crantz.) for simultaneous Hg and Au phytoextraction was explored by investigating Hg and Au localization in cassava roots through Micro-Proton Induced X-Ray Emission, High-Resolution Transmission Electron Microscopy (HR-TEM) and X-Ray Diffractometry (XRD). The effect of Hg and Au in the cyanogenic glucoside linamarin distribution was also investigated using Matrix Assisted Laser Desorption Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (MALDI-FT-ICR-MS) imaging. Hg was located mainly in the root vascular bundle of plants grown in 50 or 100 μmol L Hg solutions. Au was localized in the epidermis and cortex or in the epidermis and endodermis for 50 and 100 μmol L Au solutions, respectively. For 50 μmol L solutions of both Hg and Au, the two metals were co-localized in the epidermis. When the Hg concentrations were increased to 100 μmol L, Au was still localized to a considerable extent in the epidermis while Hg was located in all root parts. HR-TEM and XRD revealed that Au nanoparticles were formed in cassava roots. MALDI-FT-ICR-MS imaging showed linamarin distribution in the roots of control and plants and metal-exposed plants thus suggesting that linamarin might be involved in Hg and Au uptake and distribution.
通过微质子诱导 X 射线发射、高分辨率透射电子显微镜（HR-TEM）和 X 射线衍射（XRD）研究了木薯（Manihot esculenta Crantz.）同时吸收汞和金的潜力，研究了汞和金在木薯根中的定位。还使用基质辅助激光解吸电离傅里叶变换离子回旋共振质谱（MALDI-FT-ICR-MS）成像研究了氰苷亚麻苦苷分布中 Hg 和 Au 的影响。Hg 主要位于在 50 或 100 μmol L Hg 溶液中生长的植物的根维管束中。Au 分别定位于 50 和 100 μmol L Au 溶液中的表皮和皮层或表皮和内皮层。对于 50 μmol L 的 Hg 和 Au 溶液，两种金属在表皮中共定位。当 Hg 浓度增加到 100 μmol L 时，Au 仍然在很大程度上定位于表皮，而 Hg 则位于所有根部。HR-TEM 和 XRD 表明在木薯根中形成了 Au 纳米颗粒。MALDI-FT-ICR-MS 成像显示对照和金属暴露植物的根中存在亚麻苦苷分布，这表明亚麻苦苷可能参与了 Hg 和 Au 的吸收和分布。
