Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Henan University of Science and Technology, Luoyang, Henan, China.
Department of Civil and Environmental Engineering, Concordia University, Montreal, Canada.
PeerJ. 2024 Sep 24;12:e18001. doi: 10.7717/peerj.18001. eCollection 2024.
Chromium, being among the most toxic heavy metals, continues to demand immediate attention in the remediation of Cr-contaminated environments. In this study, a strain of LBA36 () was isolated from heavy metal contaminated soil in Luanchuan County, Luoyang City, China. The reduction and adsorption rates of LBA36 in 30 mg·L Cr-containing medium were 97.95% and 8.8%, respectively. The reduction mechanism was confirmed by Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy (XPS). Cr(VI) reduction by this strain predominantly occurred outside the cell, with hydroxyl, amide, carboxyl, C-N group, carbonyl, and sulfur carbonyl as the main reaction sites. XPS analysis revealed the presence of Cr and Cr. Furthermore, the hydroponic experiment showed that the fresh weight and plant height of radish seedlings increased by 87.87% and 37.07%, respectively, after inoculation with LBA36 strain under 7 mg·L Cr(VI) stress. The levels of chlorophyll, total protein, malondialdehyde, superoxide dismutase and catalase were also affected to different degrees. In conclusion, this study demonstrated the potential of microbial and phytoremediation in the treatment of heavy metal toxicity, and laid the foundation for the development of effective bioremediation methods for Cr(VI) pollution.
铬是毒性最大的重金属之一，在受铬污染环境的修复中仍需要立即关注。本研究从中国洛阳市栾川县重金属污染土壤中分离到一株 LBA36()。LBA36 在含 30mg·L Cr 的介质中的还原率和吸附率分别为 97.95%和 8.8%。傅里叶变换红外光谱和 X 射线光电子能谱（XPS）证实了还原机制。该菌株主要通过细胞外途径还原 Cr(VI)，其主要反应位点为羟基、酰胺、羧基、C-N 基团、羰基和硫羰基。XPS 分析表明存在 Cr 和 Cr。此外，水培实验表明，在 7mg·L Cr(VI)胁迫下接种 LBA36 菌株后，萝卜幼苗的鲜重和株高分别增加了 87.87%和 37.07%。叶绿素、总蛋白、丙二醛、超氧化物歧化酶和过氧化氢酶的水平也受到不同程度的影响。总之，本研究证明了微生物和植物修复在处理重金属毒性方面的潜力，为开发 Cr(VI)污染的有效生物修复方法奠定了基础。
